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A positron moderator using porous metal

LOW ENERGY ACCELERATOR, RAY TECHNOLOGY AND APPLICATIONS

A positron moderator using porous metal

WANG Bao-yi
YU Run-sheng
ZHAO Fa-ru
MA Chuang-xin
ZHANG Tian-bao
WEI Long
Nuclear Science and TechniquesVol.15, No.4pp.213-215Published in print 01 Aug 2004
19800

Two types of porous metal moderators (i.e. porous nickel layer and multi-wire tungsten layer) are proposed and tested on a slow positron beam line. A moderation efficiency of about 2×10-4 has been achieved, which is higher than that for W vane geometry moderator by a factor of 4.

Slow positron beamModeratorPorous metal
References
[1] Schultz J, Lynn K G.. Rev Mod Phys, 1988, 60: 701
[2] Wang J C, You F Q, Yin J L et al. Nucl Sci Tech, 2001, 12(1): 40
[3] Krause-Rehberg R, Leipner H S. Positron annihilation in semiconductors, Berlin: Springer-Verlag, 1999
[4] Pendyala S, McGowan J W. J Electron Spectrosc Relat Phenom, 1980, 19: 161
[5] Hulett L D, Dale J M, Pendyala S. in Coleman P G, Sharma S C, Diana L M (ed.), Positron annihilation, Amsterdam: North-Holland, 1982: 857
[6] Khatri R, Charlton M, Sferlazzo P et al. Appl Phys Lett, 1990, 57: 2374
[7] Mills A P J, Gullikson E M. Appl Phys Lett, 1986, 49: 1121
[8] Brauer G, Anwand W, Nicht E M. Appl Surf Sci, 1997, 116: 19
[9] Stormer J, Goodyear A, Anwand W et al. J Phys: Condens Matter, 1996, 8: L89
[10] Yu R S, Wei L, Wang B Y et al. Nucl Instr Meth Phys Res, 2001, A457: 419
[11] Kobayashi Y, Kojima I, Hishita S et al. Phys Rev, 1995, B52: 823
[12] Beling C D, Simpson R I, Charlton M. Appl Phys, 1987, A42: 111