Item

Abstract

T
eV
γ
-ray astronomy is led by two main ground-based facilities: Imaging Atmospheric
Cherenkov Telescopes, and Water Cherenkov Detectors. This thesis focuses on H.E.S.S.,
an array of five Cherenkov telescopes, and HAWC, a wide field of view
γ
-ray observatory,
that are very complementary despite their technical differences.
Part of this thesis is dedicated to the HAWC high energy upgrade with the outrigger array
that was developed and deployed in the time frame of this Ph.D. I introduce the calibration for
the charge and time reconstruction of the photomultiplier tubes that equip each of the small
outrigger tanks.
I present a comparison of the galactic plane as seen by HAWC and H.E.S.S. in the region
where they overlap. I highlight the differences which arise from intrinsic properties of the
instruments and from their dedicated data analysis, and show that background estimation is
a major ingredient. The region of the galactic plane around the source 2HWC J1928+177 is
studied in more details. A multi-component fit is performed and the best fit model includes two
point sources for 2HWC J1930+188 and the new source HWC J1932+192, one extended source of
size
σ
=
0
.
17
°
for 2HWC J1928+177 and 2 extra extended sources that account for larger scale
emission.