Measurement of deuteron spectra and elliptic flow in Pb-Pb collisions at $\sqrt{{\mathbf{s}}_{\mathrm{NN}}}$ = 2.76 TeV at the LHC

Abstract

The transverse momentum ($p_{\mathrm{T}}$) spectra and elliptic flow coefficient ($v_2$) of deuterons and anti-deuterons at mid-rapidity ($|y|<0.5$) are measured with the ALICE detector at the LHC in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV. The measurement of the $p_{\mathrm{T}}$ spectra of (anti-)deuterons is done up to 8 GeV/$c$ in 0-10% centrality class and up to GeV/$c$ in 10-20% and 20-40% centrality classes. The $v_2$ is measured in the $0.8<p_{\mathrm{T}}<5$ GeV/$c$ interval and in six different centrality intervals (0-5%, 5-10%, 10-20%, 20-30%, 30-40% and 40-50%) using the scalar product technique. Measured ${\pi }^{\pm }$, K${}^{\pm }$ and p+$\overline{\mathrm{p}}$ transverse-momentum spectra and $v_2$ are used to predict the deuteron $p_{\mathrm{T}}$ spectra and $v_2$ within the Blast-Wave model. The predictions are able to reproduce the $v_2$ coefficient in the measured $p_{\mathrm{T}}$ range and the transverse-momentum spectra for $p_{\mathrm{T}}>1.8$ GeV/$c$ within the experimental uncertainties. The measurement of the coalescence parameter $B_2$ is performed, showing a $p_{\mathrm{T}}$ dependence in contrast with the simplest coalescence model, which fails to reproduce also the measured $v_2$ coefficient. In addition, the coalescence parameter $B_2$ and the elliptic flow coefficient in the 20-40% centrality interval are compared with the AMPT model which is able, in its version without string melting, to reproduce the measured $v_2$($p_{\mathrm{T}}$) and the $B_2$($p_{\mathrm{T}}$) trend.

27 pages, 9 captioned figures, 3 tables, authors from page 22, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/3691

References in corpus (4)

• Scaling properties of azimuthal anisotropy in Au+Au and Cu+Cu collisions at sqrt(s_NN) = 200 GeV
• Elliptic flow of identified hadrons in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Effect of flow fluctuations and nonflow on elliptic flow methods
• Elliptic flow for phi mesons and (anti)deuterons in Au+Au collisions at sqrt(s_NN) = 200 GeV