Publications
Publication Information
| Title | The PRad Windowless Gas Flow Target |
| Authors | Josh Pierce, James Brock, Christopher Keith, James Maxwell, David Meekins, Xinzhan Bai, Alexandre Deur, Dipangkar Dutta, Haiyan Gao, Ashot Gasparian, Kondo Gnanvo, Chao Gu, Douglas Higinbotham, Mahbub Khandaker, Nilanga Liyanage, Mehdi Meziane, Eugene Pasyuk, C. Peng, Vina Punjabi, Weizhi Xiong, X. Yan, Li Ye, Yang Zhang, Christopher Carlin |
| JLAB number | JLAB-PHY-21-3330 |
| LANL number | arXiv:2103.01749 |
| Other number | DOE/OR/23177-5169 |
| Document Type(s) | (Journal Article) |
| Associated with EIC: | No |
| Supported by Jefferson Lab LDRD Funding: | No |
| Funding Source: | Nuclear Physics (NP) |
|
Journal Compiled for Nuclear Instruments & Methods in Physics Research, Section A Volume in press Refereed | |
| Publication Abstract: | We report on a windowless, high-density, gas flow target at Jefferson Lab that was used to measure $r_p$, the root-mean-square charge radius of the proton. To our knowledge, this is the first such system used in a fixed-target experiment at a (non-storage ring) electron accelerator. The target achieved its design goal of an areal density of 2$\times$10$^{18}$ atoms/cm$^2$, with the gas uniformly distributed over the 4~cm length of the cell and less than 1\% residual gas outside the cell. This design eliminated scattering from the end caps of the target cell, a problem endemic to previous measurements of the proton charge radius in electron scattering experiments, and permitted a precise, model-independent extraction of $r_p$ by reaching unprecedentedly low values of $Q^2$, the square of the electron's transfer of four-momentum to the proton. |
| Experiment Numbers: | E12-11-106 |
| Group: | Cryo/Polarized Targets |
| Document: | |
| DOI: | https://doi.org/10.1016/j.nima.2021.165300 |
| Accepted Manuscript: | 1-s2.0-S0168900221002849-main.pdf |
| Supporting Documents: | |
| Supporting Datasets: | |