Speaker
Description
In recent years, the PHENIX experiment has observed collectivity in small collision systems. This behavior resembles what is seen in large systems where quark-gluon plasma (QGP) is produced. However, whether QGP actually forms in small systems is still being debated.
This work presents measurements of the neutral pion elliptic flow ($v_2$) coefficients as a function of $p_T$ for different centrality classes in p+Au, $^3$He+Au, and p+Al collisions at 200 GeV using the event plane method. In central collisions (0-5%) for $p_T$ from 1 to 3 GeV/c, the $v_2$ values in $^3$He+Au exceed those in p+Au and p+Al. Moreover, in all three collision systems, $v_2$ values rise from central to peripheral collisions, with larger values observed in the 40-60% centrality class.
