Speaker
Dr
Philippe Gros
(LLR, Ecole Polytechnique)
Description
Gamma-ray astronomy allows us to explore the non-thermal emissions of
objects such as Active Galatic Nuclei (AGN), Gamma Ray Bursts (GRB) and pulsars. Current gamma-ray telescopes based on photon conversion to electron-positron pair use tungsten converters. They suffer of limited angular resolution at low energies, and their sensitivity drops below 1 GeV. A gaseous detector can achieve higher angular resolution in the MeV-GeV range thanks to reduced multiple scattering. This gives access to the linear polarisation of the photons through the azimuthal angle of the electron-positron pair.
The HARPO Time Projection Chamber (TPC) has been designed as a
high angular resolution telescope for gamma-ray polarimetry. It was set up in a polarised gamma-ray beam at the NewSUBARU accelerator in Japan in November 2014. Data were taken at different photon energies from 1.7 MeV to 74 MeV, and with different polarisation configurations. The full experimental setup of the TPC and the photon beam will be described. The first results from the beam campaign will be shown.
Collaboration
HARPO collaboration:
D. Bernard, P. Bruel, M. Frotin, Y. Geerebaert, P. Gros, B. Giebels,
D. Horan, M. Louzir, P. Poilleux, I. Semeniouk, S. Wang
LLR, Ecole Polytechnique, CNRS/IN2P3, Palaiseau
D. Attié, D. Calvet, P. Colas, A. Delbart, P. Sizun
CEA, Irfu, CEA-Saclay, France
D. Götz
AIM, CEA/DSM-CNRS-Université Paris Diderot, France
IRFU/Service d’Astrophysique, CEA-Saclay, France
S. Amano, T. Kotaka, S. Hashimoto, Y. Minamiyama,
A. Takemoto, M. Yamaguchi, S. Miyamoto
LASTI, University of Hyôgo, Japan
S. Daté, H. Ohkuma
JASRI/SPring8, Japan
Primary author
Dr
Philippe Gros
(LLR, Ecole Polytechnique)
