Fermilab, Batavia
We review the sources and effects of radiation damage in silicon-based particle detectors and electronics. Recent R&D has established basic mechanisms for bulk damage in silicon and several possible mitigation strategies. We will dicsuss radiation damage effects on CMOS, Silicon-On-Insulator, and bipolar technologies as well as mitigation strategies.
LANL, Los Alamos, New Mexico
Beam position monitors planned for the LANSCE diagnostics upgrade will be required to measure beam position and phase of the 201.25-MHz bunched beam in the proton linac. One method to do this is direct down conversion to in-phase and quadrature-phase data of the BPM signals using either commercial digitizers or custom designed hardware. We are evaluating selected hardware for systems with emphasis on COTS hardware to the extent practical. Basic system requirements include a beam current range of 26 db, position resolution of 0.05% of beam aperture and relative phase measurement with 0.25 degree resolution. We present our results to date on three approaches including ZTEC Instruments ZT-410 digitizers, a custom four-channel ADC analog front end board combined with National instruments, Inc. digital I/O and some limited data taken with the Instrumentation Technologies Libera system. The Libera system is a stand-alone BPM system. The other two systems use PCI cards in a standard PC running Windows XP. Our primary points of comparison include measured position resolution, phase resolution, phase linearity, minimum cycle rate and approximate cost for these portions of a BPM system.
GSI, Darmstadt
LBNL, Berkeley, California
TU Darmstadt, Darmstadt
Non-intercepting Beam Induced Fluorescence (BIF) monitors determine transversal beam profiles by observation of fluorescence light originating from excited residual gas molecules. Thus they are an alternative to conventional intercepting devices. Single photon counting is performed using an image intensified digital CCD camera. We investigated the BIF process in the energy range of 7.7 keV/u to 750 MeV/u in residual nitrogen. Experiments at low beam energies were performed at a Marx-accelerator (NDCX) at Berkeley Lab whereas mid and high energy experiments were carried out at GSI accelerators. Especially in the vicinity of targets the neutron-generated radiation level limits the monitor's signal to background ratio. Therefore the radiation background was investigated for different ion species and particle energies. Background simulations using a Monte Carlo transport code are compared to experimental data measured with scintillators, thermo luminescence detectors and the BIF monitor. Alternative image intensifier techniques are presented as well as shielding concepts. Furthermore the dynamics of ionized nitrogen molecules in the electric field of intense ion beams is discussed.
CEA, Gif-sur-Yvette
In the IFMIF-EVEDA framework, a high deuteron beam intensity (125 mA - 9 MeV) accelerator will be built and tested at Rokkasho (Japan). The development of this accelerator is shared between France, Italy and Spain. France (CEA-Saclay) and Spain (Ciemat-Madrid) are responsible of the beam instrumentation from the RFQ to the beam dump. One of the most challenging detectors is the Beam Transverse Profile Monitor (BTPM), and the Saclay group decided to investigate such a monitor based on residual gas ionisation. In order to study the feasibility, we plan in a first step to built a prototype. This monitor use a high electric field to drive the products (electrons and ions) of ionisation to resistive micro-strips. At first sight, no amplification is necessary! This prototype will be tested in the IPHI high intensity (100 mA) proton beam at Saclay to answer this question in particular, and to check the feasibility in general.