1. Probing dark matter and fundamental physics with the Cherenkov Telescope ArrayFabio Iocco, Manuel Meyer, M. Doro, Werner Hofmann, Judit Pérez Romero, Gabrijela Zaharijas, A. Aguirre-Santaella, E. Amato, E. O. Angüner, Christopher Eckner, 2021, drugi sestavni deli Opis: Astrophysical observations provide strong evidence that more than 80% of all matter in the Universe is in the form of dark matter (DM). Two leading candidates of particles beyond the Standard Model that could constitute all or a fraction of the DM content are the so-called Weakly Interacting Massive Particles (WIMPs) and Axion-Like Particles (ALPs). The upcoming Cherenkov Telescope Array, which will observe gamma rays between 20 GeV and 300 TeV with unprecedented sensitivity, will have unique capabilities to search for these DM candidates. A particularly promising target for WIMP searches is the Galactic Center. WIMPs with annihilation cross sections correctly producing the DM relic density will be detectable with CTA, assuming an Einasto-like density profile and WIMP masses between 200 GeV and 10 TeV. Regarding new physics beyond DM, CTA observations will also enable tests of fundamental symmetries of nature such as Lorentz invariance. Ključne besede: dark matter, weakly interacting massive particles, axion-like particles, fundamental physics, Lorentz invariance, Cherenkov Telescope Array Observatory Objavljeno v RUNG: 09.01.2025; Ogledov: 184; Prenosov: 4 Celotno besedilo (6,31 MB) Gradivo ima več datotek! Več... |
2. Testing cosmology and fundamental physics with the Cherenkov Telescope ArrayH. Martínez-Huerta, Christopher Eckner, Gašper Kukec Mezek, Samo Stanič, Serguei Vorobiov, Lili Yang, Gabrijela Zaharijas, Danilo Zavrtanik, Marko Zavrtanik, Lukas Zehrer, 2019, objavljeni znanstveni prispevek na konferenci Opis: The Cherenkov Telescope Array (CTA) is the next generation ground-based observatory for γ-ray astronomy at energies above 30 GeV. Thanks to its unique capabilities, CTA observations will
address a plethora of open questions in astrophysics, ranging from the origin of cosmic messengers to the exploration of the frontiers of physics. In this note, we present a comprehensive sensitivity study to assess the potential of CTA to measure the γ-ray absorption on the extragalactic background light (EBL), to constrain or detect intergalactic magnetic fields (IGMFs), and probe physics beyond the standard model such as axion-like particles (ALPs) and Lorentz invariance violation (LIV), which could modify the γ-ray spectra features expected from EBL absorption. Our results suggest that CTA will have unprecedented sensitivity to detect IGMF signatures and will probe so-far unexplored regions of the LIV and ALP parameter space. Furthermore, an indirect measurement of the EBL and of its evolution will be performed with unrivaled precision. Ključne besede: very-high-energy gamma rays, the Cherenkov Telescope Array (CTA) Observatory, extragalactic background light (EBL), intergalactic magnetic fields (IGMFs), axion-like particles (ALPs), Lorentz invariance violation (LIV) Objavljeno v RUNG: 07.11.2024; Ogledov: 389; Prenosov: 4 Celotno besedilo (739,83 KB) Gradivo ima več datotek! Več... |
3. Search for Axionlike-Particle-Induced Prompt γ -Ray Emission from Extragalactic Core-Collapse Supernovae with the Fermi Large Area TelescopeManuel Meyer, Tanja Petrushevska, 2020, izvirni znanstveni članek Opis: During a core-collapse supernova (SN), axionlike particles (ALPs) could be produced through the Primakoff process and subsequently convert into γ rays in the magnetic field of the Milky Way. We do not find evidence for such a γ-ray burst in observations of extragalactic SNe with the Fermi Large Area Telescope (LAT). The SN explosion times are estimated from optical light curves and we find a probability of about ∼90% that the LAT observed at least one SN at the time of the core collapse. Under the assumption that at least one SN was contained within the LAT field of view, we exclude photon-ALP couplings ≳2.6×10−12 GeV−1 for ALP masses ma≲3×10−10 eV, improving previous limits from SN1987A by a factor of 2. Ključne besede: darn matter, axions, axion-like particles, core-collapse supernovae Objavljeno v RUNG: 15.06.2020; Ogledov: 3607; Prenosov: 84 Celotno besedilo (30,47 MB) |