The first achievement of longitudinal spin polarization in a high energy electron storage ring

Barber, D. P.; Böge, M.; Bremer, Hartmut; Brinkmann, R.; Brückner, W.; Düren, M.; Gianfelice-Wendt, E.; Großhauser, C.; Kaiser, H.; Klanner, R.; Lomperski, M.; Meyer, G. De; Meyners, N.; Oelwein, P.; Ripken, G.; Rith, Klaus; Schmidt, G.; Steffens, E.; Wander, W.; Wümpelmann, W.; Zapfe, K.; Zetsche, Frank

doi:10.1016/0370-2693(94)01465-o

Cited by 66 publications

(20 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The data were recorded during the 1996 and 1997 running periods of the HERMES experiment using both unpolarized and longitudinally nuclear-polarized hydrogen internal gas targets [10] in the 27.6 GeV HERA polarized positron storage ring at DESY. Longitudinal beam polarization is obtained by using spin rotators [11] located upstream and downstream of the HERMES experiment. The scattered positrons and associated pions are detected by the HERMES spectrometer [12] in the polar angle range 0.04 , u , 0.22 rad.…”

Section: (Received 28 October 1999)mentioning

confidence: 99%

Evidence for a Single-Spin Azimuthal Asymmetry in Semi-inclusive Pion Electroproduction

Airapetian¹,

Amarian²,

Aschenauer³

et al. 2000

Phys. Rev. Lett.

Self Cite

285

197

View full text Add to dashboard Cite

Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal angle φ of the pion relative to the lepton scattering plane was formed for π+ electroproduction on a longitudinally polarized hydrogen target. The corresponding analyzing power in the sinφ moment of the cross section is 0.022+/-0.005+/-0.003. This result can be interpreted as the effect of terms in the cross section involving chiral-odd spin distribution functions in combination with a chiral-odd fragmentation function that is sensitive to the transverse polarization of the fragmenting quark

show abstract

Section: (Received 28 October 1999)mentioning

confidence: 99%

Evidence for a Single-Spin Azimuthal Asymmetry in Semi-inclusive Pion Electroproduction

Airapetian¹,

Amarian²,

Aschenauer³

et al. 2000

Phys. Rev. Lett.

Self Cite

285

197

View full text Add to dashboard Cite

show abstract

“…(2) are other interference terms that are suppressed by O ͑1͞Q͒, but they involve other f moments. The data presented here were recorded during the 1996 and 1997 running periods of the HERMES experiment using the 27.6-GeV HERA longitudinally polarized positron beam at DESY [10]. The beam polarization was continuously measured by Compton backscattering and had an average value of 0.55 with a fractional uncertainty of 3.8% [11,12].…”

mentioning

confidence: 99%

Measurement of the Beam-Spin Azimuthal Asymmetry Associated with Deeply-Virtual Compton Scattering

Airapetian¹,

Акопов²,

Akopov³

et al. 2001

Phys. Rev. Lett.

Self Cite

285

View full text Add to dashboard Cite

“…The required longitudinal polarization direction at the HERMES experiment is obtained using spin rotators located upstream and downstream of the experiment [17]. The beam polarization is measured continuously using Compton backscattering of circularly polarized laser light [18,19].…”

mentioning

confidence: 99%

Flavor decomposition of the polarized quark distributions in the nucleon from inclusive and semi-inclusive deep-inelastic scattering

Ackerstaff¹,

Airapetian²,

Акопов³

et al. 1999

Physics Letters B

Self Cite

160

View full text Add to dashboard Cite

Spin asymmetries of semi-inclusive cross sections for the production of positively and negatively charged hadrons have been measured in deep-inelastic scattering of polarized positrons on polarized hydrogen and He-3 targets, in the kinematic range 0.023 < x < 0.6 and 1 GeV2 < Q(2) < 10 GeV2. Polarized quark distributions are extracted as a function of x for up (u + (u) over bar) and down (d + (d) over bar) flavors. The up quark polarization is positive and the down quark polarization is negative in the measured range. The polarization of the sea is compatible with zero. The first moments of the polarized quark distributions are presented. The isospin non-singlet combination dq, is consistent with the prediction based on the Bjorken sum rule. The moments of the polarized quark distributions are compared to predictions based on SU(3)(f) flavor symmetry and to a prediction from lattice QCD. (C) 1999 Published by Elsevier Science B.V. All rights reserved

show abstract

The first achievement of longitudinal spin polarization in a high energy electron storage ring

Cited by 66 publications

References 9 publications

Evidence for a Single-Spin Azimuthal Asymmetry in Semi-inclusive Pion Electroproduction

Evidence for a Single-Spin Azimuthal Asymmetry in Semi-inclusive Pion Electroproduction

Measurement of the Beam-Spin Azimuthal Asymmetry Associated with Deeply-Virtual Compton Scattering

Flavor decomposition of the polarized quark distributions in the nucleon from inclusive and semi-inclusive deep-inelastic scattering

Contact Info

Product

Resources

About