English

New Insight in the $Q^2$-Dependence of Proton Generalized Polarizabilities

Nuclear Experiment 2019-11-13 v2

Abstract

Virtual Compton scattering on the proton has been investigated at three yet unexplored values of the four-momentum transfer Q2Q^2: 0.10, 0.20 and 0.45 GeV2^2, at the Mainz Microtron. Fits performed using either the low-energy theorem or dispersion relations allowed the extraction of the structure functions PLLPTT/ϵP_{LL} -P_{TT} / \epsilon and PLTP_{LT}, as well as the electric and magnetic generalized polarizabilities αE1(Q2)\alpha_{E1}(Q^2) and βM1(Q2)\beta_{M1}(Q^2). These new results show a smooth and rapid fall-off of αE1(Q2)\alpha_{E1}(Q^2), in contrast to previous measurements at Q2Q^2 = 0.33 GeV2^2, and provide for the first time a precise mapping of βM1(Q2)\beta_{M1}(Q^2) in the low-Q2Q^2 region.

Keywords

Cite

@article{arxiv.1907.09954,
  title  = {New Insight in the $Q^2$-Dependence of Proton Generalized Polarizabilities},
  author = {J. Beričič and L. Correa and M. Benali and P. Achenbach and C. Ayerbe Gayoso and J. C. Bernauer and A. Blomberg and R. Böhm and D. Bosnar and L. Debenjak and A. Denig and M. O. Distler and E. J. Downie and A. Esser and H. Fonvieille and I. Friščić and S. Kegel and Y. Kohl and M. Makek and H. Merkel and D. G. Middleton and M. Mihovilovič and U. Müller and L. Nungesser and M. Paolone and J. Pochodzalla and S. Sánchez Majos and B. S. Schlimme and M. Schoth and F. Schulz and C. Sfienti and S. Širca and N. Sparveris and S. Štajner and M. Thiel and A. Tyukin and A. Weber and M. Weinriefer},
  journal= {arXiv preprint arXiv:1907.09954},
  year   = {2019}
}

Comments

5 pages, 1 figure .eps. Version accepted by PRL