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arXiv · 2103.03882

Probing Intra-Halo Light with Galaxy Stacking in CIBER Images

Yun-Ting Cheng·Toshiaki Arai·Priyadarshini Bangale·James J. Bock·Tzu-Ching Chang·Asantha Cooray·Richard M. Feder·Phillip M. Korngut·Dae Hee Lee·Lunjun Liu·Toshio Matsumoto·Shuji Matsuura·Chi H. Nguyen·Kei Sano·Kohji Tsumura·Michael Zemcov
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Abstract

We study the stellar halos of $0.2\lesssim z \lesssim 0.5$ galaxies with stellar masses spanning $M_*\sim 10^{10.5}$ to $10^{12}M_\odot$ (approximately $L_*$ galaxies at this redshift) using imaging data from the Cosmic Infrared Background Experiment (CIBER). A previous CIBER fluctuation analysis suggested that intra-halo light (IHL) contributes a significant portion of the near-infrared extragalactic background light (EBL), the integrated emission from all sources throughout cosmic history. In this work, we carry out a stacking analysis with a sample of $\sim$30,000 Sloan Digital Sky Survey (SDSS) photometric galaxies from CIBER images in two near-infrared bands (1.1 and 1.8 $μ$m) to directly probe the IHL associated with these galaxies. We stack galaxies in five sub-samples split by brightness, and detect an extended galaxy profile, beyond the instrument point spread function (PSF), derived by stacking stars. We jointly fit a model for the inherent galaxy light profile, plus large-scale one- and two-halo clustering to measure the extended galaxy IHL. We detect non-linear one-halo clustering in the 1.8 $μ$m band, at a level consistent with numerical simulations. Our results on the galaxy profile suggest that $\sim 50\%$ of the total galaxy light budget in our galaxy sample resides in the outskirts of the galaxies at $r > 10$ kpc. We describe this extended emission as IHL and and are able to study how this fraction evolves with cosmic time. These results are new in the near-infrared wavelength at the $L_*$ mass scale, and suggest that IHL has a significant contribution to the integrated galactic light, and to the amplitude of large-scale background fluctuations.

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Yun-Ting Cheng, Toshiaki Arai, Priyadarshini Bangale, James J. Bock, Tzu-Ching Chang, Asantha Cooray, Richard M. Feder, Phillip M. Korngut, Dae Hee Lee, Lunjun Liu, Toshio Matsumoto, Shuji Matsuura, Chi H. Nguyen, Kei Sano, Kohji Tsumura, Michael Zemcov. 2021-09-22. Probing Intra-Halo Light with Galaxy Stacking in CIBER Images. https://doi.org/10.3847/1538-4357%2Fac0f5b

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