paper

Multi-strange baryon elliptic flow in Au+Au collisions at sqrt(s_NN)= 200 GeV

arXiv:nucl-ex/0504022 · doi:10.1103/PhysRevLett.95.122301

Abstract

We report on the first measurement of elliptic flow $v_{2} (p_{T})$ of multi-strange baryons $I^ + X i ˉ$ and $I^c ◯ + O m e g a ˉ inh e a v y - i o n co l l i s i o n s . I nminim u mbia s A u + A u co l l i s i o n s a t s q r t (s_{N} N) = 200 G e V, a s i g ni f i c an t am o u n t o f e l l i pt i c f l o w, co m p a r ab l e t oo t h er n o n - s t r an g e ba r y o n s, i so b ser v e df or m u l t i - s t r an g e ba r y o n s w hi c ha r ee x p ec t e d t o b e p a r t i c u l a r l y se n s i t i v e t o t h e d y nami cso f t h e p a r t o ni cs t a g eo f h e a v y - i o n co l l i s i o n s . T h e$ p_T $d e p e n d e n ceo f$ v_2$ of the multi-strange baryons confirms the number of constituent quark scaling previously observed for lighter hadrons. These results support the idea that a substantial fraction of the observed collective motion is developed at the early partonic stage in ultra-relativistic nuclear collisions at RHIC.

6 pages, 3 figures, submitted to PRL