arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1005.0388astro-ph.CO
收藏

在SZE + X射线巡天中使用星系团作为约束宇宙学的规则系综

Using clusters in SZE + x-ray surveys as an ensemble of rulers to constrain cosmology

Satej Khedekar, Subhabrata Majumdar

摘要:

正在进行和即将进行的X射线和SZE调查预计将联合检测到许多集群,因为天空覆盖范围有很大的重叠。我们发现,这些集群可以被用来作为一个合奏的标尺,以估计角直径距离,DA(Z)。这不需要额外的观测成本,因为这些集群形成了一个更大样本的子集,组装起来构建集群数量计数dn/dz。在使用该d_A(z)时,暗能量约束可以比仅使用dn/dn的约束改善1.5 - 4倍。即使在存在100个团簇的质量跟踪(用于质量校准)的情况下,暗能量约束可以进一步收紧2 - 3倍。从聚类中添加d_A(z)类似于从SNe观测中添加d_L(z);例如,dn/dn(来自ACT/SPT)加上d_A(z)在约束Omega_m和sigma_8时与dn/dz加上d_L(z)相当。

英文摘要:

Ongoing and upcoming surveys in x-rays and SZE are expected to jointly detect many clusters due to the large overlap in sky coverage. We show that, these clusters can be used as an ensemble of rulers to estimate the angular diameter distance, d_A(z). This comes at no extra observational cost, as these clusters form a subset of a much larger sample, assembled to build cluster number counts dn/dz. On using this d_A(z), the dark energy constraints can be improved by factors of 1.5 - 4, over those from just dn/dn. Even in the presence of a mass follow-up of 100 clusters (done for mass calibration), the dark energy constraints can be further tightened by factors of 2 - 3 . Adding d_A(z) from clusters is similar to adding d_L(z), from the SNe observations; for eg., dn/dn (from ACT/SPT) plus d_A(z) is comparable to dn/dz plus d_L(z) in constraining Omega_m and sigma_8.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑