Top quark production and decay at next-to-leading order in e+e- annihilation.
نویسنده
چکیده
We study the effects of QCD corrections to the process ee → tt̄ + X → blνb̄lν̄ + X above threshold. We show how to treat consistently to O(αs) the gluon radiation in both the production and the decay of the top quarks, while maintaining all angular correlations in the event. At this order there is an ambiguity in the event reconstruction whenever a real gluon occurs in the final state. We study the effects of this ambiguity on the top mass and helicity angle distributions. For a top mass of 175 GeV and collider energy of 400 GeV the gluon radiation is emitted predominantly in the decay of the top quarks. Supported in part by the U.S. Department of Energy.
منابع مشابه
Renormalization-group improved calculation of top-quark production near threshold.
The top-quark cross section close to threshold in e(+)e(-) annihilation is computed including the summation of logarithms of the velocity at next-to-next-to-leading-logarithmic order in QCD. The remaining theoretical uncertainty in the normalization of the total cross section is at the few-percent level, an order of magnitude smaller than in previous next-to-next-to-leading order calculations. ...
متن کاملAnalytical results for e + e − → tt̄ and γγ → tt̄ observables near the threshold up to the next - to - next - to - leading order of NRQCD
+ e − → t ¯ t and γγ → t ¯ t observables near the threshold up to the next-to-next-to-leading order of NRQCD. Abstract We present the analytical description of top-antitop pair production near the threshold in e + e − annihilation and γγ collisions. A set of basic observables considered includes the total cross sections, forward-backward asymmetry and top quark polarization. The threshold effec...
متن کامل→ tt̄ and γγ → tt̄ observables near the threshold up to the next - to - next - to - leading order of NRQCD
+ e − → t ¯ t and γγ → t ¯ t observables near the threshold up to the next-to-next-to-leading order of NRQCD. Abstract We present an analytical description of top-antitop pair production near the threshold in e + e − annihilation and γγ collisions. A set of basic observables considered includes the total cross sections, forward-backward asymmetry and top quark polarization. The threshold effect...
متن کاملNext-to-Next-to-Next-to-Leading Order QCD Prediction for the Top Antitop S-Wave Pair Production Cross Section Near Threshold in e(+)e(-) Annihilation.
We present the third-order QCD prediction for the production of top antitop quark pairs in electron-positron collisions close to the threshold in the dominant S-wave state. We observe a significant reduction of the theoretical uncertainty and discuss the sensitivity to the top quark mass and width.
متن کاملThree-loop O( 2 S G F M 2 T ) Corrections to Higgs Production and Decay at E + E ? Colliders
We evaluate the next-to-leading-order QCD corrections of O(2 s G F M 2 t) to the Standard-Modeì + ` ? H, ZZH, and W + W ? H couplings in the heavy-top-quark limit. Exploiting these results together with knowledge of to the same order, we analyze a variety of production and decay processes of low-mass Higgs bosons at fH, with f = `;. We work in the electroweak on-shell scheme formulated with G F...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Physical review. D, Particles and fields
دوره 54 5 شماره
صفحات -
تاریخ انتشار 1996