Search results

The PHENIX experiment at the Relativistic Heavy Ion Collider has measured φ meson production and its nuclear modification in asymmetric Cu+Au heavy-ion collisions at sNN=200 GeV at both forward Cu-going direction (1.2

The performance of the ATLAS muon trigger system is evaluated with proton-proton (pp) and heavy-ion (HI) collision data collected in Run 2 during 2015-2018 at the Large Hadron Collider. It is primarily evaluated using events containing a pair of muons from the decay of Z bosons to cover the intermediate momentum range between 26 GeV and 100 GeV. Overall, the efficiency of the single-muon triggers

The pseudorapidity (η) and transverse-momentum (pT) distributions of charged particles produced in proton–proton collisions are measured at the centre-of-mass energy s=13 TeV. The pseudorapidity distribution in |η|<1.8 is reported for inelastic events and for events with at least one charged particle in |η|<1. The pseudorapidity density of charged particles produced in the pseudorapidity region |η

We present measurements of the azimuthal dependence of charged jet production in central and semi-central sNN=2.76 TeV Pb–Pb collisions with respect to the second harmonic event plane, quantified as v2 ch jet. Jet finding is performed employing the anti-kT algorithm with a resolution parameter R=0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy o

The production of the hypertriton nuclei HΛ3 and H[U+203E]Λ-3 has been measured for the first time in Pb-Pb collisions at sNN=2.76 TeV with the ALICE experiment at LHC. The pT-integrated HΛ3 yield in one unity of rapidity, dN/dy×B.R.(HΛ3→He3,π-)=(3.86±0.77(stat.)±0.68(syst.))×10-in the 0-10% most central collisions, is consistent with the predictions from a statistical thermal model using the same

The centrality dependence of the charged-particle pseudorapidity density measured with ALICE in Pb-Pb collisions at √sNN=2.76 TeV over a broad pseudorapidity range is presented. This Letter extends the previous results reported by ALICE to more peripheral collisions. No strong change of the overall shape of charged-particle pseudorapidity density distributions with centrality is observed, and when

Direct photon production at mid-rapidity in Pb–Pb collisions at sNN=2.76 TeV was studied in the transverse momentum range 0.9

A search for dark matter in association with a Higgs boson decaying to two photons is presented. This study is based on data collected with the ATLAS detector, corresponding to an integrated luminosity of 36.1 fb-1 of proton-proton collisions at the LHC at a center-of-mass energy of 13 TeV in 2015 and 2016. No significant excess over the expected background is observed. Upper limits at 95% confide

Experimental results are presented on event-by-event net-proton fluctuation measurements in Pb–Pb collisions at sNN=2.76 TeV, recorded by the ALICE detector at the CERN LHC. These measurements have as their ultimate goal an experimental test of Lattice QCD (LQCD) predictions on second and higher order cumulants of net-baryon distributions to search for critical behavior near the QCD phase boundary

A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production in association with a top quark pair (tt¯H) or single top quark (tH) is studied. The analysis uses 139 fb-1 of proton-proton collision data recorded at a center-of-mass energy of

A search for long-lived particles decaying into hadrons and at least one muon is presented. The analysis selects events that pass a muon or missing-transverse-momentum trigger and contain a displaced muon track and a displaced vertex. The analyzed dataset of proton-proton collisions at s=13 TeV was collected with the ATLAS detector and corresponds to 136 fb-1. The search employs dedicated reconstr

We report on the inclusive production cross sections of (Formula presented.) , (Formula presented.) , (Formula presented.) (1S), (Formula presented.) (2S) and (Formula presented.) (3S), measured at forward rapidity with the ALICE detector in (Formula presented.) collisions at a center-of-mass energy (Formula presented.)  TeV. The analysis is based on data collected at the LHC and corresponds to an

We report the first results of elliptic (v2), triangular (v3), and quadrangular (v4) flow of charged particles in Pb-Pb collisions at a center-of-mass energy per nucleon pair of √sNN=5.02  TeV with the ALICE detector at the CERN Large Hadron Collider. The measurements are performed in the central pseudorapidity region |η|<0.8 and for the transverse momentum range 0.2

The production of K∗(892)0 and ϕ(1020) mesons has been measured in p–Pb collisions at sNN= 5.02 TeV. K∗ 0 and ϕ are reconstructed via their decay into charged hadrons with the ALICE detector in the rapidity range - 0.5 < y< 0. The transverse momentum spectra, measured as a function of the multiplicity, have a pT range from 0 to 15 GeV/c for K∗ 0 and from 0.3 to 21 GeV/c for ϕ. Integrated yields, m

A search for the electroweak production of charginos, neutralinos and sleptons decaying into final states involving two or three electrons or muons is presented. The analysis is based on 36.1 fb−1 of √s = 13 TeV proton– proton collisions recorded by the ATLAS detector at the Large Hadron Collider. Several scenarios based on simplified models are considered. These include the associated production

A detailed study of pseudorapidity densities and multiplicity distributions of primary charged particles produced in proton–proton collisions, at s= 0.9, 2.36, 2.76, 7 and 8 TeV, in the pseudorapidity range | η| < 2 , was carried out using the ALICE detector. Measurements were obtained for three event classes: inelastic, non-single diffractive and events with at least one charged particle in the p

We present results on transverse momentum (pT) and rapidity (y) differential production cross sections, mean transverse momentum and mean transverse momentum square of inclusive J / ψ and ψ(2 S) at forward rapidity (2.5 < y< 4) as well as ψ(2 S) -to-J / ψ cross section ratios. These quantities are measured in pp collisions at center of mass energies s=5.02 and 13 TeV with the ALICE detector. Both

The transverse momentum distributions of the strange and double-strange hyperon resonances (Σ (1385) ±, Ξ (1530) 0) produced in p–Pb collisions at sNN=5.02 TeV were measured in the rapidity range - 0.5 < yCMS< 0 for event classes corresponding to different charged-particle multiplicity densities, ⟨ dNch/dηlab⟩. The mean transverse momentum values are presented as a function of ⟨ dNch/dηlab⟩ , as w

A search for heavy resonances decaying into a Higgs boson (H) and a new particle (X) is reported, utilizing 36.1 fb−1 of proton–proton collision data at s=13TeV collected during 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. The particle X is assumed to decay to a pair of light quarks, and the fully hadronic final state XH→qq¯′bb¯ is analysed. The search considers the reg

A measurement of beauty hadron production at mid-rapidity in proton-lead collisions at a nucleon–nucleon centre-of-mass energy sNN=5.02 TeV is presented. The semi-inclusive decay channel of beauty hadrons into J / ψ is considered, where the J / ψ mesons are reconstructed in the dielectron decay channel at mid-rapidity down to transverse momenta of 1.3 GeV/c. The b b ¯ production cross section at m