tag:blogger.com,1999:blog-3612697638678594412.post3915442064887692329..comments2024-03-26T21:35:39.266-07:00Comments on CANDELS: Galaxy Masses and the "Parking Lot" ProblemAnonymoushttp://www.blogger.com/profile/17704873086455232100noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-3612697638678594412.post-65835343370319751912012-06-12T09:55:06.302-07:002012-06-12T09:55:06.302-07:00I agree that there are problems at the high mass e...I agree that there are problems at the high mass end as well. Most of the discussion at the meeting focused on "quenching" of star formation at the high mass end and whether it was internally triggered (e.g. if a galaxy gets above a certain mass) or externally triggered. Of course the quenching process might be different for galaxies that are at the centers of their dark-matter halos than ones that are satellites within a larger halo (e.g. a group or cluster of galaxies). <br /><br />And I completely agree that the observations can be inaccurate. It's great to compare models to "stellar mass functions," but also important to compare directly to the observed distribution of luminosities and colors, where it's much easier to understand the observational errors.Harry Fergusonhttps://www.blogger.com/profile/02737594514049700386noreply@blogger.comtag:blogger.com,1999:blog-3612697638678594412.post-59664588810957970342012-06-08T20:43:23.890-07:002012-06-08T20:43:23.890-07:00A really interesting post, and it sounds like a gr...A really interesting post, and it sounds like a great meeting!<br /><br />Is the problem perhaps not even more complex though? The observations seem to suggest the high mass end of the stellar mass function is in place by redshift 1. So would you not need a mechanism to increase the star formation efficiency in high mass galaxies (relative to their low mass counterparts) at early times in particular? However, this mechanism must become less effective at late times. If it didn't, the high mass end of the stellar mass function would continue to evolve and we would over-predict the abundance of the most massive galaxies. So the mechanism evoked must require a time and mass dependent evolution to it.<br /><br />Alternatively the observations could be always be inaccurate. The steepness of the stellar mass function at the high mass end makes this the regime which is most susceptible to systematics in the stellar mass determinations. Then there is always the possibility of a varying initial mass function complicating things...Simon Mutchhttps://www.blogger.com/profile/15817925058049188446noreply@blogger.com