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| Paper: |
The cosmological evolution of BL Lacertae objects |
| Volume: |
21, The Space Distribution of Quasars |
| Page: |
218 |
| Authors: |
Stocke, John T.; Perlman, Eric S.; Wurtz, Ron; Morris, Simon L. |
| Abstract: |
Using a complete, X-ray selected sample of BL Lacertae Objects (XBLs), we find that Ve/V sub a = 0.34 +/- 0.06 implying that the cosmological evolution of this type of AGN is 'negative'; i.e., fewer or less luminous BL Lacs in the past compared to the current epoch. In the process of deriving this result, the selection criteria and observational properties of XBLs are described. |
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