The Mass Density of MgII Absorbers from the Australian Dark Energy Survey
arxiv(2024)
摘要
We present an all-southern sky survey for MgII doublet absorbers in 951 z < 4
AGN/quasar spectra from the Australian Dark Energy Survey (OzDES). The spectral
resolution ranges from R = 1400-1700 over the wavelengths 3700 A-8800 A. The
survey has a 5sigma detection completeness of 50
equivalent widths W_r(2796) >= 0.3 A. We studied 656 MgII absorption systems
over the redshift range 0.33 < z < 2.19 with equivalent widths 0.3 < W_r(2796)
< 3.45 A. The equivalent width distribution is well fit by an exponential
function with W* = 0.76 +/- 0.04 A and the redshift path density exhibits very
little evolution. Overall, our findings are consistent with the large,
predominantly northern-sky, surveys of MgII absorbers. We developed and
implemented a Monte Carlo model informed by a high-resolution MgII survey for
determining the MgII mass density, Omega_MgII. We found Omega_MgII 5 x 10^-7
with no evidence of evolution over a 7 Gyr time span following Cosmic Noon.
Incorporating measurements covering 2.0 < z < 6.4 from the literature, we
extended our insights into MgII mass density evolution from the end of
reionization well past the Cosmic Noon epoch. The presented Monte Carlo model
has potential for advancing our knowledge of the evolution of mass densities of
metal-ions common to quasar absorption line studies, as it exploits the
efficiency of large low-resolution surveys while requiring only small samples
from expensive high-resolution surveys.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要