相关论文: Astrophysical uncertainties challenge 21-cm foreca…
The discoveries of a number of binary black hole mergers by LIGO and VIRGO has reinvigorated the interest that primordial black holes (PBHs) of tens of solar masses could contribute non-negligibly to the dark matter energy density. Should…
The 21 cm signal produced by non-evaporating primordial black holes (PBHs) is investigated. X-ray photons emitted by accretion of matter onto a PBH ionize and heat the intergalactic medium (IGM) gas near the PBH. Using a simple analytic…
Aims. This study investigates the role of primordial black holes (PBHs) in shaping cosmic radiation backgrounds--the cosmic X-ray background (CXB), the Lyman-Werner background (LWB), and the cosmic radio background (CRB)--and evaluates…
Evolution in the X-ray luminosity -- star formation rate ($L_X$-SFR) relation could provide the first evidence of a top-heavy stellar initial mass function in the early universe, as the abundance of high-mass stars and binary systems are…
Recently the Experiment to Detect the Global Epoch of Reionization Signature (EDGES) reported the detection of a 21cm absorption signal stronger than astrophysical expectations. In this paper we study the impact of radiation from dark…
Primordial black holes (PBHs) as part of the Dark Matter (DM) would modify the evolution of large-scale structures and the thermal history of the universe. Future 21 cm forest observations, sensitive to small scales and the thermal state of…
The recent observations of the global 21cm signal by EDGES and gravitational waves by LIGO/VIGO have revived interest in PBHs. Different from previous works, we investigate the influence of PBHs on the evolution of the IGM for the mass…
21-cm cosmology provides an exciting opportunity to probe new physics dynamics in the early universe. In particular, a tiny sub-component of dark matter that interacts strongly with the visible sector may cool the gas in the intergalactic…
The excess radio background seen at $\simeq 0.1-10\,{\rm GHz}$ has stimulated much scientific debate in the past years. Recently, it was pointed out that the soft photon emission from accreting primordial black holes may be able to explain…
21-cm radio signal has emerged as an important probe in investigating the dark age of the Universe (recombination to reionization). In the current analysis, we explore the combined effects of primordial black holes (PBH), cooling off of the…
Should Primordial Black Holes (PBHs) exist in nature, they would inevitably accrete baryonic matter in their vicinity. In turn, the consequent emission of high-energy radiation could affect the thermal history of the universe to an extent…
Fluctuations in high-redshift cosmic 21-cm radiation provide a new window for observing unconventional effects of high-energy physics in the primordial spectrum of density perturbations. In scenarios for which the initial state prior to…
Observations of the cosmic microwave background constrain the abundance of primordial black holes, as these would accrete gas and inject energy into the cosmological medium. We have revisited these constraints, taking into account the local…
Detection of the global 21 cm signal arising from neutral hydrogen can revolutionize our understanding of the standard evolution of the universe after recombination. In addition, it can also be an excellent probe of Dark Matter (DM). Among…
Measurements of the temperature of the baryons at the end of the cosmic dark ages can potentially set very precise constraints on energy injection from exotic sources, such as annihilation or decay of the dark matter. However, additional…
Primordial black hole production in the mass range $10-10^4 \,{\rm M_\odot}$ is motivated respectively by interpretations of the LIGO/Virgo observations of binary black hole mergers and by their ability to seed intermediate black holes…
The origin of observed extremely high energy cosmic rays remains an astrophysical enigma. We show that a single evaporating primordial black hole should produce 8.5*10^14 particles over a 10^20 eV threshold. This emission results from…
We investigate the effects of accretion of phantom energy onto primordial black holes. Since Hawking radiation and phantom energy accretion contribute to a {\it decrease} of the mass of the black hole, the primordial black hole that would…
Probing dark matter particles and primordial black holes remains a pivotal challenge in modern cosmology. Exotic energy injections from dark matter annihilation, decay, and PBH Hawking evaporation can alter the thermal and ionization…
The recent observation of the 21-cm absorption signal by the EDGES experiment provides a new observational window into the dynamics of the young Universe. Based on this result, we constrain the properties of ALPs and excited dark matter via…