Two Lensed Lyman-alpha Emitting Galaxies at z~5

Abstract

We present observations of two strongly lensed $z\sim 5$ Lyman-$\alpha$ Emitting (LAE) galaxies that were discovered in the Sloan Giant Arcs Survey (SGAS). We identify the two sources as SGAS J091541+382655, at $z=5.200$, and SGAS J134331+415455 at $z=4.994$. We measure their AB magnitudes at $(i,z)=(23.34\pm 0.09,23.29\pm 0.13$) mags and $(i,z)=(23.78\pm 0.18,24.24_{-0.16}^{+0.18}$) mags, and the rest-frame equivalent widths of the Lyman-$\alpha$ emission at $25.3\pm 4.1$Å~and $135.6\pm 20.3$Å~for SGAS J091541+382655 and SGAS J134331+415455, respectively. Each source is strongly lensed by a massive galaxy cluster in the foreground, and the magnifications due to gravitational lensing are recovered from strong lens modeling of the foreground lensing potentials. We use the magnification to calculate the intrinsic, unlensed Lyman-$\alpha$ and UV continuum luminosities for both sources, as well as the implied star formation rates (SFR). We find SGAS J091541+382655 and SGAS J134341+415455 to be galaxies with (L${}_{Ly-\alpha }$, L${}_{UV})\le (0.6$L${}_{Ly-\alpha }^{\ast },2$L${}_{UV}^{\ast }$) and (L${}_{Ly-\alpha }$, L${}_{UV})=(0.5$L${}_{Ly-\alpha }^{\ast },0.9$L${}_{UV}^{\ast }$), respectively. Comparison of the spectral energy distributions (SEDs) of both sources against stellar population models produces estimates of the mass in young stars in each galaxy: we report an upper limit of M${}_{stars}\le 7.9_{-2.5}^{+3.7}\times 10^7$ M$_{\sun} h_{0.7}^{-1}$ for SGAS J091531+382655, and a range of viable masses for SGAS J134331+415455 of $2\times 10^8$ M$_{\sun} h_{0.7}^{-1} <$ M${}_{stars}<6\times 10^9$ M$_{\sun} h_{0.7}^{-1}$.

10 pages, 8 figures, emulate apj format, Accepted to ApJ

References in corpus (15)

• A Bayesian approach to strong lensing modelling of galaxy clusters
• UV Luminosity Functions at z~4, 5, and 6 from the HUDF and other Deep HST ACS Fields: Evolution and Star Formation History
• 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
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• The luminosity function, halo masses and stellar masses of luminous Lyman-break galaxies at redshifts 5<z<6
• A Luminosity Function of Lyman Alpha Emitting Galaxies at Redshift 4.5
• A New Survey for Giant Arcs
• Effects of Dust Geometry in Lyman Alpha Galaxies at z = 4.4
• Lyman Alpha Emitters at Redshift 5.7 in the COSMOS Field
• A very bright, highly magnified Lyman-break galaxy at z=3.07
• Lyman alpha emission in high-redshift galaxies
• Turning Back the Clock: Inferring the History of the Eight O'clock Arc
• A z=0.9 supercluster of X-ray luminous, optically-selected, massive galaxy clusters
• The DEEP2 Redshift Survey: Lyman Alpha Emitters in the Spectroscopic Database
• Discovery of four gravitational lensing systems by clusters in the SDSS DR6

Cited by in corpus (1)

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