Elastic-Scattering Measurement of the Negative-Pion Radius

E. B. Dally; J. M. Hauptman; J. Kubic; D. H. Stork; A. B. Watson; Z. Guzik; T. S. Nigmanov; V. D. Riabtsoy; E. N. Tsyganov; A. S. Vodopianov; A. Beretvas; A. Grigorian; J. C. Tompkins; T. E. Toohig; A. A. Wehmann; J. A. Poirier; C. A. Rey; J. T. Volk; P. D. Rapp; P. F. Shepard

doi:10.1103/PhysRevLett.48.375

Elastic-Scattering Measurement of the Negative-Pion Radius

E. B. Dally, J. M. Hauptman, J. Kubic, D. H. Stork, A. B. Watson, Z. Guzik, T. S. Nigmanov, V. D. Riabtsoy, E. N. Tsyganov, A. S. Vodopianov, A. Beretvas, A. Grigorian, J. C. Tompkins, T. E. Toohig, A. A. Wehmann, J. A. Poirier, C. A. Rey, J. T. Volk, P. D. Rapp, and P. F. Shepard

Phys. Rev. Lett. 48, 375 – Published 8 February 1982

Abstract

A new measurement of the elastic scattering of 250-GeV/c negative pions by electrons provides form-factor results from $0.0368 < q^{2} < 0.0940$ ${(G e V / c)}^{2}$ . These measurements determine the mean square pion radius to be $〈 {r_{π}}^{2} 〉 = 0.439 \pm 0.030$ ${fm}^{2}$ or ${〈 {r_{π}}^{2} 〉}^{\frac{1}{2}} = 0.663 \pm 0.023$ fm. Comparisons are made with previous elastic-scattering experiments as well as with results obtained from electroproduction experiments, $e^{+} e^{-}$ annihilation experiments, and phenomenological analyses.

Received 21 August 1981

DOI:https://doi.org/10.1103/PhysRevLett.48.375

Authors & Affiliations

E. B. Dally^*, J. M. Hauptman^†, J. Kubic, D. H. Stork, and A. B. Watson

Physics Department, University of California, Los Angeles, California 90024

Z. Guzik, T. S. Nigmanov, V. D. Riabtsoy, E. N. Tsyganov, and A. S. Vodopianov

Joint Institute for Nuclear Research, Dubna, U.S.S.R.

A. Beretvas^‡, A. Grigorian^§, J. C. Tompkins^∥, T. E. Toohig, and A. A. Wehmann

Fermi National Accelerator Laboratory, Batavia, Illinois 60510

J. A. Poirier, C. A. Rey^¶, and J. T. Volk^**

Physics Department, University of Notre Dame, Notre Dame, Indiana 46556

P. D. Rapp^†† and P. F. Shepard

Physics Department, University of Pittsburgh, Pittsburgh, Pennsylvania 15620

^*Present address: Siemens Medical Laboratories, Walnut Creek, Cal. 94596.
^†Present address: Lawrence Berkeley Laboratory, University of California, Berkeley, Cal. 94720.
^‡Present address: Rutgers University, Piscataway, N. J. 08854.
^§Present address: Hughes Aircraft Co., Culver City, Cal. 90230.
^∥Present address: High Energy Physics Laboratory, Stanford University, Stanford, Cal. 94305.
^¶Present address: Intersonics, Inc., Northbrook, Ill. 60062.
^**Present address: Ohio State University, Columbus, Ohio 43210.
^††Present address: Fermi National Accelerator Laboratory, Batavia, Ill. 60510.