Search for dark matter signals towards a selection of recently-detected DES dwarf galaxy satellites of the Milky Way with H.E.S.S

Abstract

Dwarf spheroidal galaxy satellites of the Milky Way are prime targets for indirect detection of dark matter with gamma rays due to their proximity, high dark matter content and absence of non-thermal emission processes. Recently, the Dark Energy Survey (DES) revealed the existence of new ultra-faint dwarf spheroidal galaxies in the southern-hemisphere sky, therefore ideally located for ground-based observations with the imaging atmospheric Cherenkov telescope array H.E.S.S. We present a search for very-high-energy ($E\gtrsim 100$ GeV) gamma-ray emission using H.E.S.S. observations carried out recently towards Reticulum II, Tucana II, Tucana III, Tucana IV and Grus II satellites. No significant very-high-energy gamma-ray excess is found from the observations on any individual object nor in the combined analysis of all the datasets. Using the most recent modeling of the dark matter distribution in the dwarf galaxy halo, we compute for the first time on DES satellites individual and combined constraints from Cherenkov telescope observations on the annihilation cross section of dark matter particles in the form of Weakly Interacting Massive Particles. The combined 95% C.L. observed upper limits reach $⟨\sigma v⟩\simeq 1\times 10^{-23}$ cm${}^3$s${}^{-1}$ in the $W^{+}{W}^{-}$ channel and $4\times 10^{-26}$ cm${}^3$s${}^{-1}$ in the $\gamma \gamma$ channels for a dark matter mass of 1.5 TeV. The H.E.S.S. constraints well complement the results from Fermi-LAT, HAWC, MAGIC and VERITAS and are currently the most stringent in the $\gamma \gamma$ channels in the multi-GeV/multi-TeV mass range.

20 pages, 12 figures

References in corpus (10)

• Observations of the Crab Nebula with H.E.S.S
• Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way Companions
• Precise Relic WIMP Abundance and its Impact on Searches for Dark Matter Annihilation
• Beasts of the Southern Wild: Discovery of nine Ultra Faint satellites in the vicinity of the Magellanic Clouds
• Searching for Dark Matter Annihilation in Recently Discovered Milky Way Satellites with Fermi-LAT
• Background Modelling in Very-High-Energy gamma-ray Astronomy
• Dwarf galaxy annihilation and decay emission profiles for dark matter experiments
• Search for dark matter annihilation signatures in H.E.S.S. observations of Dwarf Spheroidal Galaxies
• Spherical Jeans analysis for dark matter indirect detection in dwarf spheroidal galaxies - Impact of physical parameters and triaxiality
• Estimating the GeV Emission of Millisecond Pulsars in Dwarf Spheroidal Galaxies

Cited by in corpus (32)

• Combined searches for dark matter in dwarf spheroidal galaxies observed with the MAGIC telescopes, including new data from Coma Berenices and Draco
• Les Houches Lectures on Indirect Detection of Dark Matter
• Detection of extended gamma-ray emission around the Geminga pulsar with H.E.S.S
• Velocity-dependent J-factors for annihilation radiation from cosmological simulations
• Search for Ultraheavy Dark Matter from Observations of Dwarf Spheroidal Galaxies with VERITAS
• Search for dark matter annihilation in the dwarf irregular galaxy WLM with H.E.S.S
• Toward the ultimate reach of current imaging atmospheric Cherenkov telescopes and their sensitivity to TeV dark matter
• Dark Matter Line Searches with the Cherenkov Telescope Array
• TeV Dark Matter Searches in the Extragalactic Gamma-Ray Sky
• Constraints on dark matter annihilation and decay from the large-scale structure of the nearby universe
• Dark Matter and $(g-2{)}_{\mu ,e}$ in radiative Dirac neutrino mass models
• Sensitivity of the Cherenkov Telescope Array to dark subhalos
• Asymmetric accidental composite dark matter
• Galactic and Extragalactic Sources of Very High Energy Gamma-rays
• Multi-TeV dark matter density in the inner Milky Way halo: spectral and dynamical constraints
• Leptoquarks and Real Singlets: A Richer Scalar Sector Behind the Origin of Dark Matter
• Gamma-ray and Synchrotron Radiation from Dark Matter annihilations in Ultra-faint Dwarf Galaxies
• New dark matter analysis of Milky Way dwarf satellite galaxies with MADHATv2
• Dark matter indirect detection limits from complete annihilation patterns
• CTA Sensitivity on TeV scale Dark Matter Models with Complementary Limits from Direct Detection
• Gamma rays from dark matter spikes in EAGLE simulations
• Present and Future constraints on Secluded Dark Matter in the Galactic Halo with TeV Gamma-ray Observatories
• Combined dark matter search towards dwarf spheroidal galaxies with Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS
• Velocity-dependent J-factors for Milky Way dwarf spheroidal analogues in cosmological simulations
• Estimate of the Mass and Radial Profile of the Orphan-Chenab Stream's Dwarf Galaxy Progenitor Using MilkyWay@home
• The dark Stodolsky effect: constraining effective dark matter operators with spin-dependent interactions
• Electroweak Dark Matter
• Dark Matter and Fundamental Physics Searches with IACTs
• H.E.S.S.: The High Energy Stereoscopic System
• Limiting the Heavy-quark and Gluon-philic Real Dark Matter
• Search for gamma-ray spectral lines from dark matter annihilation with the H.E.S.S. Inner Galaxy Survey
• Magellan/IMACS spectroscopy of Grus I: A low metallicity ultra-faint dwarf galaxy