Results 51 to 60 of about 4,678,333 (310)

PHOTOMETRIC REDSHIFTS FOR QUASARS IN MULTI-BAND SURVEYS [PDF]

The Astrophysical Journal, 2013
MLPQNA stands for Multi Layer Perceptron with Quasi Newton Algorithm and it is a machine learning method which can be used to cope with regression and classification problems on complex and massive data sets. In this paper we give the formal description of the method and present the results of its application to the evaluation of photometric redshifts ...
Brescia M., Cavuoti S., D’Abrusco R., Mercurio A., Longo G.   +4 more
openaire   +8 more sources

Bayesian inference from photometric redshift surveys [PDF]

, 2011
We show how to enhance the redshift accuracy of surveys consisting of tracers with highly uncertain positions along the line of sight. This increased redshift precision is achieved by imposing an isotropy and two-point correlation prior in a Bayesian ...
J. Jasche, B. Wandelt
semanticscholar   +1 more source

Photometric Redshifts in the IRAC Shallow Survey [PDF]

The Astrophysical Journal, 2006
14 pages, 9 Figures, 5 Tables. ApJ in press. For a version with full-resolution figures, please see http://www.astro.utoronto.ca/~brodwin/papers/0607450 ...
Brodwin, M., Brown, M. J. I., Ashby, M. L. N., Bian, C., Brand, K., Dey, A., Eisenhardt, P. R., Eisenstein, D. J., Gonzalez, A. H., Huang, J.-S., Jannuzi, B. T., Kochanek, C. S., McKenzie, E., Murray, S. S., Pahre, M. A., Smith, H. A., Soifer, B. T., Stanford, S. A., Stern, D., Elston, R. J.   +19 more
openaire   +3 more sources

Combining weak-lensing tomography and spectroscopic redshift surveys [PDF]

, 2011
Redshift space distortion (RSD) is a powerful way of measuring the growth of structure and testing General Relativity, but it is limited by cosmic variance and the degeneracy between galaxy bias b and the growth rate factor f.
Yan-Chuan Cai, G. Bernstein
semanticscholar   +1 more source

A NEW METHOD FOR THE DETERMINATION OF THE GROWTH RATE FROM GALAXY REDSHIFT SURVEYS [PDF]

, 2011
Given a redshift survey of galaxies with measurements of apparent magnitudes, we present a novel method for measuring the growth rate f(Ω) of cosmological linear perturbations.
A. Nusser, E. Branchini, M. Davis
semanticscholar   +1 more source

Optical Redshift Surveys [PDF]

Highlights of Astronomy, 1992
Redshift surveys of galaxies have been over the past decade the major source of information for studies of the large-scale structure of the Universe. Following the completion of the original CfA Redshift Survey, several groups have joined the endeavor, probing different regions of the sky to different depths in a remarkable long-term effort to study ...
openaire   +1 more source

The Unexplored Redshift Survey [PDF]

Publications of the Astronomical Society of the Pacific, 2001
Redshift surveys remain an important constraint on cosmological parameters and a key to characterizing the nature and evolution of the large‐scale distribution of galaxies. I discuss redshift surveys as a route to exploration of other issues associated with large‐scale structure including the low surface brightness universe and the links between star ...
openaire   +1 more source

The CNOC2 field galaxy redshift survey [PDF]

Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 1999
The CNOC2 field galaxy redshift survey is designed to provide measurements of the evolution of galaxies and their clustering over the redshift range 0 to 0.7. The sample is spread over four sky patches with a total area of about 1.5 square degrees. Here we report preliminary results based on two of the sky patches, and the redshift range of 0.15 to 0 ...
Carlberg, R. G., Yee, H. K. C., Morris, S. L, Lin, H., Sawicki, M., Wirth, G., Patton, D., Shepherd, C. W., Ellingson, E., Schade, D., Pritchet, C. J., Hartwick, F. D. A.   +11 more
openaire   +2 more sources

The kinetic SZ tomography with spectroscopic redshift surveys [PDF]

, 2010
The kinetic Sunyaev Zel'dovich effect (kSZ) effect is a potentially powerful probe to the missing baryons. However, the kSZ signal is overwhelmed by various contaminations and the cosmological application is hampered by loss of redshift information due ...
Jiawei Shao, Pengjie Zhang, Weipeng Lin, Y. Jing, Jun Pan   +4 more
semanticscholar   +1 more source

Correcting for Interloper Contamination in the Power Spectrum with Neural Networks

The Astrophysical Journal
Modern slitless spectroscopic surveys such as Euclid and Roman collect vast numbers of galaxy spectra, but their low signal-to-noise ratios often lead to incorrect redshift assignments when relying on a single emission line.
Marina S. Cagliari, Azadeh Moradinezhad Dizgah, Francisco Villaescusa-Navarro   +2 more
doaj   +1 more source