Browsing by Subject "PERSPECTIVE"

Now showing 1 - 3 of 3
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    J/ψ suppression at forward rapidity in Pb–Pb collisions at √sNN = 5.02 TeV
    (2017) Adam, J; Adamová, D; Aggarwal, M M; Aglieri Rinella, G; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Aiola, S; Akindinov, A; Alam, S N; Albuquerque, D S D; Aleksandrov, D; Alessandro, B; Alexandre, D; Alfaro Molina, R; Alici, A; Alkin, A; Alme, J; Alt, T; Altinpinar, S; Altsybeev, I; Alves Garcia Prado, C; An, M; Andrei, C; Andrews, H A; Andronic, A; Anguelov, V; Anson, C; Antičić, T; Antinori, F
    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 the J/ ψ in nuclear collisions and are then compared to our previous results obtained in Pb–Pb collisions at sNN=2.76 TeV . The ratio of the RAA values at the two energies is also computed and compared to calculations of statistical and dynamical models. The numerical value of the ratio for central events (0–10% centrality) is 1.17±0.04(stat)±0.20(syst) . In central events, as a function of pT , a slight increase of RAA with collision energy is visible in the region 2 < pT < 6 GeV/c . Theoretical calculations qualitatively describe the measurements, within uncertainties.
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    Promoting equality for ethnic minority NHS staff—what works?
    (2015) Priest, Naomi; Esmail, Aneez; Kline, Roger; Rao, Mala; Coghill, Yvonne; Williams, David R
    NHS organisations are now being judged on indicators of ethnic diversity. Naomi Priest and colleagues look at the international evidence on how they should tackle discrimination
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    ϕ-Meson production at forward rapidity in p–Pb collisions at √sNN = 5.02 TeV and in pp collisions at √s = 2.76 TeV
    (2017) Adam, J; Adamová, D; Aggarwal, M M; Aglieri Rinella, G; Agnello, M; Agrawal, N; Ahammed, Z; Ahn, S U; Aimo, I; Aiola, S; Ajaz, M; Akindinov, A; Alam, S N; Aleksandrov, D; Alessandro, B; Alexandre, D; Alfaro Molina, R; Alici, A; Alkin, A; Almaraz, J R M; Alme, J; Alt, T; Altinpinar, S; Altsybeev, I; Alves Garcia Prado, C; Andrei, C; Andronic, A; Anguelov, V; Anielski, J; Antičić, T; Antinori, F; Antonioli, P
    The first measurement of $phi$-meson production in p-Pb collisions at a nucleon-nucleon centre-of-mass energy $sqrt{s_{rm NN}}$ = 5.02 TeV has been performed with the ALICE apparatus at the LHC. The $phi$-mesons have been identified in the dimuon decay channel in the transverse momentum ($p_{rm T}$) range $1 < p_{rm T} < 7$ GeV/$c$, both in the p-going ($2.03 < y < 3.53$) and the Pb-going ($-4.46 < y < -2.96$) directions, where $y$ stands for the rapidity in the nucleon-nucleon centre-of-mass. Differential cross sections as a function of transverse momentum and rapidity are presented. The forward-backward asymmetry for $phi$-meson production is measured for $2.96< y <3.53$, resulting in a factor $sim 0.5$ with no significant $p_{rm T}$ dependence within the uncertainties. The $p_{rm T}$ dependence of the $phi$ nuclear modification factor $R_{rm pPb}$ exhibits an enhancement up to a factor 1.6 at $p_{rm T}$ = 3-4 GeV/$c$ in the Pb-going direction. The $p_{rm T}$ dependence of the $phi$-meson cross section in pp collisions at $sqrt{s}$ = 2.76 TeV, which is used to determine a reference for the p-Pb results, is also presented here for $1 < p_{rm T} < 5$ GeV/$c$ and $2.5