Compressed representation of a partially defined integer function over multiple arguments

In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one

Measurement of the triple-differential cross section for photon plus jets production in proton-proton collisions at √s = 7 TeV

Peer reviewe

Search for massive resonances in dijet systems containing jets tagged as W or Z boson decays in pp collisions at √s=8 TeV

Peer reviewe

Measurement of the t-channel single-top-quark production cross section and of the |V tb| CKM matrix element in pp collisions at √s = 8 TeV

Peer reviewe

Study of the production of charged pions, kaons, and protons in pPb collisions at √SNN=5.02 TeV

Peer reviewe

Evidence for the 125 GeV Higgs boson decaying to a pair of tau leptons

A search for a standard model Higgs boson decaying into a pair of τ leptons is performed using events recorded by the CMS experiment at the LHC in 2011 and 2012. The dataset corresponds to an integrated luminosity of 4.9 fb −1 at a centre-of-mass energy of 7 TeV and 19.7 fb −1 at 8 TeV. Each τ lepton decays hadronically or leptonically to an electron or a muon, leading to six different final states for the τ -lepton pair, all considered in this analysis. An excess of events is observed over the expected background contributions, with a local significance larger than 3 standard deviations for m H values between 115 and 130 GeV. The best fit of the observed H → τ τ signal cross section times branching fraction for m H = 125 GeV is 0 . 78 ± 0 . 27 times the standard model expectation. These observations constitute evidence for the 125 GeV Higgs boson decaying to a pair of τ leptons

Jet and underlying event properties as a function of charged-particle multiplicity in proton-proton collisions at √s=7 TeV

This is the pre-print version of the final published paper that is available from the link belowCharacteristics of multi-particle production in proton-proton collisions at √s=7 TeV are studied as a function of the charged-particle multiplicity, N. The produced particles are separated into two classes: those belonging to jets and those belonging to the underlying event. Charged particles are measured with pseudorapidity |η|0.25 GeV/c. Jets are reconstructed from charged-particles only and required to have p>5 GeV/c. The distributions of jet p, average p of charged particles belonging to the underlying event or to jets, jet rates, and jet shapes are presented as functions of N and compared to the predictions of the pythia and herwig event generators. Predictions without multi-parton interactions fail completely to describe the N-dependence observed in the data. For increasing N, pythia systematically predicts higher jet rates and harder p spectra than seen in the data, whereas herwig shows the opposite trends. At the highest multiplicity, the data-model agreement is worse for most observables, indicating the need for further tuning and/or new model ingredients

Measurement of the W-boson helicity in top-quark decays from t(t)over-bar production in lepton plus jets events in pp collisions at √s=7 TeV

This is the pre-print version of the final published article that can be accessed at the link below.The W-boson helicity fractions in top-quark decays are measured with tt events in the lepton+jets final state, using proton-proton collisions at a centre-of-mass energy of 7 TeV, collected in 2011 with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 5.0 fb-1. The measured fractions of longitudinal, left-, and right-handed helicity are F0 = 0.682 0.030 (stat.) 0.033 (syst.), FL = 0.310 0.022 (stat.) 0.022 (syst.), and FR = 0.008 0.012 (stat.) 0.014 (syst.), consistent with the standard model predictions. The measured fractions are used to probe the existence of anomalous Wtb couplings. Exclusion limits on the real components of the anomalous couplings gL, gR are also derived