arXiv subjects

Stephen Parke

Publications and source records attributed to Stephen Parke.

44 records · Page 3Linked to original sources

arXiv1995

Angular Correlations in Top Quark Pair Production and Decay at Hadron Colliders

We show how to observe sizable angular correlations between the decay products of the top quark and those of the anti-top quark in top quark pair production and decay at hadron colliders. These correlations result from the large asymmetry in the rate for producing like-spin versus unlike-spin top quark pairs provided the appropriate spin axes are used. The effects of new physics at production or decay on these correlations are briefly discussed.

hep-ph↗

arXiv1995

Top Quark Pair Production: Sensitivity to New Physics

The production cross--section and distributions of the top quark are sensitive to new physics, e.g., the $t\overline{t}$ system can be a probe of new resonances or gauge bosons that are strongly coupled to the top quark, in analogy to Drell--Yan production. The existence of such new physics is expected in dynamical electroweak symmetry breaking schemes, and associated with the large mass of the top quark. The total top production cross--section can be more than doubled, and distributions significantly distorted with a chosen scale of new physics of $\sim 1 $ TeV in the vector color singlet or octet $s$--channel. New resonance physics is most readily discernible in the high--$p_T$ distributions of the single top quark, of the $W$ boson and the mass distribution of the $t\bar{t}$ pair.

hep-ph↗

arXiv1995

The Solar Neutrino Puzzle: Update

In this talk I will summarize the latest experimental results from the four solar neutrino experiments and discuss what this means for the flux of $^7Be$ and $^8B$ neutrinos. The implications for the solar models including the new versions with helium and heavy element diffusion will also be addressed. The exciting and important calibration results of the Gallex collaboration will be presented as well as the outlook for the next generation of solar neutrino experiments.

hep-ph↗

arXiv1995

Top Quark Production Dynamics

I review standard top quark production at the Fermilab Tevatron. The current theoretical understanding of the total cross section and many partial differential cross sections is presented. Studies on the effects of extra gluon radiation on the top quark mass determination are reviewed. The possibility of new mechanisms for $t\bar{t}$ production are also discussed.

hep-ph↗

arXiv1994

Status of the Solar Neutrino Puzzle

Using the latest results from the solar neutrino experiments and a few standard assumptions, I show that the popular solar models are ruled out at the 3$σ$ level or at least TWO of the experiments are incorrect. Alternatively, one of the assumptions could be in error. These assumptions are spelled out in detail as well as how each one affects the argument.

hep-ph↗

arXiv1994

Summary of Top Quark Physics

I briefly review standard top quark physics at hadron colliders and summarize the contributions to this conference. The possibility of new mechanisms for $t\bar{t}$ production are also discussed.

hep-ph↗

arXiv1993

Heavy Top Quark Searches in the Di-Lepton Mode at the Tevatron

We present the results of a detailed study of the effects of $b$-tagging on the heavy top-quark signal and backgrounds for the modes of the di-lepton plus two high transverse energy jets at the Fermilab Tevatron. The general characteristics of the heavy top-quark signal events are also discussed so that a comparison can be made between $b$-tagging and imposing stringent kinematical cuts to eliminate backgrounds.

hep-ph↗

arXiv1993

Overview of Accelerator Long Baseline Neutrino Oscillation Experiments

There is renewed interest in performing a long baseline neutrino oscillation experiment using accelerator neutrinos because of a discrepancy between the measured and the predicted values of the ratio of electron to muon neutrinos produced in the upper atmosphere by cosmic rays.The approximate range in oscillation parameter space indicated by the Kamiokande atmospheric neutrino results and confirmed by IMB is bounded by $ 10^{-3}~ eV^2 < \dmsq < 10^{-1}~ eV^2 $ and $\s2t > 0.4~$. To reach such small $\dmsq$, using an accelerator as the source of neutrinos where the energy is typically 1 GeV or greater, requires baselines in the range of 10~km to 1000~km. In this talk I will give an overview of the most likely possibilities for such a long baseline accelerator neutrino oscillation experiment.

hep-ph↗