Cosmology 2023 in Miramare

Session

Parallel

1 Sept 2023, 15:00

Main Auditorium (SISSA Building, Miramare, Trieste, Italy)

139. Primordial Black Holes during the QCD phase-transition

Ilia Musco

01/09/2023, 15:00

Primordial black holes (PBHs) could have been formed in the very early Universe from large amplitude perturbations of the metric. Their formation is naturally enhanced during the quark-hadron phase transition, because of the softening of the equation of state: at a scale between 1 and 3 solar masses, the threshold is reduced of about 10% with a corresponding abundance of PBHs significantly...

146. THERMAL QCD AXION PRODUCTION FROM THE EARLY UNIVERSE

Alessio Notari

01/09/2023, 15:00

The axion is a hypothetical new particle that could explain the absence of CP violation in QCD and has a very rich cosmological phenomenology. In particular a population of thermally produced axions is expected to exist, in addition to a cold dark matter population. I discuss a new conservative bound on the axion mass, from production in the early universe through scattering with pions below...

147. Prospects for blind CMB B-Modes reconstruction in future experiments

Alessandro Carones

01/09/2023, 15:25

Cosmology is now entering into the era of high-sensitivity CMB polarization experiments, which will target the detection of primordial B-modes to definitively prove the cosmic inflation scenario. Such signal is predicted to be much lower than the polarized Galactic emission (foregrounds) in any region of the sky pointing to the need for effective component separation methods. Given our current...

140. Stochastic Multiple Fields Inflation and Primordial Black Holes Formation

Kosar Asadi

01/09/2023, 15:25

There has been a revival of interest in PBHs in recent years, especially after the discovery of gravitational waves from merging black holes with mass at the order of tens of solar masses in the LIGO/Virgo observations. As black holes with this range of mass may not form from the known astrophysical processes, it is argued that these objects may indeed be PBHs. On the other hand, PBHs are...

148. Mimetic Inflation and Self-reproduction

Mariam Khaldieh

01/09/2023, 15:50

We present a model in which the problem of self-reproduction can be easily avoided in the inflationary universe, even when inflation starts at Planck scales. This is achieved by a simple coupling of the inflaton potential with a mimetic field. In this case, the problem of fine-tuning of the initial conditions does not arise, while eternal inflation and the multiverse with all their widely...

141. The early growth of massive galaxies and how it is shaped by black hole feedback

Manuela Bischetti

01/09/2023, 15:50

Quasars shining during the Reionization epoch are ideal targets to investigate the early growth phases of massive galaxies and of the supermassive black holes located at their nuclei. I will present state-of-the-art near-infrared and millimeter observations, respectively probing the nuclear and host-galaxy properties in these systems, back to the earliest epochs (z~7.5). I will show that...

149. Cosmological Constraints on Beyond Standard Model Neutrino Physics

Daniela Kirilova (Unknown), Daniela Kirilova (Institute of Astronomy and NAO, Bulgarian Academy of Sciences)

01/09/2023, 16:15

We present updated cosmological nucleosynthesis constraints on several models of neutrino beyond Standard Model Physics. Namely, first on the basis of the recent precise determination of the primordial abundance of He-4 we have updated the cosmological consraints on electron-sterile neutrino oscillations parameters. Second. we derive cosmological constraint on the lepton asymmetry in the model...

142. Highlights from the Pierre Auger Observatory

Ruben Mauricio Da Silva Conceicao (LIP - Laboratorio de Instrumentação e Física Experimental de Partículas (PT))

01/09/2023, 16:15

The Pierre Auger Observatory is the world's largest scientific facility dedicated to studying ultra-high-energy cosmic rays (UHECRs). In the past nearly twenty years of activity, the Pierre Auger Collaboration has investigated the origin and nature of the most energetic particles ever observed by humankind. The detection of UHECRs, with such scarce fluxes, is only possible indirectly through...

143. A new channel for supermassive black hole formation

Carlos Argüelles

01/09/2023, 17:00

Observations support the idea that supermassive black holes (SMBHs) power the emission at the center of active galaxies. However, contrary to stellar-mass BHs, there is a poor understanding of their origin and physical formation channel. In this talk, we propose a new process of SMBH formation in the early Universe that is not associated with baryonic matter (massive stars) or primordial...

150. Fundamental physics using high resolution quasar spectroscopy

Dinko Milakovic (IFPU)

01/09/2023, 17:00

Observations imply that only 5% of the total energy of the universe is in the form of baryonic matter. The remaining 95% is dark matter (e.g. undiscovered particles) and dark energy (e.g. the cosmological constant, a new scalar field of nature). Ongoing and future research is expected to either reveal the nature of the dark sector or revise our fundamental theories. Astronomical observations...

151. New Bounds on Monopoles from Intergalactic Magnetic Fields

Daniele Perri (SISSA Trieste, Trieste)

01/09/2023, 17:25

Monopoles are inevitable predictions of GUT theories. They are produced during phase transitions in the early universe, but also mechanisms like Schwinger effect in strong magnetic fields could give relevant contributions to the monopole number density. I will show that from the detection of intergalactic magnetic fields we can infer additional bounds on the magnetic monopole flux. I will...

144. Supermassive black holes from Pop III.1 stars with dark matter self-annihilation and their gravitational wave background

Jasbir Singh

01/09/2023, 17:25

The origin of supermassive black holes (SMBHs) remains an open question in astrophysics. The presence of black holes more massive than a billion solar masses at high redshifts (𝑧 > 6) challenges many formation mechanisms. One particular mechanism, which invokes the collapse of Pop III.1 stars formed with the energy input from dark matter self-annihilation as seeds for SMBHs alleviates this...

152. A transitional Planck Mass exploration in light of cosmological tensions

Giampaolo Benevento

01/09/2023, 17:50

Deviations from the standard cosmological model ($\Lambda$CDM) at early times, specifically in the context of Early Dark Energy (EDE), have garnered attention in the cosmological community as a potential solution to the Hubble/sound horizon tension. These deviations can also be achieved through modifications of gravity, providing an alternative way to modify the expansion history and...

153. Impact of a ΛCDM extension on UHECRs

Janning Meinert (Bergische Universität Wuppertal)

01/09/2023, 18:15

The existing discrepancies between the observation of local and extraction of global cosmological parameters are driving the need for an extension of the ΛCDM cosmological model. A proposed extension called SU(2)CMB describes cosmic microwave background (CMB) photons with an SU(2) instead of a U(1) gauge group. This reduces some of these tensions (such as H0, Ω𝑚, 𝜎8), pushes the recombination...

138. Primordial black holes in the Galaxy dark matter halo

Marek Abramowicz

If primordial black holes exist in the Galaxy dark matter halo, they must collide with neutron stars, producing light black holes LBH. These LBH may be detected by microlensing. Collisions of LBH with stellar mass BH and neutron stars are detectable in gravitational waves by Ligo, Virgo and Kagra interferometers.

145. Properties and Morphology of Dual AGN in the ASTRID Simulation at z=2

Ms Ekaterine Dadiani

We examine the host galaxy morphologies for a sample of a few thousand dual AGN (both active supermassive black holes) with separation distances of 0.5 kpc to 30 kpc using the large volume, high resolution cosmological hydrodynamical simulation Astrid at z= 2. We employed a kinematic decomposition method to examine the morphologies of galaxies in our simulation by segregating star particles...