This corrects the article DOI: 10.1103/PhysRevLett.92.062301.

This corrects the article DOI: 10.1103/PhysRevLett.89.132301.

The system created in non-central relativistic nucleus-nucleus collisions possesses large orbital angular momentum. Due to spin-orbit coupling, particles produced in such a system could become globally polarized along the direction of the system angular momentum. We present the results of Lambda and anti-Lambda hyperon global polarization measurements in Au+Au collisions at sqrts_NN=62.4 GeV and 200 GeV performed with the STAR detector at RHIC. The observed global polarization of Lambda and anti-Lambda hyperons in the STAR acceptance is consistent with zero within the precision of the measurements. The obtained upper limit, |P_Lambda,anti-Lambda| <= 0.02, is compared to the theoretical values discussed recently in the literature.

Analyzing DISTO data of pp → pΛK + at T p = 2.50 and 2.85GeV to populate a previously reported X(2265) -resonance with M x = 2267 MeV/c2 and Γ x = 118 MeV at 2.85GeV, we found that the yield of X(2265) at 2.50GeV is much less than that at 2.85GeV (less than 10%), though it is expected from a kinematical consideration to be produced as much as 33% of that at 2.85GeV. The small population of X(2265) at 2.50GeV is consistent with the very weak production of Γ(1405) at the same incident energy toward its production threshold, thus indicating that Γ(1405) plays an important role as a doorway state for the formation of X(2265).

We have analyzed data of the DISTO experiment on the exclusive pp rightarrow p Lambda K+ reaction at 2.50 GeV and 2.85 GeV incident energy and found that a previously reported X = K-pp rightarrow p Lambda with M_X = 2267 MeV/c2 and a width Gamma_X = 118$ MeV, in the reaction channel pp rightarrow K+ + X at 2.85 GeV, is not populated at 2.50 GeV, though it is kinematically allowed and is expected to be produced as much as 50 % of that at 2.85 GeV. The absence of X at 2.50 GeV is in line with the very weak production of Lambda (1405) at 2.50 GeV toward its production threshold, thus giving a direct evidence that Lambda (1405) is the doorway state for the formation of K-pp with a high p-Lambda(1405) sticking probability at 2.85 GeV.

Analyzing DISTO data of $pp -> p Lambda K^+$ at $T_p = 2.50$ and 2.85 GeV to populate a previously reported X(2265) resonance with $M_X = 2267$ MeV/$c^2$ and $Gamma_X = 118$ MeV at 2.85 GeV, we found that the production of X(2265) at 2.50 GeV is much less than that at 2.85 GeV (less than 10%), though it is expected from a kinematical consideration to be produced as much as 33% of that at 2.85 GeV. The small population of X(2265) at 2.50 GeV is consistent with the very weak production of Lambda (1405) at the same incident energy toward its production threshold, thus indicating that Lambda (1405) plays an important role as a doorway state for the formation of X(2265).

Received 4 February 2011DOI:https://doi.org/10.1103/PhysRevLett.106.159902© 2011 American Physical Society

We have analyzed data of the DISTO experiment on the exclusive pp -> p Lambda K+ reaction at 2.85 GeV to search for a strongly bound compact K-pp (= X) state to be formed in the pp -> K+ + X reaction. The observed spectra of the K+ missing-mass and the p Lambda invariant-mass with high transverse momenta of p and K+ revealed a broad distinct peak with a mass M_X = 2265 +- 2 (stat) +- 5 (syst) MeV/c2 and a width Gamma_X = 118 +- 8 (stat) +- 10 (syst) MeV.

The data from the DISTO Collaboration on the exclusive pp -> pK(+)Lambda production acquired at T-p = 2.85 GeV have been re-analysed in order to search for a deeply bound K(-)pp( X) state, to be formed in the binary process pp -> K+X. The preliminary spectra of the Delta MK+, missing-mass and of the M-p Lambda invariant-mass show, for large transverse-momenta of protons and kaons, a distinct broad peak with a mass M-X = 2265 +/- 2 MeV/c(2) and a width Gamma(X) = 118 +/- 8 MeV/c(2).

Charged-particle spectra associated with direct photon ($\gamma_{dir} $) and $\pi^0$ are measured in $p$+$p$ and Au+Au collisions at center-of-mass energy $\sqrt{s_{_{NN}}}=200$ GeV with the STAR detector at RHIC. A hower-shape analysis is used to partially discriminate between $\gamma_{dir}$ and $\pi^0$. Assuming no associated charged particles in the $\gamma_{dir}$ direction (near side) and small contribution from fragmentation photons ($\gamma_{frag}$), the associated charged-particle yields opposite to $\gamma_{dir}$ (away side) are extracted. At mid-rapidity ($|\eta|<0.9$) in central Au+Au collisions, charged-particle yields associated with $\gamma_{dir}$ and $\pi^0$ at high transverse momentum ($8< p_{T}^{trig}<16$ GeV/$c$) are suppressed by a factor of 3-5 compared with $p$ + $p$ collisions. The observed suppression of the associated charged particles, in the kinematic range $|\eta|<1$ and $3< p_{T}^{assoc} < 16$ GeV/$c$, is similar for $\gamma_{dir}$ and $\pi^0$, and independent of the $\gamma_{dir}$ energy within uncertainties. These measurements indicate that the parton energy loss, in the covered kinematic range, is insensitive to the parton path length.

We have analyzed data of the DISTO experiment on the exclusive pp --> pLambdaK+ reaction at 2.85 GeV to search for a strongly bound compact K- pp(approximately = X) state to be formed in the pp --> K+ + X reaction. The observed spectra of the K+ missing mass and the pLambda invariant-mass with high transverse momenta of p and K+ revealed a broad distinct peak of 26-sigma confidence with a mass M(X)=2267+/-3(stat)+/-5(syst) MeV/c2 and a width Gamma(X)=118+/-8(stat)+/-10(syst) MeV. The enormously large cross section indicates formation of a compact K- pp with a large binding energy of B(K)=103 MeV, which can be a possible gateway toward cold and dense kaonic nuclear matter.

We present results on the system size dependence of high transverse momentum di-hadron correlations at sNN=200GeV as measured by STAR at RHIC. Measurements in d+Au, Cu+Cu and Au+Au collisions reveal similar jet-like near-side correlation yields (correlations at small angular separation – Δϕ∼0, Δη∼0) for all systems and centralities. Previous measurements have shown that the away-side (Δϕ∼π) yield is suppressed in heavy-ion collisions. We present measurements of the away-side suppression as a function of transverse momentum and centrality in Cu+Cu and Au+Au collisions. The suppression is found to be similar in Cu+Cu and Au+Au collisions at a similar number of participants. The results are compared to theoretical calculations based on the parton quenching model and the modified fragmentation model. The observed differences between data and theory indicate that the correlated yields presented here will further constrain dynamic energy loss models and provide information about the dynamic density profile in heavy-ion collisions.