Excess Clustering on Large Scales in the MegaZ DR7 Photometric Redshift Survey

AbstractWe investigate void properties inf(R)models using N-body simulations, focusing on their differences from General Relativity (GR) and their detectability. In the Hu-Sawickif(R)modified gravity (MG) models, the halo number density profiles of voids are not distinguishable from GR. In contrast, the samef(R)voids are more empty of dark matter, and their profiles are steeper. This can in principle be observed by weak gravitational lensing of voids, for which the combination of a spectroscopic redshift and a lensing photometric redshift survey over the same sky is required. Neglecting the lensing shape noise, thef(R)model parameter amplitudesfR0=10-5and 10-4may be distinguished from GR using the lensing tangential shear signal around voids by 4 and 8 σ for a volume of 1 (Gpc/h)3. The line-of-sight projection of large-scale structure is the main systematics that limits the significance of this signal for the near future wide angle and deep lensing surveys. For this reason, it is challenging to distinguishfR0=10-6from GR. We expect that this can be overcome with larger volume. The halo void abundance being smaller and the steepening of dark matter void profiles inf(R)models are unique features that can be combined to break the degeneracy betweenfR0and σ8.

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Deep ugrizY imaging and DEEP2/3 spectroscopy: a photometric redshift testbed for LSST and public release of data from the DEEP3 Galaxy Redshift Survey

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1866 ◽

2019 ◽

Vol 488 (4) ◽

pp. 4565-4584 ◽

Cited By ~ 1

Author(s):

Rongpu Zhou ◽

Michael C Cooper ◽

Jeffrey A Newman ◽

Matthew L N Ashby ◽

James Aird ◽

...

Keyword(s):

Object Size ◽

Random Forest Regression ◽

Photometric Redshifts ◽

Size Information ◽

Photometric Redshift ◽

Point Spread ◽

Spread Function ◽

Redshift Survey ◽

Galaxy Redshift ◽

Empirical Tests

ABSTRACT We present catalogues of calibrated photometry and spectroscopic redshifts in the Extended Groth Strip, intended for studies of photometric redshifts (photo-z’s). The data includes ugriz photometry from Canada–France–Hawaii Telescope Legacy Survey (CFHTLS) and Y-band photometry from the Subaru Suprime camera, as well as spectroscopic redshifts from the DEEP2, DEEP3, and 3D-HST surveys. These catalogues incorporate corrections to produce effectively matched-aperture photometry across all bands, based upon object size information available in the catalogue and Moffat profile point spread function fits. We test this catalogue with a simple machine learning-based photometric redshift algorithm based upon Random Forest regression, and find that the corrected aperture photometry leads to significant improvement in photo-z accuracy compared to the original SExtractor catalogues from CFHTLS and Subaru. The deep ugrizY photometry and spectroscopic redshifts are well suited for empirical tests of photometric redshift algorithms for LSST. The resulting catalogues are publicly available at http://d-scholarship.pitt.edu/36064/. We include a basic summary of the strategy of the DEEP3 Galaxy Redshift Survey to accompany the recent public release of DEEP3 data.

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The Las Campanas Infrared Survey. IV. The Photometric Redshift Survey and the Rest‐FrameR‐Band Galaxy Luminosity Function at 0.5 ≤ z ≤ 1.5

The Astrophysical Journal ◽

10.1086/367787 ◽

2003 ◽

Vol 586 (2) ◽

pp. 745-764 ◽

Cited By ~ 74

Author(s):

Hsiao‐Wen Chen ◽

Ronald O. Marzke ◽

Patrick J. McCarthy ◽

P. Martini ◽

R. G. Carlberg ◽

...

Keyword(s):

Luminosity Function ◽

Photometric Redshift ◽

Redshift Survey ◽

Galaxy Luminosity Function ◽

Infrared Survey

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The LABOCA survey of the Extended Chandra Deep Field-South: a photometric redshift survey of submillimetre galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2011.18795.x ◽

2011 ◽

Vol 415 (2) ◽

pp. 1479-1508 ◽

Cited By ~ 152

Author(s):

J. L. Wardlow ◽

Ian Smail ◽

K. E. K. Coppin ◽

D. M. Alexander ◽

W. N. Brandt ◽

...

Keyword(s):

Photometric Redshift ◽

Redshift Survey

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Upper Bound of 0.28 eV on Neutrino Masses from the Largest Photometric Redshift Survey

Physical Review Letters ◽

10.1103/physrevlett.105.031301 ◽

2010 ◽

Vol 105 (3) ◽

Cited By ~ 126

Author(s):

Shaun A. Thomas ◽

Filipe B. Abdalla ◽

Ofer Lahav

Keyword(s):

Upper Bound ◽

Neutrino Masses ◽

Photometric Redshift ◽

Redshift Survey

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Properties of the environment around active galactic nucleus / luminous galaxy pairs through the HSC wide survey

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psaa037 ◽

2020 ◽

Vol 72 (4) ◽

Author(s):

Yuji Shirasaki ◽

Masayuki Akiyama ◽

Yoshiki Toba ◽

Wanqiu He ◽

Tomotsugu Goto

Keyword(s):

Active Galactic Nucleus ◽

Absolute Magnitude ◽

Large Mass ◽

Dark Matter Halo ◽

Photometric Redshift ◽

Radio Detection ◽

Blue Galaxies ◽

Redshift Survey ◽

Strategic Program ◽

Blue Galaxy

Abstract We investigated the properties of active galactic nucleus (AGN) environments, particularly environments where the association of a luminous galaxy (LG) is found within 4 Mpc from an AGN with redshift 0.8–1.1. For comparison, three additional AGN environments, (namely, AGNs of all types, type 1 AGNs with X-ray and/or radio detection, and type 2 AGNs) and an environment of blue M*, the characteristic luminosity of the Schechter function, galaxies were investigated. The cross-correlation function with the surrounding galaxies was measured and compared between the AGN and blue galaxy samples. We also compared the distributions of color, absolute magnitude, and stellar mass of the galaxies around such target objects. The properties of clusters detected using surrounding galaxies selected based on a photometric redshift were examined and compared for different samples. The target AGNs were drawn from the Million Quasars (MILLIQUAS) catalog, and the blue galaxies were drawn from six redshift survey catalogs (SDSS, WiggleZ, DEEP2, VVDS, VIPERS, and PRIMUS). The galaxies used as a measure of the environment around the targets were drawn from the S18a internal data released by the Hyper Suprime-Cam Subaru Strategic Program. We found that, among the five AGN and blue galaxy samples considered, the environment of AGN–LG pairs is the most enriched with luminous galaxies. We also found an enhancement in the number of mass-selected clusters in the AGN–LG pair sample against those in the other samples. The results obtained in this study indicate that existence of multiple clusters is the major driver in the association of AGNs and LGs, rather than a single large-mass dark matter halo hosting the AGN.

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