Skip to main content
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.
/content/aip/journal/jap/118/10/10.1063/1.4930033
1.
1. Anwand, W. , J. M. Johnson, M. Butterling, A. Wagner, W. Skorupa, and G. Brauer, “ Flash lamp annealing of tungsten surfaces marks a new way to optimized slow positron yields,” J. Phys.: Conf. Ser. 443, 012072 (2013).
http://dx.doi.org/10.1088/1742-6596/443/1/012072
2.
2. Brandt, W. and R. Paulin, “ Positron implantation-profile effects in solids,” Phys. Rev. B 15, 2511 (1977).
http://dx.doi.org/10.1103/PhysRevB.15.2511
3.
3. Brusa, R. S. , M. D. Naia, E. Galvanetto, P. Scardi, and A. Zecca, “ Tungsten singlecrystal and polycrystalline foils used as first transmission moderator,” Mater. Sci. Forum 105, 1849 (1992).
http://dx.doi.org/10.4028/www.scientific.net/MSF.105-110.1849
4.
4. Coleman, P. G. et al., Positron Beams and their Applications ( World Scientific, Singapore, 2000), 116.
5.
5. Gullikson, E. M. and A. P. Mills, “ Positron dynamics in rare-gas solids,” Phys. Rev. Lett. 57(3), 376 (1986).
http://dx.doi.org/10.1103/PhysRevLett.57.376
6.
6. Gramsch, E. , J. Throwe, and K. G. Lynn, “ Development of transmission positron moderators,” Appl. Phys. Lett. 51(22), 1862 (1987).
http://dx.doi.org/10.1063/1.98495
7.
7. Greaves, R. G. and C. M. Surko, “ Solid neon moderator for positron-trapping experiments,” Can. J. Phys. 74(7–8), 445 (1996).
http://dx.doi.org/10.1139/p96-063
8.
8. Jacobsen, F. M. , M. Charlton, J. Chevallier, B. I. Deutch, G. Laricchia, and M. R. Poulsen, “ The effect of laser annealing of thin W(100) films on positron transmission reemission properties,” J. Appl. Phys. 67, 575 (1990).
http://dx.doi.org/10.1063/1.345197
9.
9. Kövér, Á. , D. J. Murtagh, A. I. Williams, and G. Laricchia, “ Differential ionization studies by positron impact,” J. Phys.: Conf. Ser. 199, 012020 (2010).
10.
10. Kövér, Á. , D. J. Murtagh, A. I. Williams, S. E. Fayer, and G. Laricchia, “ Electrostatic brightness enhanced positron beam,” Meas. Sci. Technol. 25, 075013 (2014).
http://dx.doi.org/10.1088/0957-0233/25/7/075013
11.
11. Lee, K. H. , Y. Itoh, I. Kanazawa, N. Ohshima, T. Nakajou, and Y. Ito, “ Practical usage of a W moderator for slow positron beam production,” Phys. Status Solidi A 157, 93 (1996).
http://dx.doi.org/10.1002/pssa.2211570112
12.
12. Lynn, K. G. , B. Nielsen, and J. H. Quateman, “ Development and use of a thin-film transmission positron moderator,” Appl. Phys. Lett. 47, 239 (1985).
http://dx.doi.org/10.1063/1.96231
13.
13. Massoumi, G. R. , P. J. Schultz, W. N. Lennard, and J. Ociepa, “ Positron emission yields for encapsulated 22Na sources,” Nucl. Instrum. Methods Phys. Res. B 30, 592 (1988).
http://dx.doi.org/10.1016/0168-583X(88)90136-X
14.
14. Massoumi, G. R. , N. Hozhabri, W. N. Lennard, P. J. Schultz, S. F. Baert, H. H. Jorch, and A. H. Weiss, “ Rare gas moderated electrostatic positron beam,” Rev. Sci. Instrum. 62, 1460 (1991).
http://dx.doi.org/10.1063/1.1142467
15.
15. Mills, A. P. , “ Brightness enhancement of slow positron beams,” Appl. Phys. A 23, 189 (1980).
http://dx.doi.org/10.1007/BF00899716
16.
16. Mills, A. P. and E. M. Gullikson, “ Solid neon moderator for producing slow positrons,” Appl. Phys. Lett. 49(17), 1121 (1986).
http://dx.doi.org/10.1063/1.97441
17.
17. Mourino, M. , H. Löbl, and R. Paulin, “ Profiles and absorption coefficients of positrons implanted in solids from radioactive sources,” Phys. Lett. A 71A, 106 (1979).
http://dx.doi.org/10.1016/0375-9601(79)90890-9
18.
19. Reurings, F. , A. Laakso, K. Rytsola, A. Pelli, and K. Saarinen, “ Compact positron beam for measurement of transmission moderator efficiencies and positron yields of encapsulated sources,” Appl. Surf. Sci. 252, 3154 (2006).
http://dx.doi.org/10.1016/j.apsusc.2005.08.066
19.
20. Saito, F. , Y. Nagashima, L. Wei, Y. Itoh, A. Goto, and T. Hyodo, “ A high-efficiency positron moderator using electro-polished tungsten meshes,” Appl. Surf. Sci. 194, 13 (2002).
http://dx.doi.org/10.1016/S0169-4332(02)00103-4
20.
21. Schultz, P. J. and K. G. Lynn, “ Interaction of positron beams with surfaces, thin films, and interfaces,” Rev. Mod. Phys. 60, 701 (1988).
http://dx.doi.org/10.1103/RevModPhys.60.701
21.
22. Vehanen, A. and J. Mäkinen, “ Thin films for slow positron generation,” Appl. Phys. A: Solids Surf. 36(2), 97 (1985).
http://dx.doi.org/10.1007/BF00620615
22.
23. Vehanen, A. , K. G. Lynn, P. J. Schultz, and M. Eldrup, “ Improved slow-positron yield using a single crystal tungsten moderator,” Appl. Phys. A: Solids Surf. 32, 163 (1983).
http://dx.doi.org/10.1007/BF00616613
23.
24. Weng, H. M. , C. C. Ling, C. D. Beling, S. Fung, C. K. Cheung, P. Y. Kwan, and I. P. Hui, “ Tungsten mesh as positron transmission moderator in a monoenergetic positron beam,” Nucl. Instrum. Methods Phys. Res., Sect. B 225, 397 (2004).
http://dx.doi.org/10.1016/j.nimb.2004.05.002
24.
25. Williams, A. I. , Á. Kövér, D. J. Murtagh, and G. Laricchia, “ Progress towards a positron reaction microscope,” J. Phys.: Conf. Ser. 199, 012025 (2010).
25.
26. Zafar, N. , G. Laricchia, M. Charlton, and A. Garner, “ Positronium-argon scattering,” Phys. Rev. Lett. 76(10), 1595 (1996).
http://dx.doi.org/10.1103/PhysRevLett.76.1595
26.
27. Zafar, N. , J. Chevallier, F. M. Jacobsen, M. Charlton, and G. Laricchia, “ Experimentation with thin single crystal W foils as slow positron transmission mode moderators,” Appl. Phys. A: Mater. Sci. Process. 47(4), 409 (1988).
http://dx.doi.org/10.1007/BF00615506
http://aip.metastore.ingenta.com/content/aip/journal/jap/118/10/10.1063/1.4930033
Loading
/content/aip/journal/jap/118/10/10.1063/1.4930033
Loading

Data & Media loading...

Loading

Article metrics loading...

/content/aip/journal/jap/118/10/10.1063/1.4930033
2015-09-09
2016-09-30

Abstract

The efficiency of tungsten meshes and thin foils for moderation of fast positrons from 22 Na has been investigated in transmission geometry and a fair agreement has been found with previous experimental results where directly comparable. For foils, the dependence on material thickness is found to be similar to the prediction of the Vehanen-Mäkinen diffusion model; however, the magnitude is 5–10 times lower. A broad consensus is observed between experiment and the results of a three-dimensional model developed in this work. For a given thickness, meshes are found to be generally better than foils by around a factor of 10 with a maximum efficiency ( 10−3) comparable to that achieved with thin single crystal foils, in accord with previous measurements and the results of the present model.

Loading

Full text loading...

/deliver/fulltext/aip/journal/jap/118/10/1.4930033.html;jsessionid=gIM9ZNX19PIUQPv-1QEusfrX.x-aip-live-06?itemId=/content/aip/journal/jap/118/10/10.1063/1.4930033&mimeType=html&fmt=ahah&containerItemId=content/aip/journal/jap
true
true

Access Key

  • FFree Content
  • OAOpen Access Content
  • SSubscribed Content
  • TFree Trial Content
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
/content/realmedia?fmt=ahah&adPositionList=
&advertTargetUrl=//oascentral.aip.org/RealMedia/ads/&sitePageValue=jap.aip.org/118/10/10.1063/1.4930033&pageURL=http://scitation.aip.org/content/aip/journal/jap/118/10/10.1063/1.4930033'
Right1,Right2,Right3,