Searcharxiv⌕ Search

arXiv subjects

M. L. Mangano

Publications and source records attributed to M. L. Mangano.

67 records · Page 4Linked to original sources
arXiv1996

The Resummation of Soft Gluon in Hadronic Collisions

We compute the effects of soft gluon resummation for the production of high mass systems in hadronic collisions. We carefully analyse the growth of the perturbative expansion coefficients of the resummation formula. We propose an expression consistent with the known leading and next-to-leading resummation results, in which the coefficients grow much less than factorially. We apply our formula to Drell--Yan pair production, heavy flavour production, and the production of high invariant mass jet pairs in hadronic collisions. We find that, with our formula, resummation effects become important only fairly close to the threshold region. In the case of heavy flavour production we find that resummation effects are small in the experimental configurations of practical interest.

hep-ph↗
arXiv1996

Heavy-quark jets in hadronic collisions

We present a next-to-leading order QCD calculation of the production rates of jets containing heavy quarks. This calculation is performed using the standard Snowmass jet algorithm; it therefore allows a comparison with similar results known at next-to-leading order for generic jets. As an application, we present results for the inclusive transverse energy of charm and bottom jets at the Tevatron collider, with a complete study of the dependence on the jet cone-size and of the theoretical uncertainties.

hep-ph↗
arXiv1996

QCD in e+e- collisions at 2 TeV

We discuss some topics in QCD studies at 2 TeV. Particular emphasis is given to the separation of pure QCD events from the WW and the t-tbar backgrounds

hep-ph↗
arXiv1996

The Top Cross Section in Hadronic Collisions

We reexamine the top quark production cross section at the Tevatron and LHC, in the light of recent progress on the resummation of logarithmic soft gluon corrections. We find that resummation effects are much smaller than previously thought. We also compute Coulombic threshold effects, and find them negligible. We update the discussion of uncertainties due to scale dependence, the value of the strong coupling constant, and the parton density parametrization. Our current best estimate of the top production cross section at the Tevatron and its error is $σ(\mt=175\,{\rm GeV})=4.75{+0.73\atop-0.62}$.

hep-ph↗
arXiv1996

Searches For New Physics

Review of prospects for discovery of new physics signals at LEP2. The areas covered include SUSY, exotic fermions, BESS models, leptoquarks, virtual effects and CP violating observables.

hep-ph↗
arXiv1995

Charmonium Production at the Tevatron

We present in this work a study of large-\pt\ charmonium production in hadronic collisions. We work in the framework of the factorization model of Bodwin Braaten and Lepage, thereby including the color octet production mechanism, and extract the values of the necessary nonperturbative parameters from a comparison with the most recent data from the Fermilab 1.8 TeV $p\bar p$ hadron collider. We extend the calculation to 630 \gev, and compare the results with data published by the UA1 Collaboration. The global agreement is satisfactory, indicating that the largest components of the production mechanisms for charmonium production at high \pt\ have been isolated.

hep-ph↗
arXiv1995

An update on $χ_c$ Decays: Perturbative QCD versus Data

We present a global fit of current available experimental results on $χ_c$ decays within next-to-leading-order perturbative QCD. The quality and reduced errors of recent data improve the agreement between theory and experiment.

hep-ph↗
arXiv1995

Top Quark Distributions in Hadronic Collisions

We present kinematical distributions for top quark pairs produced at the Tevatron \ppbar\ Collider, as predicted within Next-to-Leading-Order QCD. We consider single and double-inclusive distributions, and compare our results to those obtained with the shower Monte Carlo HERWIG. We discuss the implications of our findings for experimental issues such as the measurement of the top quark mass.

hep-ph↗
arXiv1994

Total Cross Sections for Heavy Flavour Production at HERA

We compute total cross sections for charm and bottom photoproduction at HERA energies, and discuss the relevant theoretical uncertainties. In particular we discuss the problems arising from the small-$x$ region, the uncertainties in the gluon parton density, and the uncertainties in the hadronic component of the cross section. Total electroproduction cross sections, calculated in the Weizsäcker-Williams approximation, are also given.

hep-ph↗
arXiv1993

Improving the Weizsäcker-Williams Approximation in Electron-Proton Collisions

We critically examine the validity of the Weizsäcker-Williams approximation in electron-hadron collisions. We show that in its commonly used form it can lead to large errors, and we show how to improve it in order to get accurate results. In particular, we present an improved form that is valid beyond the leading logarithmic approximation in the case when a small-angle cut is applied to the scattered electron. Furthermore we include comparisons of the approximate expressions with the exact electroproduction calculation in the case of heavy-quark production.

hep-ph↗
arXiv1993

The Charm Content of W+1 Jet Events as a Probe of the Strange Quark Distribution Function

We investigate the prospects for measuring the strange quark distribution function of the proton in associated $W$ plus charm quark production at the Tevatron. The $W+c$ quark signal produced by strange quark -- gluon fusion, $sg\rightarrow W^-c$ and $\bar sg\rightarrow W^+\bar c$, is approximately 5\% of the inclusive $W+1$ jet cross section for jets with a transverse momentum $p_T(j)>10$~GeV. We study the sensitivity of the $W$ plus charm quark cross section to the parametrization of the strange quark distribution function, and evaluate the various background processes. Strategies to identify charm quarks in CDF and DØ\ are discussed. For a charm tagging efficiency of about 10\% and an integrated luminosity of 30~pb$^{-1}$ or more, it should be possible to constrain the strange quark distribution function from $W+c$ production at the Tevatron.

hep-ph↗
arXiv1993

Measurement of the Strange Quark Distribution Function in W + Charm Quark Events

We investigate the prospects of measuring the strange quark distribution function at the Tevatron, using $W$ plus charm quark events. The $W$ plus charm quark signal produced by strange quark--gluon fusion, $sg\rightarrow W^-c$ and $\bar sg\rightarrow W^+\bar c$, is approximately 5\% of the inclusive $W+1$ jet cross section for jets with a transverse momentum $p_T(j)>10$~GeV. We study the sensitivity of the $W$ plus charm quark cross section to the parametrization of the strange quark distribution function, and evaluate the various background processes. Strategies to identify charm quarks in CDF and D$0\llap/$ are briefly described.

hep-ph↗