An intense proton beam diagnostic using the {sup 7}Li(p,{gamma}{sup 8})Be {yields} {sup 141}Pr({gamma},n){sup 140}Pr({beta}{sup +}) nuclear reaction sequence

Conference · Sun May 01 04:00:00 EDT 1994

OSTI ID:10149793

Evans, C B ^[1]; Cooper, G W ^[2]; Ruiz, C L; Leeper, R J ^[3]

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1. Westinghouse Hanford Co., Richland, WA (United States)
2. New Mexico Univ., Albuquerque, NM (United States)
3. Sandia National Labs., Albuquerque, NM (United States)

An indirect nuclear activation diagnostic was developed to measure the proton fluence onto a thick target of lithium metal located in the diode region of pulsed power accelerators. This diagnostic uses the nuclear sequence {sup 7}Li(p,{gamma}){sup 8}Be=>{sup 14l}Pr({gamma},n){sup 140}Pr({beta}{sup +}) to relate the proton reaction fluence to induced {sup 140}Pr activity. This diagnostic was calibrated using a Van de Graaff accelerator. Energetic protons were focused onto a thick lithium target driving the {sup 7}Li(p,{gamma}){sup 8}Be reaction. The resulting prompt gamma rays activated a secondary {sup l4l}Pr target via the reaction {sup 141}Pr({gamma},n){sup 140}Pr({beta}{sup +}). A NaI gamma-gamma coincidence detector system was used to measure the induced {sup 140}Pr activity as a function of proton energy and proton fluence. These data yielded a calibration curve for proton energies ranging from 2 to 12 MeV. Since deuterium impurities can interfere with this diagnostic by driving the reaction sequence {sup 7}Li(d,n){sup 8}Be=> {sup 141}Pr(n,2n){sup 140}Pr, a similar calibration experiment was conducted using deuterium ions. These data yielded a correction factor that can be used to determine the deuterium contribution to the {sup 140}Pr activity providing that the deuterium beam fraction is known.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 10149793
• Report Number(s): SAND--94-0329C; CONF-940552--3; ON: DE94011437; BR: GB0103012
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
430303
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700411
DIAGNOSTIC TECHNIQUES
EXPERIMENTAL FACILITIES AND EQUIPMENT
INERTIAL CONFINEMENT
INERTIAL CONFINEMENT DEVICES
ION BEAMS
LITHIUM 7 TARGET
PARTICLE BEAM FUSION ACCELERATOR
PHOTONUCLEAR REACTIONS
PRASEODYMIUM 141 TARGET
PROTON REACTIONS