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相关论文: Light Fermion Mass Effects in e^+e^- -> 4 Fermions

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The cross section for different processes induced by $e^+e^-$ annihilation, in the kinematical limit $\beta_{\mu}\approx\beta_{\pi}=(1-m_{\pi}^2/\epsilon^2)^{1/2}\sim 1$, is calculated taking into account first order corrections to the…

高能物理 - 唯象学 · 物理学 2008-12-25 E. A. Kuraev , A. I. Ahmadov , S. N. Panov , E. Tomasi-Gustafsson

We review the precision measurement of the mass of the W-boson at LEP. We discuss the techniques used by the four LEP experiments to determine the mass of the W-boson as well as the major sources of systematic uncertainty. The measurement…

高能物理 - 实验 · 物理学 2007-05-23 Raimund Ströhmer

Meson and baryon masses in the light (u,d and s) sector are calculated using tadpole-improved gauge field and fermion actions. These are corrected to order $O(a^2)$ on the classical level using next-nearest-neighbour terms. The results,…

高能物理 - 格点 · 物理学 2009-10-28 H. R. Fiebig , R. M. Woloshyn

We present a general classification of all four fermion final states in $\gamma\gamma$~collisions and a calculation of cross sections below the $W^+W^-$-threshold.

高能物理 - 唯象学 · 物理学 2007-05-23 Edward Boos , Thorsten Ohl

We make several observations concerning the low quark mass region with Wilson fermions and how this is connected with the epsilon regime in the continuum. A transition from tiny cutoff effects to rather large discretization errors would…

高能物理 - 格点 · 物理学 2009-02-27 Andrea Shindler

The effect of the photon emission (bremsstrahlung) in the cross section of the process of direct production of the Higgs boson in the future high luminosity electron and muon colliders is calculated. It was found that cross section at the…

高能物理 - 唯象学 · 物理学 2016-02-10 S. Jadach , R. A. Kycia

We study fermion mass correction to chiral kinetic equations in electromagnetic fields. Different from the chiral limit where fermion number density is the only independent distribution, the number and spin densities are coupled to each…

高能物理 - 唯象学 · 物理学 2021-02-03 Ziyue Wang , Xingyu Guo , Shuzhe Shi , Pengfei Zhuang

We study fermion mass correction to chiral kinetic equations in electromagnetic fields. Different from the chiral limit where fermion number density is the only independent distribution, the number and spin densities are coupled to each…

高能物理 - 唯象学 · 物理学 2019-07-24 Ziyue Wang , Xingyu Guo , Shuzhe Shi , Pengfei Zhuang

Electroweak precision observables allow stringent tests of the Standard Model at the quantum level and imply interesting bounds on the mass of the Higgs boson through higher-order loop effects. Very significant constraints come especially…

高能物理 - 唯象学 · 物理学 2008-11-26 A. Freitas , M. Awramik , M. Czakon

The rate for the production of a pair of massive fermions in $e^+ e^-$ annihilation plus real or virtual radiation of a pair of massless fermions is calculated analytically. The contributions for real and virtual radiation are displayed…

高能物理 - 唯象学 · 物理学 2009-10-28 A. H. Hoang , J. H. Kühn , T. Teubner

We study the interaction between photons, dark photons, and axions at future lepton colliders, focusing on single-photon events with missing energy as the experimental signature. We find that future facilities such as the ILC, CEPC, and…

高能物理 - 唯象学 · 物理学 2025-09-11 Chuan-Ren Chen , Yuan-Feng Hsieh , Van Que Tran

The $W$-boson mass ($m_{W}=80.4335 \pm 0.0094 \mathrm{GeV}$) measured by the Collider Detector at Fermilab collaboration is greater than the standard model (SM) prediction at a confidence level of $7\sigma$, strongly suggesting the presence…

高能物理 - 唯象学 · 物理学 2023-02-22 Guan-Wen Yuan , Lei Zu , Lei Feng , Yi-Fu Cai , Yi-Zhong Fan

Precise measurements of the mass and width of the W boson are carried out in e+e- collisions at LEP, by kinematic reconstruction of the invariant mass distributions of WW->qqlv and WW->qqqq candidate events. The most recent combination of…

高能物理 - 唯象学 · 物理学 2016-09-06 Nigel K. Watson

Model estimates are obtained for the influence of Coulomb effects on the ratio of the cross sections for the production of charged and neutral $B\bar B$ and $B^*\bar B^*$ pairs in $e^+e^-$ annihilation. It is shown that the difference…

高能物理 - 唯象学 · 物理学 2022-10-11 A. E. Bondar , A. I. Milstein , R. V. Mizuk , S. G. Salnikov

Numerical data of the SU(3) gauge theory with $N_f=8$ fermions in the fundamental representation suggest the existence of a large-mass regime, where the fermion mass is not small relative to the confinement scale, but nevertheless the…

高能物理 - 唯象学 · 物理学 2018-10-03 Maarten Golterman , Yigal Shamir

We determine the light baryon spectrum on ensembles generated by the Coordinated Lattice Simulations (CLS) effort, employing $N_f=2+1$ flavours of non-perturbatively improved Wilson fermions. The hadron masses are interpolated and…

The first part of the physics programme of the integrated FCC (Future Circular Colliders) proposal includes measurements of Standard Model processes in $e^+e^-$ collisions (FCC-ee) with an unprecedented precision. In particular, the…

高能物理 - 实验 · 物理学 2019-10-31 Georgios Voutsinas , Emmanuel Perez , Mogens Dam , Patrick Janot

The past ten years of physics with e+e- colliding experiments at LEP and SLAC have shown the success of these experiments on not only impressively proving the theoretical predictions of the Standard Model (SM), but also to help provide…

高能物理 - 唯象学 · 物理学 2007-05-23 P. Christova , M. Jack , S. Riemann , T. Riemann

We generalize the inclusion of the imaginary parts of the fermionic one-loop corrections for processes with unstable vector bosons to the case of massive external fermions and non conservation of weak currents. We study the effect of…

高能物理 - 唯象学 · 物理学 2016-09-06 Elena Accomando , Alessandro Ballestrero , Ezio Maina

The observed cross sections for $e^+e^-\rightarrow \mu^+\mu^-$ at energies from 3.8 to 4.6 GeV are measured using data samples taken with the BESIII detector operated at the BEPCII collider. We measure the muonic widths and determine the…

高能物理 - 实验 · 物理学 2021-01-04 BESIII Collaboration