The evolution of the UV luminosity and stellar mass functions of Lyman-alpha emitters from z~2 to z~6

Abstract

We measure the evolution of the rest-frame UV luminosity function (LF) and the stellar mass function (SMF) of Lyman-alpha (Lya) emitters (LAEs) from z~2 to z~6 by exploring ~4000 LAEs from the SC4K sample. We find a correlation between Lya luminosity (LLya) and rest-frame UV (M_UV), with best-fit M_UV=-1.6+-0.2 log10(LLya/erg/s)+47+-12 and a shallower relation between LLya and stellar mass (Mstar), with best-fit log10( Mstar/Msun)=0.9+-0.1 log10(LLya/erg/s)-28+-4.0. An increasing LLya cut predominantly lowers the number density of faint M_UV and low Mstar LAEs. We estimate a proxy for the full UV LFs and SMFs of LAEs with simple assumptions of the faint end slope. For the UV LF, we find a brightening of the characteristic UV luminosity (M_UV*) with increasing redshift and a decrease of the characteristic number density (Phi*). For the SMF, we measure a characteristic stellar mass (Mstar*/Msun) increase with increasing redshift, and a Phi* decline. However, if we apply a uniform luminosity cut of log10 (LLya/erg/s) >= 43.0, we find much milder to no evolution in the UV and SMF of LAEs. The UV luminosity density (rho_UV) of the full sample of LAEs shows moderate evolution and the stellar mass density (rho_M) decreases, with both being always lower than the total rho_UV and rho_M of more typical galaxies but slowly approaching them with increasing redshift. Overall, our results indicate that both rho_UV and rho_M of LAEs slowly approach the measurements of continuum-selected galaxies at z>6, which suggests a key role of LAEs in the epoch of reionisation.

Accepted for publication in MNRAS. 20 pages, 13 figures, 4 tables

References in corpus (29)

• The Cosmic Evolution Survey (COSMOS) -- Overview
• A simple model to interpret the ultraviolet, optical and infrared emission from galaxies
• UV Luminosity Functions at redshifts z~4 to z~10: 10000 Galaxies from HST Legacy Fields
• The Herschel view of the dominant mode of galaxy growth from z=4 to the present day
• UltraVISTA: a new ultra-deep near-infrared survey in COSMOS
• The Subaru/XMM-Newton Deep Survey (SXDS). IV. Evolution of Lya Emitters from z=3.1 to 5.7 in the 1 deg^2 Field: Luminosity Functions and AGN
• An ALMA survey of Sub-millimeter Galaxies in the Extended Chandra Deep Field South: Physical properties derived from ultraviolet-to-radio modelling
• Distant Radio Galaxies and their Environments
• The mass evolution of the first galaxies: stellar mass functions and star formation rates at $4<z<7$ in the CANDELS GOODS-South field
• The galaxy stellar mass function at 3.5<z<7.5 in the CANDELS/UDS, GOODS-South, and HUDF fields
• A Population of Faint Extended Line Emitters and the Host Galaxies of Optically Thick QSO Absorption Systems
• Star Formation at $4<z<6$ From the Spitzer Large Area Survey with Hyper-Suprime-Cam (SPLASH)
• Identification of the brightest Lyα emitters at z=6.6: implications for the evolution of the luminosity function in the re-ionisation era
• Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4
• The VIMOS Ultra-Deep Survey (VUDS): fast increase of the fraction of strong Lyman alpha emitters from z=2 to z=6
• Deconstructing the Galaxy Stellar Mass Function with UKIDSS and CANDELS: the Impact of Colour, Structure and Environment
• Deficiency of large equivalent width Lyman-alpha emission in luminous Lyman break galaxies at z~5-6?
• The MUSE Hubble Ultra Deep Field Survey VI: The Faint-End of the Lya Luminosity Function at 2.91 < z < 6.64 and Implications for Reionisation
• A VLT/FORS2 view at $z\sim 6$: Lyman-$\alpha$ emitter fraction and galaxy physical properties at the edge of the epoch of cosmic reionization
• Spectroscopic properties of luminous Lyman-α emitters at $z\approx 6-7$ and comparison to the Lyman-break population
• The MUSE Hubble Ultra Deep Field Survey X. Ly$\alpha$ Equivalent Widths at $2.9<z<6.6$
• Physical properties of z~4 LBGs: differences between galaxies with and without Ly-alpha emission
• A Comprehensive Study of Ly$\alpha$ Emission in the High-redshift Galaxy Population
• The evolution of rest-frame UV properties, Lya EWs and the SFR-Stellar mass relation at z~2-6 for SC4K LAEs
• UVUDF: UV Luminosity Functions at the cosmic high-noon
• The MUSE-Wide survey: A measurement of the Ly$\alpha$ emitting fraction among $z>3$ galaxies
• The Stellar Mass, Star Formation Rate and Dark Matter Halo Properties of LAEs at $z\sim 2$
• The Ultraluminous Lyman Alpha Luminosity Function at z=6.6
• Differences and similarities of stellar populations in LAEs and LBGs at $z\sim$ 3.4 - 6.8

Cited by in corpus (8)

• (Re)Solving Reionization with Lyα: How Bright Lyα Emitters account for the $z\approx 2-8$ Cosmic Ionizing Background
• GALLUMI: A Galaxy Luminosity Function Pipeline for Cosmology and Astrophysics
• The space density of ultra-luminous QSOs at the end of reionization epoch by the QUBRICS Survey and the AGN contribution to the hydrogen ionizing background
• The HETDEX Survey: Emission Line Exploration and Source Classification
• Photometric IGM Tomography: Efficiently Mapping Quasar Light Echoes with Deep Narrow Band Imaging
• The miniJPAS & J-NEP surveys: Identification and characterization of the Ly$\alpha$ Emitter population and the Ly$\alpha$ Luminosity Function
• The PAU Survey: The quasar UV and Ly$\alpha$ luminosity functions at $2.7<z<5.3$
• Far-infrared observations of dust in Ly$\alpha$ emitters at z=2-6