![]() ![]() , 2013 ) and of the Lyman- α intensity map (Saito et al., in preparation) with the primary scientific goal to determine the cosmic expansion history via Baryon Acoustic Oscillations (BAOs) and the growth of structure via Redshift-Space Distortions (RSD). This allows us to precisely measure the large-scale ( ≳ 10 M p c ) clustering of LAEs ( Agrawal et al. , 2008, hereafter, HETDEX) : HETDEX will map out the three-dimensional distribution of nearly one million LAEs ( Leung et al. A remarkable example for such surveys is the Hobby-Eberly Telescope Dark Energy Experiment ( Adams et al. , 2010, 2017 ) as well as evolution of the Lyman- α luminosity function (e.g., Konno et al. These observations enable us to study galaxy clustering at somewhat small scales (e.g., Diener et al. , 2006 ), amounting to about 10 4 emitters known to date since the first detections (e.g., Cowie & Hu, 1998 Hu & McMahon, 1996 ). , 2012 ) and integral field unit spectroscopy such as MUSE (e.g., Bacon et al. In fact, more and more LAEs have been observed by surveys including narrow-band imaging (e.g., Nakajima et al. This suggests that the number density of LAEs is large enough to map out the large-scale structure of the high-redshift universe. Since LAEs are believed to be powered at least partially by ongoing star formation, they are expected to belong to a relatively low-mass and young class of actively star-forming galaxies. High-redshift z ≳ 2 galaxies with prominent Lyman- α emission ( Partridge & Peebles, 1967 ), called Lyman- α emitters (LAEs), have become the subject of intense research over the last two decades. We also find that the correlation can be further enhanced by assumptions in modeling intrinsic Lyman- α emission. 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, ∼ 1 physical kpc. ![]() Results: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. ![]() We simply assume that the intrinsic luminosity of the Lyman- α 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. Methods:We apply our Lyman- α RT code by post-processing the full Illustris simulations. For this purpose, we study the correlations between the large-scale environment and the ratio of an apparent Lyman- α luminosity to an intrinsic one, which we call the ‘observed fraction’, at 2 < z < 6. (2016) claims an observational evidence of the effect in the Lyman- α intensity map, albeit statistically insignificant.Īims:We aim at quantifying the impact of the Lyman- α RT on the large-scale galaxy clustering in detail. This effect could potentially induce a systematic error in the BAO and RSD measurements. (2011) pointed out that the complicated radiative transfer (RT) of the resonant Lyman- α emission line generates an anisotropic selection bias in the LAE clustering on large scales, s ≳ 10 M p c. 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). Context:Lyman- α emitters (LAEs) are a promising probe of the large-scale structure at high redshift, z ≳ 2. ![]()
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