The splashback radius of optically selected clusters with Subaru HSC Second Public Data Release

Abstract Recent constraints on the splashback radius around optically selected galaxy clusters from the redMaPPer cluster-finding algorithm in the literature have shown that the observed splashback radius is ${\sim}20\%$ smaller than that predicted by N-body simulations. We present analyses on the splashback features around ∼ 3000 optically selected galaxy clusters detected by the independent cluster-finding algorithm CAMIRA over a wide redshift range of 0.1 < zcl < 1.0 from the second public data release of the Hyper Suprime-Cam (HSC) Subaru Strategic Program covering ∼427 deg2 for the cluster catalog. We detect the splashback feature from the projected cross-correlation measurements between the clusters and photometric galaxies over the wide redshift range, including for high-redshift clusters at 0.7 < zcl < 1.0, thanks to deep HSC images. We find that constraints from red galaxy populations only are more precise than those without any color cut, leading to 1σ precisions of ${\sim}15\%$ at 0.4 < zcl < 0.7 and 0.7 < zcl < 1.0. These constraints at 0.4 < zcl < 0.7 and 0.7 < zcl < 1.0 are more consistent with the model predictions (≲1σ) than their $20\%$ smaller values as suggested by the previous studies with the redMaPPer (∼2σ). We also investigate selection effects of the optical cluster-finding algorithms on the observed splashback features by creating mock galaxy catalogs from a halo occupation distribution model, and find such effects to be sub-dominant for the CAMIRA cluster-finding algorithm. We also find that the redMaPPer-like cluster-finding algorithm induces a smaller inferred splashback radius in our mock catalog, especially at lower richness, which can well explain the smaller splashback radii in the literature. In contrast, these biases are significantly reduced when increasing its aperture size. This finding suggests that aperture sizes of optical cluster finders that are smaller than splashback feature scales can induce significant biases on the inferred location of a splashback radius.

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Survey of Gravitationally lensed Objects in HSC Imaging (SuGOHI) – V. Group-to-cluster scale lens search from the HSC–SSP Survey

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1062 ◽

2020 ◽

Vol 495 (1) ◽

pp. 1291-1310 ◽

Cited By ~ 2

Author(s):

Anton T Jaelani ◽

Anupreeta More ◽

Masamune Oguri ◽

Alessandro Sonnenfeld ◽

Sherry H Suyu ◽

...

Keyword(s):

Galaxy Clusters ◽

The Other ◽

Gravitational Lenses ◽

Full Sample ◽

Redshift Range ◽

Data Release ◽

Bona Fide ◽

Strategic Program

ABSTRACT We report the largest sample of candidate strong gravitational lenses belonging to the Survey of Gravitationally lensed Objects in HSC Imaging for group-to-cluster scale (SuGOHI-c) systems. These candidates are compiled from the S18A data release of the Hyper Suprime-Cam Subaru Strategic Program (HSC–SSP) Survey. We visually inspect ∼39 500 galaxy clusters, selected from several catalogues, overlapping with the Wide, Deep, and UltraDeep fields, spanning the cluster redshift range of 0.05 < zcl < 1.38. We discover 641 candidate lens systems, of which 536 are new. From the full sample, 47 are almost certainly bona fide lenses, 181 of them are highly probable lenses, and 413 are possible lens systems. Additionally, we present 131 lens candidates at galaxy scale serendipitously discovered during the inspection. We obtained spectroscopic follow-up of 10 candidates using the X-shooter. With this follow-up, we confirm eight systems as strong gravitational lenses. Of the remaining two, one of the sources is too faint to detect any emission, and the other has a tentative redshift close to the lens redshift, but additional arcs in this system are yet to be observed spectroscopically. Since the HSC–SSP is an ongoing survey, we expect to find ∼600 definite or probable lenses using this procedure and even more if combined with other lens finding methods.

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Large scale profiles of galaxies at z=0-2 studied by stacking the HSC SSP survey data

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316011273 ◽

2016 ◽

Vol 11 (S321) ◽

pp. 318-320

Author(s):

Mariko Kubo ◽

Masami Ouchi ◽

Takatoshi Shibuya

Keyword(s):

Survey Data ◽

Surface Brightness ◽

Large Scale ◽

High Redshift ◽

Photometric Redshifts ◽

Early Formation ◽

The Galaxy ◽

Strategic Program ◽

Galaxy Populations ◽

Using Data

AbstractWe are carrying out the study of the evolution of radial surface brightness profiles of galaxies from z = 0 to 2 by stacking analysis using data corrected by the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP). This will allow us to constrain the large scale average profiles of various galaxy populations at high redshift. From the stacking analysis of galaxies selected based on their photometric redshifts, we successfully detected the outer components of galaxies at z > 1 extending to at least ~80 kpc, which imply an early formation for the galaxy outskirts.

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Answers from the Void: VIDE and its Applications

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316010516 ◽

2014 ◽

Vol 11 (S308) ◽

pp. 524-529

Author(s):

P. M. Sutter ◽

N. Hamaus ◽

A. Pisani ◽

G. Lavaux ◽

B. D. Wandelt

Keyword(s):

Dark Matter ◽

Density Profile ◽

Statistical Information ◽

Distribution Model ◽

Density Profiles ◽

Redshift Surveys ◽

Primordial Magnetic Fields ◽

Galaxy Redshift ◽

Galaxy Populations ◽

Halo Occupation Distribution

AbstractWe discuss various applications of vide, the Void IDentification and Examination toolkit, an open-source Python/C++ code for finding cosmic voids in galaxy redshift surveys and $N$-body simulations. Based on a substantially enhanced version of ZOBOV, vide not only finds voids, but also summarizes their properties, extracts statistical information, and provides a Python-based platform for more detailed analysis, such as manipulating void catalogs and particle members, filtering, plotting, computing clustering statistics, stacking, comparing catalogs, and fitting density profiles. vide also provides significant additional functionality for pre-processing inputs: for example, vide can work with volume- or magnitude-limited galaxy samples with arbitrary survey geometries, or dark matter particles or halo catalogs in a variety of common formats. It can also randomly subsample inputs and includes a Halo Occupation Distribution model for constructing mock galaxy populations. vide has been used for a wide variety of applications, from discovering a universal density profile to estimating primordial magnetic fields, and is publicly available at http://bitbucket.org/cosmicvoids/vide\_public and http://www.cosmicvoids.net.

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Second data release of the Hyper Suprime-Cam Subaru Strategic Program

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psz103 ◽

2019 ◽

Vol 71 (6) ◽

Cited By ~ 39

Author(s):

Hiroaki Aihara ◽

Yusra AlSayyad ◽

Makoto Ando ◽

Robert Armstrong ◽

James Bosch ◽

...

Keyword(s):

Broad Band ◽

Release Site ◽

Point Sources ◽

Wide Field ◽

Public Data ◽

Partially Observed ◽

Data Release ◽

Artifact Rejection ◽

Strategic Program

Abstract This paper presents the second data release of the Hyper Suprime-Cam Subaru Strategic Program, a wide-field optical imaging survey using the 8.2 m Subaru Telescope. The release includes data from 174 nights of observation through 2018 January. The Wide layer data cover about 300 deg$^2$ in all five broad-band filters ($grizy$) to the nominal survey exposure (10 min in $gr$ and 20 min in $izy$). Partially observed areas are also included in the release; about 1100 deg$^2$ is observed in at least one filter and one exposure. The median seeing in the i-band is ${0_{.}^{\prime \prime }6}$, demonstrating the superb image quality of the survey. The Deep (26 deg$^2$) and UltraDeep (4 deg$^2$) data are jointly processed and the UltraDeep-COSMOS field reaches an unprecedented depth of $i\sim 28$ at $5 \, \sigma$ for point sources. In addition to the broad-band data, narrow-band data are also available in the Deep and UltraDeep fields. This release includes a major update to the processing pipeline, including improved sky subtraction, PSF modeling, object detection, and artifact rejection. The overall data quality has been improved, but this release is not without problems; there is a persistent deblender problem as well as new issues with masks around bright stars. The user is encouraged to review the issue list before utilizing the data for scientific explorations. All the image products as well as catalog products are available for download. The catalogs are also loaded into a database, which provides an easy interface for users to retrieve data for objects of interest. In addition to these main data products, detailed galaxy shape measurements withheld from Public Data Release 1 (PDR1) are now available to the community. The shape catalog is drawn from the S16A internal release, which has a larger area than PDR1 (160 deg$^2$). All products are available at the data release site, https://hsc-release.mtk.nao.ac.jp/.

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Subaru Hyper Suprime-Cam excavates colossal over- and under-dense structures over 360 deg2 out to z = 1

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab713 ◽

2021 ◽

Author(s):

Rhythm Shimakawa ◽

Yuichi Higuchi ◽

Masato Shirasaki ◽

Masayuki Tanaka ◽

Yen-Ting Lin ◽

...

Keyword(s):

Dimensional Space ◽

Grid Point ◽

Three Dimensional ◽

Weak Lensing ◽

Density Peaks ◽

Public Data ◽

Data Release ◽

Strategic Program ◽

Point Data ◽

Good Agreement

Abstract Subaru Strategic Program with the Hyper-Suprime Cam (HSC-SSP) has proven to be successful with its extremely-wide area coverage in past years. Taking advantages of this feature, we report initial results from exploration and research of expansive over- and under-dense structures at z = 0.3 – 1 based on the second Public Data Release where optical 5-band photometric data for ∼ eight million sources with i < 23 mag are available over ∼360 square degrees. We not only confirm known superclusters but also find candidates of titanic over- and under-dense regions out to z = 1. The mock data analysis suggests that the density peaks would involve one or more massive dark matter haloes (>1014 M⊙) of the redshift, and the density troughs tend to be empty of massive haloes over >10 comoving Mpc. Besides, the density peaks and troughs at z ≲ 0.6 are in part identified as positive and negative weak lensing signals respectively, in mean tangential shear profiles, showing a good agreement with those inferred from the full-sky weak lensing simulation. The coming extensive spectroscopic surveys will be able to resolve these colossal structures in three-dimensional space. The number density information over the entire survey field is available as grid-point data on the website of the HSC-SSP data release (https://hsc.mtk.nao.ac.jp/ssp/data-release/).

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Pre-processing of galaxies in cosmic filaments around AMASCFI clusters in the CFHTLS

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935394 ◽

2019 ◽

Vol 632 ◽

pp. A49 ◽

Cited By ~ 15

Author(s):

F. Sarron ◽

C. Adami ◽

F. Durret ◽

C. Laigle

Keyword(s):

Galaxy Clusters ◽

Spectral Energy ◽

Photometric Redshifts ◽

Star Forming ◽

Galaxy Groups ◽

Photometric Redshift ◽

Preferred Direction ◽

The Galaxy ◽

Strategic Program ◽

Galaxy Populations

Context. Galaxy clusters and groups are thought to accrete material along the preferred direction of cosmic filaments. These structures have proven difficult to detect because their contrast is low, however, and only a few studies have focused on cluster infall regions. Aims. We detect cosmic filaments around galaxy clusters using photometric redshifts in the range 0.15 < z < 0.7. We characterise galaxy populations in these structures to study the influence of pre-processing by cosmic filaments and galaxy groups on star formation quenching. Methods. We detected cosmic filaments in the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) T0007 data, focusing on regions around clusters of the AMASCFI CFHTLS cluster sample. The filaments were reconstructed with the discrete persistent structure extractor (DISPERSE) algorithm in photometric redshift slices. We show that this reconstruction is reliable for a CFHTLS-like survey at 0.15 < z < 0.7 using a mock galaxy catalogue. We split our galaxy catalogue into two populations (passive and star forming) using the LePhare spectral energy density fitting algorithm and worked with two redshift bins (0.15 < z ≤ 0.4 and 0.4 < z < 0.7). Results. We showed that the AMASCFI cluster connectivity (i.e. the number of filaments that is connected to a cluster) increases with cluster mass M200. Filament galaxies outside R200 are found to be closer to clusters at low redshift, regardless of the galaxy type. Passive galaxies in filaments are closer to clusters than star-forming galaxies in the low redshift bin alone. The passive fraction of galaxies decreases with increasing clustercentric distance up to d ∼ 5 cMpc. Galaxy groups and clusters that are not located at nodes of our reconstruction are mainly found inside cosmic filaments. Conclusions. These results give clues for pre-processing in cosmic filaments that could be due to smaller galaxy groups. This trend could be further explored by applying this method to larger photometric surveys such as the Hyper Suprime-Cam Subaru Strategic Program (HSC-SPP) or Euclid.

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