0000000000274185

AUTHOR

Bibhav Acharya

showing 3 related works from this author

Search for Higgs Boson Decays into a Z Boson and a Light Hadronically Decaying Resonance Using 13 TeV pp Collision Data from the ATLAS Detector

2020

A search for Higgs boson decays into a Z boson and a light resonance in two-lepton plus jet events is performed, using a pp collision dataset with an integrated luminosity of 139  fb^{-1} collected at sqrt[s]=13  TeV by the ATLAS experiment at the CERN LHC. The resonance considered is a light boson with a mass below 4 GeV from a possible extended scalar sector or a charmonium state. Multivariate discriminants are used for the event selection and for evaluating the mass of the light resonance. No excess of events above the expected background is found. Observed (expected) 95% confidence-level upper limits are set on the Higgs boson production cross section times branching fraction to a Z bos…

PhysicsTop quarkParticle physicsLarge Hadron ColliderBranching fractionHigh Energy Physics::PhenomenologyATLAS experimentGeneral Physics and Astronomy01 natural sciencesPair production0103 physical sciencesHiggs bosonHigh Energy Physics::Experiment010306 general physicsLeptonBosonPhysical Review Letters
researchProduct

Medium-Induced Modification of Z -Tagged Charged Particle Yields in Pb+Pb Collisions at 5.02 TeV with the ATLAS Detector

2021

The yield of charged particles opposite to a Z boson with large transverse momentum (p_{T}) is measured in 260  pb^{-1} of pp and 1.7  nb^{-1} of Pb+Pb collision data at 5.02 TeV per nucleon pair recorded with the ATLAS detector at the Large Hadron Collider. The Z boson tag is used to select hard-scattered partons with specific kinematics, and to observe how their showers are modified as they propagate through the quark-gluon plasma created in Pb+Pb collisions. Compared with pp collisions, charged-particle yields in Pb+Pb collisions show significant modifications as a function of charged-particle p_{T} in a way that depends on event centrality and Z boson p_{T}. The data are compared with a…

PhysicsLarge Hadron ColliderPhotonHigh Energy Physics::PhenomenologyGeneral Physics and AstronomyParton7. Clean energy01 natural sciencesCharged particleNuclear physicsmedicine.anatomical_structureAtlas (anatomy)0103 physical sciencesQuark–gluon plasmamedicineHigh Energy Physics::ExperimentNuclear Experiment010306 general physicsNucleonBosonPhysical Review Letters
researchProduct

Search for Dark Matter Produced in Association with a Dark Higgs Boson Decaying into W±W∓ or ZZ in Fully Hadronic Final States from s=13  TeV pp Coll…

2021

Several extensions of the Standard Model predict the production of dark matter particles at the LHC. An uncharted signature of dark matter particles produced in association with VV=W^{±}W^{∓} or ZZ pairs from a decay of a dark Higgs boson s is searched for using 139  fb^{-1} of pp collisions recorded by the ATLAS detector at a center-of-mass energy of 13 TeV. The s→V(qq[over ¯])V(qq[over ¯]) decays are reconstructed with a novel technique aimed at resolving the dense topology from boosted VV pairs using jets in the calorimeter and tracking information. Dark Higgs scenarios with m_{s}>160  GeV are excluded.

PhysicsParticle physicsTop quarkLarge Hadron ColliderHigh Energy Physics::PhenomenologyDark matterGeneral Physics and Astronomy01 natural sciences7. Clean energyGalaxyStandard ModelHidden sector0103 physical sciencesHiggs bosonHigh Energy Physics::Experiment010306 general physicsBosonPhysical Review Letters
researchProduct