Precision Electron-Beam Polarimetry at 1 GeV Using Diamond Microstrip Detectors
Name
PhysRevX.6.011013.pdf
Size
864.7 KB
Format
Adobe PDF
Checksum (MD5)
77e81b46227654502c31c3b35c37406f
Author(s)
Narayan, A.
Jones, D.
Cornejo, J. C.
Dalton, M. M.
Deconinck, W.
Dutta, D.
Gaskell, D.
Martin, J. W.
Paschke, K. D.
Tvaskis, V.
Date Issued
February 2016
Journal
Physical Review X
Publisher
American Physical Society
Citation
Narayan, A., D. Jones, J. C. Cornejo, M. M. Dalton, W. Deconinck, D. Dutta, D. Gaskell, et al. “Precision Electron-Beam Polarimetry at 1 GeV Using Diamond Microstrip Detectors.” Physical Review X 6, no. 1 (February 16, 2016).
Version
Final published version
Abstract
We report on the highest precision yet achieved in the measurement of the polarization of a low-energy, O(1 GeV), continuous-wave (CW) electron beam, accomplished using a new polarimeter based on electron-photon scattering, in Hall C at Jefferson Lab. A number of technical innovations were necessary, including a novel method for precise control of the laser polarization in a cavity and a novel diamond microstrip detector that was able to capture most of the spectrum of scattered electrons. The data analysis technique exploited track finding, the high granularity of the detector, and its large acceptance. The polarization of the 180-μA, 1.16-GeV electron beam was measured with a statistical precision of <1% per hour and a systematic uncertainty of 0.59%. This exceeds the level of precision required by the Q[subscript weak] experiment, a measurement of the weak vector charge of the proton. Proposed future low-energy experiments require polarization uncertainty <0.4%, and this result represents an important demonstration of that possibility. This measurement is the first use of diamond detectors for particle tracking in an experiment. It demonstrates the stable operation of a diamond-based tracking detector in a high radiation environment, for two years.
MIT Department
Bates Linear Accelerator Center
Massachusetts Institute of Technology. Department of Physics
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1103/PhysRevX.6.011013
