论文标题
CIV吸收器的进化I.宇宙发病率
Evolution of CIV Absorbers I. The Cosmic Incidence
论文作者
论文摘要
我们对CIV吸收器的分布和演变进行了一项大型的高分辨率研究,其中包括最弱的宽度$ W_R <0.3 $ 〜BOW。 By searching 369 high-resolution, high signal-to-noise spectra of quasars at $1.1\leq z_{em} \leq5.3$ from Keck/HIRES and VLT/UVES, we find $1268$ CIV absorbers with $W_r \geq 0.05$~Å (our $\sim50\%$ completeness limit) at redshifts $1\leq z \ leq4.75 $。 Schechter函数描述了观察到的等效宽度分布,从幂律向指数下降到$ w_r \ gtrsim 0.5 $ 〜〜。 Power-Law Slope $α$从$ \ sim7 \%$上升,并从$ \ langle z \ rangle = 1.7 $ to $ \ langle = 1.7 $ to $ \ langle z \ langle z \ langle z \ rangle = 3.6 $。我们发现,$ w_r \ geq 0.05 $〜的共同移动红移路径密度($ dn/dx $)从$ z \ simeq 4.0 $升至$ z \ z \ simeq 1.3 $,而$ w_r w_r \ geq 0.6 $ $ $ $ $ $ $ $ dn $ d a aim y a y/d dx af simeq 1.3 $ a $ \ sim1.8 $ times。我们通过一个模型来量化观察到的演变,其中$ dn/dx $随着红移线性降低。该模型表明,具有较大$ W_R $阈值的种群随红移而更快地发展,后来出现在宇宙中。 $ z = 3-5 $的宇宙学技术彩色模拟过度生产了$ W_R <0.3 $ 〜〜 $ 〜0.3 $ 〜〜的吸收商的丰富度,同时在较高的$ W_R $中产生更好的协议。我们的经验线性模型成功地描述了{civ在模拟中的进化和过去的$ w_r \ geq 0.6 $ 〜〜CIV的演变,过去$ \ sim12 $ gyr。将我们的测量与文献相结合,使我们的图像在最后的$ \ \ \ \ y \ y \ y \ sim6 $ to $ z \ sim0 $的最后$ \ of 13 $ gyr中变得越来越多,而且/或更大的物理大小。
We present a large high-resolution study of the distribution and evolution of CIV absorbers, including the weakest population with equivalent widths $W_r<0.3$~Å. By searching 369 high-resolution, high signal-to-noise spectra of quasars at $1.1\leq z_{em} \leq5.3$ from Keck/HIRES and VLT/UVES, we find $1268$ CIV absorbers with $W_r \geq 0.05$~Å (our $\sim50\%$ completeness limit) at redshifts $1\leq z \leq4.75$. A Schechter function describes the observed equivalent width distribution with a transition from power-law to exponential decline at $W_r \gtrsim 0.5$~Å. The power-law slope $α$ rises by $\sim7\%$ and transition equivalent width $W_{\star}$ falls by $\sim\!20\%$ from $\langle z \rangle=1.7$ to $\langle z \rangle=3.6$. We find that the co-moving redshift path density, $dN/dX$, of $W_r \geq 0.05$~Å absorbers rises by $\sim1.8$ times from $z\simeq 4.0$ to $z\simeq 1.3$, while the $W_r \geq 0.6$~Å $dN/dX$ rises by a factor of $\sim8.5$. We quantify the observed evolution by a model in which $dN/dX$ decreases linearly with redshift. The model suggests that populations with larger $W_r$ thresholds evolve faster with redshift and appear later in the universe. The cosmological Technicolor Dawn simulations at $z=3-5$ over-produce the observed abundance of absorbers with $W_r<0.3$~Å, while yielding better agreement at higher $W_r$. Our empirical linear model successfully describes {CIV evolution in the simulations and the observed evolution of $W_r \geq 0.6$~Å CIV for the past $\sim12$ Gyr. Combining our measurements with the literature gives us a picture of CIV-absorbing structures becoming more numerous and/or larger in physical size over the last $\approx13$ Gyr of cosmic time ($z\sim6$ to $z\sim0$).