Details

Autor(en) / Beteiligte

• McIlhany, K
• McKeown, RD
• Meissner, F
• Menden, FM
• Metz, A
• Meyners, N
• Mikloukho, O
• Miller, CA
• Miller, MA
• Milner, R
• Most, A
• Muccifora, V, V
• Naryshkin, Y
• Nathan, AM
• Neunreither, F
• Niczyporuk, M
• Nowak, W
• O'Neill, TG
• Openshaw, R
• Ouyang, J
• Owen, BR
• Pate, SF
• Potashov, S
• Potterveld, DH
• Rakness, G
• Redwine, R

Titel

Measurement of the spin asymmetry in the photoproduction of pairs of high- p(T) hadrons at HERMES

Ist Teil von

• Physical review letters, 2000-03, Vol.84 (12), p.2584-2588

Ort / Verlag

United States

Erscheinungsjahr

2000

Quelle

PROLA - Physical Review Online Archive

Beschreibungen/Notizen

• We present a measurement of the longitudinal spin asymmetry A(||) in photoproduction of pairs of hadrons with high transverse momentum p(T). Data were accumulated by the HERMES experiment using a 27.5 GeV polarized positron beam and a polarized hydrogen target internal to the HERA storage ring. For h(+)h(-) pairs with p(h(1))(T)>1.5 GeV/c and p(h(2))(T)>1.0 GeV/c, the measured asymmetry is A(||) = -0. 28+/-0.12(stat)+/-0.02(syst). This negative value is in contrast to the positive asymmetries typically measured in deep inelastic scattering from protons, and is interpreted to arise from a positive gluon polarization.