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Two types of noninterceptive optical monitors, based on gas fluorescence, have been designed for use on the Linear IFMIF Prototype Accelerator (LIPAc) that is currently under development (a 125 mA, 9 MeV, 175 MHz continuous wave deuteron beam). These diagnostics offer a technique to characterize the transverse beam profile for medium to high current hadron beams, without intercepting the beam core. This paper reports on beam tests using the prototype monitors developed for LIPAc. Tests were carried out at an experimental line of the Centro Nacional de Aceleradores cyclotron, using 9 MeV deuterons with beam currents from 0.4 to 40 μA. In addition, transverse beam profile measurements were performed under high background radiation (e.g. gamma dose rate up to 83 mSv/h). Preliminary cross-checks with different profilers, as well as a systematic scan of beam current and vacuum pressures and tests with different injected gases (nitrogen and xenon) have been performed. In this work, we present a brief description of the experimental setup and the first measurements obtained with these prototype profilers plus a discussion of the first analysis of the background signal in a detector as a function of radiation background.

In this work we present the output factor measurements of a clinical linear accelerator using a silicon strip detector coupled to a new system for complex radiation therapy treatment verification. The objective of these measurements is to validate the system we built for treatment verification. The measurements were performed at the Virgin Macarena University Hospital in Seville. Irradiations were carried out with a Siemens ONCOR™ linac used to deliver radiotherapy treatment for cancer patients. The linac was operating in 6 MV photon mode; the different sizes of the fields were defined with the collimation system provided within the accelerator head. The output factor was measured with the silicon strip detector in two different layouts using two phantoms. In the first, the active area of the detector was placed perpendicular to the beam axis. In the second, the innovation consisted of a cylindrical phantom where the detector was placed in an axial plane with respect to the beam. The measured data were compared with data given by a commercial treatment planning system. Results were shown to be in a very good agreement between the compared set of data.