Title:The molecular environments of supernova remnants

Speaker: Yang Chen (Nanjing University)

Time & Place: Thursday, 3:00pm, March 20th, Lecture Hall, 3rd floor

Abstract: Supernova remnants (SNRs) are a key form for the feedback of metal and energy to the galaxies. They are widely thought to be the accelerators of the cosmic rays below the “knee". A number of SNRs are expected and discovered to be born and evolve in a molecular gas environment, thus important for testing the cosmic ray protons. The evidences of interaction between the SNRs and molecular clouds, as have been catalogued, come from multi-wavelength studies. Recent detailed spectroscopic mapping of a series of SNRs in molecular lines reveal them to be in cavities of molecular gas, with hint of roles the progenitors have played. We predict a linear correlation of the wind bubble sizes of main-sequence OB stars with the stellar masses in a molecular environment and will discuss its implication for supernova progenitors. The molecular environment of SNRs can serve as a good probe for the gamma-rays arising from the hadronic interaction of the accelerated protons, and this talk will also present a discussion on the available gamma-ray spectra of the interacting SNRs.

Biog: Yang Chen, professor in the Department of Astronomy at Nanjing University, works in the field of physics of interstellar medium and supernova remnants. He obtained his PhD degree from Nanjing in 1993, and has spent time at the Arcetri Observatory (Italy), Harvard-Smithsonian Astrophysical Center (USA), and the University of Massachusetts (USA). He has served as an SOC member for several SNR sessions in IAU and COSPAR conferences. In 2007 he was awarded the "Distinguished Youth's Scientific Funding" by the NSFC.