Surface Brightness Profile of Lyman-$\alpha$ Halos out to 320 kpc in HETDEX

Maja Lujan Niemeyer; Eiichiro Komatsu; Chris Byrohl; Dustin Davis; Maximilian Fabricius; Karl Gebhardt; Gary J. Hill; Lutz Wisotzki; William P. Bowman; Robin Ciardullo; Daniel J. Farrow; Steven L. Finkelstein; Eric Gawiser; Caryl Gronwall; Donghui Jeong; Martin Landriau; Chenxu Liu; Erin Mentuch Cooper; Masami Ouchi; Donald P. Schneider; Gregory R. Zeimann

doi:10.3847/1538-4357/ac5cb8

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arXiv · 2203.04826

Surface Brightness Profile of Lyman-$\alpha$ Halos out to 320 kpc in HETDEX

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Abstract

We present the median-stacked Lyman-$\alpha$ surface brightness profile of 968 spectroscopically selected Lyman-$\alpha$ emitting galaxies (LAEs) at redshifts $1.9 80\,\mathrm{kpc}$, our profile is flatter than the MUSE model. The measured profile agrees at most radii with that of galaxies in the Byrohl et al. (2021) cosmological radiative transfer simulation at $z=3$. This suggests that the surface brightness of a Lyman-$\alpha$ halo at $r\lesssim 100$ kpc is dominated by resonant scattering of Lyman-$\alpha$ photons from star-forming regions in the central galaxy, whereas at $r > 100$ kpc it is dominated by photons from galaxies in surrounding dark matter halos.

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Maja Lujan Niemeyer, Eiichiro Komatsu, Chris Byrohl, Dustin Davis, Maximilian Fabricius, Karl Gebhardt, Gary J. Hill, Lutz Wisotzki, William P. Bowman, Robin Ciardullo, Daniel J. Farrow, Steven L. Finkelstein, Eric Gawiser, Caryl Gronwall, Donghui Jeong, Martin Landriau, Chenxu Liu, Erin Mentuch Cooper, Masami Ouchi, Donald P. Schneider, Gregory R. Zeimann. 2022-03-09. Surface Brightness Profile of Lyman-$\alpha$ Halos out to 320 kpc in HETDEX. https://doi.org/10.3847/1538-4357%2Fac5cb8

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