Searching for J/psi collective flow in pp collisions at the LHC

Quark gluon plasma (QGP) is an extremely hot, dense state of matter in which the quarks and gluons, normally confined to colorless hadrons, are temporarily deconfined. The QGP can be formed in high energy nuclear collisions such as PbPb, and possibly in smaller systems such as pPb collisions. The question of how small a system can form a droplet of QGP is one of much experimental and theoretical interest. One way to probe the QGP is by measuring anisotropic flow, which manifests in long-range correlations between particles as the QGP droplet expands with anisotropic pressure gradients. It is expected that heavier particles will have little or no flow. The CMS collaboration at CERN has measured the flow of open and closed charm mesons and compared the values to those of lighter hadrons. They found the flow of J/psi mesons to be similar to that of D0 mesons in both high multiplicity pPb and PbPb collisions. While the open heavy flavor mesons may acquire flow because they contain light quarks that equilibrate in the medium, for J/psi to flow the charm quarks need to be equilibrated too, which is more difficult, especially in small systems. These observations may signal that mechanisms other than QGP formation and pressure gradients are responsible for the azimuthal anisotropy in J/psi production. To provide insight into this puzzle I aim to measure the J/psi azimuthal distributions and look for flow in pp collisions using the CMS detector. This work is in the beginning stages, so I plan to present the motivation for the measurement and performance plots demonstrating the CMS detector's ability to measure dimuon candidates for J/psi in pp collisions and their azimuthal anisotropy.