|
Seminar Title |
Pinning down the origin of Galactic cosmic rays by using gamma-ray observations |
| |
|
| Speaker: |
Dr. TIAN Feng |
| |
|
|
Affiliation: |
(The Max Planck institute of nuclear physics ) |
| |
|
| When |
Thurseday morning , Apr. 18, 10:00 a.m |
| |
|
|
Where: |
Room 502, Astronomy Building. (NJU) |
| |
Welcome to Attend |
| |
| |
( PMO Academic Committee & Academic Circulating committee) |
| |
Abstract: The origin of Cosmic rays (CRs) still remains as a mystery. The diffusion of CRs in turbulent magnetic fields erases the information on the distribution of CR accelerators. The energy dependent diffusion of CRs also significantly modifies the initial (acceleration) spectra of CRs. As a result, gamma-rays, the secondaries from CR interaction with ambient gas, tell us more information about the origin of CRs. This can be done in two ways:
1. the gamma-ray emissions, especially those associated with ambient gas, can be used to study the distribution of CR throughout the Galaxy. In this regard I will discuss the latest results of CR radial distribution by analysing the Fermi LAT as well as CO/HI/Infrared data.
2. the discrete gamma-ray sources can elucidate the locations of individual CR accelerators. Here I will report the recent detection of extended young star cluster NGC 3603 and Westerlund 2.
