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Related papers: Fermi-Dirac corrections to relic abundances

200 papers

We investigate the relic density n_\chi of non-relativistic long-lived or stable particles \chi in non-standard cosmological scenarios. We calculate the relic abundance starting from arbitrary initial temperatures of the radiation-dominated…

High Energy Physics - Phenomenology · Physics 2008-11-26 Manuel Drees , Hoernisa Iminniyaz , Mitsuru Kakizaki

We point out a correlation between the effective number of relativistic degrees of species $\Delta N_\text{eff}$, the cosmologically measured $m_{\nu,\text{sterile}}^{\text{eff}}$, and the terrestrially measured neutrino mass sum and…

High Energy Physics - Phenomenology · Physics 2021-10-27 Peter Adshead , Yanou Cui , Andrew J. Long , Michael Shamma

The existence of prolonged radiation domination prior to the Big Bang Nucleosynthesis (BBN), starting just after the inflationary epoch, is not yet established unanimously. If instead, the universe undergoes a non-standard cosmological…

High Energy Physics - Phenomenology · Physics 2022-10-05 Anirban Biswas , Dilip Kumar Ghosh , Dibyendu Nanda

Light thermal dark matter has emerged as an attractive theoretical possibility and a promising target for discovery at experiments in the near future. Such scenarios generically invoke mediators with very small couplings to the Standard…

High Energy Physics - Phenomenology · Physics 2025-02-24 Gopolang Mohlabeng , Adreja Mondol , Tim M. P. Tait

We calculate analytically the effective mass and the quasiparticle renormalization factor in an electron liquid with long-range Coulomb interactions between electrons in two and three dimensions in the leading order density expansion. We…

Strongly Correlated Electrons · Physics 2009-11-10 Victor Galitski , S. Das Sarma

The prediction of cross sections for nuclei far off stability is crucial in the field of nuclear astrophysics. In recent calculations the nuclear level density -- as an important ingredient to the statistical model (Hauser-Feshbach) -- has…

Astrophysics · Physics 2016-08-30 T. Rauscher , F. -K. Thielemann , K. -L. Kratz

We show that atomic Fermi mixtures with density and mass imbalance exhibit a rich diversity of scaling laws for the quasiparticle decay rate beyond the quadratic energy and temperature dependence of conventional Fermi liquids. For certain…

Quantum Gases · Physics 2013-10-03 Zhihao Lan , Georg M. Bruun , Carlos Lobo

Neutral vectorlike fermion as inspired by unified theories might become quasi-Dirac states at TeV due to a violation in lepton-like symmetry. It is shown that such quasi-Dirac fermions can properly achieve radiative neutrino mass generation…

High Energy Physics - Phenomenology · Physics 2026-03-16 Nguyen Thi Nguyet Nga , Nguyen Huy Thao , Phung Van Dong

Quantum corrections to Thomas-Fermi (TF) theory are investigated for noninteracting one-dimensional fermions with known uniform semiclassical approximations to the density and kinetic energy. Their structure is analyzed, and contributions…

Quantum Gases · Physics 2017-03-15 Raphael F. Ribeiro , Kieron Burke

The effect of strong quantising magnetic field on low density stellar matter is investigated using Thomas-Fermi-Dirac (TFD) model. The Wigner-Seitz cell structure is assumed for the low density matter. The significant changes in the…

Astrophysics · Physics 2007-05-23 Nandini Nag , Somenath Chakrabarty

We reexamine the evolution of thermal relic particle abundances for the case where the interaction rate depends on the particle velocities. For the case of Sommerfeld enhancement, we show that the standard analytic approximation, modified…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 James B. Dent , Sourish Dutta , Robert J. Scherrer

A Fokker-Planck type equation for interacting particles with exclusion principle is analysed. The nonlinear drift gives rise to mathematical difficulties in controlling moments of the distribution function. Assuming enough initial moments…

Analysis of PDEs · Mathematics 2008-01-21 José A. Carrillo , Philippe Laurençot , Jesús Rosado

It is shown that the experimentally observed decrease of the nuclear symmetry energy with the increasing centrality or the excitation energy in isotopic scaling analyses of heavy-ion reactions can be well understood analytically within a…

Nuclear Theory · Physics 2009-11-11 Bao-An Li , Lie-Wen Chen

It is known that the finite temperature and density (FTD) corrections increase the electron mass, charge and modify the properties of the emitted radiation. All the signals, travelling through the astronomical bodies, carry over the…

High Energy Physics - Phenomenology · Physics 2021-10-22 Samina Masood

Around one second after the big bang, neutrino decoupling and $e^+$-$e^-$ annihilation distort the Fermi-Dirac spectrum of neutrino energies. Assuming neutrinos have masses and can mix, we compute the distortions using nonequilibrium…

High Energy Physics - Phenomenology · Physics 2009-09-25 Alan Kostelecky , Stuart Samuel

Formulae for the energies of degenerate non-relativistic and ultra-relativistic Fermi gases play multiple roles in simple arguments related to the collapse of a stellar core to a neutron star. These formulae, deployed in conjunction with…

Astrophysics · Physics 2008-12-02 Christian Y. Cardall

Approximate analytical solutions of the Boltzmann equation for particles that are either extremely relativistic or non-relativistic when they decouple from the thermal bath are well established. However, no analytical formula for the relic…

High Energy Physics - Phenomenology · Physics 2009-09-02 Manuel Drees , Mitsuru Kakizaki , Suchita Kulkarni

The equation of state of an ideal Fermi gas is expressed in terms of Fermi-Dirac integrals. We give formulae for evaluation the Fermi-Dirac integrals of orders 1/2, 3/2, and 5/2 and their derivatives in various limits of non- and extreme…

Astrophysics · Physics 2009-10-28 Juan Antonio Miralles , Kenneth A. Van Riper

In some scenarios for the early universe, non-relativistic thermal dark matter chemically decouples from the thermal environment once the temperature drops well below the dark matter mass. The value at which the energy density freezes out…

High Energy Physics - Phenomenology · Physics 2025-01-09 Simone Biondini , Nora Brambilla , Andrii Dashko , Gramos Qerimi , Antonio Vairo

The annihilation of electron-positron pairs around one second after the big bang distorts the Fermi-Dirac spectrum of neutrino energies. We determine the distortions assuming neutrino mixing with an inverted neutrino-mass hierarchy.…

High Energy Physics - Phenomenology · Physics 2009-09-25 V. Alan Kostelecky , Stuart Samuel