The Subaru Seminar is
usually held in Room 104 of the Hilo Base Facility, adjacent
to the main lobby. Everyone is welcome to attend. If you are
interested in giving a seminar, please contact Masayuki
Akiyama by email.
Tuesday 17 June at 13:30pm
"Color Gradients in Elliptical Galaxies: Evidence for Environmental Dependence of Galaxy Formation Process ?"
Naoyuki Tamura (University of Durham, UK)
Nearby elliptical galaxies are known to have radial gradients of color
and metal absorption line strength; colors gradually become redder and
metal absorption lines become stronger towards the center, suggesting
that stellar population in an elliptical galaxy changes with radius.
Such a spatial variation of stellar population is likely to reflect
how the galaxy assembled. On the other hand, formation history of
elliptical galaxy is likely to depend on its environment. Therefore,
it is important to study the observational properties in various
environments and compare one population with another.
Radial gradients of color and metal absorption line strength gradient
have been investigated so far in several tens of nearby elliptical
galaxies. One of the shortcomings of these studies, however, is that
almost all the galaxies reside not in rich clusters but in relatively
sparse environments. Recently, we performed B and R band surface
photometry for E/S0 galaxies in rich clusters (ABELL 2199 and Coma).
Based on the results from our data and those from the literature, I
will discuss formation process of elliptical galaxy and its
Seminars are also held at JAC,