22-27 September 2016
East Lake International Conference Center
Asia/Chongqing timezone
<a href="http://hp2016.ccnu.edu.cn">http://hp2016.ccnu.edu.cn</a>

Relative Yields and Nuclear Modification of Psi' to J/Psi mesons in p+p, p(3He)+A Collisions at sqrt(s_NN) = 200 GeV, measured in PHENIX

25 Sep 2016, 12:00
Jing-Zhou Hall (East Lake International Conference Center)

Jing-Zhou Hall

East Lake International Conference Center

Donghu Road 142, Wuchang District, Wuhan, Hubei, China


Axel Drees (Stony Brook University)


The PHENIX collaboration has measured the ratio of the Psi(2s) to the
Psi(1s) cross section in p+p and p(3He)+A collisions at forward and
backward rapidity. We find that in p+p collisions, the data are
consistent with expectations from a modified color evaporation model
of quarkonia formation. In p(3He)+A collisions, in the p(3He)-going
direction, within uncertainties there is an equivalent nuclear
modification of both Psi states. However, in the A-going direction,
the nuclear modification factor of the weaker bound Psi(2s) is a
factor of 2 less than that of the Psi(1s). Since these states are not
fully formed until after they exit the nucleus, interactions between
the fully formed charmonia and co-moving hadrons may be responsible
for this effect, consistent with the higher particle density in the
A-going direction relative to the p(3He)-going direction. This
mechanism may compete with color screening in a deconfined plasma in
A+A collisions to produce sequential suppression of excited quarkonia

Presentation type Oral

Primary author

Axel Drees (Stony Brook University)

Presentation Materials