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Exclusive leptoproduction of real photons on a longitudinally polarised hydrogen target

  • HERMES collaboration
  • A. Airapetian
  • N. Akopov
  • Z. Akopov
  • E. C. Aschenauer
  • W. Augustyniak
  • R. Avakian
  • A. Avetissian
  • E. Avetisyan
  • B. Ball
  • S. Belostotski
  • N. Bianchi
  • H. P. Blok
  • H. Böttcher
  • A. Borissov
  • J. Bowles
  • I. Brodski
  • V. Bryzgalov
  • J. Burns
  • M. Capiluppi
  • G. P. Capitani
  • E. Cisbani
  • G. Ciullo
  • M. Contalbrigo
  • P. F. Dalpiaz
  • W. Deconinck
  • R. De Leo
  • L. De Nardo
  • E. De Sanctis
  • M. Diefenthaler
  • P. Di Nezza
  • M. Düren
  • M. Ehrenfried
  • G. Elbakian
  • F. Ellinghaus
  • R. Fabbri
  • A. Fantoni
  • L. Felawka
  • S. Frullani
  • D. Gabbert
  • G. Gapienko
  • V. Gapienko
  • F. Garibaldi
  • G. Gavrilov
  • V. Gharibyan
  • F. Giordano
  • S. Gliske
  • M. Golembiovskaya
  • C. Hadjidakis
  • M. Hartig
  • D. Hasch
  • G. Hill
  • A. Hillenbrand
  • M. Hoek
  • Y. Holler
  • I. Hristova
  • Y. Imazu
  • A. Ivanilov
  • A. Izotov
  • H. E. Jackson
  • H. S. Jo
  • S. Joosten
  • R. Kaiser
  • G. Karyan
  • T. Keri
  • E. Kinney
  • A. Kisselev
  • N. Kobayashi
  • V. Korotkov
  • V. Kozlov
  • P. Kravchenko
  • V. G. Krivokhijine
  • L. Lagamba
  • R. Lamb
  • L. Lapikás
  • I. Lehmann
  • P. Lenisa
  • L. A. Linden-Levy
  • A. López Ruiz
  • W. Lorenzon
  • X.-G. Lu
  • X.-R. Lu
  • B.-Q. Ma
  • D. Mahon
  • N. C. R. Makins
  • S. I. Manaenkov
  • L. Manfré
  • Y. Mao
  • B. Marianski
  • A. Martinez de la Ossa
  • H. Marukyan
  • C. A. Miller
  • Y. Miyachi
  • A. Movsisyan
  • V. Muccifora
  • M. Murray
  • A. Mussgiller
  • E. Nappi
  • Y. Naryshkin
  • A. Nass
  • M. Negodaev
  • W.-D. Nowak
  • L. L. Pappalardo
  • R. Perez-Benito
  • N. Pickert
  • M. Raithel
  • P. E. Reimer
  • A. R. Reolon
  • C. Riedl
  • K. RithEmail author
  • G. Rosner
  • A. Rostomyan
  • J. Rubin
  • D. Ryckbosch
  • Y. Salomatin
  • F. Sanftl
  • A. Schäfer
  • G. Schnell
  • K. P. Schüler
  • B. Seitz
  • T.-A. Shibata
  • V. Shutov
  • M. Stancari
  • M. Statera
  • E. Steffens
  • J. J. M. Steijger
  • H. Stenzel
  • J. Stewart
  • F. Stinzing
  • S. Taroian
  • A. Terkulov
  • A. Trzcinski
  • M. Tytgat
  • A. Vandenbroucke
  • P. B. van der Nat
  • Y. Van Haarlem
  • C. Van Hulse
  • D. Veretennikov
  • V. Vikhrov
  • I. Vilardi
  • C. Vogel
  • S. Wang
  • S. Yaschenko
  • H. Ye
  • Z. Ye
  • S. Yen
  • W. Yu
  • D. Zeiler
  • B. Zihlmann
  • P. Zupranski
Open Access
Article

Abstract

Polarisation asymmetries are measured for the hard exclusive leptoproduction of real photons from a longitudinally polarised hydrogen target. These asymmetries arise from the deeply virtual Compton scattering and Bethe-Heitler processes. From the data are extracted two asymmetries in the azimuthal distribution of produced real photons about the direction of the exchanged virtual photon: \( {\mathcal{A}_{\text{UL}}} \) with respect to the target polarisation and \( {\mathcal{A}_{\text{LL}}} \) with respect to the product of the beam and target polarisations. Results for both asymmetries are compared to the predictions from a generalised parton distribution model. The sin φ and cos(0φ) amplitudes observed respectively for the \( {\mathcal{A}_{\text{UL}}} \) and \( {\mathcal{A}_{\text{LL}}} \) asymmetries are compatible with the sizeable predictions from the model. Unexpectedly, a sin(2φ) modulation in the \( {\mathcal{A}_{\text{UL}}} \) asymmetry with a magnitude similar to that of the sin φ modulation is observed.

Keywords

Lepton-Nucleon Scattering 

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Copyright information

© The Author(s) 2010

Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  • HERMES collaboration
  • A. Airapetian
    • 12
    • 15
  • N. Akopov
    • 26
  • Z. Akopov
    • 5
  • E. C. Aschenauer
    • 6
  • W. Augustyniak
    • 25
  • R. Avakian
    • 26
  • A. Avetissian
    • 26
  • E. Avetisyan
    • 5
  • B. Ball
    • 15
  • S. Belostotski
    • 18
  • N. Bianchi
    • 10
  • H. P. Blok
    • 17
    • 24
  • H. Böttcher
    • 6
  • A. Borissov
    • 5
  • J. Bowles
    • 13
  • I. Brodski
    • 12
  • V. Bryzgalov
    • 19
  • J. Burns
    • 13
  • M. Capiluppi
    • 9
  • G. P. Capitani
    • 10
  • E. Cisbani
    • 21
  • G. Ciullo
    • 9
  • M. Contalbrigo
    • 9
  • P. F. Dalpiaz
    • 9
  • W. Deconinck
    • 5
  • R. De Leo
    • 2
  • L. De Nardo
    • 5
    • 11
  • E. De Sanctis
    • 10
  • M. Diefenthaler
    • 8
    • 14
  • P. Di Nezza
    • 10
  • M. Düren
    • 12
  • M. Ehrenfried
    • 12
  • G. Elbakian
    • 26
  • F. Ellinghaus
    • 4
  • R. Fabbri
    • 6
  • A. Fantoni
    • 10
  • L. Felawka
    • 22
  • S. Frullani
    • 21
  • D. Gabbert
    • 6
    • 11
  • G. Gapienko
    • 19
  • V. Gapienko
    • 19
  • F. Garibaldi
    • 21
  • G. Gavrilov
    • 5
    • 18
    • 22
  • V. Gharibyan
    • 26
  • F. Giordano
    • 5
    • 9
  • S. Gliske
    • 15
  • M. Golembiovskaya
    • 6
  • C. Hadjidakis
    • 10
  • M. Hartig
    • 5
  • D. Hasch
    • 10
  • G. Hill
    • 13
  • A. Hillenbrand
    • 6
  • M. Hoek
    • 13
  • Y. Holler
    • 5
  • I. Hristova
    • 6
  • Y. Imazu
    • 23
  • A. Ivanilov
    • 19
  • A. Izotov
    • 18
  • H. E. Jackson
    • 1
  • H. S. Jo
    • 11
  • S. Joosten
    • 11
    • 14
  • R. Kaiser
    • 13
  • G. Karyan
    • 26
  • T. Keri
    • 12
    • 13
  • E. Kinney
    • 4
  • A. Kisselev
    • 18
  • N. Kobayashi
    • 23
  • V. Korotkov
    • 19
  • V. Kozlov
    • 16
  • P. Kravchenko
    • 18
  • V. G. Krivokhijine
    • 7
  • L. Lagamba
    • 2
  • R. Lamb
    • 14
  • L. Lapikás
    • 17
  • I. Lehmann
    • 13
  • P. Lenisa
    • 9
  • L. A. Linden-Levy
    • 14
  • A. López Ruiz
    • 11
  • W. Lorenzon
    • 15
  • X.-G. Lu
    • 6
  • X.-R. Lu
    • 23
  • B.-Q. Ma
    • 3
  • D. Mahon
    • 13
  • N. C. R. Makins
    • 14
  • S. I. Manaenkov
    • 18
  • L. Manfré
    • 21
  • Y. Mao
    • 3
  • B. Marianski
    • 25
  • A. Martinez de la Ossa
    • 4
  • H. Marukyan
    • 26
  • C. A. Miller
    • 22
  • Y. Miyachi
    • 23
  • A. Movsisyan
    • 26
  • V. Muccifora
    • 10
  • M. Murray
    • 13
  • A. Mussgiller
    • 5
    • 8
  • E. Nappi
    • 2
  • Y. Naryshkin
    • 18
  • A. Nass
    • 8
  • M. Negodaev
    • 6
  • W.-D. Nowak
    • 6
  • L. L. Pappalardo
    • 9
  • R. Perez-Benito
    • 12
  • N. Pickert
    • 8
  • M. Raithel
    • 8
  • P. E. Reimer
    • 1
  • A. R. Reolon
    • 10
  • C. Riedl
    • 6
  • K. Rith
    • 8
    Email author
  • G. Rosner
    • 13
  • A. Rostomyan
    • 5
  • J. Rubin
    • 14
  • D. Ryckbosch
    • 11
  • Y. Salomatin
    • 19
  • F. Sanftl
    • 20
  • A. Schäfer
    • 20
  • G. Schnell
    • 6
    • 11
  • K. P. Schüler
    • 5
  • B. Seitz
    • 13
  • T.-A. Shibata
    • 23
  • V. Shutov
    • 7
  • M. Stancari
    • 9
  • M. Statera
    • 9
  • E. Steffens
    • 8
  • J. J. M. Steijger
    • 17
  • H. Stenzel
    • 12
  • J. Stewart
    • 6
  • F. Stinzing
    • 8
  • S. Taroian
    • 26
  • A. Terkulov
    • 16
  • A. Trzcinski
    • 25
  • M. Tytgat
    • 11
  • A. Vandenbroucke
    • 11
  • P. B. van der Nat
    • 17
  • Y. Van Haarlem
    • 11
  • C. Van Hulse
    • 11
  • D. Veretennikov
    • 18
  • V. Vikhrov
    • 18
  • I. Vilardi
    • 2
  • C. Vogel
    • 8
  • S. Wang
    • 3
  • S. Yaschenko
    • 6
    • 8
  • H. Ye
    • 3
  • Z. Ye
    • 5
  • S. Yen
    • 22
  • W. Yu
    • 12
  • D. Zeiler
    • 8
  • B. Zihlmann
    • 5
  • P. Zupranski
    • 25
  1. 1.Physics DivisionArgonne National LaboratoryArgonneU.S.A.
  2. 2.Istituto Nazionale di Fisica NucleareSezione di BariBariItaly
  3. 3.School of PhysicsPeking UniversityBeijingChina
  4. 4.Nuclear Physics LaboratoryUniversity of ColoradoBoulderU.S.A.
  5. 5.DESYHamburgGermany
  6. 6.DESYZeuthenGermany
  7. 7.Joint Institute for Nuclear ResearchDubnaRussia
  8. 8.Physikalisches InstitutUniversität Erlangen-NürnbergErlangenGermany
  9. 9.Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara and Dipartimento di FisicaUniversità di FerraraFerraraItaly
  10. 10.Istituto Nazionale di Fisica NucleareLaboratori Nazionali di FrascatiFrascatiItaly
  11. 11.Department of Subatomic and Radiation PhysicsUniversity of GentGentBelgium
  12. 12.Physikalisches InstitutUniversität GießenGießenGermany
  13. 13.Department of Physics and AstronomyUniversity of GlasgowGlasgowU.K.
  14. 14.Department of PhysicsUniversity of IllinoisUrbanaU.S.A.
  15. 15.Randall Laboratory of PhysicsUniversity of MichiganAnn ArborU.S.A.
  16. 16.Lebedev Physical InstituteMoscowRussia
  17. 17.National Institute for Subatomic Physics (Nikhef)AmsterdamThe Netherlands
  18. 18.Petersburg Nuclear Physics InstituteGatchinaRussia
  19. 19.Institute for High Energy PhysicsProtvinoRussia
  20. 20.Institut für Theoretische PhysikUniversität RegensburgRegensburgGermany
  21. 21.Istituto Nazionale di Fisica Nucleare, Sezione Roma 1Gruppo Sanità and Physics Laboratory, Istituto Superiore di SanitàRomaItaly
  22. 22.TRIUMFVancouverCanada
  23. 23.Department of PhysicsTokyo Institute of TechnologyTokyoJapan
  24. 24.Department of Physics & AstronomyVU UniversityAmsterdamThe Netherlands
  25. 25.Andrzej Soltan Institute for Nuclear StudiesWarsawPoland
  26. 26.Yerevan Physics InstituteYerevanArmenia

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