2024-03-28T21:26:25Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1956032019-11-28T02:49:36Zcom_10261_119com_10261_4col_10261_498
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Chamizo, Elena
author
López-Lora, Mercedes
author
2017-08-14
The 1 MV AMS system at the Centro Nacional de Aceleradores (CNA, Seville, Spain) was the first multielemental compact device designed and manufactured by High Voltage Engineering Europa (HVEE, Amersfoort,
Netherlands). In February 2015, the stripper gas was changed from Ar to He. Since then, our group has worked
extensively on the optimization of the new parameters of the measurement for actinides (236U, 237Np, 239,240Pu and
241,243Am). Besides, additional information on the stripping process with He gas at terminal voltages between 500
and 1000 kV has been gained. Maximum stripping yields for U3+ are achieved at about 650 kV, with a transmission
through the accelerator of 38% (47% stripping yield). This is in contrast with Ar gas, with 11% maximum
transmission for U3+ (16% stripping yield) [1]. Scattering processes with residual stripping gas along the highenergy acceleration tube, limit drastically the abundance sensitivity that can be actually achieved, on a system
where only a sector magnet is available on the high-energy side. A thorough adjustment of the slits and of the
stripper gas pressure becomes necessary to achieve competitive figures of merit for: a) 236U, being 9x1011 the
lowest 236U /238U atom ratios that can be measured; and b) 237Np, where the 238U scattering tail imposes serious
restrictions on the limit of detection. The experienced gained during these years on our system will be shared. On
the other hand, the state of the art of the CNA actinides measurement program will be briefly presented.
14th International conference on Accelerator Mass Spectrometry (2017)
http://hdl.handle.net/10261/195603
Actinides measurement with He stripping at the Centro Nacional de Aceleradores