Quasi-free \(\pi^0\) photoproduction from the bound nucleon

  • K. Kossert
  • M. Camen
  • F. Wissmann
  • J. Ahrens
  • Annand J. R. M. 
  • H.-J. Arends
  • R. Beck
  • G. Caselotti
  • P. Grabmayr
  • O. Jahn
  • P. Jennewein
  • M. I. Levchuk
  • A. I. L’vov
  • J. C. McGeorge
  • A. Natter
  • V. Olmos de León
  • V. A. Petrun’kin
  • G. Rosner
  • M. Schumacher
  • B. Seitz
  • F. Smend
  • A. Thomas
  • W. Weihofen
  • F. Zapadtka
Article

Abstract.

Differential cross-sections for quasi-free \(\pi^0\) photoproduction from the proton and neutron bound in the deuteron have been measured for \(E_\gamma = 200\mbox{--}400\) MeV at \(\theta_\gamma^{\rm lab} = 136.2^\circ\) using the Glasgow photon tagger at MAMI, the Mainz 48 cm \(\clubsuit\times 64\) cm NaI(Tl) photon detector and the Göttingen SENECA recoil detector. For the proton measurements made with both liquid-deuterium and liquid-hydrogen targets allow direct comparison of “free” \(\pi^0\) photoproduction cross-sections as extracted from the bound-proton data with experimental free cross-sections which are found to be in reasonable agreement below 320 MeV. At higher energies the “free” cross-sections extracted from quasi-free data are significantly smaller than the experimental free cross-sections and theoretical predictions based on multipole analysis. For the first time, “free” neutron cross-section have been extracted in the \(\Delta\)-region. They are also in agreement with the predictions from multipole analysis up to 320 MeV and significantly smaller at higher photon energies.

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Copyright information

© Springer-Verlag Berlin/Heidelberg 2004

Authors and Affiliations

  • K. Kossert
    • 1
  • M. Camen
    • 1
  • F. Wissmann
    • 1
  • J. Ahrens
    • 2
  • Annand J. R. M. 
    • 3
  • H.-J. Arends
    • 2
  • R. Beck
    • 2
  • G. Caselotti
    • 2
  • P. Grabmayr
    • 4
  • O. Jahn
    • 2
  • P. Jennewein
    • 2
  • M. I. Levchuk
    • 5
  • A. I. L’vov
    • 6
  • J. C. McGeorge
    • 3
  • A. Natter
    • 4
  • V. Olmos de León
    • 2
  • V. A. Petrun’kin
    • 6
  • G. Rosner
    • 3
  • M. Schumacher
    • 1
  • B. Seitz
    • 1
  • F. Smend
    • 1
  • A. Thomas
    • 2
  • W. Weihofen
    • 1
  • F. Zapadtka
    • 1
  1. 1.II. Physikalisches InstitutUniversität GöttingenGöttingenGermany
  2. 2.Institut für KernphysikUniversität MainzMainzGermany
  3. 3.Department of Physics and AstronomyUniversity of GlasgowGlasgowUK
  4. 4.Physikalisches InstitutUniversität TübingenTübingenGermany
  5. 5.B.I. Stepanov Institute of PhysicsBelarussian Academy of SciencesMinskBelarus
  6. 6.P.N. Lebedev Physical InstituteMoscowRussia

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