XXL

• The XXL Survey is the largest survey carried out by the XMM-Newton satellite and covers a total area of 50 square degrees distributed over two fields.

• 该天区中的星系群和星系团样本中的成员星系的红移数据见 https://arxiv.org/abs/1710.04667

结论是光度函数貌似和星系团光度无关