Measurement of the inclusive J/psi polarization at forward rapidity in pp collisions at root s=8 TeV

S. Acharya, F Acosta, D. Adamova, Jan Adolfsson, MM. Aggarwal, G.A. Rinella, Maria Agnello, N. Agrawal, Z. Ahammed, S.U. Ahn, S. Aiola, A. Akindinov, M. Al-Turany, SN Alam, DSD Albuquerque, D. Aleksandrov, B Alessandro, Ian Bearden, Ante Bilandzic, Lais Ozelin de Lima PimentelChristian Alexander Bourjau, Jens Jørgen Gaardhøje, Marek Chojnacki, Freja Thoresen, Børge Svane Nielsen, bsm989 bsm989, Vojtech Pacik, Vytautas Vislavicius, You Zhou, Katarina Gajdosova, rtc312 rtc312

13 Citationer (Scopus)
33 Downloads (Pure)

Abstract

We report on the measurement of the inclusive J/ψ polarization parameters in pp collisions at a center of mass energy s=8 TeV with the ALICE detector at the LHC. The analysis is based on a data sample corresponding to an integrated luminosity of 1.23 pb- 1. J/ψ resonances are reconstructed in their di-muon decay channel in the rapidity interval 2.5 < y< 4.0 and over the transverse-momentum interval 2 < pT< 15 GeV / c. The three polarization parameters (λθ, λφ, λθ φ) are measured as a function of pT both in the helicity and Collins-Soper reference frames. The measured J/ψ polarization parameters are found to be compatible with zero within uncertainties, contrary to expectations from all available predictions. The results are compared with the measurement in pp collisions at s=7 TeV.

OriginalsprogEngelsk
Artikelnummer562
TidsskriftEuropean Physical Journal C
Vol/bind78
Udgave nummer7
Antal sider13
ISSN1434-6044
DOI
StatusUdgivet - 1 jul. 2018

Fingeraftryk

Dyk ned i forskningsemnerne om 'Measurement of the inclusive J/psi polarization at forward rapidity in pp collisions at root s=8 TeV'. Sammen danner de et unikt fingeraftryk.

Citationsformater