Cross Section and Double Helicity Asymmetry for Eta Mesons and Their Comparison to Neutral Pion Production in p+p Collisions at s = 200 GeV

Journal Article · Sat Jan 01 00:00:00 EST 2011 · Physical Review D

DOI:https://doi.org/10.1103/PhysRevD.83.032001· OSTI ID:1006463

Adare, A ^[1]; Awes, Terry C ^[2]; Cianciolo, Vince ^[2]; Efremenko, Yuri ^[3]; Enokizono, Akitomo ^[4]; Read, Jr, Kenneth F ^[2]; Silvermyr, David O ^[2]; Sorensen, Soren P ^[5]; Stankus, Paul W ^[2]

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1. University of Colorado, Boulder
2. ORNL
3. University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)
4. Oak Ridge National Laboratory (ORNL)
5. University of Tennessee, Knoxville (UTK)

Measurements of double-helicity asymmetries in inclusive hadron production in polarized p+p collisions are sensitive to helicity-dependent parton distribution functions, in particular to the gluon helicity distribution, {Delta}g. This study focuses on the extraction of hte double-helicity asymmetry in {eta} production (p+p{yields}{eta}+X), the {eta} cross section, and the {eta}/{pi}{sup 0} cross section ratio. The cross section and ratio measurements provide essential input for the extraction of fragmentation functions that are needed to acess the helicity-dependent parton distribution functions.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1006463
• Journal Information: Physical Review D, Vol. 83, Issue 3; ISSN 1550--7998
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
COLLISIONS
CROSS SECTIONS
DISTRIBUTION
DISTRIBUTION FUNCTIONS
ETA MESONS
EXTRACTION
FRAGMENTATION
FUNCTIONS
GLUONS
HADRONS
HELICITY
PIONS
PRODUCTION