New surface photometry of all known elliptical galaxies in the Virgo cluster
is added to published data to derive composite profiles over large dynamic
ranges. Sersic functions fit them remarkably well. Effective brightnesses and
radii are derived via Sersic fits and by integrating the profiles
nonparametrically. We strongly confirm two dichotomies: (1) Elliptical galaxies
from cDs to M32 form a tight sequence in Fundamental Plane parameter space that
is almost perpendicular to the sequence of spheroidal galaxies from NGC 205 to
Draco. This is consistent with our understanding of their different formation
processes: mergers for Es and conversion of late-type galaxies into spheroidals
by environmental effects and by energy feedback from supernovae. (2)
Ellipticals come in two varieties: e.g., our 10 brightest Es have cuspy cores;
our 17 fainter Es do not have cores. We find a new distinct component in
coreless Es. All have extra light at the center above the inward extrapolation
of the outer Sersic profile. We suggest that extra light is made by starbursts
in dissipational (wet) mergers, as in numerical simulations. Three other new
aspects also point to an explanation of how the E-E dichotomy formed: extra
light Es were made in wet mergers while core Es were made in dry mergers. We
confirm that core Es do and extra light Es generally do not contain X-ray gas.
This suggests why the E-E dichotomy arose. Only core Es and their progenitors
are massive enough to retain hot gas that can make dry mergers dry and protect
old star populations from late star formation.Comment: 94 pages, 77 figures from 170 Postscript files; requires
emulateapj.sty, apjfonts.sty, and psfig.sty; accepted for publication in
ApJS; for a version with full resolution figures, see
http://chandra.as.utexas.edu/~kormendy/kfcb.htm