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

Search for resonances in the mass spectrum of muon pairs produced in association with b quark jets in proton-proton collisions at root 8 and 13 TeV

A search for resonances in the mass range 12-70 GeV produced in association with a b quark jet and a second jet, and decaying to a muon pair, is reported. The analysis is based on data from proton-proton collisions at center-of-mass energies of 8 and 13 TeV, collected with the CMS detector at the LHC and corresponding to integrated luminosities of 19.7 and 35.9 fb(-1), respectively. The search is carried out in two mutually exclusive event categories. Events in the first category are required to have a b quark jet in the central region (|| 2.4) and at least one jet in the forward region (|| > 2.4). Events in the second category are required to have two jets in the central region, at least one of which is identified as a b quark jet, no jets in the forward region, and low missing transverse momentum. An excess of events above the background near a dimuon mass of 28 GeV is observed in the 8 TeV data, corresponding to local significances of 4.2 and 2.9 standard deviations for the first and second event categories, respectively. A similar analysis conducted with the 13 TeV data results in a mild excess over the background in the first event category corresponding to a local significance of 2.0 standard deviations, while the second category results in a 1.4 standard deviation deficit. The fiducial cross section measurements and 95% confidence level upper limits on those for a resonance consistent with the 8 TeV excess are provided at both collision energies

Search for new physics with dijet angular distributions in proton-proton collisions at root S = 13 TeV

Peer reviewe

Dependence of inclusive jet production on the anti-k(T) distance parameter in pp collisions at root s=13 TeV

Peer reviewe

Cross section measurement of t-channel single top quark production in pp collisions at root s=13 TeV

Peer reviewe

Search for R-parity violating supersymmetry with displaced vertices in proton-proton collisions at root s=8 TeV

Peer reviewe

Searches for lepton-flavour-violating decays of the Higgs boson into eτ and μτ in \sqrt{s} = 13 TeV pp collisions with the ATLAS detector

Abstract This paper presents direct searches for lepton flavour violation in Higgs boson decays, H → eτ and H → μτ, performed using data collected with the ATLAS detector at the LHC. The searches are based on a data sample of proton-proton collisions at a centre-of-mass energy s $$\sqrt{s}$$ = 13 TeV, corresponding to an integrated luminosity of 138 fb−1. Leptonic (τ → ℓνℓντ) and hadronic (τ → hadrons ντ) decays of the τ-lepton are considered. Two background estimation techniques are employed: the MC-template method, based on data-corrected simulation samples, and the Symmetry method, based on exploiting the symmetry between electrons and muons in the Standard Model backgrounds. No significant excess of events is observed and the results are interpreted as upper limits on lepton-flavour-violating branching ratios of the Higgs boson. The observed (expected) upper limits set on the branching ratios at 95% confidence level, B $$\mathcal{B}$$ (H → eτ) < 0.20% (0.12%) and B $$\mathcal{B}$$ (H → μτ ) < 0.18% (0.09%), are obtained with the MC-template method from a simultaneous measurement of potential H → eτ and H → μτ signals. The best-fit branching ratio difference, B $$\mathcal{B}$$ (H → μτ) → B $$\mathcal{B}$$ (H → eτ), measured with the Symmetry method in the channel where the τ-lepton decays to leptons, is (0.25 ± 0.10)%, compatible with a value of zero within 2.5σ

Combination of Searches for Higgs Boson Pair Production in Proton-Proton Collisions at root s=13 TeV

This Letter describes a search for Higgs boson pair production using the combined results from four final states: bb gamma gamma, bb tau tau, bbbb, and bbVV, where V represents a W or Z boson. The search is performed using data collected in 2016 by the CMS experiment from LHC proton-proton collisions at root s = 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). Limits are set on the Higgs boson pair production cross section. A 95% confidence level observed (expected) upper limit on the non-resonant production cross section is set at 22.2 (12.8) times the standard model value. A search for narrow resonances decaying to Higgs boson pairs is also performed in the mass range 250-3000 GeV. No evidence for a signal is observed, and upper limits are set on the resonance production cross section.Peer reviewe

Observation of prompt J/psi meson elliptic flow in high-multiplicity pPb collisions at root s(NN)=8.16 TeV

A measurement of the elliptic flow (v(2)) of prompt J/psi mesons in high-multiplicity pPbcollisions is reported using data collected by the CMS experiment at a nucleon-nucleon center-of-mass energy root s(NN)= 8.16 TeV. Prompt J/psi mesons decaying into two muons are reconstructed in the rapidity region in the nucleon-nucleon center-of-mass frame (y(cm)), corresponding to either -2.86 < y(cm) < -1.86 or 0.94 < y(cm)< 1.94. The average v(2) result from the two rapidity ranges is reported over the transverse momentum (p(T)) range from 0.2 to 10 GeV. Positive v(2) values are observed for the prompt J/psi meson, as extracted from long-range two-particle correlations with charged hadrons, for 2 < p(T) < 8 GeV. The prompt J/psi results are compared with previous CMS measurements of elliptic flow for open charm mesons (D-0) and strange hadrons. From these measurements, constraints can be obtained on the collective dynamics of charm quarks produced in high-multiplicity events arising from small systems. (c) 2019 The Author(s). Published by Elsevier B.V.Peer reviewe

Evidence of off-shell Higgs boson production from ZZ leptonic decay channels and constraints on its total width with the ATLAS detector

This Letter reports on a search for off-shell production of the Higgs boson using 139 fb(-1) of pp collision data at root s = 13 TeV collected by the ATLAS detector at the Large Hadron Collider. The signature is a pair of Z bosons, with contributions from both the production and subsequent decay of a virtual Higgs boson and the interference of that process with other processes. The two observable final states are ZZ -&gt; 4l and Z Z -&gt; 2l2 nu with l = e or mu. In the ZZ -&gt; 4l final state, a dense Neural Network is used to enhance analysis sensitivity with respect to matrix element-based discrimination. The background-only hypothesis is rejected with an observed (expected) significance of 3.3 (2.2) standard deviations, representing experimental evidence for off-shell Higgs boson production. Assuming that no new particles enter the production of the virtual Higgs boson, its total width can be deduced from the measurement of its off-shell production cross-section. The measured total width of the Higgs boson is 4.5(-2.5)(+3.3) MeV, and the observed (expected) upper limit on the total width is found to be 10.5 (10.9) MeV at 95% confidence level. (c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)