Priyanka Roy Chowdhury
supervisor: Daniel Kikola
The main goal of the project is to measure the femtoscopic correlations of `D^0` mesons with charged hadrons (pion, kaon, proton) in Au-Au collisions at center of mass energy per nucleon pair `√SNN = 200` GeV in the STAR experiment at RHIC (Relativistic Heavy Ion Collider). The project is related to the studies of Quark Gluon Plasma (QGP) properties with a measurement of the `J/ψ` (cc) production. In heavy ion collision, suppression in `J/ψ` production is a proof of presence of QGP state. On the other hand, there’s a possibility of production of secondary `J/ψ` from the produced charm quarks in QGP state. To study the secondary `J/ψ` production, we need to calculate the correlation function between charm and anti-charm quarks but that is difficult.
We propose to measure the effective size of the source `r_0` from which correlated pairs of D-mesons and hadrons are emitted. From `r_0` we can calculate the effective volume `V_(eff)` of the source. For a strong correlation between c/c (from `D^0` candidates) and hadrons (charm or any other quarks), source size (where c/c quarks interact with other partons in the QGP) will be small compared to the size of the fireball in the QGP and vice-versa. By fitting the analytical result into a suitable model, a conclusion can be drawn for the c-c correlation which is the determinant factor for the secondary production of J/ψ meson in the QGP. Using Au-Au run 2014 and 2016 data, we calculated the correlation function for `D^0-`(π/k/p) pairs and applied corrections.