Search Publications
Primordial black holes in SB SUSY Gauss-Bonnet inflation
Ashrafzadeh, A.; Solbi, M.; Heydari, S. +1 more
Here, we explore the formation of primordial black holes (PBHs) within a scalar field inflationary model coupled to the Gauss-Bonnet (GB) term, incorporating the low-scale spontaneously broken supersymmetric (SB SUSY) potential. The coupling function amplifies the curvature perturbations, consequently leading to the formation of PBHs and detectabl…
21cm signal sensitivity to dark matter decay
Qin, Y.; Mesinger, A.; Facchinetti, G. +1 more
The redshifted 21cm signal from the Cosmic Dawn is expected to provide unprecedented insights into early Universe astrophysics and cosmology. Here we explore how dark matter can heat the intergalactic medium before the first galaxies, leaving a distinctive imprint in the 21cm power spectrum. We provide the first dedicated Fisher matrix forecasts o…
Hard X-ray emission from blazars associated with high-energy neutrinos
Lutovinov, A. A.; Starobinsky, A. A.; Burenin, R. A. +4 more
Bright blazars were found to be prominent neutrino sources, and a number of IceCube events were associated with them. Evaluating high-energy photon emission of such blazars is crucial for better understanding of the processes and regions where neutrinos are produced. Here, we focus on hard X-ray emission observed by the SRG/ART-XC telescope, by th…
Revisiting bounds on primordial black hole as dark matter with X-ray background
Tan, Xiu-Hui; Xia, Jun-Qing
Within the mass range of 1016 - 5 × 1018 g, primordial black holes (PBHs) persist as plausible candidates for dark matter. Our study involves a reassessment of the constraints on PBHs through a comparative analysis of the cosmic X-ray background (CXB) and the emissions arising from their Hawking evaporation. We identify previ…
A pilot search for MeV gamma-ray emission from five galaxy clusters using archival COMPTEL data
Manna, Siddhant; Desai, Shantanu
We search for MeV gamma-ray emission between 0.75–30 MeV from five galaxy clusters, viz. Coma, VIRGO, SPT-CL J2012-5649, Bullet, and El Gordo, using archival data from the COMPTEL telescope. For this purpose we use three search templates: point source, radial disk and radial Gaussian. We do not detect any signals from Coma, SPT-CL J2012-5649, Bull…
Results of the follow-up of ANTARES neutrino alerts
Cenko, S. B.; André, M.; Chaty, S. +188 more
High-energy neutrinos could be produced in the interaction of charged cosmic rays with matter or radiation surrounding astrophysical sources. To look for transient sources associated with neutrino emission, a follow-up program of neutrino alerts has been operating within the ANTARES collaboration since 2009. This program, named TAToO, has triggere…
Development of generic no-scale inflation
Wu, Lina; Shen, Jin-Ke; Li, Tianjun +1 more
We develop generalized no-scale supergravity models of inflation, and then study the corresponding cosmological predictions as well as the formation of primordial black holes (PBHs) and scalar-induced gravitational waves (SIGWs). With a new parameter 0 < a ≤ 1, the generalized no-scale supergravity provides the continuous connections among the …
Putting all the X in one basket: Updated X-ray constraints on sub-GeV Dark Matter
Pinetti, Elena; Fornengo, Nicolao; Cirelli, Marco +2 more
Sub-GeV dark matter particles can annihilate or decay producing e ± pairs which upscatter the low-energy photon fields in the Galaxy and generate an X-ray emission (via the Inverse Compton effect). Using X-ray data from XMM-NEWTON, INTEGRAL, NUSTAR and SUZAKU, we derive new constraints on this class of dark matter (DM). In the annihilat…
Updated constraints on primordial black hole evaporation
Korwar, Mrunal; Profumo, Stefano
The Hawking evaporation process, leading to the production of detectable particle species, constrains the abundance of light black holes, presumably of primordial origin. Here, we reconsider and correct constraints from soft gamma-ray observations, including of the gamma-ray line, at 511 keV, produced by electron-positron pair-annihilation, where …
The morphology of exciting dark matter and the galactic 511 keV signal
Vincent, Aaron C.; Cappiello, Christopher V.; Jafs, Michael
We study the morphology of the 511 keV signal that could be produced by exciting dark matter (XDM) in the Milky Way. In this model, collisions between dark matter particles excite the dark matter to a state that can then decay back to the ground state, releasing an electron-positron pair. These electrons and positrons would then annihilate, produc…