090323

We propose to complete the last virgul5% of high-quality observations for the eeHIFLUGCS galaxy cluster sample (16 of 376 clusters). The sample is based on ROSAT with completely and homogeneously redetermined fluxes as well as updated redshifts. For the already observed clusters we have also identified and amp amp amp gt 10 double/triple clusters and clusters dominated by AGN emission which then fall below the flux limit of 5e-12 erg/s/cm2. With the completed follow-up observations we will decrease the uncertainties in OmegaM by a factor of 2.8 compared to those obtained with the HIFLUGCS sample. If these virgul5% do not get observed the flux-limited sample drops by almost a factor of 3 to a disappointing 140 clusters. The observations will have long lasting legacy value for a range of astrophysical studies. [truncated! Please see actual data for full text]

本研究提议完成eeHIFLUGCS星系团样本中最后约5%的高质量观测任务，该样本总计包含376个星系团，本次待观测的为其中16个。该样本基于伦琴X射线天文台（ROSAT）的数据，其通量已被完全且均匀地重新测定，红移也已完成更新。针对已完成观测的星系团，我们已识别出超过10个双/三重星系团，以及以活动星系核（AGN）辐射为主的星系团；此类星系团的通量会低于5×10⁻¹² erg·s⁻¹·cm⁻²的通量极限。相较于仅使用HIFLUGCS样本得到的结果，完成后续观测后，我们可将物质密度参数（OmegaM）的不确定度降低2.8倍。若这最后约5%的样本未被观测，通量受限样本的数量将锐减近3倍，仅剩140个星系团，这一结果令人遗憾。本次观测项目将为一系列天体物理研究提供长期的科学遗产价值。内容已截断，请查阅完整数据源以获取全文。

搜集汇总

背景与挑战

背景概述

该数据集来自欧洲空间局的XMM-Newton任务，专注于宇宙学研究，针对天空中最亮的约400个星系团（eeHIFLUGCS样本）进行观测。通过完成剩余约5%的高质量观测，旨在显著降低宇宙学参数OmegaM的不确定性，相比之前样本可减少2.8倍，同时数据具有长期的天体物理研究价值。