Using the 2-MASS photometric redshift survey to optimize LIGO follow-up observations

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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EROSITA: AGN SCIENCE, BACKGROUND DETERMINATION, AND OPTICAL FOLLOW-UP SPECTROSCOPY

Acta Polytechnica ◽

10.14311/ap.2013.53.0793 ◽

2013 ◽

Vol 53 (A) ◽

pp. 793-798

Author(s):

Thomas Boller

Keyword(s):

Small Sample ◽

Scientific Success ◽

X Ray ◽

Photometric Redshift ◽

Sky Survey ◽

Extended Sources ◽

Small Sample Sizes ◽

Primary Instrument ◽

The Ideal

More than 20 years after the highly impacting ROSAT all-sky survey in the soft X-ray spectral range, we are close to the next major X-ray all/sky surveys with eROSITA. eROSITA will be the primary instrument on-board the Russian “Spectrum–Roentgen–Gamma” (SRG) satellite which will be launched from Baikonur in 2014 and placed in an L2 orbit. It will perform the first imaging all-sky survey in the medium energy X-ray range up to 10 keV with an unprecedented spectral and angular resolution. The eROSITA all sky X-ray survey will take place in a very different context than the ROSAT survey. There is now a wealth of complete, ongoing and planned surveys of the sky in broad range of wavelengths from the gamma, X-ray to the radio. A significant amount of science can be accomplished through the multi-frequency study of the eROSITA AGN and cluster sample, including optical confirmation and photometric redshift estimation of the eROSITA extended sources and AGNs. Optical spectroscopy has been, and will for the foreseeable future be, one of the main tools of astrophysics allowing studies of a large variety of astronomical objects over many fields of research. The fully capitalize on the eROSITA potential, a dedicated spectroscopic follow-up program is needed. 4MOST is the ideal instrument to secure the scientific success of the eROSITA X-ray survey and to overcome the small sample sizes together with selection biases that plagued past samples. The aim is to have the instrument commissioned in 2017, well matched to the data releases of eROSITA and Gaia. The design and implementation of the 4MOST facility simulator aimed to optimize the science output for eROSITA is described in necessary details.

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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 FLAIR–DENIS Redshift Survey

Publications of the Astronomical Society of Australia ◽

10.1071/as97125 ◽

1997 ◽

Vol 14 (1) ◽

pp. 125-126 ◽

Cited By ~ 1

Author(s):

Q. A. Parker ◽

M. Colless ◽

G. Mamon

Keyword(s):

Near Infrared ◽

Local Universe ◽

Redshift Survey ◽

Infrared Survey

AbstractThe DEep Near-Infrared Survey of the southern sky (DENIS) will produce an important by-product: a clean, complete view of the local Universe to z ∼ 0·07 for 105 galaxies. We identify the FLAIR multi-fibre system on the UKST as an extremely competitive facility to undertake follow-up spectroscopy for this sample due to the need to cover wide areas of sky and observe thousands of objects to a relatively bright (B < 17·5) magnitude.

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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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The Evolution of Galaxies and Groups in Cluster Environments at 0.3 < z < 0.6

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306006260 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 220-220

Author(s):

I. H. Li ◽

H. K. C. Yee ◽

B. C. Hsieh ◽

D. G. Gilbank ◽

M. D. Gladders

Keyword(s):

Evolutionary Status ◽

Wide Field ◽

Training Set ◽

Cluster Galaxies ◽

Galaxy Groups ◽

Photometric Redshift ◽

Probability Densities ◽

Galaxy Populations ◽

Intermediate Redshift

We investigate the dependence of galaxy populations on environment. Our samples are selected from the follow-up of Red-Sequence Cluster Survey (RCS) catalogs using wide-field BVRz' imaging for 60 intermediate redshift (0.3 < z < 0.6) clusters. Galaxy redshifts are estimated using an empirical photometric redshift technique with a training set of 3996 galaxies to z 1.4. To obtain photometric redshift probability density for each galaxy, we bootstrap the training set galaxies to estimate the fitting uncertainties and apply Monte-Carlo method to simulate galaxy magnitudes errors. In order to find galaxy groups using photometric redshift, we develop a modified friends-of-friends algorithm, ‘Probability Friends-of-Friends Algorithm (pFOF)’, where photometric redshift redshift probability densities of individual galaxies are used to determine member galaxies of a group. We calculate the red galaxy fraction to infer the evolutionary status of cluster galaxies and also for galaxies in groups selected in the same redshift space as the clusters.

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