Related papers: Probing super-heavy dark matter with ultra-high-en…
We revisit constraints on decaying very heavy dark matter (VHDM) using the latest ultrahigh-energy cosmic-ray (UHECR; $E\gtrsim 10^{18}$ eV) data and ultrahigh-energy (UHE) $\gamma$-ray flux upper limits, measured by the Pierre Auger…
The purely gravitational evidence supporting the need for dark matter (DM) particles is compelling and based on Galactic to cosmological scale observations. Thus far, the promising weakly interacting massive particles scenarios have eluded…
We consider decaying dark matter with masses $10^{7} \lesssim M \lesssim 10^{16}$ GeV, as a source of ultra-high energy (UHE) gamma rays. Using recent limits on UHE gamma-ray flux for energies $E_\gamma > 2 \cdot 10^{14}$ eV, provided by…
Among the several strategies for indirect searches of dark matter, one very promising one is to look for the gamma-rays from decaying dark matter. Here we use the most up-to-date upper bounds on the gamma-ray flux from $10^5$ to $10^{11}$…
In 15 years of data taking the Pierre Auger Observatory has observed no events beyond $10^{11.3}$ GeV. This null result translates into an upper bound on the flux of ultrahigh-energy cosmic rays implying $J (> 10^{11.3}$ GeV) $< 3.6 \times…
At any epoch, particle physics must be open to completely unexpected discoveries, and that is reason enough to extend the reach of searches for ultra-high energy (UHE) photons. The observation of a population of photons with energies $E…
Dwarf spheroidal galaxies are compact stellar objects with small or negligible astrophysical backgrounds, widely considered as promising targets to search for a signal from the dark matter decay and annihilation. We present constraints on…
Superheavy particles are a natural candidate for the dark matter in the universe and our galaxy, because they are produced generically during inflation in cosmologically interesting amounts. The most attractive model for the origin of…
For decades, searches for electroweak-scale dark matter (DM) have been performed without a definitive detection. This lack of success may hint that DM searches have focused on the wrong mass range. A proposed candidate beyond the canonical…
In the present paper, it is assumed that there exist two dark matter particles: superheavy dark matter particles (SHDM), whose mass $\sim$ inflaton mass, and light fermion dark matter (DM) particles which are the ultrahigh energy (UHE)…
We consider multi-messenger constraints on very heavy dark matter (VHDM) from recent Fermi gamma-ray and IceCube neutrino observations of isotropic background radiation. Fermi data on the diffuse gamma-ray background (DGB) shows a possible…
In the present paper, it is assumed that there exist two dark matter particles: superheavy dark matter particles (SHDM), whose mass $\sim$ inflaton mass, and lighter fermion dark matter particles (LFDM) which are the ultra-relativistic…
The recently observed ultra-high energy (UHE) cosmic rays beyond the Greisen-Zatsepin-Kuzmin bound can be explained by the decays of some superheavy $X$ particles forming a part of dark matter in our universe. We consider various discrete…
Next-generation ultra-high-energy (UHE) neutrino telescopes, presently under planning, will have the potential to probe the decay of heavy dark matter (DM) into UHE neutrinos, with energies in excess of $10^7$~GeV. Yet, this potential may…
We examine the role of the large--scale anisotropy of the high--energy cosmic ray distribution in a search for the heavy decaying dark matter (DM) signal. Using recent anisotropy measurements from the extensive air shower (EAS)…
Dark matter particles could be superheavy (mass $M_X\gtrsim10^9~$GeV) provided that their lifetime $\tau_X$ is extremely long, i.e. greater than $\simeq 10^{22}~$yr. Such stringent constraints on $\tau_X$ are generally obtained by limiting…
Superheavy particles of masses $\simeq 10^{13}-10^{14} GeV$ with lifetimes $\simeq 10^{10}-10^{22} years$ are very interesting, since their decays may account for the ultra-high energy (UHE) cosmic rays discovered beyond the…
Recent experiments have measured the Galactic $\gamma$-ray diffuse emission up to PeV energies, opening a window to study acceleration of Galactic cosmic rays and their propagation up to the cosmic-ray knee. Furthermore, these observations…
We present constraints on decaying and annihilating dark matter (DM) in the 4 keV to 10 GeV mass range, using published results from the satellites HEAO-1, INTEGRAL, COMPTEL, EGRET, and the Fermi Gamma-ray Space Telescope. We derive…
In this work we try to search for signals generated by ultra-heavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible gamma-ray by dark matter annihilation or decay from 16 dwarf spheroidal…