Year-end Sale % OFF 
Abstract
The well-known foil activation technique was used to calibrate an ionisation chamber employed for the on-line beam monitoring of a 120GeVc−1 mixed proton/pion beam at CERN. Two monitoring reactions were employed: the standard 27Al(p,3pn)24Na and the alternative natCu(p,x)24Na. The parameters on which the technique critically depends and the adopted solutions are thoroughly analysed are the cross-section, the contribution of the competing reactions to the induced activity and the recoil nuclei effect. The experimental results are compared with FLUKA Monte Carlo simulations and with past results obtained with various calibration techniques. The comparison confirms that both reactions can be effectively employed. The natCu(p,x)24Na reaction shows advantages because its cross-section is known at very high energies with a low uncertainty and the production of 24Na is not affected by competing low energy neutron-induced reactions. The contribution of the competing reactions in the case of the 27Al(p,3pn)24Na reaction has been estimated to be 4.3%/100mgcm−2, whereas the effect of recoil nuclei is negligible.
Highlights
The intensity of high energy proton beams is monitored via measurements of the beam current, which can be performed via absolute measurement or indirect techniques [1,2]
The experimental results are compared with FLUKA Monte Carlo simulations and with past results obtained with various calibration techniques
The values of the calibration factor as derived via the activation of the aluminium and the copper foils are coherent within their range of uncertainties
Summary
The intensity of high energy proton beams is monitored via measurements of the beam current, which can be performed via absolute measurement or indirect techniques [1,2]. Different devices can be employed: beam current transformers [3,4], Faraday cups [1,5] or particle detectors such as scintillators [6,7], ICs [8,9] and secondary electron emission monitors [10,11]. The high energy beams are characterised by a current varying between a few fA and tens of pA These currents are too low to allow using beam current transformers and secondary electron emission monitors, whereas scintillators are used only in the lower part of the intensity range to avoid saturation, and Faraday cups cannot be used for on-line monitoring. The relative percentages depend on the beam energy [13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
