J/$\psi$ polarization measurement in p+p collisions at $\sqrt{s}$ = 500 GeV in STAR

20 May 2014, 16:30
spectrum (darmstadtium)



Board: F-55
Poster Open Heavy Flavour and Quarkonia Poster session


Barbara Trzeciak (Czech Technical University in Prague)


Experimental data on the J/$\psi$ cross section in $p$+$p$ collisions can be described relatively well by many models that are currently available on the market. These models have different predictions regarding the J/$\psi$ polarization. Therefore measurements of the J/$\psi$ polarization may allow discriminating among the models and provide new insight into on the J/$\psi$ production mechanism. The previous STAR J/$\psi$ polarization analysis was performed only for the polarization parameter $\lambda_{\theta}$ and in one reference frame due to limited statistics. Proton-proton data taken in year 2011 at $\sqrt{s}$ = 500 GeV with integrated luminosity of 22 $pb^{-1}$ will allow us to extract the full information about the dielectron decay angular distribution of the J/$\psi$ in different reference frames (helicity, Collins-Soper and Gottfried-Jackson frames). In this presentation, the status of the J/$\psi$ polarization measurement at mid-rapidity at $\sqrt{s}$ = 500 GeV in $p$+$p$ collisions in the STAR experiment will be shown.
On behalf of collaboration: STAR

Primary author

Barbara Trzeciak (Czech Technical University in Prague)

Presentation Materials