Finding bright $z\ge 6.6$ Lyman-$\alpha$ emitters with lensing: prospects for Euclid

Abstract

We model the $z\ge 6.6$ Ly$\alpha$ luminosity function to estimate the number of lensed high$-z$ Ly$\alpha$ emitters that may be detected by the Euclid Deep Survey. To span the whole range of possible predictions we exploit two Ly$\alpha$ luminosity function models and two strong gravitational lensing models from the literature. We show that the planned Euclid Deep Survey observing 40 deg${}^2$ over the 920-1850 nm wavelength range down to a flux limit of $F_{lim}=5\times 10^{-17}$erg s${}^{-1}$cm${}^{-2}$ will enable us to find between $\sim 0.85$ and $\sim 1.82$ deg${}^{-2}$ lensed Ly$\alpha$ emitters at $z\ge 6.6$ depending on the adopted Ly$\alpha$ luminosity function and strong gravitational lensing model. The obvious [OII], [OIII] and H$\beta$ contaminants of the Ly$\alpha$ lensed population will be identified with the help of Euclid's spectral resolving power, while the SKA will enable the identification of the interloper population of H$\alpha$ emitters. By combining Euclid and the SKA, we will thus be able to identify, for the first time, a sample of $\sim 34$ to $\sim 73$ lensed Ly$\alpha$ emitters at $z\ge 6.6$.

Accepted for publication in MNRAS on 20 June 2017. (NEW: Amended Latex)

References in corpus (11)

• Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report
• 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
• The Detection of a Population of Submillimeter-Bright, Strongly-Lensed Galaxies
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• Identification of the brightest Lyα emitters at z=6.6: implications for the evolution of the luminosity function in the re-ionisation era
• Accelerated Evolution of Ly$\alpha$ Luminosity Function at $\text{z}\gtrsim 7$ Revealed by the Subaru Ultra-Deep Survey for Ly$\alpha$ Emitters at $\text{z}=7.3$
• Confirmation of a Steep Luminosity Function for Lyman-alpha Emitters at z = 5.7: A Major Component of Reionization
• First Spectroscopic Confirmations of z ~ 7.0 Lya Emitting Galaxies in the LAGER Survey
• A High Space Density of Luminous Lyman Alpha Emitters at z~6.5
• Up to 100,000 reliable strong gravitational lenses in future dark energy experiments
• Dark-ages reionization and galaxy formation simulation--VII. The sizes of high-redshift galaxies

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