Results 71 to 80 of about 84,925 (237)

Dark Energy From the Gravitational Wave Background With Scalar Field Dark Matter

Astronomische Nachrichten, Volume 346, Issue 3-4, March-May 2025.
ABSTRACT Recent observational results, such as those from pulsar timing arrays (PTA), suggest a low‐frequency Gravitational Wave Background (GWB) permeates our universe. This opens the possibility that gravitational waves could span a broader spectrum, potentially impacting cosmological scales.
Edwin L. Pérez‐Ochoa, Tonatiuh Matos
wiley   +1 more source

On the axial-vector form factor of the nucleon and chiral symmetry

European Physical Journal C: Particles and Fields, 2020
We consider the chiral Lagrangian with nucleon, isobar, and pion degrees of freedom. The baryon masses and the axial-vector form factor of the nucleon are derived at the one-loop level.
Matthias F. M. Lutz, Ulrich Sauerwein, Rob G. E. Timmermans   +2 more
doaj   +1 more source

Baryons and Their Halos [PDF]

AIP Conference Proceedings, 2010
Galaxies are composed of baryonic stars and gas embedded in dark matter halos. Here I briefly review two aspects of the connection between baryons and their halos. (1) The observed baryon content of galaxies falls short of the cosmic baryon fraction by an amount that varies systematically with mass. Where these missing baryons now reside is unclear. (2)
Stacy McGaugh, Victor P. Debattista, C. C. Popescu   +2 more
openaire   +4 more sources

Euler–Heisenberg Black Hole Surrounded by Quintessence in the Background of Perfect Fluid Dark Matter: Thermodynamics, Shadows, and Quasinormal Modes

Fortschritte der Physik, Volume 73, Issue 3, March 2025.
Abstract Current observations show that a significant fraction of the Universe is composed of dark energy and dark matter. In this paper, the simultaneous effects of these dark sectors on the Euler–Heisenberg black hole are investigated, using the quintessence matter field and perfect fluid to model them. In particular, the black hole's thermodynamics,
Bilel Hamil, Bekir Can Lütfüoğlu
wiley   +1 more source

Visible GeV ALP from TeV Vector‐Like Leptons

Fortschritte der Physik, Volume 73, Issue 3, March 2025.
Abstract A model is presented where a GeV axion‐like‐particle (ALP) is predicted in a large portion of the parameter space due to the presence of explicit Peccei–Quinn (PQ) symmetry‐breaking terms in an exotic leptonic sector. The latter provides a solution to the muon g−2$g-2$ anomaly, within the framework of the Linear Seesaw neutrino mechanism.
Arturo de Giorgi, Marta Fuentes Zamoro, Luca Merlo   +2 more
wiley   +1 more source

Natural mass hierarchy among three heavy Majorana neutrinos for resonant leptogenesis under modular A 4 symmetry

Journal of High Energy Physics, 2022
It is clear that matter is dominant in the Universe compared to antimatter. We call this problem baryon asymmetry. The baryon asymmetry is experimentally determined by both cosmic microwave background and big bang nucleosynthesis measurements. To resolve
Dong Woo Kang, Jongkuk Kim, Takaaki Nomura, Hiroshi Okada   +3 more
doaj   +1 more source

Recent Developments in Degenerate Higher Order Scalar Tensor Theories

Annalen der Physik, Volume 537, Issue 2, February 2025.
Degenerate Higher Order Scalar Tensor theories are reviewed, together with their applications in cosmology and astrophysics. These theories have been applied to build models of the early universe, in the description of the late‐time cosmic acceleration, as well as in astrophysics, including black hole physics. They have the potential to provide answers
Andrei Lazanu
wiley   +1 more source

Recent results of Baryon electromagnetic form factors at BESIII [PDF]

EPJ Web of Conferences
Baryon Electromagnetic Form Factors are essential for testing ground state models of nucleon internal structures. At the BESIII experiment, a comprehensive study has been conducted on the electromagnetic form factors of various baryons.
Xia Lei
doaj   +1 more source

Possible molecular dibaryons with csssqq quarks and their baryon–antibaryon partners

European Physical Journal C: Particles and Fields, 2023
In this work, we systematically investigate the charmed–strange dibaryon systems with csssqq quarks and their baryon–antibaryon partners from the interactions $$\varXi ^{(',*)}_{c}\varXi ^{(*)}$$ Ξ c ( ′ , ∗ ) Ξ ( ∗ ) , $$\varOmega ^{(*)}_c\varLambda ...
Shu-Yi Kong, Jun-Tao Zhu, Jun He
doaj   +1 more source

A Brief, Biased View of Neutron Star Cooling

Astronomische Nachrichten, Volume 346, Issue 1, January 2025.
ABSTRACT This is a concise and non‐technical review of topics related to neutron star (NS) cooling, for both young NSs and NSs in low‐mass x‐ray binaries. Neutrino emission from the NS core drives cooling rates, via different processes including Urca processes and pair breaking and formation at the neutron superfluid critical temperature.
Craig Heinke
wiley   +1 more source