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Related papers: Neutralino Relic Density Enhancement in Non-Standa…

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Standard simple assumptions are usually made about the pre-Big Bang Nucleosynthesis epoch, from which we do not have observations. Modifying these assumptions, the predicted density of relic particles such as neutralinos and sterile…

High Energy Physics - Phenomenology · Physics 2008-05-14 Graciela B. Gelmini

We show that the relic abundance of the minority component of asymmetric dark matter can be very sensitive to the expansion rate of the Universe and the temperature of transition between a non-standard pre-Big Bang Nucleosynthesis…

High Energy Physics - Phenomenology · Physics 2015-06-15 Graciela B. Gelmini , Ji-Haeng Huh , Thomas Rehagen

If the energy density of the Universe before nucleosynthesis is dominated by a scalar field phi that decays and reheats the plasma to a temperature T_{RH} smaller than the standard neutralino freeze out temperature, the neutralino relic…

High Energy Physics - Phenomenology · Physics 2009-11-11 Graciela Gelmini , Paolo Gondolo , Adrian Soldatenko , Carlos E. Yaguna

We compute the neutralino relic density in the minimal supersymmetric standard model by using exact expressions for the neutralino annihilation cross section into all tree-level final states, including all contributions and interference…

High Energy Physics - Phenomenology · Physics 2010-02-03 Takeshi Nihei , Leszek Roszkowski , Roberto Ruiz de Austri

We analyse the relic neutralino density in supersymmetric models with an intermediate unification scale. In particular, we present concrete cosmological scenarios where the reheating temperature is as small as $\cal{O}$ $1 - 1000$ MeV).…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Khalil , C. Munoz , E. Torrente-Lujan

Standard lore states that there is tension between the need to accommodate the relic density of a weakly interacting massive particle and direct searches for dark matter. However, the estimation of the relic density rests on an…

High Energy Physics - Phenomenology · Physics 2020-08-03 Dillon Berger , Seyda Ipek , Tim M. P. Tait , Michael Waterbury

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

A host of dark energy models and non-standard cosmologies predict an enhanced Hubble rate in the early Universe: perfectly viable models, which satisfy Big Bang Nucleosynthesis (BBN), cosmic microwave background and general relativity…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Schelke , R. Catena , N. Fornengo , A. Masiero , M. Pietroni

Many models possess unwanted relics, which should be diluted by entropy production just before the big-bang nucleosynthesis. A field responsible for the entropy production may produce stable weakly interacting massive particles, if…

High Energy Physics - Phenomenology · Physics 2009-10-31 Takaaki Nagano , Masahiro Yamaguchi

We investigate the relic abundance of dark matter from coannihilation in non-standard cosmological scenarios. We explore the effect of coannihilation on the relic density of dark matter and freeze out temperature in quintessence model with…

High Energy Physics - Phenomenology · Physics 2024-02-13 Fangyu Liu , Hoernisa Iminniyaz

Assuming the lightest neutralino forms dark matter, we study its residual annihilation after freeze-out at the early universe. If taking place after the big bang nucleosynthesis (BBN) the annihilation products, especially at the hadronic…

High Energy Physics - Phenomenology · Physics 2008-04-17 Xiao-Jun Bi

We discuss the relic density of the lightest of the supersymmetric particles in view of new cosmological data, which favour the concept of an accelerating Universe with a non-vanishing cosmological constant. Recent astrophysical…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. B. Lahanas , D. V. Nanopoulos , V. C. Spanos

We evaluate the relic density of the lightest neutralino, the lightest supersymmetric particle, in the Minimal Supersymmetric extension of the Standard Model (MSSM). For the first time, we include all coannihilation processes between…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Edsjo , P. Gondolo

We investigate the enhancement of neutralino relic density in the context of a realistic cosmological scenario with Quintessence. The accurate relic density computation we perform allows us to be sensitive to both cases with shifts in the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Stefano Profumo , Piero Ullio

We present brief synopses of supersymmetric models where either the neutralino composition or its mass is adjusted so that thermal relic neutralinos from the Big Bang saturate the measured abundance of cold dark matter in the universe. We…

High Energy Physics - Phenomenology · Physics 2009-01-06 Howard Baer , Azar Mustafayev , Eun-Kyung Park , Xerxes Tata

The thermal relic density of the neutralino dark matter in the brane world cosmology is studied. Since the expansion law at a high energy regime in the brane world cosmology is modified from the one in the standard cosmology, the resultant…

High Energy Physics - Phenomenology · Physics 2009-11-10 Takeshi Nihei , Nobuchika Okada , Osamu Seto

The archetypal model for the recently discovered dark energy component of the universe is based on the existence of a scalar field whose dynamical evolution comes down today to a non-vanishing cosmological constant. In the past - before…

Astrophysics · Physics 2008-11-26 Pierre Salati

Alternative cosmologies, based on extensions of General Relativity, predict modified thermal histories in the Early Universe during the pre Big Bang Nucleosynthesis (BBN) era, epoch which is not directly constrained by cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 R. Catena , N. Fornengo , M. Pato , L. Pieri , A. Masiero

In Scalar-Tensor theories of gravity, the expansion rate of the universe in the past may differ considerably from the standard one. After imposing the constraints coming from nucleosynthesis, CMB, type Ia supernovae, and solar system tests…

Astrophysics · Physics 2007-05-23 R. Catena , N. Fornengo , A. Masiero , M. Pietroni , F. Rosati

We discuss the relic density of asymmetric dark matter with long-range interactions in non-standard cosmological scenarios where the extra cosmic energy is introduced. The Hubble expansion rate is modified in non-standard cosmological…

High Energy Physics - Phenomenology · Physics 2025-06-09 Reyima Rashidin , Fangyu Liu , Hoernisa Iminniyaz
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