论文标题
从无线电选择样品中对宇宙星形密度的新估计，以及$ h $黑色的星系的贡献，$ z \ geq 3 $
A new estimate of the cosmic star formation density from a radio-selected sample, and the contribution of $H$-dark galaxies at $z \geq 3$
论文作者
论文摘要
宇宙的恒星形成速率密度（SFRD）历史悠久至红移$ z \ sim 2 $。在较早的宇宙时代，图片主要是从紫外线选择的星系（例如Lyman-Break Galaxies，LBGS）中推断出来的。但是，LBGS的推断SFR在很大程度上取决于假定的尘埃灭绝校正，该校正在高$ z $时并未得到很好的约束，而无线电域中的观察不受此问题的影响。在这项工作中，我们从1.4 GHz选择的$ \ sim $ 600星系中的SFRD衡量的是，到Redshift $ \ sim 3.5 $。我们考虑了红外拉迪奥相关性的主动银河核的贡献。我们测量带有修改后的Schechter函数的无线电发光函数，并得出SFRD。宇宙SFRD的上升至$ z \ sim 2 $，然后几乎平坦的高原高达$ z \ sim 3.5 $。我们的SFRD与其他FIR/无线电调查的SFRD一致，比LBG样品高2个。我们还估计，HST/WFC3 H波段（$ h $ -dark）中缺少对应物的星系组成$ \ sim 25 \％25 \％$相对于z $ \ sim 3.2 $的完整样本，相对于LBG样品，$ 58 \％$ $ 58 \％。
The Star Formation Rate Density (SFRD) history of the Universe is well constrained up to redshift $z \sim 2$. At earlier cosmic epochs, the picture has been largely inferred from UV-selected galaxies (e.g. Lyman-break galaxies, LBGs). However, LBGs' inferred SFRs strongly depend on the assumed dust extinction correction, which is not well-constrained at high-$z$, while observations in the radio domain are not affected by this issue. In this work we measure the SFRD from a 1.4 GHz-selected sample of $\sim$600 galaxies in the GOODS-N field up to redshift $\sim 3.5$. We take into account the contribution of Active Galactic Nuclei from the Infrared-Radio correlation. We measure the radio luminosity function, fitted with a modified Schechter function, and derive the SFRD. The cosmic SFRD shows a rise up to $z \sim 2$ and then an almost flat plateau up to $z \sim 3.5$. Our SFRD is in agreement with the ones from other FIR/radio surveys and a factor 2 higher than those from LBG samples. We also estimate that galaxies lacking a counterpart in the HST/WFC3 H-band ($H$-dark) make up $\sim 25\%$ of the $ϕ$-integrated SFRD relative to the full sample at z $\sim 3.2$, and up to $58\%$ relative to LBG samples.
