Speaker
Weizhi Xiong
(Duke University)
Description
In order to investigate the proton radius puzzle, the PRad experiment (E12-11-106) [1] was performed in 2016 in Hall B at Jefferson Lab, with both 1.1 and 2.2 GeV unpolarized electron beams. The experiment aims to measure the $e$-$p$ elastic scattering cross section at unprecedented low values of the momentum transfer squared region ($Q^2 = 2\times10^{-4} - 0.06$ (GeV/c)$^2$), with a sub-percent precision. The PRad experiment utilizes a non-magnetic calorimetric method with a large acceptance and high resolution calorimeter (HyCal), and two large area, high spatial resolution Gas Electron Multiplier (GEM) detectors. To have a better control over the systematic uncertainties, the absolute $e$-$p$ elastic scattering cross section is normalized to that of the well-known Moller scattering process, which is measured simultaneously within similar kinematics and geometrical acceptances. The windowless H$_2$-gas-flow target utilized in the experiment largely removes a typical background source, the target cell windows. In this talk, we will discuss details of the data analysis and present preliminary results from both beam energy settings.
[1] Spokespersons: A. Gasparian (contact), H. Gao, M. Khandaker, D. Dutta.
| [email protected] | |
| Collaboration name | PRad Collaboration |
| Funding source | Supported in part by the U.S. Department of Energy under Contract No. DE-FG02-03ER41231, NSF MRI award PHY-1229153 |
Primary author
Weizhi Xiong
(Duke University)
Co-author
Mr
Chao Peng
(Duke University)
