Determination of the pion charge form factor at Q2=1.60 and 2.45 (GeV/c)2.
The 1H(e,e'pi+)n cross section was measured at four-momentum transfers of Q2=1.60 and 2.45 GeV2 at an invariant mass of the photon nucleon system of W=2.22 GeV. The charged pion form factor (F(pi)) was extracted from the data by comparing the separated longitudinal pion electroproduction cross section to a Regge model prediction in which F(pi) is a free parameter. The results indicate that the pion form factor deviates from the charge-radius constrained monopole form at these values of Q2 by one sigma, but is still far from its perturbative quantum chromodynamics prediction.
Horn
T
T
Department of Physics, University of Maryland, College Park, MD 20742, USA.
Aniol
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Arrington
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Barrett
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Beise
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Blok
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Boeglin
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Brash
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Breuer
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Chang
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Christy
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Gaskell
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Gibson
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Holt
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Huber
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Jones
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Keppel
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Kim
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King
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Kovaltchouk
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Liu
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Lolos
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Mack
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Margaziotis
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Markowitz
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Matsumura
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Meekins
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Miyoshi
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Mkrtchyan
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Niculescu
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Okayasu
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Pentchev
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Perdrisat
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Potterveld
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Punjabi
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Reimer
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Reinhold
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Roche
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Roos
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Sarty
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Smith
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Tadevosyan
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Tang
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Tvaskis
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Vidakovic
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Volmer
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Vulcan
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Warren
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Wood
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Xu
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Zheng
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