Observations of the Sagittarius dwarf spheroidal (Sgr dSph) galaxy were carried out with the HESS array of four imaging air Cherenkov telescopes in June 2006. A total of 11 h of high quality data are available after data selection. There is no evidence for a very high energy γ-ray signal above the energy threshold at the target position. A 95% CL flux limit of 3.6 × 10- 12 cm- 2 s- 1 above 250 GeV has been derived. Constraints on the velocity-weighted cross-section 〈 σ v 〉 are calculated in the framework of dark matter particle annihilation using realistic models for the dark matter halo profile of Sagittarius dwarf galaxy. Two different models have been investigated encompassing a large class of halo types. A 95% CL exclusion limit on 〈 σ v 〉 of the order of 2 × 10- 25 cm3 s- 1 is obtained for a core profile in the 100 GeV-1 TeV neutralino mass range.
|Original language||English (US)|
|Number of pages||8|
|State||Published - Feb 2008|
Bibliographical noteFunding Information:
The support of the Namibian authorities and of the University of Namibia in facilitating the construction and operation of HESS is gratefully acknowledged, as is the support by the German Ministry for Education and Research (BMBF), the Max Planck Society, the French Ministry for Research, the CNRS-IN2P3 and the Astroparticle Interdisciplinary Programme of the CNRS, the UK Particle Physics and Astronomy Research Council (PPARC), the IPNP of the Charles University, the South African Department of Science and Technology and National Research Foundation, and by the University of Namibia. We appreciate the excellent work of the technical support staff in Berlin, Durham, Hamburg, Heildelberg, Palaiseau, Paris, Saclay, and in Namibia in the construction and operation of the equipment. We thank Edmond Giraud for suggestions and discussions concerning the Sagittarius dwarf Galaxy observations by HESS.
- Dark matter
- Dwarf spheroidal galaxy
- Gamma-rays: observations
ASJC Scopus subject areas
- Astronomy and Astrophysics