Ion detector for Accelerator Mass Spectrometry based on low-pressure TPC with THGEM readout

TL;DR

This paper introduces a novel ion detection method for Accelerator Mass Spectrometry using a low-pressure TPC with THGEM readout, enabling precise ion track measurement and effective isobaric separation.

Contribution

It presents a new technique combining low-pressure TPC and THGEM for improved ion identification and separation in AMS, demonstrated with alpha particle tracks and simulations.

Findings

Achieved 2% resolution in ion track range measurement.

Successfully separated boron and beryllium ions at ten sigma level.

Potential application in geological dating and Cenozoic era geochronology.

Abstract

A new technique for ion identification in Accelerator Mass Spectrometry (AMS) has been proposed by measuring the ion track ranges using a low-pressure TPC. As a proof of principle, a low-pressure TPC with charge readout using a THGEM multiplier was developed. The tracks of alpha particles from various radioactive sources were successfully recorded in the TPC. The track ranges were measured with a high accuracy, reaching the 2% resolution level. Using these results and the SRIM code simulation, it is shown that the isobaric boron and beryllium ions can be effectively separated at ten sigma level. It is expected that this technique will be applied in the AMS facility in Novosibirsk for dating geological objects, in particular for the geochronology of Cenozoic Era.