Search results for "SCALAR"
showing 10 items of 1002 documents
An ultraviolet completion for the Scotogenic model
2021
The Scotogenic model is an economical scenario that generates neutrino masses at the 1-loop level and includes a dark matter candidate. This is achieved by means of an ad-hoc $\mathbb{Z}_2$ symmetry, which forbids the tree-level generation of neutrino masses and stabilizes the lightest $\mathbb{Z}_2$-odd state. Neutrino masses are also suppressed by a quartic coupling, usually denoted by $\lambda_5$. While the smallness of this parameter is natural, it is not explained in the context of the Scotogenic model. We construct an ultraviolet completion of the Scotogenic model that provides a natural explanation for the smallness of the $\lambda_5$ parameter and induces the $\mathbb{Z}_2$ parity a…
The scalar form factor in the exclusive semi-leptonic decay of B→π+τ+ντ
1990
Abstract Using current algebra and the soft pion theory we derive the Callan-Treiman type relation ƒ(t max )≅ ƒ B ƒ π for the scalar form factor in the exclusive semi-leptonic decay B→π+τ+ντ.
Majoron effects in rare kaon decays
1989
Abstract We analyze, in the framework of the recently introduced doublet majoron model, the contribution from the emission of a pair of light scalars to the decay K + → π + + nothing . We find that, for reasonable choices of the parameters, the new scalar contribution may be as large as one additional neutrino-antineutrino mode and provide a substantial modification of the pion spectrum. The effect may be a few times larger in the triplet majoron model.
Radiative decay of the dynamically generated open and hidden charm scalar meson resonancesDs0*(2317)andX(3700)
2007
We present the formalism for the decay of dynamically generated scalar mesons with open- or hidden charm and give results for the decay of ${D}_{s0}^{*}(2317)$ to $\ensuremath{\gamma}{D}_{s}^{*}$ plus that of a hidden charm scalar meson state predicted by the theory around 3700 MeV decaying into $\ensuremath{\gamma}J/\ensuremath{\psi}$.
A precise measurement of the muon neutrino nucleon inclusive charged current cross section off an isoscalar target in the energy range 2.5
2008
Abstract We present a measurement of the muon neutrino–nucleon inclusive charged current cross section, off an isoscalar target, in the neutrino energy range 2.5 ⩽ E ν ⩽ 40 GeV . The significance of this measurement is its precision, ±4% in 2.5 ⩽ E ν ⩽ 10 GeV , and ±2.6% in 10 ⩽ E ν ⩽ 40 GeV regions, where significant uncertainties in previous experiments still exist, and its importance to the current and proposed long baseline neutrino oscillation experiments.
Two pion mediated scalar isoscalarNNinteraction in the nuclear medium
2005
We study the modification of the nucleon nucleon interaction in a nuclear medium in the scalar isoscalar channel, mediated by the exchange of two correlated ($\sigma$ channel) or uncorrelated pions. For this purpose we use a standard approach for the renormalization of pions in nuclei. The corrections obtained for the $NN$ interaction in the medium in this channel are of the order of 20% of the free one in average, and the consideration of short range correlations plays an important role in providing these moderate changes. Yet, the corrections are sizable enough to suggest further studies of the stability and properties of nuclear matter.
Chiral unitary dynamics of hadrons and hadrons in a nuclear medium
2009
4th DAE-BRNS Workshop on Hadron Physics. Aligarh Muslim Univ, Dept Phys, Aligarh, INDIA, FEB 18-23, 2008
On the classification of accidental symmetries of the two Higgs doublet model potential
2011
Recently, it has been shown [arXiv:1106.3482] that the two-Higgs-doublet-model potential may exhibit a maximum of 13 distinct accidental symmetries. Such a classification is based on a six-dimensional bilinear scalar field formalism realizing the SO(1,5) symmetry group. This note presents the transformation relations for each of the 13 symmetries in the original scalar field space and their one-to-one correspondence to the space of scalar bilinears, thereby providing firm support for the completeness of the classification.
Unstable massive tau-neutrinos and primordial nucleosynthesis
1998
The impact of unstable Majorana tau neutrinos on primordial nucleosynthesis is considered. The mass and lifetime of nu_tau are taken in the intervals 0.1-20 MeV and 0.001-400 sec respectively. The studied decay modes are nu_tau -> nu_mu + phi and nu_tau -> nu_e + phi, where phi is a massless (or light) scalar. Integro-differential kinetic equations are solved numerically without any simplifying assumptions. Our results deviate rather strongly from earlier calculations. Depending on mass, lifetime, and decay channels of the nu_tau, the number of effective neutrino species (found from He4), in addition to the 3 standard ones, varies from -2 to +2.5. The abundances of H2 and Li7 are also…
The radiative decay of $\psi(3770)$ into the predicted scalar state X(3700)
2009
5 pages, 1 figure.-- ISI article identifier:000267299600009.-- ArXiv pre-print avaible at:http://arxiv.org/abs/0805.0499