Title:　　　　　Constraints on early expansion in Type Ib/c SNe with VLBI

Speaker:　　　 Dr. Zsolt Paragi　　　　　　　　　　　　　 

Affiliation:　　  Joint Institute for VLBI in Europe (JIVE)

Time:　　　　 10am, (Tuesday) April 26, 2011

Location:　　 Middle Conference Room, 3rd floor


Abstract:　
Gamma-ray bursts (GRB) are sometimes related to Type Ib/c supernovae. The former produce massive outbursts initially in the gamma-rays originating in highly collimated relativistic ejecta pointing in our line of sight, while the latter are the result of the core-collapse of very massive stars, and they realease most of their energy in the optical regime. It has been suggested that a fraction of Type Ib/c SNe may produce (mildly-)relativistic jets which we see at a larger viewing angle. We carried out radio Very Long Baseline Interferometry (VLBI)observations of Type Ib/c SNe in an attempt to constrain their expansion velocities at early times.