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Indian Journal of Pure & Applied Physics (IJPAP) >
IJPAP Vol.50 [2012] >
IJPAP Vol.50(07) [July 2012] >
| Title: | Scattering of neutrons in a high energy proton accelerator enclosure and the production of 41Ar and 14C activity using FLUKA |
| Authors: | Biju, K
Sunil, C
Sarkar, P K |
| Keywords: | Proton accelerator
Argon-14
Carbon-14
FLUKA
Monte Carlo method |
| Issue Date: | Jul-2012 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | The neutron field inside high energy and high intensity proton accelerators
can produce activation of air. The neutrons backscattered by the concrete walls
contribute largely to production of argon-41 and carbon-14 concentration.
Detailed knowledge on the neutron spectrum is necessary for the accurate
estimation as the neutrons lying above thermal energy up to around 1.5 MeV, can
also produce the 41Ar considerably large amount in addition to the
thermal neutrons. Hence, the reflection of neutrons in a typical proton
accelerator facility for proton energies in the range 100-500 MeV by concrete
walls and the concentration of 41Ar and 14C has been
studied in detail in using FLUKA Monte Carlo code. The neutron spectra inside
the facility clearly indicate the dominance of the neutrons of energies within
1.5 MeV. The estimated neutron albedo/backscatter factors for the secondary
generated by the 100 MeV proton beam falling on the copper target have been
estimated around 11%. The build up of 41Ar and 14C
concentration for a 24 hr proton beam irradiation and the decay of the activity
for the next 24 hours after the beam shut down are estimated. The Monte Carlo
computed saturated 41Ar concentration values are 2.5 times higher
than that of the estimations based on analytical calculations, which assume the
activation only by thermal neutrons. |
| Page(s): | 465-468 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-1041 (Online); 0019-5596 (Print) |
| Source: | IJPAP Vol.50(07) [July 2012]
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