Anti-flow of K${}_s^0$ Mesons in 6 AGeV Au + Au Collisions

Abstract

We have measured the sideward flow of neutral strange ($K_s^0$) mesons in 6 AGeV Au + Au collisions. A prominent anti-flow signal is observed for an impact parameter range (b $\lesssim 7$ fm) which spans central and mid-central events. Since the $K_s^0$ scattering cross section is relatively small in nuclear matter, this observation suggests that the in-medium kaon vector potential plays an important role in high density nuclear matter.

5 pages, including 3 figs