Search results for "Parto"
showing 10 items of 608 documents
Double parton correlations in Light-Front constituent quark models
2014
Double parton distribution functions (dPDF) represent a tool to explore the 3D proton structure. They can be measured in high energy proton-proton and proton nucleus collisions and encode information on how partons inside a proton are correlated among each other. dPFDs are studied here in the valence quark region, by means of a constituent quark model, where two particle correlations are present without any additional prescription. This framework allows to understand the dynamical origin of the correlations and to clarify which, among the features of the results, are model independent. Use will be made of a relativistic light-front scheme, able to overcome some drawbacks of the previous cal…
Measurement of electrons from semileptonic heavy-flavour hadron decays at midrapidity in pp and Pb–Pb collisions at sNN=5.02 TeV
2020
The differential invariant yield as a function of transverse momentum (pT) of electrons from semileptonic heavy-flavour hadron decays was measured at midrapidity in central (0–10%), semi-central (30–50%) and peripheral (60–80%) lead–lead (Pb–Pb) collisions at sNN=5.02 TeV in the pT intervals 0.5–26 GeV/c (0–10% and 30–50%) and 0.5–10 GeV/c (60–80%). The production cross section in proton–proton (pp) collisions at s=5.02 TeV was measured as well in 0.5<pT<10 GeV/c and it lies close to the upper band of perturbative QCD calculation uncertainties up to pT=5 GeV/c and close to the mean value for larger pT. The modification of the electron yield with respect to what is expected for an inco…
Three-particle correlations in QCD parton showers
2011
Three-particle correlations in quark and gluon jets are computed for the first time in perturbative QCD. We give results in the double logarithmic approximation and the modified leading logarithmic approximation. In both resummation schemes, we use the formalism of the generating functional and solve the evolution equations analytically from the steepest descent evaluation of the one-particle distribution. We thus provide a further test of the local parton hadron duality and make predictions for the LHC.
Three-particle correlations in QCD jets and beyond
2011
In this paper, we present a more detailed version of our previous work for three-particle correlations in quark and gluon jets [1]. We give theoretical results for this observable in the double logarithmic approximation and the modified leading logarithmic approximation. In both resummation schemes, we use the formalism of the generating functional and solve the evolution equations analytically from the steepest descent evaluation of the one-particle distribution. In addition, in this paper we include predictions beyond the limiting spectrum approximation and study this observable near the hump of the single inclusive distribution. We thus provide a further test of the local parton hadron d…
Reconciling open charm production at the Fermilab Tevatron with QCD
2005
We study the inclusive hadrodroduction of D^0, D^+, D^{*+}, and D_s^+ mesons at next-to-leading order in the parton model of quantum chromodynamics endowed with universal non-perturbative fragmentation functions (FFs) fitted to e^+e^- annihilation data from CERN LEP1. Working in the general-mass variable-flavor-number scheme, we resum the large logarithms through the evolution of the FFs and, at the same time, retain the full dependence on the charm-quark mass without additional theoretical assumptions. In this way, the cross section distributions in transverse momentum recently measured by the CDF Collaboration in run II at the Fermilab Tevatron are described within errors.
Hard and soft probe - medium interactions in a 3D hydro+micro approach at RHIC
2007
We utilize a 3D hybrid hydro+micro model for a comprehensive and consistent description of soft and hard particle production in ultra-relativistic heavy-ion collisions at RHIC. In the soft sector we focus on the dynamics of (multi-)strange baryons, where a clear strangeness dependence of their collision rates and freeze-out is observed. In the hard sector we study the radiative energy loss of hard partons in a soft medium in the multiple soft scattering approximation. While the nuclear suppression factor $R_{AA}$ does not reflect the high quality of the medium description (except in a reduced systematic uncertainty in extracting the quenching power of the medium), the hydrodynamical model a…
Note orientative per l’assistente di reparto
2013
Riflessioni sulle giurisdizioni. Il riparto di giurisdizione e la tutela delle situazioni soggettive dopo il codice del processo amminisrativo
2018
Il volume affronta il tema del riparto di giurisdizione alla luce delle novità introdotte dal Codice del processo amministrativo e dei più recenti orientamenti della Corte di Cassazione
Il riparto di competenze tra l’Unione europea e gli Stati: ossificazione o fluidità
2010
La riforma dei Trattati modifica il riparto di competenze tra l’Unione europea e gli Stati membri? Il sistema diviene chiuso e rigido? Ne deriva una dequotazione dell’ordinamento europeo? L’ipotesi di lavoro del presente commento è che, al di là degli accenti retorici, il meccanismo di riparto è rimasto flessibile e, quindi, immutato in profondità. L’allocazione delle competenze scaturirà ancora dall’interazione tra governi (Consiglio), Commissione, Parlamento europeo, Corte di giustizia e, ora anche, parlamenti nazionali. Pericoli per l’integrazione non si celano tanto nelle modifiche ai trattati, quanto nei mutamenti dell’ethos europeo indotti da pronunce come quella della Corte costituzi…
Riparto di giurisdizione. Rapporti tra Ssn e strutture private accreditate. Procedure di evidenza pubblica e contratto
2012
L'articolo affronta, in generale, la questione della qualificazione dei rapporti, tra concessione e contratto, nonché della connessione tra evidenza pubblica e contratto ai fini del riparto di giurisdizione