World Academy of Science, Engineering and Technology
Published October 1, 2015 | Version 10002815
Journal article Open

Interaction of Low-Energy Positrons with Mg Atoms: Elastic Scattering, Bound States, and Annihilation

Description

Annihilations, phase shifts, scattering lengths and elastic cross sections of low energy positrons scattering from magnesium atoms were studied using the least-squares variational method (LSVM). The possibility of positron binding to the magnesium atoms is investigated. A trial wave function is suggested to represent e+-Mg elastic scattering and scattering parameters were derived to estimate the binding energy and annihilation rates. The trial function is taken to depend on several adjustable parameters, and is improved iteratively by increasing the number of terms. The present results have the same behavior as reported semi-empirical, theoretical and experimental results. Especially, the estimated positive scattering length supports the possibility of positronmagnesium bound state system that was confirmed in previous experimental and theoretical work.

Files

10002815.pdf

Files (278.6 kB)

Name Size
md5:6c13cb13eee95135d2a3dd607cea830c
278.6 kB Preview Download

Additional details

References

  • K. Fedus and G.P. Karwasz, Acta Physica Polonica A. Vol. 125, 3, 2014.
  • J. R. Danielson, A. C. L. Jones, M. R. Natisin, and C. M. Surko, Phys. Rev. A 88, 062702, 2013.
  • M W J Bromley, J Mitroy and G Ryzhikh, J. Phys. B: At. Mol. Opt. Phys. 31, 4449–4458, 1998.
  • Surko C M and Greaves R G Phys. Plasmas (11) 2333, (2004).
  • C. M. Surko, G. F. Gribakinand S. J. Buckman Journ. Phys. B: At. Mol. Opt. Phys. 38, R57-R126, (2005).
  • Hulett L D, Donohue D L, Xu J, Lewis T A, McLuckey S A and Glish G L Chem. Phys. Lett. 216, 236, 1993.
  • J. P. Peng et al., Phys. Rev. Lett. 76, 2157 1996.
  • Kurtz H A and Jordan K D. J. Phys. B: At. Mol. Phys. 14, 4361, 1981.
  • Szmytkowski R J. Physique II 3, 183, 1993. [10] Ryzhikh G G, Mitroy J and Varga K J. Phys. B: At. Mol. Opt. Phys. 31, 3965, 1998. [11] Hewitt R N, Noble C J, Bransden B H and Joachain C J Can. J. Phys. 74, 559, 1996. [12] C M Surko, J R Danielson, G F Gribakin, and R E Continetti G, New Journal of Physics 14, 65004, 2012. [13] V. A. Dzuba and V.V. Flambaum, Physical Review Letters, PRL 105, 203401, 2010. [14] M.A. Abdel-Raouf, Phys.Rep.108 pp1-164 1984. [15] M. M. Abdel-Mageed, M. Abdel-Aziz, and H.S. Zaghloul, AIP Conference Proceedings. 888, 358-365, 2007. [16] Mahasen M. Abdel-Mageed, Brazilian Journal of Physics, vol. 40, no. 1, March, 2010. [17] Ali H. Moussa, G. M. Mostafa and Atef Khazbak, J. Quant. Spect. and Rad. Tran., 77, Issue 2, 225-230, 2003. [18] M.A.El-Aasar, M.A. and Abdel-Raouf, J. Phys. B: At. Mol. Phys 40, 1801-1819, 2007. [19] M W J Bromley, J Mitroy and G Ryzhikh J. Phys. B: At. Mol. Opt. Phys. 31 4449–4458, 1998. [20] Robert D.Cowan, "The Theory of Atomic Structure and Spectra Univ. of California Press, 1981; Phys.Rev.163, 54, 1967. [21] E. W. Schmid and K.H. Hoffmann, Nucl.Phys.A175, 443, 1971. [22] E. W. Schmid, Nucl. Phys. A180, 434 1972; Nuovo Cim. A18, 171, 1973. [23] J Mitroy, M W J Bromley and G G Ryzhikh, J. Phys. B: At.Mol. Opt. Phys. 35 R81–R116, 2002. [24] V. A. Dzuba, V. V. Flambaum, G. F. Gribakin, and W. A. King, Physical Review A, 52:4541–4546, 1995. [25] G. G. Ryzhikh and J. Mitroy, Physical Review Letters, 79, 4124-4126, 1997. [26] J. Mitroy, M W J Bromley, and G G Ryzhikh. Journal of Physics B, 35:R81, 2002. [27] J. Mitroy and I. A. Ivanov, Phys.Rev. A65, 42705 2002. [28] G. F. Gribakin W.A. King Can. J. Phys 74, 449-454 1996 [29] T. S. Stein, M. Harte, J. Jiang, W. E. Kauppila, C. K. Kwan, H. Li, and S. Zhou, Nucl. Instrum. Methods Phys. Res. B 143, 68, 1998. [30] J. W. Humberston Adv. At. Mol. Phys. 15, 101, 1979. [31] P. A. Fraser, Adv. At. Mol. Phys. 4, 63, 1968.