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arXiv · 1808.02704

A Deep Ly$\alpha$ Survey in ECDF-S and COSMOS: I. General Properties of Lyman-alpha Emitters at $z\sim2$

Cai-Na Hao·Jia-Sheng Huang·Xiaoyang Xia·Xianzhong Zheng·Chunyan Jiang·Cheng Li
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Abstract

Ly$\alpha$ Emitters (LAEs) may represent an important galaxy population in the low mass regime. We present our deep narrowband imaging surveys in the COSMOS and ECDF-S fields and study the properties of LAEs at $z=2.23\pm0.03$. The narrowband surveys conducted at Magellan II telescope allow us to obtain a sample of 452 LAEs reaching a $5\sigma$ limiting magnitude of $\sim26$ mag. Our Ly$\alpha$ luminosity functions extend to $10^{41.8}$ erg s$^{-1}$ with steep faint-end slope. Using multi-wavelength ancillary data, especially the deep Spitzer/IRAC 3.6$\mu$m and 4.5$\mu$m photometric data, we obtained reliable stellar mass estimates for 130 IRAC-detected LAEs, spanning a range of $8 < {\rm log}(M_\star/M_\odot)< 11.5$. For the remaining IRAC-undetected LAEs, the median-stacked spectral energy distribution yields a stellar mass of ${\rm log}(M_\star/M_\odot)=7.97^{+0.05}_{-0.07}$ and the rest-frame ultraviolet emission indicates a median star formation rate of ${\rm log} (SFR/M_\odot$ yr$^{-1})=-0.14\pm0.35$. There are six LAEs detected by the Spitzer/MIPS 24$\mu$m or even Herschel far-infrared observations. Taking into account the six MIR/FIR detected LAEs, our LAEs cover a wide range in the star formation rate (${\rm 1 =10.8^{+0.56}_{-1.1}}$, suggesting that they are progenitors of local Large Magellanic Cloud-like galaxies.

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Cai-Na Hao, Jia-Sheng Huang, Xiaoyang Xia, Xianzhong Zheng, Chunyan Jiang, Cheng Li. 2018-08-08. A Deep Ly$\alpha$ Survey in ECDF-S and COSMOS: I. General Properties of Lyman-alpha Emitters at $z\sim2$. https://doi.org/10.3847/1538-4357/aad80b

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