A Feynman–Kac-type formula for Lévy processes with discontinuous killing rates

The roots of the present paper go back to the author’s dissertation [17], which was financially supported by the DFG through project EB66/11-1

Neutral pion and η meson production in p–Pb collisions at √sNN = 5.02 TeV

Neutral pion and η meson invariant differential yields were measured in non-single diffractive p–Pb collisions at sNN = 5.02 TeV with the ALICE experiment at the CERN LHC. The analysis combines results from three complementary photon measurements, utilizing the PHOS and EMCal calorimeters and the Photon Conversion Method. The invariant differential yields of π0 and η meson inclusive production are measured near mid-rapidity in a broad transverse momentum range of 0.3<pT<20GeV/c and 0.7<pT<20GeV/c, respectively. The measured η/ π0 ratio increases with pT and saturates for pT > 4 GeV / c at 0.483 ± 0. 015 stat± 0. 015 sys. A deviation from mT scaling is observed for pT< 2 GeV / c. The measured η/ π0 ratio is consistent with previous measurements from proton-nucleus and pp collisions over the full pT range. The measured η/ π0 ratio at high pT also agrees within uncertainties with measurements from nucleus–nucleus collisions. The π0 and η yields in p–Pb relative to the scaled pp interpolated reference, RpPb, are presented for 0.3 < pT< 20 GeV / c and 0.7 < pT< 20 GeV / c, respectively. The results are compared with theoretical model calculations. The values of RpPb are consistent with unity for transverse momenta above 2 GeV / c. These results support the interpretation that the suppressed yield of neutral mesons measured in Pb–Pb collisions at LHC energies is due to parton energy loss in the hot QCD medium. © 2018, CERN for the benefit of the ALICE collaboration

Relative particle yield fluctuations in Pb-Pb collisions at root s(NN)=2.76 TeV

First results on K / \u3c0, p / \u3c0 and K/p fluctuations are obtained with the ALICE detector at the CERN LHC as a function of centrality in Pb--Pb collisions at 1asNN=2.76TeV. The observable \u3bd dyn , which is defined in terms of the moments of particle multiplicity distributions, is used to quantify the magnitude of dynamical fluctuations of relative particle yields and also provides insight into the correlation between particle pairs. This study is based on a novel experimental technique, called the Identity Method, which allows one to measure the moments of multiplicity distributions in case of incomplete particle identification. The results for p / \u3c0 show a change of sign in \u3bd dyn from positive to negative towards more peripheral collisions. For central collisions, the results follow the smooth trend of the data at lower energies and \u3bd dyn exhibits a change in sign for p / \u3c0 and K/p

Transverse momentum spectra of charged particles in proton-proton collisions at 1as=900 GeV with ALICE at the LHC

The inclusive charged particle transverse momentum distribution is measured in proton-proton collisions at s=900 GeV at the LHC using the ALICE detector. The measurement is performed in the central pseudorapidity region (|\u3b7|<0.8) over the transverse momentum range 0.15<10 GeV/c. The correlation between transverse momentum and particle multiplicity is also studied. Results are presented for inelastic (INEL) and non-single-diffractive (NSD) events. The average transverse momentum for |\u3b7|<0.8 is \u3008pT\u3009INEL=0.483\ub10.001 (stat.)\ub10.007 (syst.) GeV/c and \u3008pT\u3009NSD=0.489\ub10.001 (stat.)\ub10.007 (syst.) GeV/c, respectively. The data exhibit a slightly larger \u3008pT\u3009 than measurements in wider pseudorapidity intervals. The results are compared to simulations with the Monte Carlo event generators PYTHIA and PHOJET. \ua9 2010