Mass Distribution Of Jet Pairs Research Articles

Search for resonances in the mass distribution of jet pairs with one or two jets identified as b -jets in proton-proton collisions at s=13 TeV with the ATLAS detector

A search for new resonances decaying into jets containing b-hadrons in $pp$ collisions with the ATLAS detector at the LHC is presented in the dijet mass range from 0.57 TeV to 7 TeV. The dataset corresponds to an integrated luminosity of up to 36.1 fb$^{-1}$ collected in 2015 and 2016 at $\sqrt{s} = 13$ TeV. No evidence of a significant excess of events above the smooth background shape is found. Upper cross-section limits and lower limits on the corresponding signal mass parameters for several types of signal hypotheses are provided at 95% CL. In addition, 95% CL upper limits are set on the cross-sections for new processes that would produce Gaussian-shaped signals in the di-b-jet mass distributions.

Search for resonances in the mass distribution of jet pairs with one or two jets identified as b-jets in proton–proton collisions at s=13 TeV with the ATLAS detector

Searches for high-mass resonances in the dijet invariant mass spectrum with one or two jets identified as $b$-jets are performed using an integrated luminosity of $3.2$ fb$^{-1}$ of proton--proton collisions with a centre-of-mass energy of $\sqrt{s}=13$ TeV recorded by the ATLAS detector at the Large Hadron Collider. No evidence of anomalous phenomena is observed in the data, which are used to exclude, at 95% credibility level, excited $b^{*}$ quarks with masses from 1.1 TeV to 2.1 TeV and leptophobic $Z'$ bosons with masses from 1.1 TeV to 1.5 TeV. Contributions of a Gaussian signal shape with effective cross sections ranging from approximately 0.4 to 0.001 pb are also excluded in the mass range 1.5-5.0 TeV.

W+jets in pp collisions at 7 TeV with ATLAS

Measurements of differential cross-sections of W boson production in association with jets, and jets containing b hadrons are presented. The measurements are based on 35 pb − 1 of pp collisions at \(\sqrt{s}=7\) TeV collected with the ATLAS detector at the LHC, using the electron and muon decay channels of the W boson. The data are found to be compatible with next-to-leading order predictions. In addition, a study of the invariant mass distribution of jet pairs produced in association with a W boson is presented, based on an integrated luminosity of 1.02 \({\mbox{fb$^{-1}$}}\). The measured dijet mass shows no significant excess over the Standard Model expectation.

CDF Wjj ANOMALY AS A NONPERTURBATIVE EFFECT OF THE ELECTROWEAK INTERACTION

The recently reported CDF excess at 120–160 GeV in invariant mass distribution of jet pairs accompanying W-boson1 is tentatively interpreted as a bound state of two W decaying to quark–antiquark pair. Nonperturbative effects of EW interaction obtained by application of Bogoliubov compensation approach lead to such bound state due to existence of anomalous three-boson gauge-invariant effective interaction. The application of this scheme gives satisfactory agreement with existing data without any adjusting parameter but the bound state mass 145 GeV.

W plus two jets from a quasi-inert Higgs doublet

We show that, the result recently reported by the CDF collaboration showing an excess in the invariant mass distribution of jet pairs produced in association with a W-boson can be explained by a simple extension of the Standard Model (SM) with an additional quasi-inert Higgs doublet. The two additional neutral Higgs states H 0 and A 0 have a mass of about 150 GeV and decay into a pair of jets. W ± H 0/A 0 pairs are produced from the decay of the heavier charged Higgs boson H ±. Depending on the precise masses of the neutral and charged Higgs bosons, the model is shown to be in agreement with constraints from electroweak precision tests and from flavor physics for a broad range of the Standard Model-like Higgs mass from 100 GeV to several hundreds of GeV. Other possible signals of this model at the Tevatron and the LHC are discussed.

Invariant Mass Distribution of Jet Pairs Produced in Association with aWBoson inpp¯Collisions ats=1.96 TeV

We report a study of the invariant mass distribution of jet pairs produced in association with a W boson using data collected with the CDF detector which correspond to an integrated luminosity of 4.3 fb^-1. The observed distribution has an excess in the 120-160 GeV/c^2 mass range which is not described by current theoretical predictions within the statistical and systematic uncertainties. In this letter we report studies of the properties of this excess.

Search for decays of the W ± and Z bosons into quark-antiquark pairs

The invariant mass distribution of jet pairs observed in the UA2 central calorimeter is examined in the search for an excess of events in the region of the W ± and Z bosons, which would reveal their decays into quark-antiquark pairs. We give a detailed account of the methods of analysis used to optimize the mass resolution achieving ≅±10%. A structure is observed at the level of ≅ 3 standard deviations in the mass region of W ± and Z with shape and position consistent with expectation from their qq̄decays. It contains 632 ± 190 events, 1.4 standard deviations above the standard model prediction of 340 ± 80 events.