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

Ackerstaff, K.; Airapetian, A.; Акопов, Н.; Akushevich, Igor; Amarian, M.; Aschenauer, E. C.; Avakian, H.; Avakian, R.; Avetissian, A.; Bains, B.; Barrow, S.; Baumgarten, C.; Beckmann, M.; Belostotski, S.; Belz, Andrea; Benisch, T.; Bernreuther, S.; Bianchi, N.; Blanchard, S.; Blouw, J.; Böttcher, H.; Borissov, A.; Brack, J.; Bray, B.; Brauksiepe, S.; Braun, B.; Brons, S.; Brückner, W.; Brüll, A.; Bruins, E. E. W.; Bulten, H.; Cadman, R. V.; Capitani, G. P.; Carter, P.; Chumney, P.; Cisbani, E.; Court, G.R.; Dalpiaz, P.; Лео, Р. Де; Delheij, P. P. J.; Sanctis, E. De; Schepper, D. De; Devitsin, E.; Huberts, P.K.A. de Witt; Nezza, P. Di; Düren, M.; Dvoredsky, A.; Ely, James H.; Elbakian, G.; Emerson, Joseph; Fantoni, A.; Fechtchenko, A.; Ferstl, M.; Fick, D.; Fiedler, K.; Filippone, B. W.; Fischer, H.; Fortune, H. T.; Fox, B. D.; Frabetti, S.; Franz, J.; Frullani, S.; Funk, M.-A.; Gagunashvili, N.; Galumian, P.; H, Gao; Gärber, Y.; Garibaldi, F.; Gavrilov, G.; Geiger, P.; Gharibyan, V.; Golendukhin, A.; Graw, G.; Grebeniouk, O.; Green, P.W.; Greeniaus, L.G.; Großhauser, C.; Guidal, M.; Gute, A.; Gyurjyan, V.; Haas, J.; Haeberli, W.; Hansen, J. O.; Hasch, D.; Häusser, O.; Henderson, R.; Heinsius, F. H.; Henkes, T.; Henoch, M.; Hertenberger, R.; Holler, Y.; Holt, R. J.; Hoprich, W.; Ihssen, H.; Iodice, M.; Izotov, A.; Jackson, H. E.; Jgoun, A.; Jones, C. E.; Kaiser, R.; Kestel, M.; Kinney, E.; Kirsch, Matthias; Kisselev, A.; Kitching, P.; Kobayashi, Hisao; Koch, Norbert; Königsmann, K.; Kolstein, M.; Kolster, H.; Коротков, В. А.; Korsch, W.; Kozlov, V.; Kramer, L.; Krause, B.; Krivokhijine, V. G.; Kückes, M.; Kümmell, F.; Kurisuno, M.; Kyle, G. S.; Lachnit, W.; Lorenzon, W.; Lung, A.; Makins, N.; Martens, F. K.; Martin, J. W.; Marukyan, H.; Masoli, F.; Mateos, A.; Maul, M.; McAndrew, M.; McIlhany, K.; McKeown, R. D.; Meißner, F.; Menden, F.; Mercer, D.; Metz, A.; Meyners, N.; Mikloukho, O.; Miller, C. A.; Miller, M. A.; Milner, R.; Mitsyn, Valeri Valentinovitch; Mozzetti, R.; Muccifora, V.; Нагайцев, А.; Nappi, E.; Naryshkin, Y.; Nathan, Alan M.; Neunreither, F.; Niczyporuk, J. M.; Nowak, W.-D.; Nupieri, M.; Oelwein, P.; Ogami, H.; O’Neill, T. G.; Openshaw, R.; Owen, B.; Ouyang, J.; Papavassiliou, V.; Pate, S. F.; Pitt, M. L.; Poolman, H. R.; Potashov, S.; Potterveld, D. H.; Rakness, G.; Reali, A.; Redwine, R.; Reolon, A. R.; Ristinen, R.A.; Rith, Klaus; Röper, G.; Rossi, P.; Rudnitsky, S.; Ruh, M.; Ryckbosch, D.; Sakemi, Y.; Savin, I.; Scarlett, C.; Schäfer, Andreas; Schmidt, Friedrich; Schmitt, H.; Schnell, G.; Schüler, K. P.; Schwind, A.; Seibert, J. Anthony; Shibata, T. A.; Shibatani, K.; Shin, Taeho; Shutov, V.; Simani, C.; Simon, A.; Sinram, K.; Slavich, Pietro; Smythe, W. R.; Sowiński, J.; Spengos, M.; Steffens, E.; Stenger, J.; Stewart, J.; Stock, F.; Stoesslein, U.; Sutter, M.; Tallini, H.; Taroian, S.; Terkulov, A.; Thiessen, D.; Tipton, B.; Thomas, E.; Trudel, A.; Tytgat, M.; Urciuoli, G. M.; Hunen, J. J. van; Vyver, R. Van de; Brand, J. van den; Steenhoven, G. van der; Vetterli, M. C.; Vikhrov, V.; Vincter, M. G.; Visser, J.; Volk, E.; Wander, W.; Welch, T. P.; Wendland, J.; Williamson, S. E.; Wise, T.; Woller, K.; Yoneyama, Satoshi; Zapfe, K.; Zohrabian, H.; Zurmühle, R. W.

doi:10.1016/s0370-2693(99)00964-8

Cited by 160 publications

(79 citation statements)

References 55 publications

(35 reference statements)

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“…The structure functions are measured in deep-inelastic scattering of electrons off a nucleon [8][9][10][11][12][13][14][15][16][17][18][19], the cross section of which is factorized in terms of leptonic and hadronic tensors, / l W . Since the electron leptonic tensor, l , is known, the cross section provides us with structure information about the target nucleon through the hadronic tensor,…”

Section: Introductionmentioning

confidence: 99%

Nucleon isovector structure functions in (2+1)-flavor QCD with domain wall fermions

et al. 2010

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3. The right to use all or part of the Article, including the APS-prepared version without revision or modification, on the author(s)' web home page or employer's website and to make copies of all or part of the Article, including the APS-prepared version without revision or modification, for the author(s)' and/or the employer's use for educational or research purposes." 26th April 2013Nucleon isovector structure functions in (2 þ 1)-flavor QCD with domain wall fermions We report on numerical lattice QCD calculations of some of the low moments of the nucleon structure functions. The calculations are carried out with gauge configurations generated by the RBC and UKQCD Collaborations with (2 þ 1)-flavors of dynamical domain-wall fermions and the Iwasaki gauge action ( ¼ 2:13). The inverse lattice spacing is a À1 ¼ 1:73 GeV, and two spatial volumes of ð2:7 fmÞ 3 and ð1:8 fmÞ 3 are used. The up and down quark masses are varied so the pion mass lies between 0.33 and 0.67 GeV, while the strange mass is about 12% heavier than the physical one. The structure function moments we present include the fully nonperturbatively renormalized isovector quark momentum fraction hxi uÀd , the helicity fraction hxi ÁuÀÁd , and transversity h1i uÀ d , as well as an unrenormalized twist-3 coefficient d 1 . The ratio of the momentum to helicity fractions, hxi uÀd =hxi ÁuÀÁd , does not show dependence on the light quark mass and agrees well with the value obtained from experiment. Their respective absolute values, fully renormalized, show interesting trends toward their respective experimental values at the lightest quark mass. A prediction for the transversity, 0:7 < h1i uÀ d < 1:1, in the MS scheme at 2 GeV is obtained. The twist-3 coefficient, d 1 , though yet to be renormalized, supports the perturbative Wandzura-Wilczek relation.

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Section: Introductionmentioning

confidence: 99%

Nucleon isovector structure functions in (2+1)-flavor QCD with domain wall fermions

et al. 2010

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“…Data from inclusive and semi-inclusive deep inelastic scattering off polarized targets [1][2][3][4][5] and from upcoming polarized proton-proton collisions at RHIC [6] continue to improve on our knowledge on the polarized parton distributions in the nucleon. They parametrise the probability of finding partons inside the nucleon having their spin aligned or anti-aligned to the nucleon spin and are obtained from a global fit [7][8][9][10][11][12] to spin asymmetries in polarized lepton-hadron and hadron-hadron collisions.…”

Section: Introductionmentioning

confidence: 99%

Spin asymmetries in squark and gluino production at polarized hadron colliders

2004

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We study the production cross sections for squarks and gluinos in collision of longitudinally polarized hadrons. The corresponding polarized partonic cross sections are computed in leading order supersymmetric QCD. The resulting asymmetries are evaluated for the polarized proton collider RHIC, as well as for hypothetical polarized options of the Tevatron and the LHC. These asymmetries turn out to be sizable over a wide range of supersymmetric particle masses. Once supersymmetric particles are discovered in unpolarized collisions, a measurement of the spin asymmetries would thus potentially help to establish the properties of the newly discovered particles and open a window to detailed sparticle spectroscopy at future polarized hadron colliders.

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“…The first moments for the polarized valence and light sea quark flavours are compared in Tab. 8.4 with the results from the SMC experiment, which were integrated over the same kinematic [154]. …”

Section: Comparison With Results By the Spin Muon Collaborationmentioning

confidence: 99%

“…Similarly to the unpolarized parton distributions, it is based on a CPU-intensive parameterization of the ¾ space of the fragmentation parameters, which is currently not available. Instead, uncertainties were estimated by comparing the current tune with an older tune to HERMES data [153,154]. While this method is not strictly rigorous, it likely provides an upper estimate of the associated uncertainty.…”

Section: Generation Of the Puritiesmentioning

confidence: 99%

Polarized Parton Distributions Measured at the HERMES Experiment

Wendland

2004

AIP Conference Proceedings

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The HERMES experiment at DESY, Germany was designed to carry out precision measurements of the proton spin structure using polarized deep-inelastic scattering. The experiment utilizes the ¾ Î electron or positron beam of the HERA accelerator which is longitudinally polarized at HERMES, in combination with a polarized internal gas target. For this work, data on longitudinally polarized hydrogen and deuterium targets were used to determine cross section asymmetries with respect to the alignment of the target and beam polarizations. Inclusive asymmetries on the proton and the deuteron, where only the scattered electron/positron is detected, were measured with high precision. In semi-inclusive deep-inelastic scattering, at least one final-state hadron is detected in coincidence. Semi-inclusive asymmetries of pions on the proton and pion and kaon asymmetries on the deuteron were measured for the first time by the HERMES collaboration. The measured asymmetries include detector effects and effects of higher-order processes in quantum electrodynamics.A new unfolding procedure that takes into account the correlations between kinematic bins was implemented to correct for these effects.The polarized parton densities of the up, down, and sea flavours were obtained from the unfolded inclusive and semi-inclusive asymmetries in a probabilistic analysis based on leading-order quantum chromodynamics. In the case of the up quark and the down quark, the polarized densities were determined to be positive and negative, respectively. The polarized densities of the sea flavours, decomposed for the first time into the densities of the anti-up, anti-down, and strange quarks, were found to be compatible with zero. Moments of the polarized parton densities were computed. TheBjørken sum rule was verified and the total spin carried by the quark spins was determined to bé ¿ ¼ ¦ ¼µ ±. This latter result is larger than earlier measurements but still smaller than ¼ ± predicted in relativistic models of the proton.iii iv ABSTRACT AcknowledgementsFirst of all I would like to thank my adviser, Dr. Michel Vetterli, for providing the opportunity to conduct research on the nucleon spin structure. His support towards the completion of this work was indispensable. I would also like to thank the members of the ¡Õ-group, notably Thore Lindemann and Marc Beckmann, whose collaboration was invaluable.My thanks go to Elke Aschenauer for her tremendous efforts in running the experiment and in contributing to the analysis. I am indebted to Naomi Makins for the numerous discussions we had.

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

Cited by 160 publications

References 55 publications

Nucleon isovector structure functions in (2+1)-flavor QCD with domain wall fermions

Nucleon isovector structure functions in (2+1)-flavor QCD with domain wall fermions

Spin asymmetries in squark and gluino production at polarized hadron colliders

Polarized Parton Distributions Measured at the HERMES Experiment

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