t o p i c c o m p o s i t i o n of t h e p l u m e c o m ponents. In other applications by m a t c h i n g t h e v o l u m e of s a t u r a t e d R I S photoionization to the acceptance i m a g e - p l a n e of a m a s s a n a l y z e r , o n e c a n o b t a i n e l e m e n t a l s p e c i f i c i t y in ionization a n d t h e n achieve isotopic s e p a r a t i o n in t h e m a s s a n a l y z e r . T h i s r e l a t i v e l y n e w a r e a of s t u d y is b e i n g p u r s u e d presently. Again, b a c k g r o u n d m a s s a n a l y z e r effects c a n b e i m p r o v e d o r d e r s of m a g n i t u d e b y t i m e g a t i n g t h e mass detection to t h e R I S laser pulse.
References (1) G. S. Hurst, M. G. Payne, M. H. Nayfeh, J. P. Judish, and Ε. Β. Wagner, Phys. Rev. Lett., 35, 82 (1975). (2) G. S. Hurst, M. G. Payne, S. D. Kram er, and J. P. Young, Rev. Mod. Phys., in press. (3) G. S. Hurst, M. H. Nayfeh, and J. P. Young, Appl. Phys. Lett., 30, 229 (1977). (4) G. S. Hurst, M. H. Nayfeh, and J. P. Young, Phys. Rev. A, 15, 2283 (1977). (5) S. D. Kramer, J. P. Young, G. S. Hurst, and M. G. Payne, Opt. Commun., in press. (6) G. C. Bjorklund, C. P. Ausschnitt, R. R. Freeman, and R. H. Stortz, Appl. Phys. Lett., 33,54(1978). (7) Santos Mayo and Thomas Lucartorto, private communication (1978). (8) G. I. Bekov, V. S. Letokhov, and V.
I. Mishin, Sov. Phys.-JETP, 2 1 , 52 (1978). (9) T. A. Calcott, D. Beekman, S. D. Kramer, Ε. Τ. Arakawa, and G. S. Hurst, to be published. (10) R. V. Ambartsumyan, V. N. Kalinin, and V. S. Letokhov, Zh. Ek.sp. Teor. Fiz. Pis'maRed., 13(6), 305 (1977). (11) R. V. Ambartsumyan, and V. S. Leto khov, Appl. Opt., 11(2), 354 (1972). (12) L. W. Grossman, G. S. Hurst, M. G. Payne, and S. L. Allman, Chem. Phys. Lett., 50,70(1977). (13) L. W. Grossman, G. S. Hurst, S. D. Kramer, M. G. Payne, and J. P. Young, Chem. Phys. Lett., 50, 207 (1977). (14) G. I. Bekov, V. S. Letokhov, O. I. Matveev, and V. I. Mishin, Opt. Lett., 3, 159 (1978). (15) G. W. Greenlees, D. L. Clark, S. L. Kaufman, D. A. Lewis, J. F. Tonn, and J. H. Broadhurst, Opt. Commun., 23, 236 (1977). (16) S. D. Kramer, C. Ε. Bemis, Jr., J. P. Young, and G. S. Hurst, Opt. Lett., 3,16 (1978). (17) G. S. Hurst, S. L. Allman, M. G. Payne, K. A. Marshall, and K. L. SooHoo, Nucl. Instrum. Methods, 155, 203 (1978). (18) G. S. Hurst, S. L. Allman, M. G. Payne, and T. J. Whitaker, Chem. Phys. Lett., in press. (19) C. J. Borkowski, and M. K. Kopp, Rev. Sci. Instrum., 39,1515 (1968). Oak Ridge National Laboratory is operated lor the U.S. Department of Energy by Union Carbide Corporation under Contract W-7405-eng-26. This article was supported by the U.S. Department of Energy.
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From left are J. P. Young, G. S. Hurst, in front of the Van de Graaff generator with He
M. G. Payne, and S. D. Kramer, that was used in the first RIS
standing experiment
Dr. Young is a research staff member of the Analytical Chemistry Diuision at ORNL. His research interests include applications of lasers to chemical analy sis and application of spectral and related techniques to the study of the chemical and physical properties of the transuranium elements and their progeny Dr. Hurst is head of the Photophysics group and Drs. Kramer and Payne are members, of that group which is in the Chemical Physics section at ORNL. Their research interests are in the areas of laser spectroscopy instrumentation, quantum optics, chemical kinetics, and one-atom detection 1060 A • ANALYTICAL CHEMISTRY, VOL. 51, NO. 11, SEPTEMBER 1979
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