Spitzer UltRa Faint SUrvey Program (SURFS UP). II. IRAC-detected Lyman-Break Galaxies at 6 ≲ z ≲ 10 behind Strong-lensing Clusters

Journal
Date Issued
2016
Author(s)
Huang, Kuang-Han
•
Bradač, Maruša
•
Lemaux, Brian C.
•
Ryan, R. E., Jr.
•
Hoag, Austin
•
•
Amorín, Ricardo
•
•
Brammer, Gabriel B.
•
Cain, Benjamin
•
Lubin, L. M.
•
•
Schmidt, Kasper B.
•
Schrabback, Tim
•
Treu, Tommaso
•
Gonzalez, Anthony H.
•
von der Linden, Anja
•
Knight, Robert I.
DOI
Abstract
We study the stellar population properties of the IRAC-detected 6 ≲ z ≲ 10 galaxy candidates from the Spitzer UltRa Faint SUrvey Program. Using the Lyman Break selection technique, we find a total of 17 galaxy candidates at 6 ≲ z ≲ 10 from Hubble Space Telescope images (including the full-depth images from the Hubble Frontier Fields program for MACS 1149 and MACS 0717) that have detections at signal-to-noise ratios ≥ 3 in at least one of the IRAC 3.6 and 4.5 μm channels. According to the best mass models available for the surveyed galaxy clusters, these IRAC-detected galaxy candidates are magnified by factors of ∼1.2-5.5. Due to the magnification of the foreground galaxy clusters, the rest-frame UV absolute magnitudes M1600 are between -21.2 and -18.9 mag, while their intrinsic stellar masses are between 2 × 108M☉ and 2.9 × 109M☉. We identify two Lyα emitters in our sample from the Keck DEIMOS spectra, one at zLyα = 6.76 (in RXJ 1347) and one at zLyα = 6.32 (in MACS 0454). We find that 4 out of 17 z ≳ 6 galaxy candidates are favored by z ≲ 1 solutions when IRAC fluxes are included in photometric redshift fitting. We also show that IRAC [3.6]-[4.5] color, when combined with photometric redshift, can be used to identify galaxies which likely have strong nebular emission lines or obscured active galactic nucleus contributions within certain redshift windows.
Volume
817
Issue
1
Start page
11
Uri
Url
Issn Identifier
0004-637X
Ads BibCode
2016ApJ...817...11H
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

1504.02099.pdf

Description
postprint
Size

4.49 MB

Format

Adobe PDF

Checksum (MD5)

1d579fe3358b98b1e6e3e8243343cbc3

Loading...
Thumbnail Image
Name

Huang_2016_ApJ_817_11.pdf

Description
Pdf editoriale
Size

5.98 MB

Format

Adobe PDF

Checksum (MD5)

b014249be51ec702d802ba2efdda574b