Search

We consider pion electroproduction close to threshold for Q2 in the region 1–10 GeV2 on a nucleon target. The momentum transfer dependence of the S-wave multipoles at threshold, E0+ and L0+, is calculated in the chiral limit using light-cone sum rules. Predictions for the cross sections in the threshold region, both for π0p and π+n channels, are given that include P-wave contributions that, as we argue, are model independent to a large extent. The results are compared with the SLAC E136 data on the structure function F2(W,Q2) in the threshold region. [ABSTRACT FROM AUTHOR]

We present the effects of Fermi motion and different off-shell assumptions on the differential cross sections of photo- and electroproduction of the hypertriton. We found that Fermi motion plays an important role in these processes. Different off-shell assumptions yield different cross section magnitudes. The few available electroproduction data favor the assumption that the initial nucleon is off-shell and the final hyperon is on-shell. Measurement of the hypertriton photoproduction is urgently required to further support our findings. [ABSTRACT FROM AUTHOR]

We show that we are able to extract the pion electromagnetic form factor by using the recent charged pion electroproduction data from JLab and a simple t-channel diagram. For this purpose we have performed the Q2-independent and dependent analyses. The result of the first analysis is in good agreement with those of previous works and fit the Maris and Tandy model as well as the monopole parametrization which describes a pion radius of 0.672 fm. The result of the second analysis corroborates the findings in the first analysis. Our findings therefore provide a direct proof that at the given kinematics the t-channel diagram really dominates the process. This could also set a new constraint to the phenomenological models that try to describe the process. [ABSTRACT FROM AUTHOR]