Ingolfur Agustsson, Tereasa G. Brainerd
We compute the locations of satellite galaxies in the Two-Degree Field Galaxy
Redshift Survey using two sets of selection criteria and three sources of
photometric data. Using the SuperCOSMOS r_F photometry, we find that the
satellites are located preferentially near the major axes of their hosts, and
the anisotropy is detected at a highly-significant level (confidence levels of
99.6% to 99.9%). The locations of satellites that have high velocities relative
to their hosts are statistically indistinguishable from the locations of
satellites that have low velocities relative to their hosts. Additionally,
satellites with passive star formation are distributed anisotropically about
their hosts (99% confidence level), while the locations of star-forming
satellites are consistent with an isotropic distribution. These two
distributions are, however, statistically indistinguishable. Therefore it is
not correct to interpret this as evidence that the locations of the
star-forming satellites are intrinsically different from those of the passive
satellites.
View original:
http://arxiv.org/abs/1110.5920
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