Design and Simulation of a Trap-Based Pulsed Slow Positron Beam

Abstract:

A simple pulsed slow positron beam based on a Penning-trap has been designed and is being constructed in Wuhan University. The cooled positrons from the trap with very low energy dispersion are dumped and chopped to pulses of a few tens of ns in width. Positron pulses are bunched by adjusting the potential of drift tube using an arbitrary wave generator, then accelerated to the target. Influences of the pulse width, the energy dispersion of positrons etc. on the time resolution of bunched positron pulse are simulated. The result shows that lower energy dispersion of positrons leads to much narrower positron pulses, indicating that a trap-based slow positron beam has a great advantage in developing a pulsed slow positron beam.

• Periodical: Materials Science Forum (Volume 733)
• Pages: 314-317
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.733.314
• Online since: November 2012
• Authors: Chun Qing He, Jun Cheng Wang, Jun Zhu, Shao Jie Wang
• Keywords: Bunching, Energy Dispersion, Slow Positron Beam, Time Resolution, Trap

References

[1] P. Asoka-Kumar, K. G. Lynn and D. O. Welch, J. Appl. Phys. 76 (9) (1994), p.4935.

[2] P. G. Coleman, Appl. Surf. Phys. 194 (2002), pp.264-270.

[3] N. Oshima, R. Suzuki, T. Ohdaira, A. Kinomura, T. Narumi, A. Uedono and M. Fujinami, J. Appl. Phys. 103 (2008), p.094916.

DOI: 10.1063/1.2919783

[4] N. Oshima, R. Suzuki, T. Ohdaira, A. Kinomura, T. Narumi, A. Uedono and M. Fujinami, Appl. Phys. Lett. 94 (2009), p.194104.

DOI: 10.1063/1.3137188

[5] R. G. Greaves, AIP Conf. Proc. 606 (2002), pp.3-9.

[6] T. Itahashi, AIP Conf. Proc. 1037 (2008), pp.249-253.

[7] A. P. Mills Jr., Nucl. Instr. Meth. Phys. Res. B 192 (2002), pp.107-116.

[8] R. G. Greaves and C. M. Surko, Nucl. Instr. Meth. Phys. Res. B 192 (2002), pp.90-96.

[9] C. He, E. Hamada, N. Djourelov, T. Suzuki, H. Kobayashi, K. Kondo and Y. Ito. Nucl. Instr. Meth. Phys. Res. B 211 (2003), pp.571-576.

[10] N. Oshima, T. Suzuki, I. Kanazawa and Y. Ito, Appl. Surf. Sci. 116 (1997), pp.82-86.

[11] D. Schödlbauer, P. Sperr, G. Kögel and W. Triftshäuser, Nucl. Instr. Meth. Phys. Res. B 34 (1988), pp.258-268.