کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1823796 | 1526441 | 2012 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: The Jefferson Lab frozen spin target The Jefferson Lab frozen spin target](/preview/png/1823796.png)
A frozen spin polarized target, constructed at Jefferson Lab for use inside a large acceptance spectrometer, is described. The target has been utilized for photoproduction measurements with polarized tagged photons of both longitudinal and circular polarization. Protons in TEMPO-doped butanol were dynamically polarized to approximately 90% outside the spectrometer at 5 T and 200–300 mK. Photoproduction data were acquired with the target inside the spectrometer at a frozen-spin temperature of approximately 30 mK with the polarization maintained by a thin, superconducting coil installed inside the target cryostat. A 0.56 T solenoid was used for longitudinal target polarization and a 0.50 T dipole for transverse polarization. Spin-lattice relaxation times as high as 4000 h were observed. We also report polarization results for deuterated propanediol doped with the trityl radical OX063.
Journal: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment - Volume 684, 21 August 2012, Pages 27–35