核实验
The BRAHMS experiment at RHIC has the capability to measure the transverse spin asymmetries in polarized pp induced pion production at RHIC. The first results from the short run-4 show a signaificant asymmetry for pi-plus and pi-minus at…
The rapidity dependence of the nuclear modification factor in d-Au collaisions at sqrt(s) = 200 GeV at RHIC is discussed.
The NPDGamma collaboration has constructed and commissioned an apparatus to determine the size of the pion-nucleon coupling constant in the parity non conserving pion exchange weak potential for N-N interactions. This coupling constant is…
We report here the BRAHMS measurements of particle production in d+Au and p+p collisions at RHIC. The results presented here are compared to previous p+A measurements at lower energies in fixed target mode. Some preliminary results on…
Photoproduction can be studied at hadron colliders by using the virtual photons associated with the hadron beams. The LHC will reach photonucleon energies 10 times higher than that available elsewhere. These reactions are already being…
A near-threshold 4He(g,n) cross-section measurement has been performed at MAX-lab. Tagged photons from 23 < Eg < 42 MeV were directed toward a liquid 4He target, and neutrons were detected by time-of-flight in two liquid-scintillator…
We present centrality dependent charged hadron yields at several pseudorapidities from Au+Au collisions at Sqrt(s)=200GeV measured with BRAHMS spectrometers. Nuclear modification factors RAA and RCP for charged hadrons at forward angles in…
A nontrivial space-time structure of the hot system created at RHIC is the defining aspect of the physics of relativistic heavy ion collisions. Femtoscopy through pion intensity interferometry provides direct access to the dynamic geometric…
Measurements of identified particle production with the PHENIX experiment at RHIC have reached a mature state, where a multitude of nuclear systems at different colliding energies have been studied. The discovery configurations of…
A brief review of BRAHMS measurements of bulk particle production in RHIC Au+Au collisions at $\sqrt{s_{NN}}=200GeV$ is presented, together with some discussion of baryon number transport. Intermediate $p_{T}$ measurements in different…
Results on direct photon measurements from the PHENIX experiment at RHIC are presented. The direct photon yields for $p_T>$6 GeV/$c$ as a function of centrality in Au-Au collisions at $\sqrt{s_{NN}}$=200 GeV are found to be consistent with…
The photoproduction of omega mesons on nuclei has been investigated using the Crystal Barrel/TAPS experiment at the ELSA tagged photon facility in Bonn. The aim is to study possible in-medium modifications of the omega meson via the…
STAR observes a complex picture of RHIC collisions where correlation effects of different origins -- initial state geometry, semi-hard scattering, hadronization, as well as final state interactions such as quantum intensity interference --…
Direct photons are an important tool for the detection of the quark-gluon plasma in ultra-relativistic nucleus-nucleus collisions. Direct-photon measurements were made in Pb+Pb collisions at sqrt{s_NN}=17.2 GeV and in Au+Au collisions at…
The resonance production of $\Delta$, K(892), $\Sigma$(1385), $\Lambda$(1520) and $\phi$ from elementary p+p and Au+Au collisions at $\sqrt{s_{\rm NN}} = $ 200 GeV from the STAR experiment at RHIC is presented. Yields and spectra are…
The NA60 experiment at the CERN SPS studies dimuon production in proton-nucleus and nucleus-nucleus collisions. The combined information from a novel vertex telescope made of radiation-tolerant silicon pixel detectors and from the muon…
Measurements are reported of the production of high energy pi^0 mesons at large pseudorapidity, coincident with charged hadrons at mid-rapidity, for proton+proton and deuteron+gold collisions at sqrt{s_{NN}}=200 GeV. The p+p cross section…
In this paper, preliminary results are presented on high-$p_T$ inclusive neutral pion measurements in d-Au collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV in the pseudo-rapidity range $0<\eta<1$. The photons of the decay $pi^0\to\gamma\gamma$…
Typical experimental measurements do not separate the contributions of Sigma state decays from (anti)Lambda yields. An ongoing analysis in STAR is resolving the contribution from excited Sigma states, but the primary contribution comes from…
Using the forward time projection chambers of the STAR experiment at the Brookhaven Relativistic Heavy Ion Collider we measure the centrality dependent Lambda and Anti-Lambda yields and inverse slope parameters in d+Au collisions at forward…