Tel Aviv University

Tel Aviv University
Physics Colloquium

Academic Year  2011 - 2012

The colloquium is held at Melamed Hall (Room 6) in the Shenkar Physics Building, every Sunday at 16:10. Light refreshments are served outside Melamed Hall at 15:50. 


December 18, 2011

The 2012 John Bahcall Lecture in Astrophysics
"The Formation of Massive Stars"

Prof. Christopher F. McKee
Departments of Astronomy and of Physics, University of California, Berkeley

  John Bahcall was one of the greatest astrophysicists of the last 50 years. His impact extended well beyond his research, through his mentoring of generations of astrophysicists and his influence on science policy. His work touched many fields, including the study of supernovae, most of which result from the explosion of stars with a mass more than about 10 times the mass of the Sun. Such stars are responsible for creating most of the heavy elements in the universe, for governing the evolution of galaxies, and quite possibly for re-ionizing the universe a few hundred million years after the Big Bang. The formation of these stars can be understood as an extension of the theory of low-mass star formation, generalized to include the effects of interstellar turbulence. However, a major problem must be overcome: For massive stars, the outward force due to radiation pressure exceeds the inward force due to gravity; how can gas accrete onto the protostar in that case? Circumstellar disks, outflow cavities, and radiative Rayleigh-Taylor instabilities all contribute to the solution of this problem. These conclusions are validated by means of 3D radiation-hydrodynamic simulations of high-mass star formation. Massive stars are powerful sources of ionizing radiation, which has a significant impact on star formation.  

Host: Prof. Amiel Sternberg, x7590
Fall 2011 Schedule

For more information or for directions to Melamed Hall please contact:
Chava Balson  03-6408636

To suggest potential speakers or register feedback contact: Ron Lifshitz  03-6405145.

Sponsored by:   The Raymond and Beverly Sackler School of Physics & Astronomy, The Faculty of Exact Sciences, Tel Aviv University.