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HK: Physik der Hadronen und Kerne

HK 42: Instrumentation and Applications V

HK 42.4: Vortrag

Donnerstag, 14. März 2002, 15:00–15:15, F

Nuclear Polarization of Molecular Hydrogen — •F. Rathmann¹, J.T. Balewski², J. Doskow², W. Haeberli³, B. Lorentz¹, H.O. Meyer², P.V. Pancella⁴, R.E. Pollock², B. v. Przewoski², P.A. Quin³, T. Rinckel², Swapan K. Saha⁵, B. Schwartz³, T.G. Walker³, A. Wellinghausen², and T. Wise³ — ¹IKP, FZJ, Jülich, Germany — ²IUCF, Bloomington, USA — ³Dep. of Physics, University of Wisconsin-Madison, USA — ⁴Western Michigan University, Kalamazoo, USA — ⁵Bose Institute, Calcutta, India

We have measured the nuclear polarization of hydrogen molecules formed by recombination of polarized atomic hydrogen gas [1]. A polarized atomic hydrogen beam is incident upon a copper recombination zone and subsequently drifts into an internal target located in a straight section of the IUCF Cooler ring. The target contains an internal valve that allows us to rapidly alternate between a mostly atomic and a mostly molecular target. A comparison of the target polarization for these two states can be used to determine the fraction of the initial atom polarization that survives recombination and subsequent wall collisions in the target. That fraction was studied for temperatures between 50 K and 300 K and for applied magnetic fields between 0.5 mT and 0.6 T. The target polarization was measured with a 200 MeV longitudinally polarized proton beam using the known [2] large pp elastic spin correlation coefficient A_zz. The apparatus, measurement methods, results and interpretation will be descussed.

[1] T. Wise et al., Phys. Rev. Lett. 87, 042701 (2001).

[2] B. Lorentz et al., Phys. Rec. C 61 54002(2000).