Transport mechanism of MeV protons in tapered glass capillaries

Journal Article · Mon Aug 15 04:00:00 EDT 2011 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3624617· OSTI ID:22036706

Hasegawa, Jun; Oguri, Yoshiyuki ^[1]; Jaiyen, Sarawut; Polee, Chalermpong; Chankow, Nares ^[2]

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1. Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550 (Japan)
2. Department of Nuclear Technology, Faculty of Engineering, Chulalongkorn University, Bangkok 10330 (Thailand)

To investigate the transport mechanism of MeV protons in tapered glass capillaries, spatially resolved energy spectra were measured for proton microbeams focused by 20-{mu}m-outlet capillaries having various taper angles. Three-dimensional Monte Carlo (MC) simulations were also performed to support the experiments and trace each particle in the capillary in more detail. The dependence of the proton energy distribution on the outgoing angle proved that the capillary-focused proton beam consists of two different components, protons traveling straight through the capillary without colliding with the capillary wall and protons scattered by the capillary inner wall. Moreover, the focusing effect of the tapered glass capillary was found to be mainly due to the scattered beam component. The MC simulations well reproduced the experimental results and showed that beam focusing ratios of 1.6-2.4 are possible with capillaries having a convex inner wall. The flight distance of the scattered proton in the capillary glass body was found to play an important role in determining transport efficiency of the protons through the capillary.

• OSTI ID: 22036706
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 4 Vol. 110; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BEAM PROFILES
BEAM TRANSPORT
CAPILLARIES
CHARGED-PARTICLE TRANSPORT
COMPUTERIZED SIMULATION
DISTANCE
EFFICIENCY
ENERGY SPECTRA
FOCUSING
GLASS
MEV RANGE
MONTE CARLO METHOD
PROTON BEAMS
PROTONS
THREE-DIMENSIONAL CALCULATIONS