CLAS Physics Database

e1-6a run CLAS data

Spokespersons
P. Khetarpal, P. Stoler, I. Aznauryan, V. Kubarovsky,
Year
2012
Abstract
We report the measurement of near threshold neutral pion electroproduction cross sections on the proton in the kinematic range $Q^2$ from 2 to 4.5 GeV$^2$ and $W$ from 1.08 to 1.16 GeV.
Comment
These measurements allow us to access the dominant pion-nucleon s-wave multipoles $E_{0+}$ and $S_{0+}$ in the near-threshold region. In the light-cone sum-rule framework (LCSR), these multipoles are related to the generalized form factors $G_1^{\pi^0 p}(Q^2)$ and $G_2^{\pi^0 p}(Q^2)$.
Publication
  1. P. Khetarpal, P. Stoler, I. Aznauryan, V. Kubarovsky Near Threshold Neutral Pion Electroproduction at High Momentum Transfers and Generalized Form Factors // Phys. Rev. C 87, 045205 (2013); http://arxiv.org/abs/1211.6460
Quantities
d2σ/dcos(θπ)dφπ

Measurements

ID Quantity Beam Target Final state Q2min,
GeV2
Q2max,
GeV2
Wmin,
GeV
Wmax,
GeV
E136M1 d2σ/dcos(θπ)dφπ e p π0p 2.0 4.5 1.08 1.16