Speaker
Dr
Luigi Tibaldo
(PD)
Description
Cygnus X is a conspicuous massive star-forming region in the Local Spur of the Galaxy at ~1.4 kpc from the solar system. Gamma-ray observations can be used to trace cosmic rays (CRs) interacting with the ambient gas and low-energy radiation fields. Using the Fermi Large Area Telescope (LAT) we have discovered the presence of a 50-pc wide cocoon of freshly-accelerated CRs in the region bounded by the ionization fronts from the young stellar clusters. On the other hand, the LAT data show that the CR population averaged over the whole Cygnus complex on a scale of ~400 pc is similar to that found in the interstellar space near the Sun. We will discuss these results which confirm the long-standing hypothesis that massive star-forming regions host CR factories and which shed a new light on the early phases of CR life in such a turbulent environment.
Primary authors
Prof.
Isabelle Grenier
(AIM-Universite Paris 7/CEA Saclay)
Dr
Luigi Tibaldo
(PD)
