Related papers: Current Status of Transverse Spin at STAR
The STAR experiment at the Relativistic Heavy Ion Collider RHIC studies the new state of matter produced in relativistic heavy ion collisions and the spin structure of the nucleon in collisions of polarized protons. In order to improve the…
The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) performs studies of diffractive processes with the focus on the exclusive production of particles in central range of rapidity. In 2015 STAR collected 18 pb$^{-1}$ of data in…
The high centre-of-mass energy of 200 GeV available at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven opens up the hard scattering regime in heavy-ion collisions. Particles at large transverse momentum originate from the early…
A significant sample of $p^{\uparrow}p\to p\pi^0 X$ events has been observed at STAR in $\sqrt{s}=200$ GeV transversely polarized $pp$ collisions, where an isolated $\pi^0$ is detected in the forward pseudorapidity range $2.65<\eta<3.9$…
In the 2001-2002 running period of the Relativistic Heavy Ion Collider (RHIC), transversely polarized protons were accelerated to 100 GeV for the first time, with collisions at sqrt{s} = 200 GeV. We present results from this run for single…
The production of $W^\pm$ bosons in longitudinally polarized $p+p$ collisions at RHIC provides a direct probe for the spin-flavor structure of the proton through the parity-violating single-spin asymmetry, $A_L$. At STAR, the leptonic decay…
We present analysis of J/$\psi$ production over the range $-1.0 < \eta < 4.2$ in p+p and d+Au collisions using di-electron data taken during the 2008 run with the STAR experiment at Brookhaven National Laboratory. STAR's unique forward…
The differential cross section and spin asymmetries for neutral pions produced within the intermediate pseudorapidity range 0.8 < {\eta} < 2.0 in polarized proton-proton collisions at sqrt{s} = 200 GeV are presented. Neutral pions were…
In the high-energy $p+p$ collisions, the transverse single spin asymmetry for very forward neutron production has been interpreted by an interference between $\pi$ (spin flip) and $a_1$ (spin non-flip) exchange with a non-zero phase shift.…
The production of $W^\pm$ bosons in longitudinally polarized proton-proton collisions at RHIC provides a direct probe for the spin-flavor structure of the proton through the parity-violating single-spin asymmetry, $A_L$. At STAR, the…
Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in $p^\uparrow+p$ collisions at…
The STAR Collaboration reports a measurement of the transverse single-spin asymmetries, $A_{N}$, for neutral pions produced in polarized proton collisions with protons ($pp$), with aluminum nuclei ($p\rm{Al}$) and with gold nuclei…
Highlights of news from Brookhaven National Laboratory (BNL) and results from the Relativistic Heavy Ion Collider (RHIC) in the period July 2015-2016 are presented. Transverse single spin asymmetries from polarized p+p collisions are…
The sPHENIX experiment is a next-generation collider detector at the Relativistic Heavy Ion Collider (RHIC) designed for rare jet and heavy-flavor probes of Au + Au, $p$ + Au, and polarized $p+p$ collisions. The experiment includes a large…
During the 2008 run RHIC provided high luminosity in both p+p and d+Au collisions at $\sqrt{s_{NN}}= 200$ GeV. Electromagnetic calorimeter acceptance in STAR was enhanced by the new Forward Meson Spectrometer (FMS), and is now almost…
The Polarized Atomic Hydrogen Gas Jet Target polarimeter is employed by the Relativistic Heavy Ion Collider (RHIC) to measure the absolute polarization of each colliding proton beam. Polarimeter detectors and data acquisition were upgraded…
The measurement of transverse single spin asymmetries ($A_N$) provides insight into the structure of the nucleon. Several mechanisms have been proposed that attempt to explain $A_N$ based on QCD, and additional measurements of $A_N$ for…
The gluon polarization contribution to the proton spin is an integral part to solve the longstanding proton spin puzzle. At the Relativistic Heavy Ion Collider (RHIC), the STAR experiment has measured jets produced in mid-pseudo-rapidity,…
Preliminary results are presented on high-pT inclusive neutral pion production in d+Au collisions at sqrt(sNN) = 200 GeV in the pseudo-rapidity range 0 < eta < 1. Photons from the decay pi0->gamma,gamma are detected in the Barrel…
We report the first measurements of transverse single-spin asymmetries for inclusive jet and jet + $\pi^{\pm}$ production at midrapidity from transversely polarized proton-proton collisions at $\sqrt{s} = 500$ GeV. The data were collected…