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Related papers: Low-scale seesaw models versus $N_{\rm eff}$

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Model-independent mass limits assess the robustness of current cosmological measurements of the neutrino mass scale. Consistency between high-multipole and low-multiple Cosmic Microwave Background observations measuring such scale further…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-12 Eleonora Di Valentino , Stefano Gariazzo , William Giarè , Olga Mena

We describe the resonance fluorescence spectrum of an atomic three-level system where two of the states are coupled by a single monochromatic laser field. The influence of the third energy level, which interacts with the two laser-coupled…

Quantum Physics · Physics 2009-11-07 Joerg Evers , Christoph H. Keitel

Sterile neutrinos are natural extensions to the standard model of particle physics in neutrino mass generation mechanisms. If they are relatively light, less than approximately 10 keV, they can alter cosmology significantly, from the early…

High Energy Physics - Phenomenology · Physics 2018-12-19 Kevork N. Abazajian

In contrast to the original type I seesaw mechanism that requires right-handed Majorana neutrinos at energies much higher than the electroweak scale, the so-called low scale seesaw models allow lighter masses for the additional neutrinos.…

High Energy Physics - Phenomenology · Physics 2020-02-11 A. E. Cárcamo Hernández , Marcela González , Nicolás A. Neill

A new and radical scenario of the simple 2006 model of radiative neutrino mass is proposed, where there is no seesaw mechanism, i.e. neutrino masses are not inversely proportional to some large mass scale, contrary to the prevalent…

High Energy Physics - Phenomenology · Physics 2015-06-05 Ernest Ma

We consider a variant of seesaw mechanism by introducing extra singlet neutrinos, with which we show how the low scale leptogenesis is realized without imposing the tiny mass splitting between two heavy Majorana neutrinos required in the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sin Kyu Kang , C. S. Kim

Radiatively generated neutrino masses ($m_\nu$) are proportional to supersymmetry (SUSY) breaking, as a result of the SUSY non-renormalisation theorem. In this work, we investigate the space of SUSY radiative seesaw models with regard to…

High Energy Physics - Phenomenology · Physics 2015-03-02 A. J. R. Figueiredo

We consider the fully constrained version of the next-to-minimal supersymmetric extension of the standard model (cNMSSM) in which a singlet Higgs superfield is added to the two doublets that are present in the minimal extension (MSSM).…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Djouadi , U. Ellwanger , A. M. Teixeira

A four-neutrino spectrum with a sterile neutrino without significant involvement in the atmospheric and solar neutrino oscillation experiments has been recently advocated as the correct picture to explain all existing experimental data. We…

High Energy Physics - Phenomenology · Physics 2009-10-31 F. Borzumati , K. Hamaguchi , T. Yanagida

The effect of statistics of the quasiparticles in the nuclear matter at extreme conditions of density and temperature is evaluated in the relativistic mean-field model generalized to the framework of the fractional exclusion statistics…

High Energy Physics - Phenomenology · Physics 2015-05-13 Dragos-Victor Anghel , A. S. Parvan , A. S. Khvorostukhin

Recent cosmological data have provided evidence for a "dark" relativistic background at high statistical significance. Parameterized in terms of the number of relativistic degrees of freedom Neff, however, the current data seems to indicate…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Maria Archidiacono , Elena Giusarma , Alessandro Melchiorri , Olga Mena

We study a regression problem where for some part of the data we observe both the label variable ($Y$) and the predictors (${\bf X}$), while for other part of the data only the predictors are given. Such a problem arises, for example, when…

Statistics Theory · Mathematics 2021-04-14 David Azriel , Lawrence D. Brown , Michael Sklar , Richard Berk , Andreas Buja , Linda Zhao

The first hint of neutrino mass hierarchy is expected to come from the NO$\nu$A experiment in Fermilab as the present best-fit parameter space i.e., normal hierarchy and $\delta_{CP}=-90^\circ$ is the favourable parameter space for NO$\nu$A…

High Energy Physics - Phenomenology · Physics 2017-12-20 Monojit Ghosh , Shivani Gupta , Zachary M. Matthews , Pankaj Sharma , Anthony G. Williams

High energy accelerators may probe into dark matter and the seesaw neutrino mass scales if they are not much heavier than ~O(TeV). In the absence of supersymmetry, we extend a class of SO(10) models to predict well known cold dark matter…

High Energy Physics - Phenomenology · Physics 2011-09-27 Mina K. Parida

We discuss a model in which three active and one sterile neutrino account for the solar, the atmospheric and the LSND neutrino anomalies. It is shown that if $N_\nu<4$ then these and other experiments and big bang nucleosynthesis constrain…

High Energy Physics - Phenomenology · Physics 2011-02-11 Nobuchika Okada , Osamu Yasuda

In this work we present Fisher forecasts on \textit{non-thermal LiMR} models for a CMB Stage IV-like experiment and the Simons Observatory -- particularly focusing on a model of inflaton/moduli decay giving rise to non-thermally distributed…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-10 Arka Banerjee , Abhik Bhattacharjee , Subinoy Das , Anshuman Maharana , Ravi Kumar Sharma

Recently, two measures of electroweak finetuning (EWFT) have been introduced for SUSY models: \Delta_{EW} compares the Z mass to each separate weak scale contribution to m_Z while \Delta_{HS} compares the Z mass to high scale input…

High Energy Physics - Phenomenology · Physics 2013-10-30 Howard Baer , Vernon Barger , Maren Padeffke-Kirkland

Recent Cosmic Microwave Background (CMB) results from the Planck satellite, combined with previous CMB data and Hubble constant measurements from the Hubble Space Telescope, provide a constraint on the effective number of relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Eleonora Di Valentino , Alessandro Melchiorri , Olga Mena

It has been suggested that both recent cosmological data and the results of flavor oscillation experiments (MiniBooNE and LSND) lend support to the existence of low-mass sterile neutrinos. The cosmological data appear to weakly favor…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-29 Alma X. Gonzalez-Morales , Robert Poltis , Blake D. Sherwin , Licia Verde

The acoustic peaks in the angular power spectrum of cosmic microwave background (CMB) temperature and polarization anisotropies play an important role as a probe of the nature of new relativistic particles contributing to the radiation…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-03 Gongjun Choi , Chi-Ting Chiang , Marilena LoVerde