Relaxation and deorientation of¹¹⁰Ag(T_1/2=24.4s) nuclei produced by capture of polarized neutrons in the silver halides

authored by

J. Mertens, H. Ackermann, D. Dubbers, P. Heitjans, A. Winnacker, P. von Blanckenhagen

Abstract

Polarized¹¹⁰Ag nuclei are produced in the silver halides by capture of polarized neutrons at temperatures below 30 K and magnetic field strengths up to 6 kOe. The depolarization process is studied by observation of the β decay asymmetry as a function of magnetic field, temperature and of the radio frequency field strength in NMR signals. The depolarization is caused by a field dependent deorientation process and by temperature dependent spin-lattice relaxation. The deorientation is due to a succession of coupling steps of the nuclear spin with electromagnetic fields of defects generated as a consequence of the capture process, and the field dependence of the polarization can be understood as a decoupling curve. The temperature dependence of the spin-lattice relaxation is in accordance with the theory of quadrupolar relaxation above 18 K if an empirical phonon spectrum is used for the calculation. At lower temperatures the experimental relaxation rate is anomalously high, which may be due to resonance modes connected with recoil lattice defects.

External Organisation(s)

Heidelberg University
Karlsruhe Institute of Technology (KIT)

Type

Article

Journal

Zeitschrift für Physik

Volume

262

Pages

189-210

No. of pages

22

ISSN

1434-6001

Publication date

06.1973

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Nuclear and High Energy Physics, General Physics and Astronomy

Electronic version(s)

https://doi.org/10.1007/BF01391836 (Access: Unknown)