ELSEVIER www.elsevier.com/locate/pnucene Progress in Nuclear Energy; gol. 47, No. 1-4, pp. 389-396, 2005 Available online at www.sciencedirect.com © 2005 Elsevier Ltd. All rights reserved s =, E N c E ~d) o,. E c v ° Printed in Great Britain 0149-1970/$ - see front matter doi: 10.1016/j.pnneene.2005.05.038 STUDIES OF LASER INDUCED CESIUM AND RUBIDIUM HYDRIDE FORMATION IN VAPOR CELLS AND THEIR APPLICATION FOR ISOTOPE SEPARATION A.BADALYAN 1 , V. CHALTYKYAN 1 , YASUHIKO FUJII 1, Yu.MALAKYAN 1 , MASAKI OZAWA 2'3, A.PAPOYAN 1, and S. SHMAVONYAN 1 1Institute for Physical Research, National Academy of Sciences, Armenia 2Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Japan 30-arai Engineering Center, Japan Nuclear Cycle Development Institute ABSTRACT We present the results of studies of alkali hydride formation in vapor cells under laser irradiation. Two mechanisms are studied: formation in the cell volume in the presence of hydrogen and formation on the laser irradiated cell window. The first mechanism is investigated in a room-temperature cesium vapor cell, while the second one in a heated natural rubidium cell. The studies are aimed at isotope separation by means of selective laser excitation of the vapor with subsequent hydride formation. In the first case we obtained the intensity dependence of the absorption and fluorescence and could evaluate, by comparing with calculations, the rate constant of the two-step reaction of CsH formation. In the second case a solid layer deposition was observed on the cell window and interpreted as rubidium hydride. © 2005 Elsevier Ltd. All rights reserved KEYWORDS Isotope separation; Alkali hydrides; Vapor cells; Selective excitation; Photochemical reactions 1. INTRODUCTION In many fields of science and technology often a need arises in materials consisting of a single isotope or enriched with that. This need is currently industrially satisfied by mainly two techniques of 389