Related papers: Current Status of Transverse Spin at STAR
After five years of data taking, the STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory provides precise measurements of particle production at high transverse momentum in p-p, d-Au, and Au-Au…
The eRHIC facility planned for the Brookhaven National Laboratory will allow detailed studies of the strong hadronic interactions. Among the exciting research topics discussed are the pursuit of the Color Glass Condensate, the three…
Accessing the Sivers TMD function in proton+proton collisions through the measurement of transverse single spin asymmetries (TSSAs) in Drell-Yan and weak boson production is an effective path to test the fundamental QCD prediction of the…
The STAR experiment at RHIC is a TPC-based, general purpose detector designed to obtain charged particle spectra, with an emphasis on hadrons over a large phase space. An electromagnetic calorimeter provides measurement of electrons,…
Measurements of the production of forward jets from transversely polarized proton collisions at $\sqrt{s}=500$ GeV conducted at the Relativistic Heavy Ion Collider (RHIC) are reported. Our measured jet cross section is consistent with hard…
How quarks and gluons conspire to provide the total spin of proton is a long-standing puzzle in quantum chromodynamics (QCD). The unique capability of RHIC, that can provide longitudinally polarized $p+p$ collisions at both $\sqrt{s} = 200$…
We give upper bounds for transverse double-spin asymmetries in polarized proton-proton collisions by saturating the positivity constraint for the transversity densities at a low hadronic resolution scale. We consider prompt photon, jet,…
This contribution reports on the first measurement of the longitudinal double-spin asymmetry $A_{LL}$ for the inclusive production of jets in polarized proton-proton collisions at $\sqrt{s}=200 \mathrm{GeV}$. The data were collected with…
Jet production in high energy proton-proton ($p+p$) collisions is dominated by hard QCD subprocesses such as gluon-gluon and quark-gluon scatterings. Therefore $p+p$ is an effective tool to probe the internal distribution of gluons in the…
We consider single-inclusive forward pion production in high-energy proton-proton collisions at RHIC energies. A good baseline description of the transverse momentum distributions at high rapidity is obtained within Mueller's dipole…
Longitudinally polarized $p+p$ scattering experiments provide access to gluon polarization via measurement of the double helicity asymmetry, $A_{LL}$. At the completion of the 2013 RHIC running period, a significant dataset of $\pi^{0}$s…
Large transverse single-spin asymmetries, A_{N}, have been observed in forward hadron production at RHIC. STAR has reported precision measurements of the x_{F}-p_{T} dependence of A_{N} for forward pi^0 production. Contrary to expectation,…
The transverse spin transfer, $D_{TT}$, of $\Lambda$ and $\overline{\Lambda}$ hyperons in $p$+$p$ collisions is expected to be sensitive to the $s$ and $\bar{s}$ quark transversity distributions in the proton and to the transversely…
Transverse single spin asymmetry, $A_{N}$, of very forward $\pi^{0}$ production from polarized $p + p$ collisions provides new information toward an understanding of its production mechanism. $A_{N}$ of forward $\pi^{0}$ in the…
The PHENIX experiment has measured transverse single spin asymmetry of J/$\Psi$ in polarized p+p collisions at forward rapidity at $\sqrt{s}=200$ GeV. The data were collected from year 2006 run of RHIC with average beam polarization of 56%.…
We present the STAR measurement of transverse momentum spectra at mid-rapidity for identified particles in p+p collisions at $\sqrt{s}$ = 200 GeV. These high statistics data are ideal for comparing to existing leading- and next-to-leading…
We present first measurements of forward jet production from p(pol)+p collisons at \sqrt{s}=500 GeV, including transverse single spin asymmetries. These asymmetries are expected to be sensitive to spin-correlated transverse momentum in the…
We report the transverse momentum (pT) distributions for identified charged pions, protons and anti-protons using events triggered by high deposit energy in the Barrel Electro-Magnetic Calorimeter (BEMC) from p + p collisions at psNN = 200…
The STAR experiment at RHIC has measured a variety of inclusive hadron cross sections in $p+p$ collisions at Sqrt(s) = 200 GeV. Measurements of the differential cross section for inclusive charged pion production at mid rapidity and for…
During the 2008 run the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven Nation Laboratiory (BNL), NY, provided high luminosity in both p+p and d+Au collisions at $\sqrt{s_{NN}}=200\mathrm{\,GeV}$. Electromagnetic calorimeter…