Participants: 21

Introduction (Raphael):

Two new postdoc positions in HonexComb have just been announced:


Discussion: no comments/questions

Polarisation and charmonia production studies (Jacek Biernat):


Pasquale Di Nezza: Can a solenoidal magnetic field impact the polarisation? There were studies on this topic indicating that there might be an effect from the magnetic field.

Andrzej Kupsc: It should be a tiny effect based on BES which even can be corrected for using vertex information.

Giulia Manca: The LHCb Collaboration has measured production and polarisation of J/psi, Psi',Upsilon in pp collisions at various energies. Results are hard to interpret. No good model was found which would explain cross sections and polarisation at the same time.

JB: Lack of hydrodynamic approach to the topic which would address how medium affects the anisotropy. The polarisation is sensitive to the initial conditions.

GM: Can the polarisation be studies in proton-lead collisions?

GM: Yes, there is an interesting result from HERAB (page 16). This should be tried at the LHC.

Helena Santos: results on pages 18-19 are important to make them separately for prompt and non-prompt production. The production mechanism proved to play a role in the comparisons.

GM: LHCb is for prompt, while ALICE is inclusive.

JB: ALICE can try separating out prompt vs non-prompt components in pp collisions.   In HIC it might be very difficult.

Raphael: It would be great to review existing measurements in this topic from the LHC.

GM: One could concentrate on Upsilon which should be clean with Upsilon(3S) being the cleanest probe.

JB: Statistic might be an issue for Upsilon and in particular Upsilon(3S).