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Related papers: Leptonic Photons and Nucleosynthesis

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The LFV charged lepton decays mu to e + gamma, tau to e + gamma and tau to mu + gamma and thermal leptogenesis are analysed in the MSSM with see-saw mechanism of neutrino mass generation and soft SUSY breaking with universal boundary…

High Energy Physics - Phenomenology · Physics 2010-04-05 S. T. Petcov , W. Rodejohann , T. Shindou , Y. Takanishi

In the relatively recent CMS data, there is a hint on the existence of a resonance with the mass 28 GeV coupling to muons. Such a resonance should also couple to photons through the fermion loop, therefore it can be searched for in…

High Energy Physics - Phenomenology · Physics 2021-02-24 S. I. Godunov , E. K. Karkaryan , V. A. Novikov , A. N. Rozanov , M. I. Vysotsky , E. V. Zhemchugov

We elucidate the physical basis for the upper bound on high energy neutrino fluxes implied by the observed cosmic ray flux. We stress that the bound is valid for neutrinos produced either by p,gamma reactions or by p-p(n) reactions in…

High Energy Physics - Phenomenology · Physics 2011-04-20 John Bahcall , Eli Waxman

We compute the big bang nucleosynthesis limit on the number of light neutrino degrees of freedom in a model-independent likelihood analysis based on the abundances of He4 and Li7. We use the two-dimensional likelihood functions to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith A. Olive , David Thomas

We summarize recent works on the question of the nucleon mass decomposition and the 2D relativistic distribution of pressure forces on the light front. All these mechanical properties are encoded in the energy-momentum tensor of the system…

High Energy Physics - Phenomenology · Physics 2019-10-15 Cédric Lorcé

A computation of nucleosynthesis bounds on the masses of long-lived Dirac and Majorana neutrinos is reviewed. In particular an explicit treatment of the ``differential heating'' of the $\nue$ and $\bnue$ ensembles due to the residual…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kimmo Kainulainen

We investigate the dipole moments of the tau- neutrino at high-energy and high luminosity at linear electron positron colliders, such as CLIC or ILC through the analysis of the reaction $e^{+}\, e^{-}\rightarrow \nu\, \bar \nu \,\gamma$ in…

High Energy Physics - Phenomenology · Physics 2019-05-15 D. T. Binh , Vo Van On , H. N. Long

The upper bound on the number of relativistic species present at nucleosynthesis has been used to constrain particles with electric charge $\epsilon e$ ($10^{-8} < \epsilon <1$). We correct the bound previously calculated for milli-charged…

High Energy Physics - Phenomenology · Physics 2009-10-22 Sacha Davidson , Michael Peskin

Various precision determinations of the Fermi constant are compared. Included are muon and (leptonic) tau decays as well as indirect prescriptions employing $\alpha, m_Z, m_W, \ssthwmzms, \Gamma(Z\to\ell^+\ell^-)$, and $\Gamma(Z \to \nu\bar…

High Energy Physics - Phenomenology · Physics 2008-11-26 William J. Marciano

The energy levels of the muonium ($\mu^+ e^-$) atom, which consists of two ''point-like'' leptonic particles, can be calculated to very high accuracy in the framework of bound state Quantum Electrodynamics (QED), since there are no…

Atomic Physics · Physics 2016-09-08 Klaus P. Jungmann

A nonconventional $U(1)_{e-\mu}$ gauge model is proposed to explain the unexpected anomalous magnetic moments of the electron and muon (lepton $g-2$), where only the right-handed electron and muon in the standard model carry the…

High Energy Physics - Phenomenology · Physics 2021-02-24 Chuan-Hung Chen , Takaaki Nomura

The neutrino-nucleon cross section is slightly larger than that for $\bar\nu-N$. Therefore, $\bar\nu$ will escape more quickly from core collapse supernovae leaving the star $\nu$ rich. A diffusion formalism is used to calculate the time…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. J. Horowitz , Gang Li

We compute the photon spectrum and the rate for the decays $B(D)\to l\nu_l\gamma$ These photonic modes constitute a potentially large background for the purely leptonic decays which are used to extract the heavy meson decay constants. While…

High Energy Physics - Phenomenology · Physics 2009-09-25 G. Burdman , T. Goldman , D. Wyler

The progress of Particle Physics is closely linked to the progress in the understanding of the fundamental constants, like the finestructure constant, the mass of the electron or nucleon, or the electroweak mixing angle. The relation…

High Energy Physics - Phenomenology · Physics 2015-06-25 H. Fritzsch

Using data collected with the L3 detector near the Z resonance, corresponding to an integrated luminosity of 150pb-1, the branching fractions of the tau lepton into electron and muon are measured to be B(tau->e nu nu) = (17.806 +- 0.104…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

The lepton-number violating process e p \to nu_e l l' X mediated by Majorana neutrinos is studied for the HERA collider for (l l') = (e tau), (mu tau), (mu mu) and (tau tau). Only the muonic decay of the tau is considered. The direct limit…

High Energy Physics - Phenomenology · Physics 2011-07-19 Marion Flanz , Werner Rodejohann , Kai Zuber

Using 4.68 fb^{-1} of e^+e^- annihilation data collected with the CLEO II detector we have studied tau radiative decays tau --> mu nu nu gamma and tau --> e nu nu gamma. For a 10 MeV minimum photon energy in the tau rest frame, the…

High Energy Physics - Experiment · Physics 2007-05-23 T. Bergfeld , CLEO Collaboration

The hydrogen-like muonium atom ($\mu^+e^-$) consists of a positive muon ($\mu^+$) and an electron ($e^-$). Since it was first observed by Hughes et al. in 1960, a series of precision experiments could be carried out testing bound state…

Atomic Physics · Physics 2016-09-08 K. Jungmann

Using Big Bang Nucleosynthesis limits on the number of light neutrinos we derive a cosmological lower bound of $\approx 2$ TeV on the scale of extended technicolor interactions (or any other new interactions) for the third family in models…

High Energy Physics - Phenomenology · Physics 2009-10-22 Lawrence M. Krauss , John Terning , Thomas Appelquist

We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on He4 and Li7 to allow for numbers of degrees of freedom which differ from the standard model value characterized by $N_\nu = 3$. We use the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith A. Olive , David Thomas