Oak Ridge National Laboratory

Physics Division

Physics Division Seminars

Physics Division Seminars bring us speakers on a variety of physics related subjects. Usually these are held in the Building 6008 large Conference Room, at 3:00 pm on the chosen day, but times and locations may vary. For more information, contact our seminar chairman,

Alfredo Galindo-Uribarri
Tel (Office): (865) 574-6124  (FAX): (865) 574-1268


Mon., February 16, 2004, at 11:00 a.m. (refreshments served at 10:40 a.m.)

Relativistic R-Matrix Theory and Atomic Astrophysics

Guo-Xin Chen, Ohio State University
Building 6008 Conference Room

I will review first the relativistic R-matrix (RRM) theory and detail our new work on the development of a full Breit-Pauli RRM code with the inclusion of two-body terms. Next I will present our recent RRM calculations of fundamental atomic astrophysical processes. Based upon these calculations: (I) we have developed a consistent method to constrain a set of physical conditions {electron density Ne, electron temperature Te, luminosity L*, dilution factor W(r) or radiation emitting distance r} in astrophysical plasmas; (II) we have solved two long-standing X-ray line intensity ratio problems of 3C/3D and 3s/3d in Fe XVII important for X-ray astronomy; (III) our calculations of resonant K\alpha and L-shell X-ray absorptions might possibly distinguish between different models of a dusty warm absorber and/or gravitational redshift and broadening due to AGN MCG --6-30-15 thought to harbor super-massive black holes. Finally, I will talk about our RRM code and calculations that are directly related to the nebular spectra modeling of type Ia supernovae in particular for iron peak elements Fe, Co, Ni.

Guo-Xin
chen@astronomy.ohio-state.edu

host: D. Schultz