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Photoproduction of \(\eta\) \(\pi\) pairs off nucleons and deuterons

  • The A2 Collaboration
  • A. Käser
  • F. Müller
  • J. Ahrens
  • J. R. M. Annand
  • H. J. Arends
  • K. Bantawa
  • P. A. Bartolome
  • R. Beck
  • A. Braghieri
  • W. J. Briscoe
  • S. Cherepnya
  • S. Costanza
  • M. Dieterle
  • E. J. Downie
  • P. Drexler
  • L. V. Fil’kov
  • A. Fix
  • S. Garni
  • D. I. Glazier
  • D. Hamilton
  • D. Hornidge
  • D. Howdle
  • G. M. Huber
  • I. Jaegle
  • T. C. Jude
  • V. L. Kashevarov
  • I. Keshelashvili
  • R. Kondratiev
  • M. Korolija
  • B. KruscheEmail author
  • V. Lisin
  • K. Livingston
  • I. J. D. MacGregor
  • Y. Maghrbi
  • J. Mancell
  • D. M. Manley
  • Z. Marinides
  • J. C. McGeorge
  • E. McNicoll
  • D. Mekterovic
  • V. Metag
  • S. Micanovic
  • D. G. Middleton
  • A. Mushkarenkov
  • A. Nikolaev
  • R. Novotny
  • M. Oberle
  • M. Ostrick
  • P. Otte
  • B. Oussena
  • P. Pedroni
  • F. Pheron
  • A. Polonski
  • S. Prakhov
  • J. Robinson
  • T. Rostomyan
  • S. Schumann
  • M. H. Sikora
  • D. Sober
  • A. Starostin
  • Th. Strub
  • I. Supek
  • M. Thiel
  • A. Thomas
  • M. Unverzagt
  • N. K. Walford
  • D. P. Watts
  • D. Werthmüller
  • L. Witthauer
Regular Article - Experimental Physics

Abstract.

Quasi-free photoproduction of \(\pi\eta\)-pairs has been investigated from threshold up to incident photon energies of 1.4 GeV, respectively up to photon-nucleon invariant masses up to 1.9 GeV. Total cross sections, angular distributions, invariant-mass distributions of the \( \pi\eta\) and meson-nucleon pairs, and beam-helicity asymmetries have been measured for the reactions \( \gamma p\rightarrow p\pi^{0}\eta\), \( \gamma n\rightarrow n\pi^{0}\eta\) , \( \gamma p\rightarrow n\pi^{+}\eta\) , and \(\gamma n\rightarrow p\pi^{-}\eta\) from nucleons bound inside the deuteron. For the \(\gamma p\) initial-state data for free protons have also been analyzed. Finally, the total cross sections for quasi-free production of \( \pi^{0}\eta\) pairs from nucleons bound in 3 He nuclei have been investigated in view of final state interaction (FSI) effects. The experiments were performed at the tagged photon beam facility of the Mainz MAMI accelerator using an almost 4\( \pi\) covering electromagnetic calorimeter composed of the Crystal Ball and TAPS detectors. The shapes of all differential cross section data and the asymmetries are very similar for protons and neutrons and agree with the conjecture that the reactions are dominated by the sequential \( \Delta^{\star}3/2^{-}\rightarrow \eta\Delta(1232) \rightarrow\pi\eta N\) decay chain, mainly with \( \Delta(1700)3/2^{-}\) and \( \Delta(1940)3/2^{-}\) . The ratios of the magnitude of the total cross sections also agree with this assumption. However, the absolute magnitudes of the cross sections are reduced by FSI effects with respect to free proton data.

References

  1. 1.
    W.T. Chiang, F. Tabakin, Phys. Rev. C 55, 2054 (1997)ADSCrossRefGoogle Scholar
  2. 2.
    W. Roberts, T. Oed, Phys. Rev. C 71, 055201 (2005)ADSCrossRefGoogle Scholar
  3. 3.
    A.V. Sarantsev et al., Phys. Lett. B 659, 94 (2008)ADSCrossRefGoogle Scholar
  4. 4.
    U. Thoma et al., Phys. Lett. B 659, 87 (2008)ADSCrossRefGoogle Scholar
  5. 5.
    D. Krambrich et al., Phys. Rev. Lett. 103, 052002 (2009)ADSCrossRefGoogle Scholar
  6. 6.
    V.L. Kashevarov et al., Phys. Rev. C 85, 064610 (2012)ADSCrossRefGoogle Scholar
  7. 7.
    F. Zehr et al., Eur. Phys. J. A 48, 98 (2012)ADSCrossRefGoogle Scholar
  8. 8.
    M. Oberle et al., Phys. Lett. B 721, 237 (2013)ADSCrossRefGoogle Scholar
  9. 9.
    M. Oberle et al., Eur. Phys. J. A 50, 54 (2014)ADSCrossRefGoogle Scholar
  10. 10.
    A. Thiel et al., Phys. Rev. Lett. 114, 091803 (2015)ADSCrossRefGoogle Scholar
  11. 11.
    V. Sokhoyan et al., Phys. Lett. B 746, 127 (2015)ADSCrossRefGoogle Scholar
  12. 12.
    V. Sokhoyan et al., Eur. Phys. J. A 51, 95 (2015)ADSCrossRefGoogle Scholar
  13. 13.
    M. Dieterle et al., Eur. Phys. J. A 51, 142 (2015)ADSCrossRefGoogle Scholar
  14. 14.
    T. Nakabayashi et al., Phys. Rev. C 74, 035202 (2006)ADSCrossRefGoogle Scholar
  15. 15.
    J. Ajaka et al., Phys. Rev. Lett. 100, 052003 (2008)ADSCrossRefGoogle Scholar
  16. 16.
    I. Horn et al., Phys. Rev. Lett. 101, 202002 (2008)ADSCrossRefGoogle Scholar
  17. 17.
    I. Horn et al., Eur. Phys. J. A 38, 173 (2008)ADSCrossRefGoogle Scholar
  18. 18.
    E. Gutz et al., Eur. Phys. J. A 35, 291 (2008)ADSCrossRefGoogle Scholar
  19. 19.
    E. Gutz et al., Phys. Lett. B 687, 11 (2010)ADSCrossRefGoogle Scholar
  20. 20.
    E. Gutz et al., Eur. Phys. J. A 50, 74 (2014)ADSCrossRefGoogle Scholar
  21. 21.
    V. Kashevarov et al., Eur. Phys. J. A 42, 141 (2009)ADSCrossRefGoogle Scholar
  22. 22.
    V. Kashevarov et al., Phys. Lett. B 693, 551 (2010)ADSCrossRefGoogle Scholar
  23. 23.
    B. Krusche, C. Wilkin, Prog. Part. Nucl. Phys. 80, 43 (2015)ADSCrossRefGoogle Scholar
  24. 24.
    A. Fix, V.L. Kashevarov, A. Lee, M. Ostrick, Phys. Rev. C 82, 035207 (2010) and private communicationADSCrossRefGoogle Scholar
  25. 25.
    A. Fix, H. Arenhövel, Phys. Rev. C 83, 015503 (2011)ADSCrossRefGoogle Scholar
  26. 26.
    M. Döring, E. Oset, D. Strottman, Phys. Lett. B 639, 59 (2006)ADSCrossRefGoogle Scholar
  27. 27.
    M. Döring, E. Oset, D. Strottman, Phys. Rev. C 73, 045209 (2006)ADSCrossRefGoogle Scholar
  28. 28.
    A. Käser et al., Phys. Lett. B 748, 244 (2015)ADSCrossRefGoogle Scholar
  29. 29.
    B. Krusche, Eur. Phys. J. ST 198, 199 (2011)CrossRefGoogle Scholar
  30. 30.
    D. Werthmüller et al., Phys. Rev. Lett. 111, 232001 (2013)ADSCrossRefGoogle Scholar
  31. 31.
    D. Werthmüller et al., Phys. Rev. C 90, 015205 (2014)ADSCrossRefGoogle Scholar
  32. 32.
    M. Dieterle et al., Phys. Rev. Lett. 112, 142001 (2014)ADSCrossRefGoogle Scholar
  33. 33.
    F. Pheron et al., Phys. Lett. B 709, 21 (2012)ADSCrossRefGoogle Scholar
  34. 34.
    L. Witthauer et al., Eur. Phys. J. A 49, 154 (2013)ADSCrossRefGoogle Scholar
  35. 35.
    H. Herminghaus et al., IEEE Trans. Nucl. Sci. 30, 3274 (1983)ADSCrossRefGoogle Scholar
  36. 36.
    Th. Walcher, Prog. Part. Nucl. Phys. 24, 189 (1990)ADSCrossRefGoogle Scholar
  37. 37.
    I. Anthony et al., Nucl. Instrum. Methods A 301, 230 (1991)ADSCrossRefGoogle Scholar
  38. 38.
    S.J. Hall, G.J. Miller, R. Beck, P. Jennewein, Nucl. Instrum. Methods A 368, 698 (1996)ADSCrossRefGoogle Scholar
  39. 39.
    J.C. McGeorge et al., Eur. Phys. J. A 37, 129 (2008)ADSCrossRefGoogle Scholar
  40. 40.
    H. Olsen, L.C. Maximon, Phys. Rev. 114, 887 (1959)ADSMathSciNetCrossRefGoogle Scholar
  41. 41.
    A. Starostin et al., Phys. Rev. C 64, 055205 (2001)ADSCrossRefGoogle Scholar
  42. 42.
    R. Novotny, IEEE Trans. Nucl. Sci. 38, 379 (1991)ADSCrossRefGoogle Scholar
  43. 43.
    A.R. Gabler et al., Nucl. Instrum. Methods A 346, 168 (1994)ADSCrossRefGoogle Scholar
  44. 44.
    D. Watts, in Calorimetry in Particle Physics, Proceedings of the 11th Internatinal Conference, Perugia, Italy 2004, edited by C. Cecchi, P. Cenci, P. Lubrano, M. Pepe (World Scientific, Singapore, 2005) p. 560Google Scholar
  45. 45.
    S. Agostinelli et al., Nucl. Instrum. Methods A 506, 250 (2003)ADSCrossRefGoogle Scholar
  46. 46.
    B. Krusche, S. Schadmand, Prog. Part. Nucl. Phys. 51, 399 (2003)ADSCrossRefGoogle Scholar
  47. 47.
    M. Egorov, A. Fix, Phys. Rev. C 88, 054611 (2013)ADSCrossRefGoogle Scholar
  48. 48.
    M. Pfeiffer et al., Phys. Rev. Lett. 92, 252001 (2004)ADSCrossRefGoogle Scholar
  49. 49.
    B. Krusche et al., Phys. Rev. Lett. 74, 3736 (1995)ADSCrossRefGoogle Scholar
  50. 50.
    B. Krusche et al., Phys. Lett. B 397, 171 (1997)ADSCrossRefGoogle Scholar

Copyright information

© SIF, Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • The A2 Collaboration
  • A. Käser
    • 1
  • F. Müller
    • 1
  • J. Ahrens
    • 2
  • J. R. M. Annand
    • 3
  • H. J. Arends
    • 2
  • K. Bantawa
    • 4
  • P. A. Bartolome
    • 2
  • R. Beck
    • 2
    • 5
  • A. Braghieri
    • 6
  • W. J. Briscoe
    • 7
  • S. Cherepnya
    • 8
  • S. Costanza
    • 6
  • M. Dieterle
    • 1
  • E. J. Downie
    • 2
    • 3
    • 7
  • P. Drexler
    • 9
  • L. V. Fil’kov
    • 8
  • A. Fix
    • 10
  • S. Garni
    • 1
  • D. I. Glazier
    • 3
    • 11
  • D. Hamilton
    • 3
  • D. Hornidge
    • 12
  • D. Howdle
    • 3
  • G. M. Huber
    • 13
  • I. Jaegle
    • 1
  • T. C. Jude
    • 11
  • V. L. Kashevarov
    • 2
    • 8
  • I. Keshelashvili
    • 1
  • R. Kondratiev
    • 14
  • M. Korolija
    • 15
  • B. Krusche
    • 1
    Email author
  • V. Lisin
    • 14
  • K. Livingston
    • 3
  • I. J. D. MacGregor
    • 3
  • Y. Maghrbi
    • 1
  • J. Mancell
    • 3
  • D. M. Manley
    • 4
  • Z. Marinides
    • 7
  • J. C. McGeorge
    • 3
  • E. McNicoll
    • 3
  • D. Mekterovic
    • 15
  • V. Metag
    • 9
  • S. Micanovic
    • 15
  • D. G. Middleton
    • 12
  • A. Mushkarenkov
    • 6
  • A. Nikolaev
    • 2
    • 5
  • R. Novotny
    • 9
  • M. Oberle
    • 1
  • M. Ostrick
    • 2
  • P. Otte
    • 2
  • B. Oussena
    • 2
    • 7
  • P. Pedroni
    • 6
  • F. Pheron
    • 1
  • A. Polonski
    • 14
  • S. Prakhov
    • 16
  • J. Robinson
    • 3
  • T. Rostomyan
    • 1
  • S. Schumann
    • 2
    • 5
  • M. H. Sikora
    • 11
  • D. Sober
    • 17
  • A. Starostin
    • 16
  • Th. Strub
    • 1
  • I. Supek
    • 15
  • M. Thiel
    • 9
  • A. Thomas
    • 2
  • M. Unverzagt
    • 2
    • 5
  • N. K. Walford
    • 1
  • D. P. Watts
    • 11
  • D. Werthmüller
    • 1
    • 3
  • L. Witthauer
    • 1
  1. 1.Department of PhysicsUniversity of BaselBaselSwitzerland
  2. 2.Institut für KernphysikUniversity of MainzMainzGermany
  3. 3.SUPA School of Physics and AstronomyUniversity of GlasgowGlasgowUK
  4. 4.Kent State UniversityKentUSA
  5. 5.Helmholtz-Institut für Strahlen- und KernphysikUniversity BonnBonnGermany
  6. 6.INFN Sezione di PaviaPaviaItaly
  7. 7.Center for Nuclear StudiesThe George Washington UniversityWashingtonUSA
  8. 8.Lebedev Physical InstituteMoscowRussia
  9. 9.II. Physikalisches InstitutUniversity of GiessenGiessenGermany
  10. 10.Laboratory of Mathematical PhysicsTomsk Polytechnic UniversityTomskRussia
  11. 11.SUPA School of PhysicsUniversity of EdinburghEdinburghUK
  12. 12.Mount Allison UniversitySackvilleCanada
  13. 13.University of ReginaReginaCanada
  14. 14.Institute for Nuclear ResearchMoscowRussia
  15. 15.Rudjer Boskovic InstituteZagrebCroatia
  16. 16.University of California Los AngelesLos AngelesUSA
  17. 17.The Catholic University of AmericaWashingtonUSA

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