Evidence for a z < 8 Origin of the Source-subtracted Near-Infrared Background


Thompson RI, Eisenstein D, Fan X, Rieke M, Kennicutt RC. Evidence for a z < 8 Origin of the Source-subtracted Near-Infrared Background. The Astrophysical Journal. 2007;666 :658-662.

Date Published:

September 1, 200


This paper extends our previous fluctuation analysis of thenear-infrared background at 1.6 μm to the 1.1 μm (F110W) image ofthe Hubble Ultra Deep Field. When all detectable sources are removed,the ratio of fluctuation power in the two images is consistent with theratio expected for faint, z<8, sources, and is inconsistent with theexpected ratio for galaxies with z>8. We also use numericallyredshifted model galaxy spectral energy distributions for 50 and 10 Myrold galaxies to predict the expected fluctuation power at 3.6 and 4.5μm to compare with recent Spitzer observations. The predictedfluctuation power for galaxies at z=0-12 matches the observed Spitzerfluctuation power, while the predicted power for z>13 galaxies ismuch higher than the observed values. As was found in the 1.6 μm(F160W) analysis, the fluctuation power in the source-subtracted F110Wimage is 2 orders of magnitude below the power in the image with allsources present. This leads to the conclusion that the 0.8-1.8 μmnear-infrared background is due to resolved galaxies in the redshiftrange z<8, with the majority of power in the redshift range of0.5-1.5.