Exclusive K⁺Λ and K⁺Σ⁰ electroproduction at Q²≅0.5 (GeV/c)²

We measured the differential cross section for the p(e,e'K⁺)Λ/Σ⁰ reaction at Jefferson Lab in 2018 [1,2]. This dataset is at four-momentum transfer Q²≅0.5 (GeV/c)² ,W≅2.14 GeV, θ_γK^c.m.≅8 deg. This kinematic condition has never been covered by other experiments. In this talk, we will report the differential cross section for the extracted virtual photoproduction, p(γ*,K⁺)Λ/Σ⁰ reaction, to compare with the photoproduction.

The new results were compared with predictions of isobaric models which describe the hyperon production reaction with hadron degrees of freedom. In particular, BS models [3] developed by Bydžovský and Skoupil were optimized with extensive photoproduction experimental data reported by CLAS and LEPS in 2010 and 2006, respectively.The predictions of the hyperon elecetroproduction with the models were in good agreement with our new results. According to the BS models, the longitudinal couplings of the virtual photon had a significant contribution. This cannot be investigated by the photoproduction, but can be approached only by the electroproduction. Our new results can help to determine the magnitude of the longitudinal couplings at relatively high-Q² region.

[1] B. Panday et al., PRC 105 (2022) L051001.

[2] K.N. Suzuki et al., PTEP 013D01 (2022).

[3] D. Skoupil and P. Bydžovský, PRC 93 (2016) 025204; PRC 97 (2018) 025202.