lovely day, here at the beach
we have a busy week, the start of a busy month
we'll be doing multiple populations in depth, again,
and yet more on IMBH
this morning we contemplate, via Mario, whether globulars occupy a fundamental plane like galaxies, maybe even the same plane
log(Re) = 1.24 log(σ) + 0.33 SBe - 8.895 (for galaxies)
refs Djorgovski 1995 and Pasquato & Bertin 2008
1.24? 1.24!
Observers are soooooooo silly sometimes.
Clearly it must be 5/4 and 1/3
I mean 31/25 is just a silly number.
There is still a fundamental plane though P&B have somewhat different slope and a zero point offset
anyway, globs have:
log(Re) = 1.09 +/- log(σ) + 0.3 +/- 0.05 SBe + γ
(from P&B '08) where γ ~ -8.52 +/- 2
somewhat interestingly, the residuals for the FP correlate with the slope of the central surface brightness (cf Noyola and Gebhardt)
[man, those observers get very excitable about their correlations
that woke me up...]
can the dreaded "survival triangle" explain a plane?
Does the GC FP line up with the E FP, or do they bend?
Which one do the Ultra Compact Galaxies (tres trendy) fit on...?
for virial systems you expect log(Re) = 2 log(σ) + 0.4 SBe + γ
marginally consistent
but globulars are relaxed, [I suspect the problem is with the "e"...]
oh, dear, we really don't know the asymptotic surface density profile slope at large radii,
how embarrassing; too noisy and too much uncertainty in background subtraction
globulars are just too big on the sky...
more data is needed - need a homogenous multi-colour wide field CCD data set of all the globulars...
'course doing this with CCDs is a pain in ass - too much data
hm, a graduate student is needed.
may get done incidental to other sky survey projects, eventually, if anyone actually reduces the data when it gets there
we need a 10m wide field NIR/Optical space telescope.
stat.