Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1051/0004-6361/202450702e

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

Galaxy clusters, being the most massive objects in the Universe, exhibit the strongest alignment with the large-scale structure. However, mis-identification of members due to projection effects from the large-scale structure can occur. We studied the impact of projection effects on the measurement of the intrinsic alignment of galaxy clusters, using galaxy cluster mock catalogues. Our findings showed that projection effects result in a decrease of the large-scale intrinsic alignment signal of the cluster and produce a bump at rp ∼ 1 h-1 Mpc, most likely due to interlopers and missed member galaxies. This decrease in signal explains the observed similar alignment strength between bright central galaxies and clusters in the SDSS redMaPPer cluster catalogue. The projection effect and cluster intrinsic alignment signal are coupled, with clusters having lower fractions of missing members or having higher fraction of interlopers exhibiting higher alignment signals in their projected shapes. We aim to use these findings to determine the impact of projection effects on galaxy cluster cosmology in future studies.

DOI： 10.1093/mnras/stae064

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We measure weak lensing cosmic shear power spectra from the 3-year galaxy shear catalog of the Hyper Suprime-Cam (HSC) Subaru Strategic Program imaging survey. The shear catalog covers 416 deg2 of the northern sky, with a mean i-band seeing of 0.59 arcsec and an effective galaxy number density of 15 arcmin-2 within our adopted redshift range. With an i-band magnitude limit of 24.5 mag, and four tomographic redshift bins spanning 0.3≤zph≤1.5 based on photometric redshifts, we obtain a high-significance measurement of the cosmic shear power spectra, with a signal-to-noise ratio of approximately 26.4 in the multipole range 300<ℓ<1800. The accuracy of our power spectrum measurement is tested against realistic mock shear catalogs, and we use these catalogs to get a reliable measurement of the covariance of the power spectrum measurements. We use a robust blinding procedure to avoid confirmation bias, and model various uncertainties and sources of bias in our analysis, including point spread function systematics, redshift distribution uncertainties, the intrinsic alignment of galaxies and the modeling of the matter power spectrum. For a flat ΛCDM model, we find S8σ8(ωm/0.3)0.5=0.776-0.033+0.032, which is in excellent agreement with the constraints from the other HSC Year 3 cosmology analyses, as well as those from a number of other cosmic shear experiments. This result implies a ∼2σ-level tension with the Planck 2018 cosmology. We study the effect that various systematic errors and modeling choices could have on this value, and find that they can shift the best-fit value of S8 by no more than ∼0.5σ, indicating that our result is robust to such systematics.

DOI： 10.1103/PhysRevD.108.123519

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We utilize the Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey (SDSS-BOSS) galaxies and its overlap with approximately 416 sq degrees of deep grizy-band imaging from the Subaru Hyper Suprime-Cam Survey (HSC). We perform measurements of three two-point correlations which form the basis of the cosmological inference presented in our companion papers, Miyatake et al. and Sugiyama et al. We use three approximately volume limited subsamples of spectroscopic galaxies by their i-band magnitude from the SDSS-BOSS: LOWZ (0.1<z<0.35), CMASS1 (0.43<z<0.55) and CMASS2 (0.55<z<0.7), respectively. We present high signal-to-noise ratio measurements of the projected correlation functions of these galaxies, which is expected to be proportional to the projected matter correlation function on large scales with a proportionality constant dependent on the bias of galaxies. In order to help break the degeneracy between the amplitude of the matter correlation and the bias of these spectroscopic galaxies, we use the distortions of the shapes of fainter galaxies in HSC due to weak gravitational lensing, to measure the galaxy-galaxy lensing signal, which probes the projected galaxy-matter cross-correlation function of the SDSS-BOSS galaxies. We also measure the cosmic shear correlation functions from HSC galaxies which is related to the projected matter correlation function. We demonstrate the robustness of our measurements by subjecting each of them to a variety of systematic tests. Our use of a single sample of HSC source galaxies is crucial to calibrate any residual systematic biases in the inferred redshifts of our galaxies. We also describe the construction of a suite of mocks: (i) spectroscopic galaxy catalogs which obey the clustering and abundance of each of the three SDSS-BOSS subsamples, and (ii) galaxy shape catalogs which obey the footprint of the HSC survey and have been appropriately sheared by the large-scale structure expected in a Λ Cold Dark Matter model. We use these mock catalogs to compute the covariance of each of our observables.

DOI： 10.1103/PhysRevD.108.123520

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We present cosmological parameter constraints from a blind joint analysis of three two-point correlation functions measured from the Year 3 Hyper Suprime-Cam (HSC-Y3) imaging data, covering about 416 deg2, and the SDSS DR11 spectroscopic galaxies spanning the redshift range [0.15, 0.70]. We subdivide the SDSS galaxies into three luminosity-cut, and therefore nearly volume-limited samples separated in redshift, each of which acts as a large-scale structure tracer characterized by the measurement of the projected correlation function, wp(R). We also use the measurements of the galaxy-galaxy weak-lensing signal Δς(R) for each of these SDSS samples which act as lenses for a secure sample of source galaxies selected from the HSC-Y3 shape catalog based on their photometric redshifts. We combine these measurements with the cosmic shear correlation functions, ζ± measured for our HSC source sample. We model these observables with the minimal bias model of the galaxy clustering observables in the context of a flat ΛCDM cosmology. We use conservative scale cuts, R>12 and 8h-1 Mpc for Δς and wp, respectively, where the minimal bias model is valid, in addition to conservative prior on the residual bias in the mean redshift of the HSC photometric source galaxies. We present various validation tests of our model as well as analysis methods. Our baseline analysis yields S8=0.775-0.038+0.043 (68% C.I.) for the ΛCDM model, after marginalizing over uncertainties in other parameters. Our value of S8 is consistent with that from the Planck 2018 data, but the credible interval of our result is still relatively large. We show that various internal consistency tests based on different splits of the data are passed. Our results are statistically consistent with those of a companion paper, which extends this analysis to smaller scales with an emulator-based halo model, using Δς(R) and wp(R) down to R>3 and 2h-1 Mpc, respectively.

DOI： 10.1103/PhysRevD.108.123521

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We perform a blinded cosmology analysis with cosmic shear two-point correlation functions measured from more than 25 million galaxies in the Hyper Suprime-Cam three-year shear catalog in four tomographic redshift bins ranging from 0.3 to 1.5. After conservative masking and galaxy selection, the survey covers 416 deg2 of the northern sky with an effective galaxy number density of 15 arcmin-2 over the four redshift bins. The 2PCFs adopted for cosmology analysis are measured in the angular range; 7.1<θ/arcmin<56.6 for ζ+ and 31.2<θ/arcmin<248 for ζ-, with a total signal-to-noise ratio of 26.6. We apply a conservative, wide, flat prior on the photometric redshift errors on the last two tomographic bins, and the relative magnitudes of the cosmic shear amplitude across four redshift bins allow us to calibrate the photometric redshift errors. With this flat prior on redshift errors, we find ωm=0.256-0.044+0.056 and S8σ8ωm/0.3=0.769-0.034+0.031 (both 68% C.I.) for a flat Λ cold dark matter cosmology. We find, after unblinding, that our constraint on S8 is consistent with the Fourier space cosmic shear and the 3×2 pt analyses on the same HSC dataset. We carefully study the potential systematics from astrophysical and systematic model uncertainties in our fiducial analysis using synthetic data, and report no biases (including projection bias in the posterior space) greater than 0.5σ in the estimation of S8. Our analysis hints that the mean redshifts of the two highest tomographic bins are higher than initially estimated. In addition, a number of consistency tests are conducted to assess the robustness of our analysis. Comparing our result with Planck-2018 cosmic microwave background observations, we find a ∼2σ tension for the ΛCDM model.

DOI： 10.1103/PhysRevD.108.123518

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

We investigate the robustness of baryon acoustic oscillations (BAO) measurements with a photometric galaxy sample using mock galaxy catalogues with various sizes of photometric redshift (photo-z) uncertainties. We first conduct the robustness of BAO measurements, assuming we have a perfect knowledge of photo-z uncertainties. We find that the BAO shift parameter α can be constrained in an unbiased manner even for 3 per cent photometric redshift uncertainties up to z ∼ 1. For instance, α = 1.006 ± 0.078 with 95 per cent confidence level is obtained from 3 per cent photo-z uncertainty data at z = 1.03 using the sample of M∗ ≥ 1010.25 M☉ h−2. We also find that a sparse galaxy sample, e.g. <2 × 10−4 [h Mpc−1]3, causes additional noise in the covariance matrix calculation and can bias the constraint on α. Following this, we look into the scenario where incorrect photometric redshift uncertainties are assumed in the fitting model. We find that underestimating the photo-z uncertainty leads to a degradation in the constraining power on α. However, the constrained value of α is not biased. We also quantify the constraining power on Ωm0 assuming the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST)-like covariance and find that the 95 per cent confidence level is σ(Ωm0) ∼ 0.03–0.05 corresponding to the photo-z uncertainties of 1–3 per cent, respectively. Finally, we examine whether the skewness in the photometric redshift can bias the constraint on α and confirm that the constraint on α is unbiased, even assuming a Gaussian photo-z uncertainty in our model.

DOI： 10.1093/mnras/stad3078

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

Cosmological weak lensing measurements rely on a precise measurement of the shear two-point correlation function (2PCF) along with a deep understanding of systematics that affect it. In this work, we demonstrate a general framework for detecting and modelling the impact of PSF systematics on the cosmic shear 2PCF and mitigating its impact on cosmological analysis. Our framework can detect PSF leakage and modelling error from all spin-2 quantities contributed by the PSF second and higher moments, rather than just the second moments, using the cross-correlations between galaxy shapes and PSF moments. We interpret null tests using the HSC Year 3 (Y3) catalogs with this formalism and find that leakage from the spin-2 combination of PSF fourth moments is the leading contributor to additive shear systematics, with total contamination that is an order-of-magnitude higher than that contributed by PSF second moments alone. We conducted a mock cosmic shear analysis for HSC Y3 and find that, if uncorrected, PSF systematics can bias the cosmological parameters m and S8 by ∼0.3σ. The traditional second moment-based model can only correct for a 0.1σ bias, leaving the contamination largely uncorrected. We conclude it is necessary to model both PSF second and fourth moment contaminations for HSC Y3 cosmic shear analysis. We also reanalyse the HSC Y1 cosmic shear analysis with our updated systematics model and identify a 0.07σ bias on m when using the more restricted second moment model from the original analysis. We demonstrate how to self-consistently use the method in both real space and Fourier space, assess shear systematics in tomographic bins, and test for PSF model overfitting.

DOI： 10.1093/mnras/stad1801

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

We present posterior sample redshift distributions for the Hyper Suprime-Cam Subaru Strategic Program Weak Lensing three-year (HSC Y3) analysis. Using the galaxies' photometry and spatial cross-correlations, we conduct a combined Bayesian Hierarchical Inference of the sample redshift distributions. The spatial cross-correlations are derived using a subsample of Luminous Red Galaxies (LRGs) with accurate redshift information available up to a photometric redshift of z < 1.2. We derive the photometry-based constraints using a combination of two empirical techniques calibrated on spectroscopic and multiband photometric data that cover a spatial subset of the shear catalogue. The limited spatial coverage induces a cosmic variance error budget that we include in the inference. Our cross-correlation analysis models the photometric redshift error of the LRGs to correct for systematic biases and statistical uncertainties. We demonstrate consistency between the sample redshift distributions derived using the spatial cross-correlations, the photometry, and the posterior of the combined analysis. Based on this assessment, we recommend conservative priors for sample redshift distributions of tomographic bins used in the three-year cosmological Weak Lensing analyses.

DOI： 10.1093/mnras/stad1962

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We present constraints on the flat $\Lambda$CDM cosmological model through a
joint analysis of galaxy abundance, galaxy clustering and galaxy-galaxy lensing
observables with the Kilo-Degree Survey. Our theoretical model combines a
flexible conditional stellar mass function, to describe the galaxy-halo
connection, with a cosmological N-body simulation-calibrated halo model to
describe the non-linear matter field. Our magnitude-limited bright galaxy
sample combines 9-band optical-to-near-infrared photometry with an extensive
and complete spectroscopic training sample to provide accurate redshift and
stellar mass estimates. Our faint galaxy sample provides a background of
accurately calibrated lensing measurements. We constrain the structure growth
parameter $S_8=\sigma_8\sqrt{\Omega_{\mathrm{m } }/0.3}=0.773^{+0.028}_{-0.030}$,
and the matter density parameter $\Omega_{\mathrm{m } }=0.290^{+0.021}_{-0.017}$.
The galaxy-halo connection model adopted in the work is shown to be in
agreement with previous studies. Our constraints on cosmological parameters are
comparable to, and consistent with, joint $3\times2{\mathrm{pt } }$
clustering-lensing analyses that additionally include a cosmic shear
observable. This analysis therefore brings attention to the significant
constraining power in the often-excluded non-linear scales for galaxy
clustering and galaxy-galaxy lensing observables. By adopting a theoretical
model that accounts for non-linear halo bias, halo exclusion, scale-dependent
galaxy bias and the impact of baryon feedback, this work demonstrates the
potential and a way forward to include non-linear scales in cosmological
analyses. Varying the width of the satellite galaxy distribution with an
additional parameter yields a strong preference for sub-Poissonian variance,
improving the goodness of fit by 0.18 in reduced $\chi^{2}$ value compared to a
fixed Poisson distribution.

DOI： 10.1051/0004-6361/202245158

Web of Science

Scopus

arXiv

Other Link： http://arxiv.org/pdf/2210.03110v2

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

Abstract

Since the discovery of the accelerated expansion of the present Universe, significant theoretical developments have been made in the area of modified gravity. In the meantime, cosmological observations have been providing more high-quality data, allowing us to explore gravity on cosmological scales. To bridge the recent theoretical developments and observations, we present an overview of a variety of modified theories of gravity and the cosmological observables in the cosmic microwave background and large-scale structure, supplemented with a summary of predictions for cosmological observables derived from cosmological perturbations and sophisticated numerical studies. We specifically consider scalar-tensor theories in the Horndeski and DHOST family, massive gravity/bigravity, vector-tensor theories, metric-affine gravity, and cuscuton/minimally-modified gravity, and discuss the current status of those theories with emphasis on their physical motivations, validity, appealing features, the level of maturity, and calculability. We conclude that the Horndeski theory is one of the most well-developed theories of modified gravity, although several remaining issues are left for future observations. The paper aims to help to develop strategies for testing gravity with ongoing and forthcoming cosmological observations.

DOI： 10.1093/ptep/ptad052

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

In this series of papers, we present a simulation-based model for the non-linear clustering of galaxies based on separate modelling of clustering in real space and velocity statistics. In the first paper, we present an emulator for the real-space correlation function of galaxies, whereas the emulator of the real-to-redshift space mapping based on velocity statistics is presented in the second paper. Here, we show that a neural network emulator for real-space galaxy clustering trained on data extracted from the dark quest suite of N-body simulations achieves sub-per cent accuracies on scales 1 < r < 30 h-1 Mpc, and better than 3 per cent on scales r < 1 h-1 Mpc in predicting the clustering of dark-matter haloes with number density 10-3.5 (h-1 Mpc)-3, close to that of SDSS LOWZ-like galaxies. The halo emulator can be combined with a galaxy-halo connection model to predict the galaxy correlation function through the halo model. We demonstrate that we accurately recover the cosmological and galaxy-halo connection parameters when galaxy clustering depends only on the mass of the galaxies' host halos. Furthermore, the constraining power in σ8 increases by about a factor of 2 when including scales smaller than 5h-1 Mpc. However, when mass is not the only property responsible for galaxy clustering, as observed in hydrodynamical or semi-analytic models of galaxy formation, our emulator gives biased constraints on σ8. This bias disappears when small scales (r < 10 h-1 Mpc) are excluded from the analysis. This shows that a vanilla halo model could introduce biases into the analysis of future data sets.

DOI： 10.1093/mnras/stad1207

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

We present the splashback radius measurements around the SRG/eROSITA eFEDS X-ray selected galaxy clusters by cross-correlating them with HSC S19A photometric galaxies. The X-ray selection is expected to be less affected by systematics related to projection that affects optical cluster finder algorithms. We use a nearly volume-limited sample of 109 galaxy clusters selected in 0.5-2.0 keV band having luminosity LX > 1043.5 erg s−1 h−2 within the redshift z < 0.75 and obtain measurements of the projected cross-correlation with a signal to noise of 17.43. We model our measurements to infer a 3D profile and find that the steepest slope is sharper than −3 and associate the location with the splashback radius. We infer the value of the 3D splashback radius rsp = 1.45+−002630 h−1 Mpc. We also measure the weak-lensing signal of the galaxy clusters and obtain halo mass log[M200m/h−1 M☉] = 14.52 ± 0.06 using the HSC-S16A shape catalogue data at the median redshift z = 0.46 of our cluster sample. We compare our rsp values with the spherical overdensity boundary r200m = 1.75 ± 0.08 h−1 Mpc based on the halo mass, which is consistent within 1.2σ with the ЛCDM predictions. Our constraints on the splashback radius, although broad, are the best measurements thus far obtained for an X-ray selected galaxy cluster sample.

DOI： 10.1093/mnras/stad1239

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We present high angular resolution measurements of the thermal Sunyaev–Zel’dovich effect (SZE) toward two galaxy clusters, RCS J2319+0038 at z = 0.9 and HSC J0947−0119 at z = 1.1, by the Atacama Large Millimeter/submillimeter Array (ALMA) in Band 3. They are supplemented with available Chandra X-ray data, optical data taken by Hyper Suprime-Cam on Subaru, and millimeter-wave SZE data from the Atacama Cosmology Telescope. Taking into account departures from spherical symmetry, we have reconstructed non-parametrically the inner pressure profile of two clusters as well as electron temperature and density profiles for RCS J2319+0038. This is one of the first such measurements for an individual cluster at z ≳ 0.9. We find that the inner pressure profile of both clusters is much shallower than that of local cool-core clusters. Our results consistently suggest that RCS J2319+0038 hosts a weak cool core, where radiative cooling is less significant than in local cool cores. On the other hand, HSC J0947−0119 exhibits an even shallower pressure profile than RCS J2319+0038 and is more likely to be a non-cool-core cluster. The SZE centroid position is offset by more than 140 h−170 kpc from the peaks of galaxy distribution in HSC J0947−0119, suggesting a stronger influence of mergers in this cluster. We conclude that these distant clusters are at a very early stage of developing the cool cores typically found in clusters at lower redshifts.

DOI： 10.1093/pasj/psac110

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

Cosmological parameter constraints from recent galaxy imaging surveys are reaching percent-level accuracy on the effective amplitude of the lensing signal, S8. The upcoming Legacy Survey of Space and Time (LSST) of the Vera C. Rubin Observatory will produce subpercent level measurements of cosmological parameters, providing a milestone test of the CDM model. To supply guidance to the upcoming LSST analysis, it is important to understand thoroughly the results from different recent galaxy imaging surveys and assess their consistencies. In this work, we perform a unified catalogue-level reanalysis of three cosmic shear data sets: the first year data from the Dark Energy Survey (DES-Y1), the 1000 deg2 data set from the Kilo-Degree Survey (KiDS-1000), and the first year data from the Hyper Suprime-Cam Subaru Strategic Program (HSC-Y1). We utilize a pipeline developed and rigorously tested by the LSST Dark Energy Science Collaboration to perform the reanalysis and assess the robustness of the results to analysis choices. We find the S8 constraint to be robust to two different small-scale modelling approaches, and varying choices of cosmological priors. Our unified analysis allows the consistency of the surveys to be rigorously tested, and we find the three surveys to be statistically consistent. Due to the partially overlapping footprint, we model the cross-covariance between KiDS-1000 and HSC-Y1 approximately when combining all three data sets, resulting in a 1.6–1.9 per cent constraint on S8 given different assumptions on the cross-covariance.

DOI： 10.1093/mnras/stad246

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

We present a novel analysis for cluster cosmology that fully forward models the abundances, weak lensing, and the clustering of galaxy clusters. Our analysis notably includes an empirical model for the anisotropic boosts impacting the lensing and clustering signals of optical clusters. These boosts arise from a preferential selection of clusters surrounded by anisotropic large-scale structure, a consequence of the limited discrimination between line-of-sight interlopers and true cluster members offered by photometric surveys. We validate our analysis via a blind cosmology challenge on mocks, and find that we can obtain tight and unbiased cosmological constraints without informative priors or external calibrations on any of our model parameters. We then apply our analysis on the SDSS redMaPPer clusters, and find results favoring low cm and high σ8, combining to yield the lensing strength constraint S8 = 0.715-0.021+0.024. We investigate potential drivers behind these results through a series of post-unblinding tests, noting that our results are consistent with existing cluster cosmology constraints but clearly inconsistent with other CMB/LSS based cosmology results. From these tests, we find hints that a suppression in the cluster lensing signal may be driving our results.

DOI： 10.1093/mnras/stac3410

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：EDP Sciences  

Context. We present the results of a systematic X-ray analysis of optically rich galaxy clusters detected by the Subaru Hyper Suprime-Cam (HSC) survey in the eROSITA Final Equatorial-Depth Survey (eFEDS) field.

Aims. Through a joint analysis of the SRG (Spectrum Roentgen Gamma)/eROSITA and Subaru/HSC surveys, we aim to investigate the dynamical status of the optically selected clusters and to derive the cluster scaling relations.

Methods. The sample consists of 43 optically selected galaxy clusters with a richness &gt;40 in the redshift range of 0.16–0.89. We systematically analyzed the X-ray images and emission spectra using the eROSITA data. We identified the brightest cluster galaxy (BCG) using the optical and far-infrared databases. We evaluated the cluster’s dynamical status by measuring three quantities: offset between the X-ray peak and BCG position, the gas concentration parameter, and the number of galaxy-density peaks. We investigated the luminosity–temperature and mass–luminosity relations based on eROSITA X-ray spectra and HSC weak-lensing data analyses.

Results. Based on these three measurements, we estimated the fraction of relaxed clusters to be 2(&lt; 39)%, which is smaller than that of the X-ray-selected cluster samples. After correcting for a selection bias due to the richness cut, we obtained a shallow L−T slope of 2.1 ± 0.5, which is consistent with the predictions of the self-similar model and the baseline model incorporating a mass–concentration relation. The L−M slope of 1.5 ± 0.3 is in agreement with the above-cited theoretical models as well as the data on the shear-selected clusters in the eFEDs field.

Conclusions. Our analysis of high-richness optical clusters yields a small fraction of relaxed clusters and a shallow slope for the luminosity–temperature relation. This suggests that the average X-ray properties of the optical clusters are likely to be different from those observed in the X-ray samples. Thus, the joint eROSITA and HSC observations are a powerful tool in extending the analysis to a larger sample and understanding the selection effect with a view to establish cluster scaling relations.

DOI： 10.1051/0004-6361/202244260

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Monthly Notices of the Royal Astronomical Society  

We evaluate the consistency between lensing and clustering based on measurements from Baryon Oscillation Spectroscopic Survey combined with galaxy-galaxy lensing from Dark Energy Survey (DES) Year 3, Hyper Suprime-Cam Subaru Strategic Program (HSC) Year 1, and Kilo-Degree Survey (KiDS)-1000. We find good agreement between these lensing data sets. We model the observations using the Dark Emulator and fit the data at two fixed cosmologies: Planck (S8 = 0.83), and a Lensing cosmology (S8 = 0.76). For a joint analysis limited to large scales, we find that both cosmologies provide an acceptable fit to the data. Full utilization of the higher signal-to-noise small-scale measurements is hindered by uncertainty in the impact of baryon feedback and assembly bias, which we account for with a reasoned theoretical error budget. We incorporate a systematic inconsistency parameter for each redshift bin, A, that decouples the lensing and clustering. With a wide range of scales, we find different results for the consistency between the two cosmologies. Limiting the analysis to the bins for which the impact of the lens sample selection is expected to be minimal, for the Lensing cosmology, the measurements are consistent with A = 1; A = 0.91 ± 0.04 (A = 0.97 ± 0.06) using DES+KiDS (HSC). For the Planck case, we find a discrepancy: A = 0.79 ± 0.03 (A = 0.84 ± 0.05) using DES+KiDS (HSC). We demonstrate that a kinematic Sunyaev-Zeldovich-based estimate for baryonic effects alleviates some of the discrepancy in the Planck cosmology. This analysis demonstrates the statistical power of small-scale measurements; however, caution is still warranted given modelling uncertainties and foreground sample selection effects.

DOI： 10.1093/mnras/stac2938

Web of Science

Scopus

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

DOI： 10.1103/PhysRevD.106.083519

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Astronomy and Astrophysics  

The halo assembly bias, a phenomenon referring to dependencies of the large-scale bias of a dark matter halo other than its mass, is a fundamental property of the standard cosmological model. First discovered in 2005 from the Millennium Run simulation, it has been proven very diffcult to be detected observationally, with only a few convincing claims of detection so far. The main obstacle lies in finding an accurate proxy of the halo formation time. In this study, by utilizing a constrained simulation that can faithfully reproduce the observed structures larger than 2 Mpc in the local universe, for a sample of 634 massive clusters at z ≤ 0.12, we found their counterpart halos in the simulation and used the mass growth history of the matched halos to estimate the formation time of the observed clusters. This allowed us to construct a pair of early- and late-forming clusters, with a similar mass as measured via weak gravitational lensing, and large-scale biases differing at the ≈3σ level, suggestive of the signature of assembly bias, which is further corroborated by the properties of cluster galaxies, including the brightest cluster galaxy and the spatial distribution and number of member galaxies. Our study paves a way to further detect assembly bias based on cluster samples constructed purely on observed quantities.

DOI： 10.1051/0004-6361/202244404

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of Cosmology and Astroparticle Physics  

Galaxy clusters are a promising probe of late-time structure growth, but constraints on cosmology from cluster abundances are currently limited by systematics in their inferred masses. One unmitigated systematic effect in weak-lensing mass inference is ignoring the presence of baryons and treating the entire cluster as a dark matter halo. In this work we present a new flexible model for cluster densities that captures both the baryonic and dark matter profiles, a new general technique for calculating the lensing signal of an arbitrary density profile, and a methodology for stacking those lensing signal to appropriately model stacked weak-lensing measurements of galaxy cluster catalogues. We test this model on 1400 simulated clusters. Similarly to previous studies, we find that a dark matter-only model overestimates the average mass by 7.5%, but including our baryonic term reduces that to 0.7%. Since two more variables are marginalized over when we include our baryonic term the posteriors on the cluster mass calibration are larger than the dark matter-only model. Additionally, to mitigate the computational complexity of our model, we construct an emulator (surrogate model) which accurately interpolates our model for parameter inference, while being much faster to use than the raw model. We also provide an open-source software framework for our model and emulator, called maszcal, which will serve as a platform for continued efforts to improve these mass-calibration techniques. In this work, we detail our model, the construction of the emulator, and the tests which we used to validate that our model does mitigate bias. Lastly, we describe tests of the emulator's accuracy.

DOI： 10.1088/1475-7516/2022/10/034

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We determine the error introduced in a joint halo model analysis of galaxy-galaxy lensing and galaxy clustering observables when adopting the standard approximation of linear halo bias. Considering the Kilo-Degree Survey, we forecast that ignoring the non-linear halo bias would result in up to 5σ offsets in the recovered cosmological parameters describing structure growth, S8, and the matter density parameter, m. We include the scales 10-1.3< rp/h-1Mpc< 10 in the data vector, and the direction of these offsets are shown to depend on the freedom afforded to the halo model through other nuisance parameters. We conclude that a beyond-linear halo bias correction must therefore be included in future cosmological halo model analyses of large-scale structure observables on non-linear scales.

DOI： 10.1093/mnras/stac1858

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing Ltd  

We present the Local Volume Complete Cluster Survey (LoVoCCS; we pronounce it as "low-vox" or "law-vox," with stress on the second syllable), an NSF's National Optical-Infrared Astronomy Research Laboratory survey program that uses the Dark Energy Camera to map the dark matter distribution and galaxy population in 107 nearby (0.03 < z < 0.12) X-ray luminous ([0.1-2.4 keV] L (X500) > 10(44) erg s(-1)) galaxy clusters that are not obscured by the Milky Way. The survey will reach Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) Year 1-2 depth (for galaxies r = 24.5, i = 24.0, signal-to-noise ratio (S/N) > 20; u = 24.7, g = 25.3, z = 23.8, S/N > 10) and conclude in similar to 2023 (coincident with the beginning of LSST science operations), and will serve as a zeroth-year template for LSST transient studies. We process the data using the LSST Science Pipelines that include state-of-the-art algorithms and analyze the results using our own pipelines, and therefore the catalogs and analysis tools will be compatible with the LSST. We demonstrate the use and performance of our pipeline using three X-ray luminous and observation-time complete LoVoCCS clusters: A3911, A3921, and A85. A3911 and A3921 have not been well studied previously by weak lensing, and we obtain similar lensing analysis results for A85 to previous studies. (We mainly use A3911 to show our pipeline and give more examples in the Appendix.)

DOI： 10.3847/1538-4357/ac68e8

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

We present cosmological parameter constraints from a blinded joint analysis of galaxy-galaxy weak lensing, Δς(R), and the projected correlation function, wp(R), measured from the first-year HSC (HSC-Y1) data and SDSS spectroscopic galaxies over 0.15<z<0.7. We use luminosity-limited samples as lens samples for Δς and as large-scale structure tracers for wp in three redshift bins, and use the HSC-Y1 galaxy catalog to define a secure sample of source galaxies at zph>0.75 for the Δς measurements, selected based on their photometric redshifts. As a theoretical template, we use the "minimal bias"model for the cosmological clustering observables for the flat ΛCDM cosmological model. We compare the model predictions with the measurements in each redshift bin on large scales, R>12 and 8h-1 Mpc for Δς(R) and wp(R), respectively, where the perturbation-theory-inspired model is valid. As part of our model, we account for the effect of lensing magnification bias on the Δς measurements. When we employ weak priors on cosmological parameters, without cosmic microwave background (CMB) information, we find S8=0.936-0.086+0.092, σ8=0.85-0.11+0.16, and ωm=0.283-0.035+0.12 (mode and 68% credible interval) for the flat ΛCDM model. Although the central value of S8 appears to be larger than those inferred from other cosmological experiments, we find that the difference is consistent with expected differences due to sample variance, and our results are consistent with the other results to within the statistical uncertainties. When combined with the Planck 2018 likelihood for the primary CMB anisotropy information (TT,TE,EE+lowE), we find S8=0.817-0.021+0.022, σ8=0.892-0.056+0.051, ωm=0.246-0.035+0.045, and the equation-of-state parameter of dark energy, wde=-1.28-0.19+0.20 for the flat wCDM model, which is consistent with the flat ΛCDM model to within the error bars.

DOI： 10.1103/PhysRevD.105.123537

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：EDP SCIENCES S A  

We present the first weak-lensing mass calibration and X-ray scaling relations of galaxy clusters and groups selected in the eROSITA Final Equatorial Depth Survey (eFEDS) observed by Spectrum Roentgen Gamma/eROSITA over a contiguous footprint with an area of approximate to 140 deg(2), using the three-year (S19A) weak-lensing data from the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey. In this work, we study a sample of 434 optically confirmed galaxy clusters (and groups) at redshift 0.01 less than or similar to z less than or similar to 1.3 with a median of 0.35, of which 313 systems are uniformly covered by the HSC survey to enable the extraction of the weak-lensing shear observable. In a Bayesian population modeling, we perform a blind analysis for the weak-lensing mass calibration by simultaneously modeling the observed count rate eta and the shear profile g(+) of individual clusters through the count-rate-to-mass-and-redshift (eta-M-500-z) relation and the weak-lensing-mass-to-mass-and-redshift (M-WL-M-500-z) relation, respectively, while accounting for the bias in these observables using simulation-based calibrations. As a result, the count-rate-inferred and lensing-calibrated cluster mass is obtained from the joint modeling of the scaling relations, as the ensemble mass spanning a range of 10(13)h(-1)M(circle dot) less than or similar to M-500 less than or similar to 10(15)h(-1)M(circle dot) with a median of approximate to 10(14)h(-1)M(circle dot) for the eFEDS sample. With the mass calibration, we further model the X-ray observable-to-mass-and-redshift relations, including the rest-frame soft-band and bolometric luminosity (L-X and L-b), the emission-weighted temperature T-X, the mass of intra-cluster medium M-g, and the mass proxy Y-X, which is the product of T-X and M-g. Except for L-X with a steeper dependence on the cluster mass at a statistically significant level, we find that the other X-ray scaling relations all show a mass trend that is statistically consistent with the self-similar prediction at a level of less than or similar to 1.7 sigma. Meanwhile, all these scaling relations show no significant deviation from the self-similarity in their redshift scaling. Moreover, no significant redshift-dependent mass trend is present. This work demonstrates the synergy between the eROSITA and HSC surveys in preparation for the forthcoming first-year eROSITA cluster cosmology.

DOI： 10.1051/0004-6361/202141755

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Context. The eFEDS survey is a proof-of-concept mini-survey designed to demonstrate the survey science capabilities of SRG/eROSITA. It covers an area of 140 deg2 where ~540 galaxy clusters have been detected out to a redshift of 1.3. The eFEDS field is partly embedded in the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) S19A data release, which covers ~510 deg2, containing approximately 36 million galaxies. This galaxy catalogue has been used to construct a sample of ~180 shear-selected galaxy clusters. The common area to both surveys covers about 90 deg2, making it an ideal region to study galaxy clusters selected in different ways. Aims. The aim of this work is to investigate the effects of selection methods in the galaxy cluster detection by comparing the X-ray selected, eFEDS, and the shear-selected, HSC-SSP S19A, galaxy cluster samples. There are 25 shear-selected clusters in the eFEDS fooprint. Methods. The relation between X-ray bolometric luminosity and weak-lensing mass is investigated (Lbol - M relation), comparing this relation derived from a shear-selected cluster sample to the relation obtained from an X-ray selected sample. Moreover, the dynamical state of the shear-selected clusters is investigated and compared to the X-ray selected sample using X-ray morphological parameters and galaxy distribution. Results. The normalisation of the Lbol â ? ? M relation of the X-ray selected and shear-selected samples is consistent within 1Ï ? -. Moreover, the dynamical state and merger fraction of the shear-selected clusters is not different from the X-ray selected ones. Four shear-selected clusters are undetected in X-rays. A close inspection reveals that one is the result of projection effects, while the other three have an X-ray flux below the ultimate eROSITA detection limit. Finally, 43% of the shear-selected clusters lie in superclusters. Conclusions. Our results indicate that the scaling relation between X-ray bolometric luminosity and true cluster mass of the shear-selected cluster sample is consistent with the eFEDS sample. There is no significant population of X-ray underluminous clusters, indicating that X-ray selected cluster samples are complete and can be used as an accurate cosmological probe.

DOI： 10.1051/0004-6361/202142214

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Context. In 2019, the eROSITA telescope on board the Russian-German satellite Spectrum-Roentgen-Gamma (SRG) began to perform a deep all-sky X-ray survey with the aim of identifying ~100 000 clusters and groups over the course of four years. As part of its performance verification phase, a ~140 deg2 survey, called eROSITA Final Equatorial-Depth Survey (eFEDS), was performed. With a depth typical of the all-sky survey after four years, it allows tests of tools and methods as well as improved predictions for the all-sky survey. Aims. As part of this effort, a catalog of 542 X-ray selected galaxy group and cluster candidates was compiled. In this paper we present the optical follow-up, with the aim of providing redshifts and cluster confirmation for the full sample. Furthermore, we aim to provide additional information on the dynamical state, richness, and optical center of the clusters. Finally, we aim to evaluate the impact of optical cluster confirmation on the purity and completeness of the X-ray selected sample. Methods. We used optical imaging data from the Hyper Suprime-Cam Subaru Strategic Program and from the Legacy Survey to identify optical counterparts to the X-ray detected cluster candidates. We make use of the multi-component matched filter cluster confirmation tool (MCMF), as well as of the optical cluster finder CAMIRA to derive cluster redshifts and richnesses. MCMF provided the probabilities with which an optical structure would be a chance superposition with the X-ray candidate. These probabilities were used to identify the best optical counterpart as well as to confirm an X-ray candidate as a cluster. The impact of this confirmation process on catalog purity and completeness was estimated using optical to X-ray scaling relations as well as simulations. The resulting catalog was furthermore matched with public group and cluster catalogs. Optical estimators of the cluster dynamical state were constructed based on density maps of the red-sequence galaxies at the cluster redshift. Results. By providing redshift estimates for all 542 candidates, we construct an optically confirmed sample of 477 clusters and groups with a residual contamination of 6%. Of these, 470 (98.5%) are confirmed using MCMF, and 7 systems are added through cross-matching with spectroscopic group catalogs. Using observable-to-observable scaling and the applied confirmation threshold, we predict that 8 ± 2 real systems have been excluded with the MCMF cut required to build this low-contamination sample. This number agrees well with the 7 systems found through cross-matching that were not confirmed with MCMF. The predicted redshift and mass distribution of this catalog agree well with simulations. Thus, we expect that these 477 systems include >99% of all true clusters in the candidate list. Using an MCMF-independent method, we confirm that the catalog contamination of the confirmed subsample is 6 ± 3%. Application of the same method to the full candidate list yields 17 ± 3%, consistent with estimates coming from the fraction of confirmed systems of ~17% and with expectations from simulations of ~20%. We also present a sample of merging cluster candidates based on the derived estimators of the cluster dynamical state.

DOI： 10.1051/0004-6361/202141123

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

We present the results obtained from the full-shape cosmology analysis of the redshift-space power spectra for four galaxy samples of the SDSS-III BOSS DR12 galaxy catalog over 0.2 < z < 0.75. For the theoretical template, we use an emulator that was built from an ensemble set of N-body simulations, which enables fast and accurate computation of the redshift-space power spectrum of "halos." Combining with the halo occupation distribution to model the galaxy-halo connection, we can compute the redshift-space power spectrum of BOSS-like galaxies in less than a CPU second, for an input model under flat Lambda CDM cosmology. In our cosmology inference, we use the monopole, quadrupole, and hexadecapole moments of the redshift-space power spectrum and include seven nuisance parameters, with broad priors, to model uncertainties in the galaxy-halo connection for each galaxy sample, but do not use any information on the abundance of galaxies. We demonstrate a validation of our analysis pipeline using the mock catalogs of BOSS-like galaxies, generated using different recipes of the galaxy-halo connection and including the assembly bias effect. Assuming weak priors on cosmological parameters, except for the BBN prior on Omega(b)h(2) and the CMB prior on n(s), we show that our model well reproduces the BOSS power spectra. Including the power-spectrum information up to k(m)(ax) = 0.25h Mpc(-1), we find Omega(m) = 0.301(-0.011)(+0.012), H-0 = 68.2 +/- 1.4 km s(-1) Mpc(-1), and sigma(8) = 0.786(-0.037)(+0.036) for the mode and 68% credible interval, after marginalization over galaxy-halo connection parameters. We find little improvement in the cosmological parameters beyond a maximum wavelength k(max) similar or equal to 0.2h Mpc(-1) due to the shot noise domination and marginalization of the galaxy-halo connection parameters. Our results are consistent with the Planck CMB results within 1 sigma statistical uncertainties.

DOI： 10.1103/PhysRevD.105.083517

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

DOI： 10.1093/pasj/psab117

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

This paper presents the third data release of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP), a wide-field multi-band imaging survey with the Subaru 8.2 m telescope. HSC-SSP has three survey layers (Wide, Deep, and UltraDeep) with different area coverages and depths, designed to address a wide array of astrophysical questions. This third release from HSC-SSP includes data from 278 nights of observing time and covers about 670 deg(2) in all five broad-band filters (grizy) at the full depth (similar to 26 mag at 5 sigma depending on filter) in the Wide layer. If we include partially observed areas, the release covers 1470 deg(2). The Deep and UltraDeep layers have similar to 80% of the originally planned integration times, and are considered done, as we have slightly changed the observing strategy in order to compensate for various time losses. There are a number of updates in the image processing pipeline. Of particular importance is the change in the sky subtraction algorithm; we subtract the sky on small scales before the detection and measurement stages, which has significantly reduced the number of false detections. Thanks to this and other updates, the overall quality of the processed data has improved since the previous release. However, there are limitations in the data (for example, the pipeline is not optimized for crowded fields), and we encourage the user to check the quality assurance plots as well as a list of known issues before exploiting the data. The data release website is < https://hsc-release.mtk.nao.ac.jp >.

DOI： 10.1093/pasj/psab122

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We present the galaxy shear catalog that will be used for the three-year cosmological weak gravitational lensing analyses using data from the Wide layer of the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP) Survey. The galaxy shapes are measured from the i-band imaging data acquired from 2014 to 2019 and calibrated with image simulations that resemble the observing conditions of the survey based on training galaxy images from the Hubble Space Telescope in the COSMOS region. The catalog covers an area of 433.48 deg(2) of the northern sky, split into six fields. The mean i-band seeing is 0 ''.59. With conservative galaxy selection criteria (e.g., i-band magnitude brighter than 24.5), the observed raw galaxy number density is 22.9 arcmin(-2), and the effective galaxy number density is 19.9 arcmin(-2). The calibration removes the galaxy property-dependent shear estimation bias to the level vertical bar delta m vertical bar < 9 x 10(-3). The bias residual delta m shows no dependence on redshift in the range 0 < z <= 3. We define the requirements for cosmological weak-lensing science for this shear catalog, and quantify potential systematics in the catalog using a series of internal null tests for systematics related to point-spread function modelling and shear estimation. A variety of the null tests are statistically consistent with zero or within requirements, but (i) there is evidence for PSF model shape residual correlations; and (ii) star-galaxy shape correlations reveal additive systematics. Both effects become significant on >1 degrees scales and will require mitigation during the inference of cosmological parameters using cosmic shear measurements.

DOI： 10.1093/pasj/psac006

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing Ltd  

The faint-end slope of the quasar luminosity function at z similar to 6 and its implication on the role of quasars in reionizing the intergalactic medium at early times has been an outstanding problem for some time. The identification of faint high-redshift quasars with luminosities of <10(44.5) erg s(-1) is challenging. They are rare (few per square degree), and the separation of these unresolved quasars from late-type stars and compact star-forming galaxies is difficult from ground-based observations alone. In addition, source confusion becomes significant at >25 mag, with similar to 30% of sources having their flux contaminated by foreground objects when the seeing resolution is similar to 0 ''.7. We mitigate these issues by performing a pixel-level joint processing of ground and space-based data from Subaru/Hyper-SuprimeCam (HSC) and Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS). We create a deconfused catalog over the 1.64 deg(2) of the COSMOS field, after accounting for spatial varying point-spread functions and astrometric differences between the two data sets. We identify twelve low-luminosity (M ( UV ) similar to -21 mag) z > 6 quasar candidates through (i) their red color measured between ACS/F814W and HSC/i band and (ii) their compactness in the space-based data. Nondetections of our candidates in Hubble DASH data argues against contamination from late-type stars. Our constraints on the faint end of the quasar luminosity function at z similar to 6.4 suggest a negligibly small contribution to reionization compared to the star-forming galaxy population. The confirmation of our candidates and the evolution of number density with redshift could provide better insights into how supermassive galaxies grew in the first billion years of cosmic time.

DOI： 10.3847/1538-4357/ac59b3

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/stab3586

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We utilize the galaxy shape catalogue from the first-year data release of the Subaru Hyper Suprime-Cam (HSC) survey to study the dark matter content of galaxy groups in the Universe using weak lensing. We use galaxy groups from the Galaxy Mass and Assembly galaxy survey in approximately 100 sq. degrees of the sky that overlap with the HSC survey as lenses. We restrict our analysis to the 1587 groups with at least five members. We divide these groups into six bins each of group luminosity and group member velocity dispersion and measure the lensing signal with a signal-to-noise ratio of 55 and 51 for these two different selections, respectively. We use a Bayesian halo model framework to infer the halo mass distribution of our groups binned in the two different observable properties and constrain the power-law scaling relation and the scatter between mean halo masses and the two-group observable properties. We obtain a 5 per cent constraint on the amplitude of the scaling relation between halo mass and group luminosity with < M > = (0.81 +/- 0.04) x 10(14) h(-1) M-circle dot for L-grp = 10(11)(.5)h(-2) L-circle dot,L- and a power-law index of alpha = 1.01 +/- 0.07. We constrain the amplitude of the scaling relation between halo mass and velocity dispersion to be < M > = (0.93 +/- 0.05) x 10(14) h(-1) M-circle dot for sigma = 500 km s(-1) and a power-law index to be alpha = 1.52 +/- 0.10. However, these scaling relations are sensitive to the exact cuts applied to the number of group members. Comparisons with similar scaling relations from the literature show that our results are consistent and have significantly reduced errors.

DOI： 10.1093/mnras/stac007

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/stab2764

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We simulate the scientific performance of the Nancy Grace Roman Space Telescope High Latitude Survey (HLS) on dark energy and modified gravity. The 1.6-yr HLS Reference survey is currently envisioned to image 2000 deg(2) in multiple bands to a depth of similar to 26.5 in Y, J, H and to cover the same area with slit-less spectroscopy beyond z = 3. The combination of deep, multiband photometry and deep spectroscopy will allow scientists to measure the growth and geometry of the Universe through a variety of cosmological probes (e.g. weak lensing, galaxy clusters, galaxy clustering, BAO, Type Ia supernova) and, equally, it will allow an exquisite control of observational and astrophysical systematic effects. In this paper, we explore multiprobe strategies that can be implemented, given the telescope's instrument capabilities. We model cosmological probes individually and jointly and account for correlated systematics and statistical uncertainties due to the higher order moments of the density field. We explore different levels of observational systematics for the HLS survey (photo-z and shear calibration) and ultimately run a joint likelihood analysis in N-dim parameter space. We find that the HLS reference survey alone can achieve a standard dark energy FoM of >300 when including all probes. This assumes no information from external data sets, we assume a flat universe however, and includes realistic assumptions for systematics. Our study of the HLS reference survey should be seen as part of a future community-driven effort to simulate and optimize the science return of the Roman Space Telescope.

DOI： 10.1093/mnras/stab1762

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We explore synergies between the Nancy Grace Roman Space Telescope and the Vera Rubin Observatory's Legacy Survey of Space and Time (LSST). Specifically, we consider scenarios where the currently envisioned survey strategy for the Roman Space Telescope's High Latitude Survey (HLS reference), i.e. 2000 deg(2) in four narrow photometric bands is altered in favour of a strategy of rapid coverage of the LSST area (to full LSST depth) in one band. We find that in only five months, a survey in the W-band can cover the full LSST survey area providing high-resolution imaging for >95 per cent of the LSST Year 10 gold galaxy sample. We explore a second, more ambitious scenario where the Roman Space Telescope spends 1.5 yr covering the LSST area. For this second scenario, we quantify the constraining power on dark energy equation-of-state parameters from a joint weak lensing and galaxy clustering analysis. Our survey simulations are based on the Roman Space Telescope exposure-time calculator and redshift distributions from the CANDEIS catalogue. Our statistical uncertainties account for higher order correlations of the density field, and we include a wide range of systematic effects, such as uncertainties in shape and redshift measurements, and modelling uncertainties of astrophysical systematics, such as galaxy bias, intrinsic galaxy alignment, and baryonic physics. We find a significant increase in constraining power for the joint LSST + HLS wide survey compared to LSST Y10 (FoM(HLSwide) = 2.4 FoM(LSST)) and compared to LSST + HIS (FoM(HLSwide) = 5.5 FOMHLSref).

DOI： 10.1093/mnras/stab533

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing Ltd  

Using photometrically selected galaxies from the Hyper Suprime-Cam (HSC) survey, we measure the stellar-mass density profiles for satellite galaxies around isolated central galaxies (ICGs) from SDSS/DR7 at z similar to 0.1. By stacking HSC images, we also measure the projected stellar-mass density profiles for ICGs and their stellar halos. The total mass distributions are further measured from HSC weak-lensing signals. ICGs dominate within similar to 0.15 times the halo virial radius (0.15 R (200)). The stellar mass versus total mass fractions drop with the increase in projected distance up to similar to 0.15 R (200), beyond which they are less than 1% while staying almost constant. The integrated stellar mass in satellites is proportional to the virial mass of the host halo, M (200), for ICGs more massive than 10(10.5) M (circle dot), i.e., M (*,sat) proportional to M (200), whereas the relation between the stellar mass of ICGs + stellar halos and M (200) is close to M*,ICG+diffuse proportional to M2001/2 M (circle dot), the change in M (200) is much slower with the decrease in M (*,ICG+diffuse). At fixed stellar mass, red ICGs are hosted by more massive dark matter halos and have more satellites. At M (200) similar to 10(12.7) M (circle dot), both M (*,sat) and the fraction of stellar mass in satellites versus total stellar mass, f (sat), tend to be marginally higher around blue ICGs. f (sat) increases with the increase in both M (*,ICG+diffuse) and M (200), and scales more linearly with M (200). We provide best-fitting relations to M (200) versus M (*,ICG+diffuse), M (*,sat) or M (*,ICG+diffuse) + M (*,sat), and to f (sat) versus M (200) or M (*,ICG+diffuse), for red and blue ICGs separately.

DOI： 10.3847/1538-4357/ac0e38

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We use the Hyper Suprime-Cam Subaru Strategic Program S19A shape catalog to construct weak lensing shear-selected cluster samples. From aperture mass maps covering ∼510 deg2 created using a truncated Gaussian filter, we construct a catalog of 187 shear-selected clusters that correspond to mass map peaks with signal-to-noise ratio larger than 4.7. Most of the shear-selected clusters have counterparts in optically selected clusters, from which we estimate the purity of the catalog to be higher than 95%. The sample can be expanded to 418 shear-selected clusters with the same signal-to-noise ratio cut by optimizing the shape of the filter function and by combining weak lensing mass maps created with several different background galaxy selections. We argue that dilution and obscuration effects of cluster member galaxies can be mitigated by using background source galaxy samples and adopting a filter function with its inner boundary larger than about 2'. The large samples of shear-selected clusters that are selected without relying on any baryonic tracer are useful for detailed studies of cluster astrophysics and cosmology.

DOI： 10.1093/pasj/psab047

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Astrophysical Journal, Supplement Series  

We present a catalog of 4195 optically confirmed Sunyaev–Zel’dovich (SZ) selected galaxy clusters detected with signal-to-noise ratio >4 in 13,211 deg2 of sky surveyed by the Atacama Cosmology Telescope (ACT). Cluster candidates were selected by applying a multifrequency matched filter to 98 and 150 GHz maps constructed from ACT observations obtained from 2008 to 2018 and confirmed using deep, wide-area optical surveys. The clusters span the redshift range 0.04 < z < 1.91 (median z = 0.52). The catalog contains 222 z > 1 clusters, and a total of 868 systems are new discoveries. Assuming an SZ signal versus mass-scaling relation calibrated from X-ray observations, the sample has a 90% completeness mass limit of M500c > 3.8 × 1014 Me, evaluated at z = 0.5, for clusters detected at signal-to-noise ratio >5 in maps filtered at an angular scale of 2 4. The survey has a large overlap with deep optical weak-lensing surveys that are being used to calibrate the SZ signal mass-scaling relation, such as the Dark Energy Survey (4566 deg2), the Hyper Suprime-Cam Subaru Strategic Program (469 deg2), and the Kilo Degree Survey (825 deg2). We highlight some noteworthy objects in the sample, including potentially projected systems, clusters with strong lensing features, clusters with active central galaxies or star formation, and systems of multiple clusters that may be physically associated. The cluster catalog will be a useful resource for future cosmological analyses and studying the evolution of the intracluster medium and galaxies in massive clusters over the past 10 Gyr.

DOI： 10.3847/1538-4365/abd023

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We conduct a comprehensive and statistical study of the luminosity functions (LFs) for satellite galaxies, by counting photometric galaxies from HSC, DECaLS, and SDSS around isolated central galaxies (ICGs) and paired galaxies from the SDSS/DR7 spectroscopic sample. Results of different surveys show very good agreement. The satellite LFs can be measured down to M-V similar to -10, and for central primary galaxies as small as 8.5 < log(10)M(*)/M-circle dot < 9.2 and 9.2 < log(10)M(*)/M-circle dot < 9.9, which implies there are on average 3-8 satellites with M-V < -10 around LMC-mass ICGs. The bright end cutoff of satellite LFs and the satellite abundance are both sensitive to the magnitude gap between the primary and its companions, indicating galaxy systems with larger magnitude gaps are on average hosted by less massive dark matter haloes. By selecting primaries with stellar mass similar to our Milky Way (MW), we discovered that (i) the averaged satellite LFs of ICGs with different magnitude gaps to their companions and of galaxy pairs with different colour or colour combinations all show steeper slopes than the MW satellite LF; (ii) there are on average more satellites with -15 < M-V < -10 than those in our MW; (iii) there are on average 1.5 to 2.5 satellites with M-V < -16 around ICGs, consistent with our MW; (iv) even after accounting for the large scatter predicted by numerical simulations, the MW satellite LF is uncommon at M-V > -12. Hence, the MW and its satellite system are statistically atypical of our sample of MW-mass systems. In consequence, our MW is not a good representative of other MW-mass galaxies. Strong cosmological implications based on only MW satellites await additional discoveries of fainter satellites in extra-galactic systems. Interestingly, the MW satellite LF is typical among other MW-mass systems within 40 Mpc in the local Universe, perhaps implying the Local Volume is an underdense region.

DOI： 10.1093/mnras/staa3495

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP PUBLISHING LTD  

We apply the Fourier Power Function Shapelets (FPFS) shear estimator to the first-year data of the Hyper Suprime-Cam survey to construct a shape catalog. The FPFS shear estimator has been demonstrated to have a multiplicative bias less than 1% in the absence of blending, regardless of complexities of galaxy shapes, smears of point spread functions (PSFs), and contamination from noise. The blending bias is calibrated with realistic image simulations, which include the impact of neighboring objects, using the COSMOS Hubble Space Telescope images. Here we carefully test the influence of PSF model residual on the FPFS shear estimation and the uncertainties in the shear calibration. Internal null tests are conducted to characterize potential systematics in the FPFS shape catalog, and the results are compared with those measured using a catalog where the shapes were estimated using the re-Gaussianization algorithms. Furthermore, we compare various weak-lensing measurements between the FPFS shape catalog and the re-Gaussianization shape catalog and conclude that the weak-lensing measurements between these two shape catalogs are consistent with each other within the statistical uncertainty.

DOI： 10.3847/1538-4365/abbad1

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

We assess the performance of a perturbation theory inspired method for inferring cosmological parameters from the joint measurements of galaxy-galaxy weak lensing (Δς) and the projected galaxy clustering (wp). To do this, we use a wide variety of mock galaxy catalogs constructed based on a large set of N-body simulations that mimic the Subaru HSC-Y1 and SDSS galaxies and apply the method to the mock signals to address whether to recover the underlying true cosmological parameters in the mocks. We find that, as long as the appropriate scale cuts, 12 and 8h-1 Mpc for Δς and wp, respectively, are adopted, a "minimal-bias"model using the linear bias parameter b1 alone and the nonlinear matter power spectrum can recover the true cosmological parameters (here focused on ωm and σ8) to within the 68% credible interval, for all the mocks we study, including one in which an assembly bias effect is implemented. This is as expected if physical processes inherent in galaxy formation and evolution are confined to local, small scales below the scale cut and thus implies that real-space observables have an advantage in filtering out the impact of small-scale nonlinear effects in parameter estimation, compared to their Fourier-space counterparts. In addition, we find that a theoretical template including the higher-order bias contributions such as nonlinear bias parameter (b2) does not improve the cosmological constraints, but rather leads to a larger parameter bias compared to the baseline b1 method. Another nontrivial finding is that the cosmological parameters are not necessarily recovered, even when the model prediction is used as the input mock signals, as a consequence of marginalization or projection of asymmetric posterior distributions in a multidimensional parameter space, such as the case of the "banana-shaped"distribution in the (ωm,σ8) plane. We also study the performance of alternative observables, ϒ or Y statistic, where the same scale cut for both the weak lensing and the galaxy clustering can be employed thanks to their same sensitivity to the Fourier modes, but do not find a promising advantage of these statistics over the fiducial observables {Δς,wp}.

DOI： 10.1103/PhysRevD.102.083520

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We report the weak lensing measurement of filaments between Sloan Digital Sky
Survey (SDSS) III/Baryon Oscillation Spectroscopic Survey (BOSS) CMASS galaxy
pairs at $z\sim0.55$, using the Subaru Hyper Suprime-Cam (HSC) first-year
galaxy shape catalogue. Despite of the small overlap of $140$ deg$^2$ between
these surveys we detect the filament lensing signal at 3.9$\sigma$
significance, which is the highest signal-to-noise lensing measurement of
filaments between galaxy-scale halos at this redshift range. We derive a
theoretical prediction and covariance using mock catalogues based on full-sky
ray-tracing simulations. We find that the intrinsic scatter of filament
properties and the fluctuations in large scale structure along the
line-of-sight are the primary component of the covariance and the intrinsic
shape noise from source galaxies no longer limits our lensing measurement. This
fact demonstrates the statistical power of the HSC survey due to its deep
observations and high number density of source galaxies. Our result is
consistent with the theoretical prediction and supports the "thick" filament
model. As the HSC survey area increases, we will be able to study detailed
filament properties such as the dark matter distributions and redshift
evolution of filaments.

DOI： 10.1093/mnras/staa1390

Web of Science

Scopus

arXiv

Other Link： http://arxiv.org/pdf/1905.08991v1

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1475-7516/2020/03/044

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/staa117

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4357/ab6bca

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psz138

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psz103

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4357/ab3719

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4357/ab2da2

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4357/ab3424

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/stz791

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4357/ab0af0

Web of Science

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

We measure cosmic weak lensing shear power spectra with the Subaru Hyper SuprimeCam (HSC) survey first-year shear catalog covering 137 deg(2) of the sky. Thanks to the high effective galaxy number density of similar to 17 arcmin(-2), even after conservative cuts such as a magnitude cut of i < 24.5 and photometric redshift cut of 0.3 <= z <= 1.5, we obtain a high-significance measurement of the cosmic shear power spectra in four tomographic redshift bins, achieving a total signal-to-noise ratio of 16 in the multipole range 300 <= l <= = 1900. We carefully account for various uncertainties in our analysis including the intrinsic alignment of galaxies, scatters and biases in photometric redshifts, residual uncertainties in the shear measurement, and modeling of the matter power spectrum. The accuracy of our power spectrummeasurement method as well as our analytic model of the covariance matrix are tested against realistic mock shear catalogs. For a flat Lambda cold dark matter model, we find S-8 = sigma(8)(Omega(m)/0.3)(alpha) = 0.800(-0.028)(+0.029) for alpha = 0.45 (S-8 = 0.780(-0.033)(+0.030) for alpha = 0.5) from our HSC tomographic cosmic shear analysis alone. In comparison with Planck cosmic microwave background constraints, our results prefer slightly lower values of S8, although metrics such as the Bayesian evidence ratio test do not show significant evidence for discordance between these results. We study the effect of possible additional systematic errors that are unaccounted for in our fiducial cosmic shear analysis, and find that they can shift the best-fit values of S-8 by up to similar to 0.6 sigma in both directions. The full HSC survey data will contain several times more area, and will lead to significantly improved cosmological constraints.

DOI： 10.1093/pasj/psz010

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/sty2420

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psy024

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4365/aaa6cb

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psy009

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/1538-4357/aaaab8

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx070

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx079

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx080

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx069

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx066

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx130

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx128

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx132

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx063

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx106

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx081

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx042

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/pasj/psx120

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.96.103525

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/MNRAS/STX1477

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.95.123512

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevLett.118.161301

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/stw3056

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1475-7516/2016/08/013

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3847/0004-637X/825/1/39

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/stw142

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevLett.116.041301

Web of Science

Scopus

PubMed

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/stv781

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/0067-0049/219/1/12

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/0004-637X/806/1/1

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/0004-637X/806/1/2

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.ascom.2015.02.002

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/0067-0049/212/1/5

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1748-0221/9/04/C04031

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/0067-0049/211/2/17

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1117/12.2056540

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/mnras/sts643

Web of Science

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1109/TNS.2012.2201169

Scopus

J-GLOBAL

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

Hyper Suprime-Cam (HSC) is an 870 Mega pixel prime focus camera for the 8.2 m Subaru telescope. The wide field corrector delivers sharp image of 0.25 arc-sec FWHM in r-band over the entire 1.5 degree (in diameter) field of view. The collimation of the camera with respect to the optical axis of the primary mirror is realized by hexapod actuators whose mechanical accuracy is few microns. As a result, we expect to have seeing limited image most of the time. Expected median seeing is 0.67 arc-sec FWHM in i-band. The sensor is a p-ch fully depleted CCD of 200 micron thickness (2048 x 4096 15 mu m square pixel) and we employ 116 of them to pave the 50 cm focal plane. Minimum interval between exposures is roughly 30 seconds including reading out arrays, transferring data to the control computer and saving them to the hard drive. HSC uniquely features the combination of large primary mirror, wide field of view, sharp image and high sensitivity especially in red. This enables accurate shape measurement of faint galaxies which is critical for planned weak lensing survey to probe the nature of dark energy. The system is being assembled now and will see the first light in August 2012.

DOI： 10.1117/12.926844

Web of Science

Scopus

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER SCIENCE BV  

Hyper Suprime-Cam (HSC) is a 1 Giga pixel CCD camera for a wide-field galaxy survey at the Subaru 8-m Telescope. It will be mounted on the prime focus of the Subaru Telescope and is scheduled to receive its first light in 2012. The primary science is to conduct a weak lensing survey over similar to 2,000 square degrees. The HSC has a 1.5-degree-diameter field of view, 7 times larger than that of its predecessor Suprime-Cam. It consists of a large corrector lens system and a focal plane equipped with 116 pieces of 2k x 4k fully depleted CCDs. Combined with the superb image quality and large aperture of the Subaru telescope, the survey using HSC can cover a cosmological volume and reach the limiting magnitude of at least one magnitude fainter than the other surveys conducted using 4-m class telescopes. The readout electronics of the HSC consist of two parts: one is the analog front-end electronics (FEE) and the other is the digital back-end electronics (BEE). The FEE is placed in a vacuum dewar together with the CCDs, and processes the analog CCD signal into 16-bit digital data. The BEE is small and light enough to be integrated into the camera unit, and employs three links of Gigabit Ethernet to readout a 2.3-GByte single exposure within 10 seconds at fast readout operation. The readout noise from the electronics is smaller than that from CCDs. (C) 2012 Published by Elsevier B.V. Selection and/or peer review under responsibility of the organizing committee for TIPP 11.

DOI： 10.1016/j.phpro.2012.03.742

Web of Science

Scopus

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

Hyper Suprime-Cam (HSC) employs 116 pieces of 2kx4k fully-depleted CCD with a total of 464 signal outputs to cover the 1.5 degrees diameter field of view. The readout electronics was designed to achieve similar to 5 e of the readout noise and 150000 e of the fullwell capacity with 20 seconds readout time. Although the image size exceeds 2G Bytes, the readout electronics supports the 10 seconds readout time for the entire CCDs continuously. All of the readout electronics and the CCDs have already been installed in the camera dewar. The camera has been built with equipment such as coolers and an ion pump. We report the readout performance of all channels of the electronics extracted from the recent test data.

DOI： 10.1117/12.925764

Web of Science

Scopus

Event date： 2024.11

Language：English   Presentation type：Oral presentation (general)  

Event date： 2024.8

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Event date： 2024.7

Presentation type：Oral presentation (general)  

Event date： 2024.6

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Event date： 2024.4

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2024.2

Language：English   Presentation type：Oral presentation (general)  

Event date： 2023.12

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Event date： 2023.12

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Event date： 2023.11 - 2023.12

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.11

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.11

Language：English   Presentation type：Oral presentation (general)  

Event date： 2023.10 - 2023.11

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.9

Language：English   Presentation type：Oral presentation (general)  

Event date： 2023.7 - 2023.8

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.6

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.5

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.5

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.4

Presentation type：Oral presentation (invited, special)  

Event date： 2023.4

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2023.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Nationao Astronomical Observatory of Japan   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：立教大学   Country：Japan  

Event date： 2023.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Kavli IPMU, University of Tokyo   Country：Japan  

Event date： 2023.2

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagoya University   Country：Japan  

Event date： 2023.1 - 2023.2

Language：English   Presentation type：Oral presentation (general)  

Venue：Nationao Astronomical Observatory of Japan   Country：Japan  

Event date： 2022.12

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：コラッセ福島   Country：Japan  

Event date： 2022.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：YITP, Kyoto University   Country：Japan  

Event date： 2022.11 - 2022.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Kavli IPMU, University of Tokyo   Country：Japan  

Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (keynote)  

Venue：名古屋大学   Country：Japan  

Event date： 2022.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagoya University   Country：Japan  

Event date： 2022.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Kyoto University   Country：Japan  

Event date： 2022.10

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：KIAS   Country：Korea, Republic of  

Event date： 2022.10

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：KIAS   Country：Korea, Republic of  

Event date： 2022.9

Presentation type：Oral presentation (invited, special)  

Event date： 2022.7

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Sexten Center for Astrophysics, Sesto   Country：Italy  

Event date： 2022.7

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Sexten Center for Astrophysics, Sesto   Country：Italy  

Event date： 2022.7

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Cambridge University   Country：United Kingdom  

Event date： 2022.6

Language：English   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：Osaka University   Country：Japan  

Event date： 2022.1

Presentation type：Oral presentation (general)  

Event date： 2022.1

Language：English   Presentation type：Oral presentation (general)  

Event date： 2021.12

Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2021.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Online  

Event date： 2021.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Online  

Event date： 2021.11

Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2021.10

Presentation type：Oral presentation (general)  

Venue：Paris & Online   Country：France  

Event date： 2021.10

Language：English   Presentation type：Oral presentation (general)  

Event date： 2021.9

Presentation type：Oral presentation (invited, special)  

Venue：オンライン  

Event date： 2021.9

Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2021.3

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2021.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Online  

Event date： 2021.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Online  

Event date： 2020.12

Language：English   Presentation type：Oral presentation (general)  

Event date： 2020.12

Event date： 2020.9

Language：English   Presentation type：Oral presentation (general)  

Event date： 2020.9

Event date： 2020.8

Language：English   Presentation type：Oral presentation (invited, special)  

Event date： 2020.8

Event date： 2020.2

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2020.2

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2019.12

Language：English   Presentation type：Oral presentation (general)  

Event date： 2019.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2019.10

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：千葉大学   Country：Japan  

Event date： 2019.10

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：千葉大学   Country：Japan  

Event date： 2019.10

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：千葉大学   Country：Japan  

Event date： 2019.10

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：京都大学   Country：Japan  

Event date： 2019.10

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：京都大学   Country：Japan  

Event date： 2019.10

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：京都大学   Country：Japan  

Event date： 2019.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2019.5

Presentation type：Oral presentation (general)  

Venue：University of New South Wales, Sydney, Australia   Country：Australia  

Event date： 2019.4

Presentation type：Oral presentation (invited, special)  

Venue：Nagoya University, Nagoya   Country：Japan  

Event date： 2019.3

Presentation type：Oral presentation (general)  

Venue：ASIAA, Taipei, Taiwan   Country：Taiwan, Province of China  

Event date： 2019.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Yukawa Institute, Kyoto, Japan  

Event date： 2019.1

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：University of California, Berkeley, USA  

Event date： 2018.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Nagoya University, Nagoya  

Event date： 2018.11

Language：English   Presentation type：Oral presentation (general)  

Event date： 2018.11

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：京都産業大学、京都  

Event date： 2018.10

Language：English   Presentation type：Oral presentation (general)  

Venue：Max Planck Institute for Astrophysics, Garching, Germany  

Event date： 2018.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Lorentz Center, Leiden, Netherland  

Event date： 2018.8

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：国立天文台、東京  

Event date： 2018.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Pasadena Convention Center, Pasadena, California, USA  

Event date： 2018.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Shanghai Jiao Tong University, Shanghai, China  

Event date： 2018.3

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Stanford University, Palo Alto, CA, USA  

Event date： 2017.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Brown University, Providence, RI, USA   Country：United States  

Event date： 2017.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Harvard University, Cambridge, MA, USA   Country：United States  

Event date： 2017.1

Presentation type：Oral presentation (general)  

Venue：Grapevine, TX, USA   Country：United States  

Language：English   Presentation type：Oral presentation (general)  

Venue：University of New South Wales, Sydney, Australia  

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Nagoya University, Nagoya  

Language：English   Presentation type：Oral presentation (general)  

Venue：ASIAA, Taipei, Taiwan  

Language：English   Presentation type：Oral presentation (general)  

Venue：Grapevine, TX, USA  

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other 

Author：Other