A decaying neutralino as dark matter and its gamma ray spectrum

Abstract

It is shown that a decaying neutralino in a supergravity unified framework is a viable candidate for dark matter. Such a situation arises in the presence of a hidden sector with ultraweak couplings to the visible sector where the neutralino can decay into the hidden sector's lightest supersymmetric particle (LSP) with a lifetime larger than the lifetime of the universe. We present a concrete model where the MSSM/SUGRA is extended to include a hidden sector comprised of $U(1{)}_{X_1}\times U(1{)}_{X_2}$ gauge sector and the LSP of the hidden sector is a neutralino which is lighter than the LSP neutralino of the visible sector. We compute the loop suppressed radiative decay of the visible sector neutralino into the neutralino of the hidden sector and show that the decay can occur with a lifetime larger than the age of the universe. The decaying neutralino can be probed by indirect detection experiments, specifically by its signature decay into the hidden sector neutralino and an energetic gamma ray photon. Such a gamma ray can be searched for with improved sensitivity at Fermi-LAT and by future experiments such as the Square Kilometer Array (SKA) and the Cherenkov Telescope Array (CTA). We present several benchmarks which have a natural suppression of the hadronic channels from dark matter annihilation and decays and consistent with measurements of the antiproton background.

29 pages, 3 tables and 4 figures

References in corpus (20)

• Observation of an anomalous positron abundance in the cosmic radiation
• The spectrum of isotropic diffuse gamma-ray emission between 100 MeV and 820 GeV
• The Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived From First-Year Fermi Large Area Telescope Data
• micrOMEGAs4.1: two dark matter candidates
• Weak Corrections are Relevant for Dark Matter Indirect Detection
• General Constraints on Dark Matter Decay from the Cosmic Microwave Background
• Constraining Very Heavy Dark Matter Using Diffuse Backgrounds of Neutrinos and Cascaded Gamma Rays
• INTEGRAL SPI All-Sky View in Soft Gamma Rays: Study of Point Source and Galactic Diffuse Emissions
• Non-universal gaugino masses from non-singlet F-terms in non-minimal unified models
• Model-Independent Bound on the Dark Matter Lifetime
• Sensitivity of the Cherenkov Telescope Array for probing cosmology and fundamental physics with gamma-ray propagation
• Cosmic Rays from Leptophilic Dark Matter Decay via Kinetic Mixing
• Circumscribing Late Dark Matter Decays Model Independently
• A fussy revisitation of antiprotons as a tool for Dark Matter searches
• SUSY-QCD effects on neutralino dark matter annihilation beyond scalar or gaugino mass unification
• Self-interacting hidden sector dark matter, small scale galaxy structure anomalies, and a dark force
• Decaying neutralino dark matter in anomalous $U(1{)}_H$ models
• Detecting hidden sector dark matter at HL-LHC and HE-LHC via long-lived stau decays
• Xenon-1T excess as a possible signal of a sub-GeV hidden sector dark matter
• A long-lived stop with freeze-in and freeze-out dark matter in the hidden sector

Cited by in corpus (4)

• A cosmologically consistent millicharged dark matter solution to the EDGES anomaly of possible string theory origin
• Analyzing the Hubble tension through hidden sector dynamics in the early universe
• Combined constraints on dark photons and discovery prospects at the LHC and the Forward Physics Facility
• A tower of hidden sectors: a general treatment and physics implications