14 research outputs found
Cross section of isolated prompt photons in hadron-hadron collisions
We consider the production of isolated prompt photons in hadronic collisions.
We present a general discussion in QCD perturbation theory of the isolation
criterion used by hadron collider experiments. The isolation criterion is
implemented in a computer programme of the Monte Carlo type, which evaluates
the production cross section at next-to-leading order accuracy in perturbative
QCD. The calculation includes both the direct and the fragmentation components
of the cross section, without any approximation of the dependence on the radius
R of the isolation cone. We examine the scale dependence of the isolated cross
section, the sensitivity of the cross section to the values of the isolation
parameters, and we provide a quantitative comparison between the full R
dependence and its small-R approximation.Comment: 29 pages, 1 figure, few comments slightly expanded, results
unchanged, misprints correcte
Large Transverse Momenta in Statistical Models of High Energy Interactions
The creation of particles with large transverse momenta in high energy
hadronic collisions is a long standing problem. The transition from small-
(soft) to hard- parton scattering `high-pt' events is rather smooth. In this
paper we apply the non-extensive statistical framework to calculate transverse
momentum distributions of long lived hadrons created at energies from low
(sqrt(s)~10 GeV) to the highest energies available in collider experiments
(sqrt(s)~2000 GeV). Satisfactory agreement with the experimental data is
achieved. The systematic increase of the non-extensivity parameter with energy
found can be understood as phenomenological evidence for the increased role of
long range correlations in the hadronization process.
Predictions concerning the rise of average transverse momenta up to the
highest cosmic ray energies are also given and discussed.Comment: 20 pages, 10 figure
Electroweak Physics at LHC
The prospects for electroweak physics at the LHC are reviewed focusing mainly on precision studies. This includes projections for measurements of the effective Z pole weak mixing angle, of top quark, W boson, and Higgs scalar properties, and new physics searches
Re-evaluation of the LHC potential for the measurement of Mw
We present a study of the LHC sensitivity to the W boson mass based on
simulation studies. We find that both experimental and phenomenological sources
of systematic uncertainties can be strongly constrained with Z measurements:
the lineshape is robustly predicted, and its analysis provides an accurate
measurement of the detector resolution and absolute scale, while the
differential cross-section analysis absorbs most of the strong interaction
uncertainties. A sensitivity \delta Mw \sim 7 \MeV for each decay channel (W
--> e nu, W --> mu nu), and for an integrated luminosity of 10 fb-1, appears as
a reasonable goal