Search results for "collisions"
showing 10 items of 558 documents
J/ψ suppression at forward rapidity in Pb–Pb collisions at √sNN = 5.02 TeV
2017
The inclusive J/ψ production has been studied in Pb–Pb and pp collisions at the centre-of-mass energy per nucleon pair √sNN = 5.02 TeV, using the ALICE detector at the CERN LHC. The J/ψ meson is reconstructed, in the centre-of-mass rapidity interval 2.5 < y < 4 and in the transverse-momentum range pT < 12 GeV/c, via its decay to a muon pair. In this Letter, we present results on the inclusive J/ψ cross section in pp collisions at √s = 5.02 TeV and on the nuclear modification factor RAA. The latter is presented as a function of the centrality of the collision and, for central collisions, as a function of the transverse momentum pT of the J/ψ. The measured RAA values indicate a suppression of…
Forward J/ψ production in U+U collisions at √sNN = 193 GeV
2016
The invariant yields, dN/dy, for J/ψ production at forward rapidity (1.2 < |y| < 2.2) in U + U collisions at √sNN = 193 GeV have been measured as a function of collision centrality. The invariant yields and nuclearmodification factor RAA are presented and compared with those from Au + Au collisions in the same rapidity range. Additionally, the direct ratio of the invariant yields from U + U and Au + Au collisions within the same centrality class is presented, and used to investigate the role of cc¯ coalescence. Two different parametrizations of the deformed Woods-Saxon distribution were used in Glauber calculations to determine the values of the number of nucleon-nucleon collisions in each …
Search for collectivity with azimuthal J/ψ -hadron correlations in high multiplicity p–Pb collisions at √sNN = 5.02 and 8.16 TeV
2018
We present a measurement of azimuthal correlations between inclusive J/ψ and charged hadrons in p–Pb collisions recorded with the ALICE detector at the CERN LHC. The J/ψ are reconstructed at forward (p-going, ) and backward (Pb-going, ) rapidity via their decay channel, while the charged hadrons are reconstructed at mid-rapidity (). The correlations are expressed in terms of associated charged-hadron yields per J/ψ trigger. A rapidity gap of at least 1.5 units is required between the trigger J/ψ and the associated charged hadrons. Possible correlations due to collective effects are assessed by subtracting the associated per-trigger yields in the low-multiplicity collisions from those in the…
"Table 47" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"
2020
K$^{*0}$/K$_{\mathrm{S}}^{0}$ yield ratio vs transverse momentum - V0M multiplicity class II, average of particle and antiparticle
"Table 43" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"
2020
K$^{*0}$/K$_{\mathrm{S}}^{0}$ transverse momentum integrated yield ratio vs multiplicity - V0M multiplicity classes, average of particle and antiparticle
"Table 48" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"
2020
K$^{*0}$/K$_{\mathrm{S}}^{0}$ yield ratio vs transverse momentum - V0M multiplicity class X, average of particle and antiparticle
Accessing the gluonic structure of light nuclei at a future electron-ion collider
2020
We show how exclusive vector meson production off light ions can be used to probe the spatial distribution of small-$x$ gluons in the deuteron and $^3$He wave functions. In particular, we demonstrate how short range repulsive nucleon-nucleon interactions affect the predicted coherent $J/\Psi$ production spectra. Fluctuations of the nucleon substructure are shown to have a significant effect on the incoherent cross section above $|t|\gtrsim 0.2\,\mathrm{GeV}^2$. By explicitly performing the JIMWLK evolution, we predict the $x$-dependence of coherent and incoherent cross sections in the EIC energy range. Besides the increase of the average size of the nucleus with decreasing $x$, both the gro…
Search for Magnetic Monopoles with the MoEDAL Forward Trapping Detector in 13 TeV Proton-Proton Collisions at the LHC
2017
MoEDAL is designed to identify new physics in the form of long-lived highly-ionising particles produced in high-energy LHC collisions. Its arrays of plastic nuclear-track detectors and aluminium trapping volumes provide two independent passive detection techniques. We present here the results of a first search for magnetic monopole production in 13 TeV proton-proton collisions using the trapping technique, extending a previous publication with 8 TeV data during LHC run-1. A total of 222 kg of MoEDAL trapping detector samples was exposed in the forward region and analysed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges excee…
Update of the search for supersymmetric particles in scenarios with Gravitino LSP and Sleptons NLSP
2001
An update of the search for sleptons, neutralinos and charginos in the context of scenarios where the lightest supersymmetric particle is the gravitino and the next-to-lightest supersymmetric particle is a slepton, is presented, together with the update of the search for heavy stable charged particles in light gravitino scenarios and Minimal Supersymmetric Standard Models. Data collected in 1999 with the DELPHI detector at centre-of-mass energies around 192, 196, 200 and 202 GeV were analysed. No evidence for the production of these supersymmetric particles was found. Hence, new mass limits were derived at 95% confidence level.
Photon events with missing energy at root s=183 to 189 GeV
2000
The production of single photons has been studied in the reaction e+e- -> gamma + invisible particles at centre-of-mass energies of 183 GeV and 189 GeV. A previously published analysis of events with multi-photon final states accompanied by missing energy has been updated with 189 GeV data. The data were collected with the DELPHI detector and correspond to integrated luminosities of about 51 pb^{-1} and 158 pb^{-1} at the two energies. The number of light neutrino families is measured to be 2.84 +/- 0.15(stat) +/- 0.14(syst). The absence of an excess of events beyond that expected from Standard Model processes is used to set limits on new physics as described by supersymmetric and compos…