12–23 Jul 2021
Online
Europe/Berlin timezone

Probing the hadronic nature of the gamma-ray emission associated with Westerlund 2

15 Jul 2021, 18:00
1h 30m
04

04

Talk GAD | Gamma Ray Direct Discussion

Speaker

Emma Maria de Ona Wilhelmi (Z_GA (Gammaastronomie))

Description

Star-forming regions have been proposed as potential Galactic cosmic ray accelerators for decades. Cosmic ray acceleration can be probed through observations of gamma-rays produced in inelastic proton-proton collisions, at GeV and TeV energies. We analyze more than 11 years of Fermi-LAT data from the direction of Westerlund 2, one of the most massive and best-studied star-forming regions in our Galaxy. The spectral and morphology characteristics of the LAT source agree with the ones in the TeV regime (HESS J1023-575), allowing the description of the gamma-ray source from a few hundreds of MeV to a few tens of TeVs. We will present the results and discuss the implications of the identification with the stellar cluster and radiation mechanism involved.

Keywords

Stellar Clusters; Fermi LAT; Westerlund 2; Cosmic rays; gamma-rays

Subcategory Experimental Results

Primary authors

Prof. Diego Torres (Institute of Space Sciences (ICE, CSIC), Barcelona, Spain.) Emma Maria de Ona Wilhelmi (Z_GA (Gammaastronomie)) Enrique Mestre Felix Aharonian (DIAS) Pablo Miguel Saz Parkinson Roberta Zanin (0) Ruizhi Yang (Max-Planck-Institut für Kernphysik) Tim Holch (DESY) Ullrich Schwanke (Humboldt University Berlin)

Presentation materials