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Interactions in an ultracold boson-fermion mixture are often manifested by elastic collisions. In a mixture of a condensed Bose gas (BEC) and spin polarized degenerate Fermi gas (DFG), fermions can mediate spin-spin interactions between…

Atomic Physics · Physics 2020-05-12 Hagai Edri , Boaz Raz , Noam Matzliah , Nir Davidson , Roee Ozeri

We study the effects of non-commutative QED (NCQED) in fermion pair production, gamma + gamma to f + \bar{f} and Compton scattering, e + gamma to e + gamma. Non-commutative geometries give rise to 3- and 4-point photon vertices and to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stephen Godfrey , M. A. Doncheski

We review recent progress in calculating kaon spectrum, pseudoscalar meson decay constants, $B_K$, $\epsilon'/\epsilon$, $K\to \pi\pi$ matrix elements, kaon semileptonic form factors, and moments of kaon distribution amplitudes on the…

High Energy Physics - Lattice · Physics 2008-11-26 Weonjong Lee

We show that the decays with pressure of the alignment echoes induced in N2O-He gas mixtures by two laser pulses with various delays bring detailed information on collision-induced changes of the rotational speed. Measurements and…

The cross sections for several $\gamma \gamma \to VV$ processes exhibit strong enhancements near threshold, where $V$ denotes a vector meson. The pattern of these enhancements is not well understood; for example, $\gamma \gamma \to \rho^0…

High Energy Physics - Phenomenology · Physics 2009-11-10 Jonathan L. Rosner

Production of lepton pairs in gamma p -> e-e+ p reaction is studied at photon energies up to 1 GeV. We show that even if lepton charge is not measured there are extensive kinematical regimes where the nuclear process dominates over the…

Nuclear Theory · Physics 2009-11-06 A. Yu. Korchin , O. Scholten

We perform exact calculations of collisional frequency shifts for several fermions or bosons using a singlet and triplet basis for pairs of particles. The "factor of 2 controversy" for bosons becomes clear - the factor is always 2.…

Atomic Physics · Physics 2009-09-14 Kurt Gibble

We estimate the numbers and mass spectra of observed lepton and kaon pairs produced from $\phi$ meson decays in the central rapidity region of an Au+Au collision at lab energy 11.6 GeV/nucleon. The following effects are considered: possible…

Nuclear Theory · Physics 2009-09-25 David Seibert , Charles Gale

In a model with a gauge group $G_{SM}\otimes U(1)_X$, where $G_{SM} \equiv SU(3)_C \otimes SU(2)_L \otimes U(1)_Y$ is the standard model gauge group and $U(1)_X$ is a horizontal local gauge symmetry, the spectrum of charged fermion masses…

High Energy Physics - Phenomenology · Physics 2016-09-06 E. Garcia-Reyes , A. Hernandez-Galeana , A. Vargas , A. Zepeda

The boson and fermion particle masses are calculated in a finite quantum field theory. The field theory satisfies Poincar\'e invariance, unitarity and microscopic causality, and all loop graphs are finite to all orders of perturbation…

High Energy Physics - Phenomenology · Physics 2021-06-01 J. W. Moffat

The Fermion flavor structure is investigated by bilinear decomposition of the mass matrix after EW symmetry breaking, and the roles of factorized matrices in flavor mixing and mass generation are explored. It is shown that flavor mixing can…

High Energy Physics - Phenomenology · Physics 2023-09-12 Guojun Xu , Jingjun Zhang , Chenzi Liao , Ying Zhang

Flavor symmetries that explain masses and mixings of the standard model fermions dictate flavor patterns for the couplings of scalar and vector leptoquarks to the standard model fermions. A generic feature is that couplings to…

High Energy Physics - Phenomenology · Physics 2017-01-04 Gudrun Hiller , Dennis Loose , Kay Schönwald

The medium modification of vector meson masses is studied taking into account the quantum correction effects for the hot and dense hadronic matter. In the framework of Quantum Hadrodynamics, the quantum corrections from the baryon and…

Nuclear Theory · Physics 2008-11-26 Amruta Mishra , Jitendra C. Parikh , Walter Greiner

An analysis is given of the decay $\mu \to e+ \gamma$ in an MSSM extension with a vectorlike generation. Here mixing with the mirrors allows the possibility of this decay. The analysis is done at the one loop level with the exchange of…

High Energy Physics - Phenomenology · Physics 2015-06-26 Tarek Ibrahim , Ahmad Itani , Pran Nath

We review simulations of dynamical domain wall fermions at a fixed inverse lattice spacing of 1.73GeV and with pion masses as light as 330MeV and spatial dimensions as large as 2.7fm performed by the RBC and UKQCD collaborations. These…

High Energy Physics - Lattice · Physics 2009-07-30 Peter Boyle , RBC , UKQCD Collaborations

We propose a framework that links the origin of the Standard Model flavour hierarchies to the generation of asymmetric dark matter via leptogenesis. The key new ingredient is a gauged $SO(3)$ flavour symmetry acting on both the visible and…

High Energy Physics - Phenomenology · Physics 2026-05-21 Mattias Blennow , Enrique Fernandez-Martinez , David Garcia-Garcia , Javier M. Lizana

In this talk I describe work on computing non-leptonic matrix elements consistently with both long and short distance contributions included. On the simpler example of the $\pi^+$-$\pi^0$ mass difference I explain in detail the matching…

High Energy Physics - Phenomenology · Physics 2009-10-31 Johan Bijnens

We formulate a predictive model of fermion masses and mixings based on a $\Delta(27)$ family symmetry. In the quark sector the model leads to the viable mixing inspired texture where the Cabibbo angle comes from the down quark sector and…

High Energy Physics - Phenomenology · Physics 2018-06-13 Nicolás Bernal , A. E. Cárcamo Hernández , Ivo de Medeiros Varzielas , Sergey Kovalenko

We study the lepton-flavor-violating reaction $\mu^+ e^- \to e^+ e^-$ within two extensions of the standard model that include heavy neutrinos. The reaction is studied in the low energy limit in the form of muonium decay $M\to e^+ e^-$ and…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gorazd Cvetic , Claudio O. Dib , Choong-Sun Kim , JungDae Kim

We consider a flavor model based on A4 modular group to account for both lepton and quark parameters (masses and mixing). The inverse seesaw mechanism is considered to produce the light neutrino masses. Lepton masses and mixing are obtained…

High Energy Physics - Phenomenology · Physics 2021-03-31 Mohamed Abbas
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