Search Publications
Gamma rays from dark matter spikes in EAGLE simulations
Peletier, R. F.; Horns, D.; Moulin, E. +3 more
Intermediate Mass Black Holes (IMBHs) with a mass range between 100 M⊙ and 106 M⊙ are expected to be surrounded by high dark matter densities, so-called dark matter spikes. The high density of self-annihilating Weakly Interacting Massive Particles (WIMPs) in these spikes leads to copious gamma-ray production. Suffi…
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…
Observing gravitational waves with solar system astrometry
Mentasti, G.; Contaldi, C. R.
The subtle influence of gravitational waves on the apparent positioning of celestial bodies offers novel observational windows [1,2,3,4]. We calculate the expected astrometric signal induced by an isotropic Stochastic Gravitational Wave Background (SGWB) in the short distance limit. Our focus is on the resultant proper motion of Solar System objec…
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…
Model-independent reconstruction of UV luminosity function and reionization epoch
Hazra, Dhiraj Kumar; Adak, Debabrata; Mitra, Sourav +1 more
We conduct a first comprehensive study of the Luminosity Function (LF) using a non-parametric approach. We use Gaussian Process to fit available luminosity data between redshifts z ∼ 2-8. Our free-form LF in the non-parametric approach rules out the conventional Schechter function model to describe the abundance-magnitude relation at redshifts z=3…
Wide binaries and modified gravity (MOG)
Moffat, J. W.
Wide binary stars are used to test the modified gravity called Scalar-Tensor-Vector Gravity or MOG. This theory is based on the additional gravitational degrees of freedom, the scalar field G = GN (1+α), where GN is Newton's constant, and the massive (spin-1 graviton) vector field ϕµ . The wide binaries have …
The glow of axion quark nugget dark matter. Part I. Large scale structures
Dolag, Klaus; Van Waerbeke, Ludovic; Sommer, Julian S. +5 more
Axion quark nuggets (AQN) are hypothetical, macroscopically large objects with a mass greater than a few grams and sub-micrometer size, formed during the quark-hadron transition. Originating from the axion field, they offer a possible resolution of the similarity between visible and dark components of the Universe, i.e. ΩDM ∼ Ωvisi…
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 …