Julio Navarro (UVic) showed us that when small galaxies merge with large, if the large is oblate, the small's orbit is pulled into the "disk plane" of the oblateness by anisotropic dynamical friction. This opens up the possibility that there is structure and accretion history encoded in the disk, especially since the radius at which stuff settles is generally related to the central density of the incoming satellite. Note the contradiction—or at least tension—with the discussion last week.
I may be to optimist about signatures (I work with compact groups :-)) ), but the idea that the information can be encoded in the disk, at least for some time, seems logical.
ReplyDeleteI continued the discussion about the diffuse light below your comment
David,
ReplyDeletesome more comments on the diffuse light topic, on my link above!
:-)