1. Intimate Life in the Galactic Center
ASCI/Alliances Center for Astrophysical Thermonuclear Flashes
Sgr A* and Sgr A East
Intimate Life in the Galactic Center
Tomasz Plewa ASCI Flash Center, University of Chicago
Michal Rozyczka Copernicus Astronomical Center, Warsaw
December 3, 2001
in 2.5D
December 3, 2001

2. Galactic Center Trivia
distance ~8 kpc
extinction several 10s in V
linear size of Sgr A*: mas (6.2x1013 cm)
December 3, 2001

3. GC on 100s pc scale
December 3, 2001

4. Gaseous component
December 3, 2001

5. X-ray emission of molecular gas
no powerful ionizing sources
December 3, 2001

6. Young helium stars
December 3, 2001

7. Central object
December 3, 2001

8. Accretion from * winds
December 3, 2001

9. Sgr A*/Sgr A East
December 3, 2001

10. Model characteristics
Uniform medium
Optically thin cooling, 3 times solar metallicity
Gravitational equilibrium for the ambient gas
Static gravitational potential, m=2.6x106 solar
Cylindrical 2.5D geometry
Adaptive mesh refinement, ~ zones,
2.5 mas, 10-4 pc, 2.8x1014 cm, 300 Rg
December 3, 2001

11. One-dimensional models
December 3, 2001

12. Two-dimensional models
December 3, 2001

13. Luminosity and accretion rates
December 3, 2001

14. Conclusions
vicinity of the central region appears to be dominated by Sgr A East; uncertain role of stellar winds
size constraint favors low-density background with interaction beginning ~ years after SN explosion
violent interaction approaching a quasi-steady with a stream-like accretion
rapid rise in luminosity; high-luminosity state lasting for several hundred years
thermal emission peaking in hard X-rays with total luminosity in the range of ergs range depending on the background density
December 3, 2001