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arXiv · astro-ph/0607450

Photometric Redshifts in the IRAC Shallow Survey

M. Brodwin·M. J. I. Brown·M. L. N. Ashby·C. Bian·K. Brand·A. Dey·P. R. Eisenhardt·D. J. Eisenstein·A. H. Gonzalez·J. -S. Huang·B. T. Jannuzi·C. S. Kochanek·E. McKenzie·M. A. Pahre·H. A. Smith·B. T. Soifer·S. A. Stanford·D. Stern·R. J. Elston
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Abstract

Accurate photometric redshifts are calculated for nearly 200,000 galaxies to a 4.5 micron flux limit of ~13 uJy in the 8.5 deg^2 Spitzer/IRAC Shallow survey. Using a hybrid photometric redshift algorithm incorporating both neural-net and template-fitting techniques, calibrated with over 15,000 spectroscopic redshifts, a redshift accuracy of σ= 0.06(1+z) is achieved for 95% of galaxies at 0 1) galaxy clusters. We present one such spectroscopically confirmed cluster at =1.24, ISCS J1434.5+3427. Finally, we present a measurement of the 4.5 micron-selected galaxy redshift distribution.

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M. Brodwin, M. J. I. Brown, M. L. N. Ashby, C. Bian, K. Brand, A. Dey, P. R. Eisenhardt, D. J. Eisenstein, A. H. Gonzalez, J. -S. Huang, B. T. Jannuzi, C. S. Kochanek, E. McKenzie, M. A. Pahre, H. A. Smith, B. T. Soifer, S. A. Stanford, D. Stern, R. J. Elston. 2006-07-19. Photometric Redshifts in the IRAC Shallow Survey. https://doi.org/10.1086/507838

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