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

verfasst von

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.

Externe Organisation(en)

Ruprecht-Karls-Universität Heidelberg
Karlsruher Institut für Technologie (KIT)

Typ

Artikel

Journal

Zeitschrift für Physik

Band

262

Seiten

189-210

Anzahl der Seiten

22

ISSN

1434-6001

Publikationsdatum

06.1973

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Kern- und Hochenergiephysik, Physik und Astronomie (insg.)

Elektronische Version(en)

https://doi.org/10.1007/BF01391836 (Zugang: Unbekannt)