Measurement of Transverse Single-Spin Asymmetries for Dijet Production in Proton-Proton Collisions at {radical}(s)=200 GeV
- University of Illinois at Chicago, Chicago, Illinois 60607 (United States)
- Panjab University, Chandigarh 160014 (India)
- Variable Energy Cyclotron Centre, Kolkata 700064 (India)
We report the first measurement of the opening angle distribution between pairs of jets produced in high-energy collisions of transversely polarized protons. The measurement probes (Sivers) correlations between the transverse spin orientation of a proton and the transverse momentum directions of its partons. With both beams polarized, the wide pseudorapidity (-1{<=}{eta}{<=}+2) coverage for jets permits separation of Sivers functions for the valence and sea regions. The resulting asymmetries are all consistent with zero and considerably smaller than Sivers effects observed in semi-inclusive deep inelastic scattering. We discuss theoretical attempts to reconcile the new results with the sizable transverse spin effects seen in semi-inclusive deep inelastic scattering and forward hadron production in pp collisions.
- OSTI ID:
- 21024231
- Journal Information:
- Physical Review Letters, Vol. 99, Issue 14; Other Information: DOI: 10.1103/PhysRevLett.99.142003; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA). STAR Collaboration; ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
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Measurement of Transverse Single-Spin Asymmetries for Di-JetProduction in Proton-Proton Collisions at sqrt s = 200 GeV
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