The clustering of typical Ly α emitters from z ∼ 2.5–6: host halo masses depend on Ly α and UV luminosities

Abstract

We investigate the clustering and halo properties of ∼ 5000 Lyα-selected emission line galaxies (LAEs) from the Slicing COSMOS 4K (SC4K) and from archival NB497 imaging of SA22 split in 15 discrete redshift slices between z ∼ 2.5 − 6. We measure clustering lengths of r 0 ∼ 3 − 6 h −1 Mpc and typical halo masses of ∼ 10 11 M for our narrowband-selected LAEs with typical L Lyα ∼ 10 42−43 erg s −1 . The intermediate band-selected LAEs are observed to have r 0 ∼ 3.5 − 15 h −1 Mpc with typical halo masses of ∼ 10 11−12 M and typical L Lyα ∼ 10 43−43.6 erg s −1 . We find a strong, redshift-independent correlation between halo mass and Lyα luminosity normalized by the characteristic Lyα luminosity, L (z). The faintest LAEs (L ∼ 0.1 L (z)) typically identified by deep narrowband surveys are found in 10 10 M halos and the brightest LAEs (L ∼ 7 L (z)) are found in ∼ 5 × 10 12 M halos. A dependency on the rest-frame 1500Å UV luminosity, M UV , is also observed where the halo masses increase from 10 11 M to 10 13 M for M UV ∼ −19 mag to −23.5 mag. Halo mass is also observed to increase from 10 9.8 M to 10 12.3 M for dust-corrected UV star formation rates from ∼ 0.6 M yr −1 to 10 M yr −1 and continues to increase up to 10 13.5 M in halo mass, where the majority of those sources are AGN. All the trends we observe are found to be redshift-independent. Our results reveal that LAEs are the likely progenitors of a wide range of galaxies depending on their luminosity, from dwarf-like, to Milky Way-type, to bright cluster galaxies. LAEs therefore provide unique insight into the early formation and evolution of the galaxies we observe in the local Universe.

Web of the giant: Spectroscopic confirmation of a large-scale structure around the z = 6.31 quasar SDSS J1030+0524

“…Assuming that the auto-correlation functions of QSOs and galaxies are both power-laws with the same slope, the relation r 0,QG = (r 0,QQ × r 0,GG ) 1/2 holds, where r 0,QQ and r 0,GG are the auto-correlation lengths of QSOs and galaxies, respectively. As r 0,GG ≈ 20−30 cMpc for galaxies at z ∼ 6 with M UV and a star formation rate (SFR) similar to ours (Khostovan et al 2019), we estimate that r 0,QQ is at least ∼20 cMpc. Such a large correlation length at z ∼ 6 in turn suggests that J1030 is hosted by a dark matter halo with a mass, M h > 10 12 M (Harikane et al 2018;Khostovan et al 2019).…”

“…As r 0,GG ≈ 20−30 cMpc for galaxies at z ∼ 6 with M UV and a star formation rate (SFR) similar to ours (Khostovan et al 2019), we estimate that r 0,QQ is at least ∼20 cMpc. Such a large correlation length at z ∼ 6 in turn suggests that J1030 is hosted by a dark matter halo with a mass, M h > 10 12 M (Harikane et al 2018;Khostovan et al 2019).…”

The X-ray and radio activity of typical and luminous Ly α emitters from z ∼ 2 to z ∼ 6: evidence for a diverse, evolving population

“…Meurs & Wilson 1984). (2007) and Yamada et al (2012) found bright LAEs around dense regions of the Universe for 2 < z < 5.2 (see also Overzier 2016;Kubo et al 2013). Furthermore, more recently, Khostovan et al (2019) conducted a detailed clustering analysis of faint to luminous LAEs, including the SC4K LAEs, to find that luminous LAEs reside in the most massive dark matter haloes at high redshift, and are therefore consistent with being progenitors of some of the most massive clusters found today (see also Matsuda et al 2004).…”

“…We refer to Sobral et al (2018a) for the full selection criteria and further details regarding the SC4K LAEs. Further information regarding the rest-frame UV morphologies and sizes of SC4K LAEs can be found in Paulino-Afonso et al (2018) and Shibuya et al (2019), while the clustering properties of LAEs and their dependencies on Lyα and SFRs have been extensively studied by Khostovan et al (2019). Figure 1 shows the on-sky distribution of SC4K LAEs in the COSMOS field.…”

J-PLUS: Unveiling the brightest end of the Lyαluminosity function at 2.0 <z< 3.3 over 1000 deg2

“…The spectral properties of LAEs are usually interpreted as to be coming from young ( 50 Myr) and low-mass (M * < 10 10 M ) galaxies (e.g., Wilkins et al 2011;Amorín et al 2017;Hao et al 2018;Santos et al 2020) with small rest-frame UV half-light radii ( R 1 − 2 Kpc, as in e.g., Møller & Warren 1998;Lai et al 2008;Bond et al 2012;Guaita et al 2015;Kobayashi et al 2016;Ribeiro et al 2016;Bouwens et al 2017a;Paulino-Afonso et al 2018) which are actively star-forming (SFR ∼ 1 − 100 M /yr) and dust-poor (dust attenuation A V < 0.2, see e.g., Gawiser et al 2006Gawiser et al , 2007Guaita et al 2011;Nilsson et al 2011;Bouwens et al 2017b;Arrabal Haro et al 2020). When observed at high redshift, isolated and grouped LAEs would represent the progenitors of present-day galaxies and clusters, respectively, hence providing extremely valuable insights about structure formation (e.g., Matsuda et al 2004Matsuda et al , 2005Venemans et al 2005;Gawiser et al 2007;Overzier et al 2008;Guaita et al 2010;Mei et al 2015;Bouwens et al 2017b; Khostovan et al 2019). A basic statistical tool to study the population of high-z LAEs is the description of their number density, at a given redshift, as a function of line luminosity (L Lyα ), namely the Lyα luminosity function (LF, see e.g., Gronke et al The measured transmission curves for the J-PLUS filter set, after accounting for sky absorption, CCD quantum efficiency and the total effect of the JAST/T80 telescope optical system.…”