Transverse single-spin asymmetries to probe the transverse-spin structure of the proton have been measured for neutral pions and nonidentified charged hadrons from polarized proton-proton collisions at midrapidity and square root(s) = 200 GeV. The data cover a transverse momentum (pT) range 1.0-5.0 GeV/c for neutral pions and 0.5-5.0 GeV/c for charged hadrons, at a Feynman-x value of approximately zero. The asymmetries seen in this previously unexplored kinematic region are consistent with zero within errors of a few percent. In addition, the inclusive charged hadron cross section at midrapidity from 0.5 < pT < 7.0 GeV/c is presented and compared to next-to-leading order perturbative QCD (pQCD) calculations. Successful description of the unpolarized cross section above approximately 2 GeV/c suggests that pQCD is applicable in the interpretation of the asymmetry results in the relevant kinematic range.

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevLett.95.202001DOI Listing

Publication Analysis

Top Keywords

neutral pions
12
charged hadrons
12
transverse single-spin
8
single-spin asymmetries
8
hadrons polarized
8
square roots
8
roots 200
8
200 gev
8
measurement transverse
4
asymmetries midrapidity
4

Similar Publications

Dark-Sector Search via Pion-Produced η and η^{'} Mesons Decaying Invisibly in the NA64h Detector.

Phys Rev Lett

September 2024

Authors affiliated with an international laboratory covered by a cooperation agreement with CERN.

We present the first results from a proof-of-concept search for dark sectors via invisible decays of pseudoscalar η and η^{'} mesons in the NA64h experiment at the CERN SPS. Our novel technique uses the charge-exchange reaction of 50 GeV π^{-} on nuclei of an active target as the source of neutral mesons. The η,η^{'}→invisible events would exhibit themselves via a striking signature-the complete disappearance of the incoming beam energy in the detector.

View Article and Find Full Text PDF
Article Synopsis
  • The Letter reports the most accurate measurement so far of the matter-antimatter imbalance during Pb-Pb collisions at a high energy level of 5.02 TeV.
  • It utilizes the Statistical Hadronization framework to determine precise values for the electric charge and baryon chemical potentials, μ_{Q} and μ_{B}.
  • The analysis of antiparticle-to-particle yield ratios shows that the collisions create a system that is generally baryon-free and electrically neutral at midrapidity.
View Article and Find Full Text PDF

We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.

View Article and Find Full Text PDF

We present the first comprehensive tests of the universality of the light leptons in the angular distributions of semileptonic B^{0}-meson decays to charged spin-1 charmed mesons. We measure five angular-asymmetry observables as functions of the decay recoil that are sensitive to lepton-universality-violating contributions. We use events where one neutral B is fully reconstructed in ϒ(4S)→BB[over ¯] decays in data corresponding to 189  fb^{-1} integrated luminosity from electron-positron collisions collected with the Belle II detector.

View Article and Find Full Text PDF

The nuclear modification factor of neutral pions is measured in proton-lead collisions collected at a center-of-mass energy per nucleon of 8.16 TeV with the LHCb detector. The π^{0} production cross section is measured differentially in transverse momentum (p_{T}) for 1.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!