English
Related papers

Related papers: Fermion mass effects in e+e- --> 4f and e+e- --> 4…

200 papers

We analyse the contribution of new heavy virtual fermions to the $e^+e^- \rightarrow W^+W^-$ cross section. We find that there exists a relevant interplay between trilinear and bilinear oblique corrections. The result strongly depends on…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Culatti , G. Degrassi , F. Feruglio , A. Masiero , S. Rigolin , L. Silvestrini , A. Vicini

Modification of the particles in the course of the source evolution is considered. Influence of this effect on multiplicities and correlations of the particles is displayed, including an enhancement of the production rates and identical…

High Energy Physics - Phenomenology · Physics 2007-05-23 I. V. Andreev

The effect of a fermion with angular momentum j on quantum phase transitions of a (s,d) bosonic system is investigated. It is shown that the presence of a fermion strongly modifies the critical value at which the transition occurs, and its…

Nuclear Theory · Physics 2013-04-16 F. Iachello , A. Leviatan , D. Petrellis

We present a study of the effective action approach to incorporate higher-order effects in e^+e^- -> n fermions. In its minimal version, the effective action approach is found to exhibit problems with unitarity and high-energy behaviour. We…

High Energy Physics - Phenomenology · Physics 2009-11-10 W. Beenakker , A. P. Chapovsky , A. Kanaki , C. G. Papadopoulos , R. Pittau

This paper studies the electroweak production of all possible four-fermion states in $e^+e^-$ collisions with non-standard triple gauge boson couplings. All $CP$ conserving couplings are considered. It is an extension of the methods and…

High Energy Physics - Phenomenology · Physics 2008-11-26 F. A. Berends , A. I. van Sighem

Isospin e ffects on multifragmentation properties were studied thanks to nuclear collisions between di fferent isotopes of xenon beams and tin targets. It is shown that, in central collisions leading to multifragmentation, the mean number…

We argue that all fermionic states characterized by the (four) velocity not momentum of the fermion are always occupied by a single fermion. So there is no fermion number violation whatsoever. The mass of an elementary particle is not…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jyoti Sekhar Bhattacharyya

We review some recent work on nonperturbative properties of fermions and connections with chiral gauge theories. In particular, we consider one of the ultimate goals of this program: the understanding of the actual fermion mass spectrum. It…

High Energy Physics - Phenomenology · Physics 2009-10-22 R. Shrock

We study the localization of fermions on a brane embedded in a space-time with $AdS_n \times M^k$ geometry. Quantum numbers of localized fermions are associated with their rotation momenta around the brane. Fermions with different quantum…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Andrey Neronov

A precise simulation of muons with energies above a TeV is crucial for neutrino telescopes or cosmic ray experiments. To further increase the precision of these simulations, improved cross-section calculations are needed. At these energies,…

High Energy Physics - Phenomenology · Physics 2019-10-17 Jan Soedingrekso , Alexander Sandrock , Wolfgang Rhode

Many-body effects may influence properties, such as scattering parameters, nature of pairing, etc., close to a Feshbach resonance in the fermion BEC-BCS crossover problem. We study effects such as these using a tractable crossing-symmetric…

Quantum Gases · Physics 2015-06-05 Renyuan Liao , Khandker F. Quader

Electroweak processes with four fermions in the final state were measured extensively at LEP-2 in e+e- collisions with centre-of-mass energies up to 209 GeV. By combining the results obtained by Aleph, Delphi, L3 and Opal, the predictions…

High Energy Physics - Experiment · Physics 2007-05-23 Philip Bambade

Using the recently proposed ALPHA algorithm (and the resulting code) I compute the rate (at tree level) for the process $\gamma\gamma\rightarrow\bar\nu_e e^- u \bar d$. The bulk of the contribution is due to W pair production and decay.…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Moretti

Future high-energy $e^+e^-$ colliders will provide some of the most precise tests of the Standard Model. Statistical uncertainties on electroweak precision observables and triple gauge couplings are expected to improve by orders of…

High Energy Physics - Experiment · Physics 2021-11-15 Jakob Beyer , Jenny List

It is known that the charged lepton masses obey to high precision an interesting empirical relation (Koide relation). In turn, the light neutrino masses cannot obey such a relation. We note that if neutrinos acquire their mass via the…

High Energy Physics - Phenomenology · Physics 2011-07-26 Werner Rodejohann , He Zhang

For lattice calculations with light dynamical quarks, finite size effects have become an important aspect. We study finite size effects in nucleon masses on N_f=2 dynamical lattices of 1-2 fm. Predictions for the finite size effects are…

High Energy Physics - Lattice · Physics 2008-11-26 A. Ali Khan , T. Bakeyev , M. Göckeler , R. Horsley , A. C. Irving , D. Pleiter , P. Rakow , G. Schierholz , H. Stüben

We study the Gross-Neveu model in 2+1 dimensions with a baryon chemical potential mu using both analytical and numerical methods. For mu greater than a critical value the model is chirally symmetric and has a Fermi surface with Fermi…

High Energy Physics - Lattice · Physics 2009-11-10 Simon Hands , John B. Kogut , Costas G. Strouthos , Thao N. Tran

We calculate the parametrically dominant next-to-next-to-leading order corrections to four-fermion production e^- e^+ -> mu^- nubar_mu u dbar + X at centre-of-mass energies near the W-pair production threshold employing the method of…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Actis , M. Beneke , P. Falgari , C. Schwinn

The problem of a few interacting fermions in quantum physics has sparked intense interest, particularly in recent years owing to connections with the behavior of superconductors, fermionic superfluids, and finite nuclei. This review…

Atomic Physics · Physics 2015-05-20 Seth T. Rittenhouse , J. von Stecher , J. P. D'Incao , N. P. Mehta , Chris H. Greene

The effective action of (2+1)-dimensional QED with finite fermion density is calculated in a uniform electromagnetic field. It is shown that the integer quantum Hall effect and de Haas-van Alphen like phenomena in condensed matter physics…

High Energy Physics - Theory · Physics 2009-10-30 Dae Kwan Kim , Kwang-Sup Soh