Ionization Efficiency in a Hot Flat Disc-Shaped Cavity
https://doi.org/10.21122/2220-9506-2020-11-2-132-139
Abstract
Hot cavity ion sources of different kinds are widely used in nuclear and mass spectroscopy, especially in on-line isotope separation devices attracting attention of scientists and engineers looking for high ionization efficiency, robustness and beam purity. In the paper a new type of hot ionizer cavity is proposed: namely cavity having the shape of a flat disc, which may be especially suitable for short-lived nuclides to be ionized.
A numerical model of the ion source is presented in the paper. The particle tracking code takes into account ionization at hot surfaces and enables modeling of both flat disc cavity and standard elongated cavity ionizers. The code enables calculation of total ionization efficiency and is suitable for stable and long-lived nuclides.
Influence of the flat disc cavity geometry (thickness and radius) and its temperature on total ionization efficiency was considered – it was shown that the efficiency increases with cavity radius due to the growing number of particle-wall collisions. This effect may be important in the case of the hard-to-ionize nuclides.
The optimal ionizer geometry is characterized by 90 % efficiency, even for substances with rather low ionization coefficient (of order 0.05). The role played by the size of the extraction opening is explained – it is demonstrated that the ionization efficiency increases due to the opening radius reduction. It is also proven that extraction voltage of 1–2 kV is sufficient to maintain optimal ionizer efficiency.
Supporting agencies: The research was cofunded by th Plenipotent Representative of the Government of the Republic of Poland at JINR Dubna in the frame of the project № 75/07/2020.
About the Author
M. Turek
Maria Curie-Sklodowska University in Lublin
Poland
Poland
Address for correspondence: M. Turek - Institute of Physics, Maria Curie-Sklodowska University in Lublin, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland e-mail: mturek@kft.umcs.lublin.pl
References
1. Studer D., Maske L., Windpassinger P., Wendt K. Laser spectroscopy of the 1001-nm ground-state transition in dysprosium. Phys. Rev. A, 2018, vol. 98, pp. 042504. DOI: https://doi.org/10.1103/PhysRevA.98.042504
2. Duan Y., Danen R.E., Yan X., Steiner R., Cuadrado J., Wayne D., Majidi V., Olivares J.A. Characterization of an improved thermal ionization cavity source for mass spectrometry. Journal of the American Society for Mass Spectrometry, 1999, vol. 10, pp. 917–1052. DOI: 10.1016/S1044-0305(99)00065-3
3. Maden C., Trinquier A., Fauré A.-L., Hubert A., Pointurier F., Rickli J., Bourdon B. Design of a prototype thermal ionization cavity source intended for isotope ratio analysis. International Journal of Mass Spectrometry, 2018, vol. 434, pp. 70–80. DOI: 10.1016/j.ijms.2018.09.006
4. Babcock C., Day Goodacre T., Gottberg A. Target and Ion Source Development for Better Beams in the ARIEL Era. IOP Conf. Series: Journal of Physics: Conf. Series, 2018, vol. 1067, pp. 052019. DOI: 10.1088/1742-6596/1067/5/052019
5. Alton G.D., Liu Y., Stracener D.W. High-efficiency target ion sources for radioactive ion beam generation. Rev. Sci. Instrum., 2006, vol. 77, pp. 03A711. DOI: 10.1063/1.2173968
6. Köster U., Arndt O., Bouquerel E., Fedoseyev V.N., Franberg H., Joinet A., Jost C., Kerkines I.S.K., Kirchner R. The TARGISOL Collaboration, Progress in ISOL target-ion-source-system. Nucl. Instrum Meth. B, 2008, vol. 266, pp. 4229–4239. DOI: 10.1016/j.nimb.2008.05.152
7. Woo H.J., Kang B.H., Tshoo K., Seo C.S., Hwang W., Park Y.H., Yoon J.W., Yoo S.H., Kim Y.K., Jang D.Y. Overview of the ISOL facility for the RISP. Journal of the Korean Physical Society, 2015, vol. 66, pp. 443–448. DOI: 10.3938/jkps.66.443
8. Beyer G.J., Herrmann E., Piotrowski A., Raiko V.I., Tyroff H. A new method for rare-earth isotope separation. Nucl. Instrum. Meth. 1971, vol. 96, pp. 437– 439. DOI: 10.1016/0029-554X(71)90613-6
9. Johnson P.G., Bolson A., Henderson C.M. A high temperature ion source for isotope separators. Nucl. Instrum. Meth., 1973, vol. 106, pp. 83–87. DOI: 10.1016/0029-554X(73)90049-9
10. Liu Y., Jost C.U., Mendez II A.J., Stracener D.W., Williams C.L., Gross C.J., Grzywacz R.K., Madurga M., Miernik K., Miller D. On-line commissioning of the HRIBF resonant ionization laser ion source. Nucl. Instrum. and Meth. B, 2013, vol. 298, pp. 5–12. DOI: 10.1016/j.nimb.2012.12.041
11. Lecesne N. Laser ion sources for radioactive beams. Rev. Sci. Instrum., 2012, vol. 83, pp. 02A916. DOI: 10.1063/1.3681148
12. Henares J.L., Lecesne N., Hijazi L., Bastin B., Kron T., Lassen J., Le Blanc F., Leroy R., Osmond B., Raeder S., Schneider F., Wendt K. Hot-cavity studies for the Resonance Ionization Laser Ion Source. Nucl Instr. Meth. B, 2016, vol. 830, pp. 520–525. DOI: 10.1016/j.nima.2015.10.061
13. Day Goodacre T., Billowes J., Catherall R., Cocolios T.E., Crepieux B., Fedorov D.V., Fedosseev V.N., Gaffney L.P., Giles T., Gottberg A., Lynch K.M., Marsh B.A., Mendonça T.M., Ramos J.P., Rossel R.E., Rothe S., Sels S., Sotty C., Stora T., Van Beveren C., Veinhard M. Blurring the boundaries between ion sources: The application of the RILIS inside a FEBIAD type ion source at ISOLDE. Nucl Instr. Meth. B, 2016, vol. 376, pp. 39–45. DOI: 10.1016/j.nimb.2016.03.005
14. Kalinnikov V.G., Gromov K.Ya., Janicki M., Yushkevich Yu.V., Potempa A.W., Egorov V.G., Bystrov V.A., Kotovsky N.Yu., Evtisov S.V. Experimental complex to study nuclei far from the beta-stability line – ISOL-facility YASNAPP-2. Nucl. Instr. and Meth. B, 1992, vol. 70, pp. 62–68. DOI: 10.1016/0168-583X(92)95910-J
15. Zhai L., Deng H., Wei G., Li Z., Wang C., Li X., Zhou G., Su Y., Zhang Z. A new, ohmic-heating based thermal ionization cavity source for mass spectrometry. International Journal of Mass Spectrometry, 2011, vol. 305, pp. 45–49. DOI: 10.1016/j.ijms.2011.05.015
16. Eléon C., Jardin P., Gaubert G., Saintlaurent M., Alcantaranunez J., Alvesconde R. Development of a surface ionization source for the production of radioactive alkali ion beams in SPIRAL. Nucl. Instr. and Meth. B, 2008, vol. 266, рр. 4362–4367. DOI: 10.1016/j.nimb.2008.05.067
17. Reponen M., Moore I.D., Pohjalainen I., Rothe S., Savonen M., Sonnenschein V., Voss A. An inductively heated hot cavity catcher laser ion source. Rev Sci Instrum. 2015, vol. 86, pp. 123501. DOI: 10.1063/1.4936569
18. Alton G.D., Zhang Y. A fast effusive-flow vaportransport system for ISOL-based radioactive ion beam facilities. Nucl. Instrum. and Meth. A, 2005, vol. 539, pp. 540–546. DOI: 10.1016/j.nima.2004.11.027
19. Alton G.D., Liu Y., Zaim H., Murray S.N. An efficient negative surface ionization source for RIB generation. Nucl. Instrum. and Meth. B, 2003, vol. 211, pp. 425–435. DOI: 10.1016/S0168-583X(03)01365-X
20. Hausladen P.A., Weisser D.C., Lobanov N.R., Fifield L.K., Wallace H.J. Simple concepts for ion source improvement. Nucl. Instrum. and Meth. B, 2002, vol. 190, pp. 402–404. DOI: 10.1016/S0168-583X(01)01307-6
21. Turek M., Pyszniak K., Drozdziel A., Sielanko J. Ionization efficiency calculations for cavity thermoionization ion source. Vacuum, 2008, vol. 82, pp. 1103–1106. DOI: 10.1016/j.vacuum.2008.01.025
22. Turek M., Pyszniak K., Droździel A. Influence of electron impact ionization on the efficiency of thermoemission ion source. Vacuum, 2009, vol. 83, pp. S260–S263. DOI: 10.1016/j.vacuum.2009.01.077
23. Turek M., Drozdziel A., Pyszniak K., Maczka D., Slowinski B. Simulations of ionization in a hot cavity surface ion source. Rev. Sci. Instrum., 2012, vol. 83, pp. 023303. DOI: 10.1063/1.3685247
24. Turek M. Modeling of Ionization in a Spherical Surface Ionizer. Acta Phys. Pol. A, 2011, vol. 120, pp. 188–191. DOI: 10.12693/APhysPolA.120.188
25. Turek M. Ionisation Efficiency in Conical Hot Cavities. Acta Phys. Pol. A, 2017, vol. 132, pp. 259–263. DOI: 10.12693/APhysPolA.132.259
26. Maden C., Baur H., Fauré A.-L., Hubert A., Pointurier F., Bourdon B. Determination of ionization efficiencies of thermal ionization cavity sources by numerical simulation of charged particle trajectories including space charge. Int. J. Mass Spectr., 2016, vol. 405, pp. 39–49. DOI: 10.1016/j.ijms.2016.05.013
27. Liu Y., Batchelder J.C., Galindo-Uribarri A., Chu R., Fan S., Romero-Romero E., Stracener D.W. Ion source development for ultratrace detection of uranium and thorium. Nucl. Instrum. and Meth. B, 2015, vol. 361, pp. 267–272. DOI: 10.1016/j.nimb.2015.04.081
28. Turek M. Ionization of short-lived isotopes in a hot cavity – Numerical simulations. Vacuum, 2014, vol. 104, pp. 1–12. DOI: 10.1016/j.vacuum.2013.12.016
29. Hadjidimos A. Successive overrelaxation (SOR) and related methods. Journal of Computational and Applied Mathematics, 2000, vol. 123, pp. 177–199. DOI: 10.1016/S0377-0427(00)00403-9
30. Press W.H., Teukolsky S.A., Vetterling W.T., Flannery B.P. Numerical recipes in FORTRAN (2nd ed.): The art of scientific computing, 1992, Cambridge University Press New York.
31. Latuszyński A., Mączka D. High temperature cavity thermo-ionizer. Vacuum, 1998, vol. 51, pp. 109– 112. DOI: 10.1016/S0042-207X(98)00142-0
Review
For citations:
Turek M. Ionization Efficiency in a Hot Flat Disc-Shaped Cavity. Devices and Methods of Measurements. 2020;11(2):132-139. https://doi.org/10.21122/2220-9506-2020-11-2-132-139
Views:
1744
Email this article 