In-air ion beam analysis with high spatial resolution proton microbeam

Abstract

One of the possible ways to maintain the micrometer spatial resolution while performing ion beam analysis in the air is to increase the energy of ions. In order to explore capabilities and limitations of this approach, we have tested a range of proton beam energies (2 -6 MeV) using in-air STIM (Scanning Ion Transmission Microscopy) setup. Measurements of the spatial resolution dependence on proton energy have been compared with SRIM simulation and modelling of proton multiple scattering by different approaches. Results were used to select experimental conditions in which 1 micrometer spatial resolution could be obtained.High resolution in-air microbeam could be applied for IBIC (Ion Beam Induced Charge) tests of large detectors used in nuclear and high energy physics that otherwise can not be tested in relatively small microbeam vacuum chambers.

Development of the Dual-Beam Ion Irradiation Facility for Fusion Materials (DiFU)

“…Effects of ion beam spread, caused by ion Multiple Scattering (MS) in degrader foils, have to be taken into account when ion beam energy degraders are used [ 30 ]. The angular spreads of heavy ions in Al foils could be modeled using Sigmund and Winterborn [ 31 ] model of MS angular distributions and their approximation by Pseudo-Voigt distributions [ 32 , 33 ]. The angular spread of protons and He ions due to MS in aluminum foils could be simulated as well.…”

Monolithic HV-CMOS sensors for a beam monitoring system of therapeutic ion beams

“…This loss is caused by a baseline drop of the first stage amplifier when the sensor is hit by an ion beam at high intensity. The in-air proton microbeam at Ruđer Bošković Institute [6] was used in order to determine the region with a typical size of O (μm 2 ) and the corresponding signal processing structure which is responsible for the baseline drop of the in-pixel amplifier when hit by ions.…”