Related papers: On the status of superheavy dark matter
Super Heavy quasi-stable particles are naturally produced in the early universe and could represent a substantial fraction of the Dark Matter: the so-called Super Heavy Dark Matter (SHDM). The decay of SHDM represents also a possible source…
Decay or annihilation products of superheavy dark matter (SHDM) could be responsible for the end of the Ultra-High Energy Cosmic Ray (UHECR) spectrum. In this case, the south array of the Pierre Auger Observatory should observe in the…
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…
Several explanations for the existence of Ultra High Energy Cosmic Rays invoke the idea that they originate from the decay of massive particles created in the reheating following inflation. It has been suggested that the decay products can…
We refine the constraints on the lifetime of decaying super-heavy dark matter particles (SHDM), with masses ranging from $10^7$ to $10^{15}$ GeV, by analyzing ultra-high-energy (UHE) gamma-ray data. Our approach involves an accurate…
Several explanations for the existence of Ultra High Energy Cosmic Rays (UHECR) invoke the idea that they originate from the decay of massive particles created in the reheating following inflation. It has been suggested that the decay…
The detection of High Energy Cosmic Rays (HECR) with energies around and beyond GZK expected cutoff has introduced the idea of existence of a decaying Ultra Heavy Dark Matter (UHDM). If this type of particles make a substantial part of the…
Models which associate the origin of the ultra-high energy cosmic rays (UHECR) with decays of relic superheavy particles predict the anisotropy of UHECR flux toward the Galactic center. We use the existing SUGAR data, which covered the…
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)…
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…
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…
Ultra-high energy cosmic rays (UHECRs) may originate from the decay of massive relic particles in the dark halo of the Galaxy, or they may be produced by supermassive black holes in the nuclei of nearby galaxies. The anisotropy in the…
Stable, quantized gravitational bound states of primordial black holes called Holeums could have been produced in the early universe and could be a component of the Super Heavy Dark Matter (SHDM) present in galactic halos. We show that…
Superheavy dark matter has been attractive as a candidate of particle dark matter. We propose a ``natural" particle model, in which the dark matter serves as the inflaton in natural inflation, while decaying to high-energy particles at…
The motivation and the current status of top-down models as sources of ultrahigh energy cosmic rays (UHECR) are reviewed. Stimulated by the AGASA excess, they were proposed as the main source of UHECRs beyond the GZK cutoff. Meanwhile…
In this paper we discuss the possible distortions of the ionization history of the universe caused by an injection of non-thermal energy due to decays of hypothetical Super Heavy Dark Matter (SHDM) particles. These particles are usually…
The current status of origin of Ultra High Energy Cosmic Rays (UHECR) is reviewed, with emphasis given to elementary particle solutions to UHECR problem, namely to Topological Defects and Super-Heavy Dark Matter (SHDM) particles. The relic…
Ultra-high-energy cosmic rays (UHECRs) are atomic nuclei from space with vastly higher energies than any other particles ever observed. Their origin and chemical composition remain a mystery. As we show here, the large- and…
Two of the greatest mysteries of modern physics are the origin of the dark matter in the universe and the nature of the highest energy particles in the cosmic ray spectrum. We discuss here possible direct and indirect connections between…
We propose the lightest supersymmetric particle (LSP) as a well-suited candidate for superheavy dark matter (SHDM). Various production mechanisms at the end of inflation can produce SHDM with the correct abundance, $\Omega_{LSP} h^2 \sim…