Selected Publications

Lyman-$\alpha$ emitters (LAEs) are a promising probe of the large-scale structure at high redshift, $z\gtrsim 2$. In particular, the Hobby-Eberly Telescope Dark Energy Experiment aims at observing LAEs at 1.9 $<z<$ 3.5 to measure the Baryon Acoustic Oscillation (BAO) scale and the Redshift-Space Distortion (RSD). However, (Zheng et al. 2011) pointed out that the complicated radiative transfer (RT) of the resonant Lyman-$\alpha$ emission line generates an anisotropic selection bias in the LAE clustering on large scales, $s\gtrsim 10\,{\rm Mpc}$. This effect could potentially induce a systematic error in the BAO and RSD measurements. Also, (Croft et al. 2016) claims an observational evidence of the effect in the Lyman-$\alpha$ intensity map, albeit statistically insignificant. We aim at quantifying the impact of the Lyman-$\alpha$ RT on the large-scale galaxy clustering in detail. For this purpose, we study the correlations between the large-scale environment and the ratio of an apparent Lyman-$\alpha$ luminosity to an intrinsic one, which we call the “observed fraction”, at $2<z<6$. We apply our Lyman-$\alpha$ RT code by post-processing the full Illustris simulations. We simply assume that the intrinsic luminosity of the Lyman-$\alpha$ emission is proportional to the star formation rate of galaxies in Illustris, yielding a sufficiently large sample of LAEs to measure the anisotropic selection bias. We find little correlations between large-scale environment and the observed fraction induced by the RT, and hence a smaller anisotropic selection bias than what was claimed by (Zheng et al. 2011). We argue that the anisotropy was overestimated in the previous work due to the insufficient spatial resolution: it is important to keep the resolution such that it resolves the high density region down to the scale of the interstellar medium, $\sim1$ physical kpc. We also find that the correlation can be further enhanced by assumptions in modeling intrinsic Lyman-$\alpha$ emission.
The impact of Lyman-α radiative transfer on large-scale clustering in the Illustris simulation, 2017

Recent Publications

. Lya RT Real Space Clustering. The impact of Lyman-α radiative transfer on large-scale clustering in the Illustris simulation, 2017.

Preprint Project

. Viscosity, pressure, and support of the gas in simulations of merging cool-core clusters. Viscosity, pressure, and support of the gas in simulations of merging cool-core clusters, 2017.

Preprint

. Constraining The Single-Degenerate Channel of Type Ia Supernovae With Stable Iron-Group Elements in SNR 3C 397. Constraining The Single-Degenerate Channel of Type Ia Supernovae With Stable Iron-Group Elements in SNR 3C 397, 2017.

Preprint

Recent Posts

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