Speaker
Description
The ULQ2 (Ultra Low Q2) experiment at ELPH is aiming at determining the proton charge radius with the electron scattering. The features of the ULQ2 experiment are as follows: absolute cross section measurement with very high accuracy of 0.001 using relative measurement of e+p and e+C, measurement at extremely low momentum transfer region of 0.0003 ≤ Q2 ≤ 0.008 (GeV/c)2 with lowest-ever beam energies of 10 - 60 MeV, and experimental separation of charge and magnetic form factor (Rosenbluth separation). Such measurements can remove model dependence as much as
possible and obtain the most reliable proton radius for electron
scattering.
A new beam line and spectrometers specially designed for the
low-energy electrons scattering have been constructed, and
commissioning is ongoing for physics run starting in FY2022. In this talk, the details and preparation status of the ULQ2 experiments will be presented.
