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Related papers: The number density of a charged relic

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In models where the gravitino is the lightest supersymmetric particle (LSP), the next-to-lightest supersymmetric particle (NLSP) is long-lived. We consider an important charged NLSP candidate, the scalar tau $\tilde{\tau}$. Slow charged…

High Energy Physics - Phenomenology · Physics 2008-11-26 Koichi Hamaguchi , Yoshitaka Kuno , Tsuyoshi Nakaya , Mihoko M. Nojiri

Heavy-ion experiments provide a new opportunity to gain a deeper understanding of the structure of nuclei. To achieve this, it is crucial to identify observables under circumstances that are minimally affected by the process that leads to…

Nuclear Theory · Physics 2024-06-21 S. M. A. Tabatabaee , S. F. Taghavi

The elliptic flow in collisions of neutron-rich heavy-ion systems at intermediate energies emerges as an observable sensitive to the strength of the symmetry energy at supra-saturation densities. First results obtained by comparing ratios…

Nuclear Experiment · Physics 2014-02-06 W. Trautmann , H. H. Wolter

We present calculations showing how electron rest mass influences entropy flow, neutrino decoupling, and Big Bang Nucleosynthesis (BBN) in the early universe. To elucidate this physics and especially the sensitivity of BBN and related…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-05 E. Grohs , George M. Fuller

We extend the study of the effect of density perturbations to the well known thermal dark matter freeze-out scenario. We find $\sim 10 \, \%$ enhancements in the cross section are required to match onto the observed relic abundance for…

High Energy Physics - Phenomenology · Physics 2025-06-16 Iason Baldes , Ryusuke Jinno

The decays of massive gravitinos into neutralino dark matter particles and Standard Model secondaries during or after Big-Bang nucleosynthesis (BBN) may alter the primordial light-element abundances. We present here details of a new suite…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-08 Richard H. Cyburt , John Ellis , Brian D. Fields , Feng Luo , Keith A. Olive , Vassilis C. Spanos

We investigate the possible effect of the residual annihilations of heavy particles after freeze-out from equilibrium in the early universe. An error in previous work on this subject is pointed out and the correct method of solving the…

Astrophysics · Physics 2009-10-30 Steen Hannestad

In the primordial Big Bang nucleosynthesis (BBN), only the lightest nuclides (D, $^3$He, $^4$He, and $^7$Li) were synthesized in appreciable quantities, and these relics provide us a unique window on the early universe. Currently, BBN…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-23 J. J. He , S. Q. Hou , A. Parikh , D. Kahl , C. A. Bertulani , other collaborators

The Lightest Supersymmetric Particle (LSP) makes a good Dark Matter (DM) candidate, since its relic density quite naturally comes out close to the cosmologically required value. This is true even in minimal Supergravity models with…

High Energy Physics - Phenomenology · Physics 2009-09-25 M. Drees

The possibility that both the baryon asymmetry and dark matter arise from the late decay of a population of supersymmetric particles is considered. If the decay takes place below the LSP freeze out temperature, a nonthermal distribution of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Scott Thomas

Neutralinos arise as natural dark matter candidates in many supersymmetric extensions of the Standard Model. We present a novel calculation of the neutralino relic abundance in which we include all so called coannihilation processes between…

High Energy Physics - Phenomenology · Physics 2009-11-10 Joakim Edsjo , Mia Schelke , Piero Ullio , Paolo Gondolo

We perform calculations of dark photon production and decay in the early universe for ranges of dark photon masses and vacuum coupling with standard model photons. Simultaneously and self-consistently with dark photon production and decay,…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-05 Jung-Tsung Li , George M. Fuller , Evan Grohs

We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 Anthony Aguirre , Alberto Diez-Tejedor

Several scenarios beyond the Standard Model predict heavy long-lived particles as a result of a kinematic constraint, a conserved quantum number or a weak coupling. Such particles are possibly identified based on the detection through…

High Energy Physics - Experiment · Physics 2019-08-13 Shimpei Yamamoto

The isospin dependence of nuclear level density has been investigated by analyzing the spectra of evaporated neutrons from excited $^{116}$Sn and $^{116}$Te nuclei. These nuclei are populated via $p$ + $^{115}$In and $^{4}$He + $^{112}$Sn…

We consider the consequences for the relic neutrino abundance if extra neutrino interactions are allowed, e.g., the coupling of neutrinos to a light (compared to $m_\nu$) boson. For a wide range of couplings not excluded by other…

Astrophysics · Physics 2008-11-26 John F. Beacom , Nicole F. Bell , Scott Dodelson

The construction of a Supersymmetric Grand Unified Model based on the Pati-Salam gauge group is briefly reviewed and the low energy consequences of the derived asymptotic Yukawa quasi-unification conditions are examined. In the framework of…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Pallis , M. E. Gomez

The first measurement of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}}$ = 2.76 TeV is presented. For an event sample corresponding to the most…

Nuclear Experiment · Physics 2017-10-02 ALICE Collaboration

We discuss the scenario where the gravitino is the lightest supersymmetric particle and the long-lived next-to-lightest sparticle (NSP) is the neutralino or the stau, the charged partner of the tau lepton. In this case staus form bound…

High Energy Physics - Phenomenology · Physics 2007-10-30 Vassilis C. Spanos

We consider Bose-Einstein condensation of massive electrically charged scalars in a uniform background of charged fermions. We focus on the case when the scalar condensate screens the background charge, while the net charge of the system…

High Energy Physics - Theory · Physics 2008-11-26 Gregory Gabadadze , Rachel A. Rosen