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A novel real-time optical fibered dosimetry system based on optically stimulated luminescence (OSL) of SrS:Ce,Sm phosphor was developed and is presented. The advantages of this system are the combination of OSL and optical fibers, immediate readout, simplicity of use, low cost, reliability, flexibility, and robustness. Experimental results show an excellent linearity with the dose (0.01 to 6 Gy), repeatability better than 2%, radiation sensitivity up to 80 mV x c[Gy.sup.-1] and accuracy since error on dose is less than 5%. The applications targeted are the measurement of the dose delivered during a treatment in radiation therapy and the monitoring of the dose or dose-rate around or in nuclear reactor and accelerator facilities in high energy physics. Further experiments are still to be conducted in order to fully characterize the system and evaluate the feasibility of each application mentioned. Index Terms--Optical fiber, optically stimulated luminescence, OSL, radiation dosimetry, real-time dosimetry.

RadFET and p-i-n diode semiconductor dosimeters from different manufacturers will be used for radiation monitoring at the Experiments of the CERN LHC accelerator. In this work these sensors were exposed over three months in the CERN-IRRAD6 facility that provides mixed high-energy particles at low rates. The aim was to validate the operation of such sensors in a radiation field where the conditions are close to the ones expected inside full working LHC particle detectors. The results of this long-term irradiation campaign are presented, discussed and compared with measurements by other dosimetric means as well as Monte Carlo simulations. Finally, the integration of several dosimetric devices in one sensor carrier is also presented. Index Terms--Accelerators, dosimetry, MOSFET, particle beams, p-i-n diodes, proton, RadFET, radiation damage.

A version of the Optically Stimulated Luminescence (OSL) sensor specifically developed to monitor the dose online in radiation facilities is presented and calibrated with [sup.60]Co. The lowest dose measurable at the extremity of a 20 m cable is 0.3 mGy. Index Terms--Online dosimetry, Optically Stimulated Luminescence (OSL), protons.

For the first time, Optically Stimulated Luminescent (OSL) materials with enhanced neutron-sensitivity have been irradiated. The neutron irradiations were carried out in the accelerator-like environment of the IRRAD2 facility at CERN, Geneva, Switzerland and in the TRIGA reactor at JSI, Ljubljana, Slovenia. The results show the possibility to measure with good accuracy the thermal and the fast components of these two different neutron spectra by means of OSL materials doped with Boron or mixed with Polyethylene. The applicability of this technology in the measurement of the neutron components in the complex radiation environment expected at CERN LHC experiments is therefore demonstrated. Index Terms--Neutron dosimetry, optically stimulated luminescent (OSL) dosimetry, particle beams.

We present irradiation experiments carried out on RadFETs in the high-intensity T2 neutron beam at the CRC-UCL in Belgium. The aim of the test was to characterize the neutron response of RadFETs in view of their use as an integrated part of a radiation-monitoring sensor for the CERN Large Hadron Collider (LHC) experiments. Two types of RadFETs were investigated up to a total neutron fluence of 3 x [10.sup.14] [cm.sup.-2] corresponding to a deposited dose of 744 Gy in silicon. The responses of bare devices to neutrons are compared to the commonly used reference measurements with gamma rays. It is found that the gamma ray calibration cannot directly be adopted to convert the RadFET signals into neutron dose. In a second experiment, the influence of a plastic packaging, simulated by polyethylene slabs of different thicknesses, was tested in the neutron beam and compared to GEANT4 Monte Carlo simulations. An increase of the RadFET neutron sensitivity by a factor of up to 7 due to the packaging is found. The infuence of these findings on the conception of the radiation-monitoring sensor is discussed. Index Terms--Dosimetry, gamma-ray detectors, neutron beams, RadFETs, radiation monitoring.

The concept of an active integrated dosimetric sensor for the radiation monitoring of the Compact Muon Solenoid experiment at the CERN (European Center for Nuclear Research) Large Hadron Collider is presented. The sensor, based on RadFET, OSL, p-i-n diode, and pad detector dosimeters, will measure both ionizing and nonionizing energy losses in the harsh radiation environment produced by hadron interactions. Index Terms--Optically stimulated luminescence, p-i-n diode, particle beams, RadFET, real-time dosimetry.

For the first time, optically stimulated luminescent (OSL) dosimeters have been irradiated at CERN with high-energy particles. Two experiments with existing OSL films are presented: measuring the dose delivered by 3.66-GeV negative pions and mapping the intensity profile of a 23-GeV proton beam. An on-line dosimeter is also presented and applied to the monitoring of the dose delivered by a 500-MeV electron beam. The results are discussed with regards to the specific concerns raised by high doses and high energies. Index Terms--Dose map, high-energy protons, optically stimulated luminescent (OSL) dosimetry.

Future high energy physics experiments at CERN's Large Hadron Collider will use high precision silicon detectors for tracking purposes. The hadronic component of the radiation received threatens the lifetime of these detectors and it is vital to choose the silicon starting material to maximise the performance and lifetime. Ion-implanted silicon detectors with various initial resistivities and germanium concentrations have been irradiated with high energy protons up to a fluence of [10.sup.14] [cm.sup.-2]. The change in leakage current and full depletion voltage have been studied both as a function of fluence and of time after irradiation. Measurements were made up to 100 days post-irradiation at room temperature and then using heating techniques to accelerate processes up to the equivalent of over 10 years at room temperature. The leakage-current damage constant is shown to be independent of the starting material while the conduction type inversion point and the long-term annealing of the depletion voltage are sensitive to the initial resistivity and impurity concentrations.

Radiation hardened SOI-CMOS is a possible candidate technology for mixed analog-digital signal processing electronics in experiments at the future high luminosity hadron colliders. In view of this application, we have studied the analog parameters of transistors realized in the Thomson TMS HSOI3-HD technology before and after exposure to total doses similar to those expected in the CERN Large Hadron Collider LHC. The devices have been irradiated up to 10 Mrad with 60Co and 3 center dot 10 to the fourteenth power neutrons/cm squared. The changes in the threshold voltage V(sub th) of front and back gates, leakage current and transconductance are studied. Subthreshold slope and charge pumping techniques have been used to estimate the interface state formation. Noise measurements in the 0.1kHz-3MHz bandwidth have been performed. The noise is comparable to that of a bulk CMOS process. Post irradiation effects have been regularly monitored and threshold voltage rebound for n-channel transistors is observed.

A readout chip implemented in an array with 16 columns at 500 micrometers pitch and 63 rows at 75 micrometer pitch was studied. The chip was bonded with solder bumps to a silicon detector with matching pixel elements. A trigger signal strobes event information in a pixel which allows it to be read out. This process cannot be done in the absence of a strobe. The hybrid detector has been tested and found to be sufficiently effective.

Silicon pad detectors with initial resistivities between 2.6 and 12.9 kilo ohms centimeter were irradiated with neutrons equivalent to 1 MeV energy up to a fluence of 5 times 10 (super 13)n cm (super -2). Results show an increase of the reverse current of unbiased n-type silicon diodes followed by a 30 to 40% room temperature annealing after a few months. A similar increase in current occurs in p-type diodes but conduction type is conserved.

The subject of radiation damage to silicon detectors induced by 24-GeV/c protons and nuclear reactor neutrons has been studied. Detectors fabricated on single-crystal silicon enriched with various impurities have been tested. Significant differences in electrically active defects have been found between the various types of material. The results of the study suggest for the first time that the widely used nonionizing energy loss (NIEL) factors are insufficient for normalization of the electrically active damage in case of oxygen- and carbon-enriched silicon detectors. It has been found that a deliberate introduction of impurities into the semiconductor can affect the radiation hardness of silicon detectors. Index Terms--Neutrons, protons, radiation damage, radiation hardness, silicon detectors.