Speaker
Ms
Neha Shah
(University of California Los Angeles)
Description
The production of large number of multi-strange hyperons per central nucleus-nucleus collision at RHIC allows us to study hyperon-hyperon interactions through measurement of particle correlations and search for exotic particles like dihyperons. In 1977 Jaffe[1] predicted a six quark state, $H_{0}$-dibaryon, with hypercharge (Y) = 0 and Strangeness (S) = -2 to be stable against strong decay, but not to weak decay. It has been proposed that the $H_{0}$ would appear as a bump in the $\Lambda-\Lambda$ invariant mass spectra if the $H_{0}$ is a resonance state, or it would lead to a depletion of the $\Lambda-\Lambda$ correlation near the threshold if the $H_{0}$ is weakly bound, which can be used to probe whether there is a stable $H_{0}$ or resonance. Considerable experimental efforts have been devoted to search for $H_{0}$. However there is no conclusive experimental evidence for a bound $H_{0}$. In addition to $H_{0}$, many other dihyperon states have been predicted thoeretically. However, very few measurements are available due to low multiplicity of hyperon production in early nuclear collisions.
Recently STAR has collected unprecedented high statistics data for Au+Au collision at RHIC, which provides a unique opportunity to look for the exotic particles and hyperon-hyperon correlations. In this talk, we will present the measurement of $\Lambda-\Lambda$ correlations for $\sqrt{s_{NN}}$ = 39-200 GeV in Au+Au collisions using the STAR experiment at RHIC. In addition to that, we will also present measurements of $\Lambda-\bar\Lambda$, $\Lambda-\Xi^{-}$ correlations for $\sqrt{s_{NN}}$ = 200 GeV in Au+Au collisions.
[1] R. L. Jaffe,Phys. Rev. Lett. 38,195(1977).
Primary author
Ms
Neha Shah
(University of California Los Angeles)