Engineering Commons^™

Intraoperative Solid-State Based Urethral Dosimetry In Low Dose Rate Prostate Brachytherapy, Dean Cutajar, G. Takacs, M. Lerch, T. Braddock, J. Bucci, J. Brady, L. Duggan, K. Enari, M. Zaider, M. Zelefsky, Anatoly Rosenfeld

Michael L.F. Lerch

This paper presents in phantom testing of a recently developed intraoperative minidosimetry system, designed to measure the dose along the urethra during low dose rate prostate brachytherapy. This system is based on a silicon minidetector and uses spectroscopy to calculate the localized dose from the treatment radiation. The minidosimetry system was demonstrated to be operational at body temperature, with a near isotropic response to radiation at all angles. Phantom measurements have shown the minidosimetry system to measure the dose from multiple seeds to within 5% of planning system calculated doses. This system is an ideal complement to ultrasound guided seed …

The Feasibility Study And Characterziation Of A Two-Dimensional Diode Array In “Magic Phantom” For High Dose Rate Brachytherapy Quality Assurance, A Espinoza, B Beeksma, M Petasecca, I Fuduli, C Porumb, D L. Cutajar, S Corde, M A. Jackson, M Lf Lerch, Anatoly B. Rosenfeld

Michael L.F. Lerch

High dose rate (HDR) brachytherapy is a radiation treatment technique capable of delivering large dose rates to the tumor. Radiation is delivered using remote afterloaders to drive highly active sources (commonly 192Ir with an air KERMA strength range between 20 000 and 40 000 U, where 1 U = 1 uGy m2/h in air) through applicators directly into the patient's prescribed region of treatment. Due to the obvious ramifications of incorrect treatment while using such an active source, it is essential that there are methods for quality assurance (QA) that can directly and accurately verify the treatment plan and the …

Neutron Dosimetry With Planar Silicon P-I-N Diodes, Anatoly B. Rosenfeld, M. Yudelev, M. L. Lerch, I. Cornelius, P. Griffin, V. L. Perevertailo, I. E. Anokhin, O. S. Zinets, V. I. Khivrich, M. Pinkovskaya, D. Alexiev, M. Reinhard

Michael L.F. Lerch

New nonionizing energy losses (NIEL) sensors based on silicon planar p-i-n diodes of different geometry have been investigated and their response to fast neutron field compared with bulk diodes. The possibility of obtaining a wide range of sensitivities in these NIEL sensors simultaneously with measurements of IEL has been demonstrated.

Mosfet Dosimetry With High Spatial Resolution In Intense Synchrotron-Generated Xray Microbeams, Erik Siegbahn, E Brauer-Krisch, A Bravin, Heidi Nettelbeck, Michael Lerch, Anatoly Rosenfeld

Michael L.F. Lerch

Various dosimeters have been tested for assessing absorbed doseswith microscopic spatial resolution in targets irradiated by high-flux, synchrotron-generated,low-energy (~30–300 keV) x-ray microbeams. A MOSFET detector has been usedfor this study since its radio sensitive element, which isextraordinarily narrow (~1 µm), suits the main applications of interest, microbeamradiation biology and microbeam radiation therapy (MRT). In MRT, micrometer-wide,centimeter-high, and vertically oriented swaths of tissue are irradiated byarrays of rectangular x-ray microbeams produced by a multislit collimator(MSC). We used MOSFETs to measure the dose distribution, producedby arrays of x-ray microbeams shaped by two different MSCs,in a tissue-equivalent phantom. Doses were measured near …

Experimental Investigation Of The 100 Kev X-Ray Dose Response Of The High-Temperature Thermoluminescence In Lif: Mg, Ti (Tld-100): Theoretical Interpretation Using The Unified Interaction Model, Jayde Livingstone, Y Horowitz, L Oster, H Datz, Michael Lerch, Anatoly Rosenfeld, A Horowitz

Michael L.F. Lerch

The dose response of LiF:Mg,Ti (TLD-100) chips was measured from 1 to 50 000 Gy using 100 keV X rays at the European Synchroton Radiation Facility. Glow curves were deconvoluted into component glow peaks using a computerised glow curve deconvolution (CGCD) code based on first-order kinetics. The normalised dose response, f(D), of glow peaks 4 and 5 and 5b (the major components of composite peak 5), as well as peaks 7 and 8 (two of the major components of the high-temperature thermoluminescence (HTTL) at high levels of dose) was separately determined and theoretically interpreted using the unified interaction model (UNIM). …

In Vivo Real-Time Rectal Wall Dosimetry For Prostate Radiotherapy, Nicholas Hardcastle, Dean L. Cutajar, Peter E. Metcalfe, Michael L F Lerch, Vladimir L. Perevertaylo, Wolfgang A. Tome, Anatoly B. Rosenfeld

Michael L.F. Lerch

Rectal balloons are used in external beam prostate radiotherapy to provide reproducible anatomy and rectal dose reductions. This is an investigation into the combination of a MOSFET radiation detector with a rectal balloon for realtime in vivo rectal wall dosimetry. The MOSFET used in the study is a radiation detector that provides a water equivalent depth of measurement of 70 μm. Two MOSFETs were combined in a face-to-face orientation. The reproducibility, sensitivity and angular dependence were measured for the dual MOSFET in a 6 MV photon beam. The dual MOSFET was combined with a rectal balloon and irradiated with hypothetical …

A Silicon Strip Detector Dose Magnifying Glass For Imrt Dosimetry, J.H.D Wong, Martin Carolan, Michael Lerch, Marco Petasecca, Sutinder Khanna, V Perevertaylo, Peter Metcalfe, Anatoly Rosenfeld

Michael L.F. Lerch

Purpose: Intensity modulated radiation therapy (IMRT) allows the delivery of escalated radiation dose to tumor while sparing adjacent critical organs. In doing so, IMRT plans tend to incorporate steep dose gradients at interfaces between the target and the organs at risk. Current quality assurance (QA) verification tools such as 2D diode arrays, are limited by their spatial resolution and conventional films are nonreal time. In this article, the authors describe a novel silicon strip detector (CMRP DMG) of high spatial resolution (200 μm) suitable for measuring the high dose gradients in an IMRT delivery. Methods: A full characterization of the …

Comparison Of The New Moskin Detector And Fiber Optic Dosimetry System For Radiotherapy, Ian Kwan, Bong Soo Lee, Wook Jae Yoo, Donghyun Cho, Kyoungwon Jang, Sanghun Shin, Martin Carolan, Michael Lerch, V Perevertaylo, Anatoly Rosenfeld

Michael L.F. Lerch

In radiotherapy, interest in real-time dosimetry stems from the desire to monitor the dose delivered to the target volume and the surrounding normal tissue to enable clinicians to track the progress of the treatment, and prevent surrounding tissue from receiving too much radiation dose. In this study, the dosimetric performance of the new MOSkin dosimeter and a Bicron BCF-20 scintillating fiber was compared to depth dose measurements taken with a Farmer-type ionization chamber. The performance of the MOSkin and BCF-20 detectors in the build-up region of the depth dose curve, where the dose gradient is steep, is also compared to …

Potential High Resolution Dosimeters For Mrt, E. Brauer-Krisch, Anatoly B. Rosenfeld, Michael L. Lerch, Marco Petasecca, M. Akselrod, J. Sykora, J. Bartz, M. Ptaszkiewicz, P. Olko, A. Berg, M. Wieland, S. Doran, T. Brochard, A. Kamlowski, G. Cellere, A. Paccagnella, Erik A. Siegbahn, Y. Prezado, I. Martinez-Rovira, A. Bravin, Laurent Dusseau, P. Berkvens

Michael L.F. Lerch

Microbeam Radiation Therapy (MRT) uses highly collimated, quasi-parallel arrays of X-ray microbeams of 50-600 keV, produced by 2nd and 3rd generation synchrotron sources, such as the National Synchrotron Light Source (NSLS) in the U.S., and the European Synchrotron Radiation Facility (ESRF) in France, respectively. High dose rates are necessary to deliver therapeutic doses in microscopic volumes, to avoid spreading of the microbeams by cardiosynchronous movement of the tissues. A small beam divergence and a filtered white beam spectrum in the energy range between 30 and 250 keV results in the advantage of steep dose gradients with a sharper penumbra than …

Studies Of The Characteristics Of A Silicon Neutron Sensor, Igor E. Anokhin, Oleg S. Zinets, Anatoly B. Rosenfeld, Michael L. Lerch, M. Yudelev, V. L. Perevertaylo, Mark I. Reinhard, Marco Petasecca

Michael L.F. Lerch

Electrical characteristics and neutron dosimetry properties of silicon based p-i-n diodes are presented in support of the applications in the sensors for beam monitoring and medical physics. Both the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of silicon planar p-i-n diode sensors with cylindrical geometry have been theoretically modeled and experimentally measured. The shifts of the forward and reverse diode characteristics of the sensors versus the neutron dose have been obtained. It is shown that the neutron irradiation caused shift of the forward voltage of the p-i-n diodes is proportional to the current at which it is measured in the case …

Evaluation Of A Thin Microstrip Detector For High Spatial Resolution Dosimetry, J Kalliopuska, Ashley Cullen, Michael Lerch, Marco Petasecca, M Santala, Anatoly Rosenfeld

Michael L.F. Lerch

VTT and Aalto University have supplied thin microstrip detector prototypes to CMRP for evaluation for the high spatial resolution dosimetry. The evaluation for dosimetry in microbeam radiation therapy (MRT) was done in a synchrotron microbeam at ESRF, France. Measurements studied a response of a single strip on the synchrotron microbeam in face-on and edge-on modes using CMRP designed and developed readout electronics for a parallel readout of single strips. Measurements were done in a passive mode without bias voltage and the detector was scanned through an array of intensive planar microbeams with the nominal width of 50 μm. The face-on …

In Vivo Dosimetry And Seed Localization In Prostate Brachytherapy With Permanent Implants, Anatoly B. Rosenfeld, Dean Cutajar, M. L. Lerch, G. J. Takacs, T. Braddock, V. L. Perevertailo, J. Bucci, J. Kearsley, M. Zaider, M. Zelefsky

Michael L.F. Lerch

This paper reports on the development of an interactive, intraoperative dose planning system for seed implant brachytherapy in cancer treatment. This system involves in vivo dosimetry and the ability to determine implanted seed positions. The first stage of this project is the development of a urethral alarm probe to measure the dose along the urethra during a prostate brachytherapy treatment procedure. Ultimately, the system will be used to advise the physicians upon reaching a preset dose rate or dose after total seed decay in the urethra during the seed placement. The second stage is the development of a method and …

From Hep To Medical Radiation Dosimetry - The Silicon Strip Detector Dose Magnifying Glass, J.H.D Wong, Dean Cutajar, Michael Lerch, Marco Petasecca, T Knittel, Martin Carolan, V Perevertaylo, Peter Metcalfe, Anatoly Rosenfeld

Michael L.F. Lerch

High energy physics (HEP) experiments and research gave rise to the development of high spatial resolution tracking vertex detectors and the accompanying data acquisition systems (DAQ) capable of high temporal resolution measurements. The technology translation from HEP to the day to day medical radiation dosimetry is gradual but certain. This paper discusses the design and development of a high spatial resolution (0.2 mm pitch) silicon strip detector referred to as the Dose Magnifying Glass designed and prototyped by the Centre for Medical Radiation Physics (CMRP), University of Wollongong. The DMG has 128 phosphor implanted n+ strips on a p-type silicon …

Characterisation Of Delta E-E Particle Telescope Using The Ansto Heavy Ion Microprobe, Andrew Wroe, Dale Prokopovich, Michael Lerch, Anatoly Rosenfeld, David Cohen, Mihail Ionescu, Iwan Cornelius, Rainer Siegele, A Fazzi, S Agosteo, A Pola, Mark Reinhard

Michael L.F. Lerch

No abstract provided.

Edge-On Face-To-Face Mosfet For Synchrotron Microbeam Dosimetry: Mc Modeling, Anatoly B. Rosenfeld, E. A. Siegbahn, E. Brauer-Krisch, A. Holmes-Siedle, M. L. Lerch, A. Bravin, I. Cornelius, G. J. Takacs, N. Painuly, H. Nettleback, T. Kron

Michael L.F. Lerch

The dosimetry of X-ray microbeams using MOSFETs results in an asymmetrical beam profile due to a lack of lateral charged particle equilibrium. Monte Carlo simulations were carried out using PENELOPE and GEANT4 codes to study this effect and a MOSFET on a micropositioner was scanned in the microbeam. Based on the simulations a new method of microbeam dosimetry is proposed. The proposed edge-on face-to-face (EOFF) MOSFET detector, a die arrangement proposed here for the first time, should alleviate the asymmetry. Further improvement is possible by thinning the silicon body of the MOSFET.

Urethral Spectroscopic Alarm (Usa) Probe For Prostate Implants, Anatoly Rosenfeld, Dean Cutajar, Michael Lerch, George Takacs, J Bucci, L Duggan, M Zaider, M Zelefsky, Gil'ad Cohen

Michael L.F. Lerch

Urethral Spectroscopic Alarm (USA) Probe for Prostate Implants 1A.B. Rosenfeld, 1D.L. Cutajar, 1M.L.F. Lerch, 1G.J. Takacs, 2J.A. Bucci, 2L.J. Duggan, 3M. Zaider, 4M. Zelefsky and 3G.N. Cohen 1Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia, 2Institute for Prostate Cancer, St. George Cancer Care Centre, Kogarah, Australia, 3Department of Medical Physics and 4Department of Radiation Oncology, MSKCC, New York, NY Purpose: Prostate implants are associated with excellent biochemical outcome; however, their benefit in terms of overall survival remains unknown. For many patients with early, localized prostate cancer the decision to undergo a treatment of questionable benefit yet because of …

Real-Time In Vivo Dosimetry With Mosfet Detectors In Serial Tomotherapy For Head And Neck Cancer Patients, Zhen-Yu Qi, Xiao-Wu Deng, Shao-Min Huang, Almon Shiu, Michael Lerch, Peter Metcalfe, Anatoly Rosenfeld, Tomas Kron

Michael L.F. Lerch

Purpose

A real-time dose verification method using a recently designed metal oxide semiconductor field effect transistor (MOSFET) dosimetry system was evaluated for quality assurance (QA) of intensity-modulated radiation therapy (IMRT).

Methods and Materials

Following the investigation of key parameters that might affect the accuracy of MOSFET measurements (i.e., source surface distance [SSD], field size, beam incident angles and radiation energy spectrum), the feasibility of this detector in IMRT dose verification was demonstrated by comparison with ion chamber measurements taken in an IMRT QA phantom. Real-time in vivo measurements were also performed with the MOSFET system during serial tomotherapy …

Modelling The Readout Performance Of A New Silicon Photodetector For Use In Pet, Michael Lerch, Philip Simmonds, Robert Ward, Tony Young, George Takacs, Anatoly Rosenfeld, V L Perevertaylo, Steven Meikle

Michael L.F. Lerch

No abstract provided.

Feasibility Study Of Online High-Spatial-Resolution Mosfet Dosimetry In Static And Pulsed X-Ray Radiation Fields, Anatoly B. Rosenfeld, M. L. Lerch, T. Kron, E. Brauer-Krisch, A. Bravin, A. Holmes-Siedle, B. J. Allen

Michael L.F. Lerch

Improvements have been made in the measurement of dose profiles in several types of X-ray beams. These include 120-kVp X-ray beams from an orthovoltage X-ray machine, 6-MV Bremsstrahlung from a medical LINAC in conformal mode and the 50-200 keV energy spectrum of microbeams produced at the medical beamline station of the European Synchrotron Radiation Facility. Using a quadruple metal-oxide-semiconductor field-effect transistor (MOSFET) sensor chip in "edge on" mode together with a newly developed sensor readout system, the feasibility of online scanning of the profiles of quasi-static and pulsed radiation beams was demonstrated. Measurements of synchrotron pulsed microbeams showed that a …

Evaluation Of Pixellated, Back-Sided Planar Photodetectors For High-Resolution Imaging Instrumentation, Mark Safavi-Naeini, Michael Lerch, Marco Petasecca, Giorgio Pignatel, Mark Reinhard, Anatoly Rosenfeld

Michael L.F. Lerch

Future generations of solid-state high-energy gamma imaging cameras require pixellated semiconductor photodetectors with the greatest possible detection efficiency. In this paper, a new type of planar silicon PIN photodiode is presented, in which both p+ and n+ electrodes are located on the same side of the device. The design offers highly efficient optical coupling between the backside and scintillator, providing a fill factor of close to 100%. The performance of this detector is modelled using the ISE-TCAD simulator and its electrical and spectroscopic characteristics are experimentally investigated for the case of direct interaction of ionising radiation and also with an …

Mosfet Dosimetry With High Spatial Resolution In Intense Synchrotron-Generated X-Ray Microbeams, Erik Siegbahn, E. Brauer-Krisch, Alberto Bravin, Heidi Nettelbeck, Michael Lerch, Anatoly Rosenfeld

Michael L.F. Lerch

Various dosimeters have been tested for assessing absorbed doses with microscopic spatial resolution in targets irradiated by high-flux, synchrotron-generated, low-energy (∼30–300 keV) x-ray microbeams. A MOSFET detector has been used for this study since its radio sensitive element, which is extraordinarily narrow (∼1 μm), suits the main applications of interest, microbeam radiation biology and microbeam radiation therapy (MRT). In MRT, micrometer-wide, centimeter-high, and vertically oriented swaths of tissue are irradiated by arrays of rectangular x-ray microbeams produced by a multislit collimator (MSC). We used MOSFETs to measure the dose distribution, produced by arrays of x-ray microbeams shaped by two different …

Spectral Characterization Of A Blue-Enhanced Silicon Photodetector, M. L. Lerch, Anatoly B. Rosenfeld, Philip E. Simmonds, G. N. Taylor, S. R. Meikle, V. L. Perevertailo

Michael L.F. Lerch

In this paper, we report on spectral response data and gamma ray spectroscopy measurements using two newly developed silicon photodetectors that are designed to have enhanced sensitivity in the blue spectral region. The enhanced sensitivity is a result of our newly developed ion implantation profile used to create the active area of the photodetector. The quantum efficiency of the new photodetectors (without any optimized antireflective coating) has been measured to be ~40% at a wavelength of 420 nm. Gamma ray spectroscopy experiments have been performed using a thallium doped cesium iodide, [CsI(Tl)], and a cerium doped lutetium oxy-orthosilicate, (LSO) crystal …

Design And Simulation Of Continuous Scintillator With Pixellated Photodetector, G. J. Takacs, Anatoly B. Rosenfeld, M. L. Lerch

Michael L.F. Lerch

Presents results of simulations performed as part of the development of a gamma-ray detector module comprising a nonpixellated scintillator and pixellated photodiode detector. The simulations have been carried out to determine the effect of surface treatment and dimensions of the scintillator on the ability to determine the two-dimensional position of interaction. A set of 32 different combinations of surface treatments have been considered for each crystal size. Scintillator dimensions considered have been 25×25×(3-6 mm3). For scintillator thicknesses at the low end of this range, an average accuracy of 0.5-0.6 mm is achievable for many different surface treatments. At the higher …

Performance Evaluation Of A Multipinhole Small Animal Spect System, S. R. Meikle, P. Kench, R. Wojcik, M. F. Smith, A. G. Weisenberger, S. Majewski, M. L. Lerch, Anatoly B. Rosenfeld

Michael L.F. Lerch

We have designed and constructed a small animal SPECT system based on compact, high resolution detectors and multipinhole apertures. The scanner is currently configured with two detectors mounted on a rotating gantry. Each detector comprises a NaI(Tl) crystal array (1/spl times/1/spl times/5 mm elements), a 12 cm diameter position-sensitive photomultiplier tube (Hamamatsu R3292) and a tungsten aperture with 1 or more pinholes. In this study, we performed phantom experiments to characterise the planar and tomographic performance of the scanner. Intrinsic resolution measured with a highly collimated /sup 99m/Tc point source stepped across the detector face was 1.0 /spl plusmn/ 0;.1 …

Magneto-Radiotherapy: Effect Of Magnetic Field On Dose Distribution And Rbe, Heidi Nettelbeck, Anatoly Rosenfeld, George Takacs, Michael Lerch

Michael L.F. Lerch

Magneto-radiotherapy is the application of magnetic fields during radiotherapy procedures. It aims to improve the quality of cancer treatment by altering the dose deposition of charged particles in the tissue volume being targeted. Our research has focused on applying the concept of magneto-radiotherapy to conventional linac treatment and MRT (Microbeam Radiation Therapy) oncology modalities.

Solid State Diode - Ionization Chamber Method For Measuring Out-Of-Field Neutron Dose In Proton Therapy, Amy Ziebell, B Clasie, Andrew Wroe, Reinhard Schulte, Mark Reinhard, Stephen Dowdell, Michael Lerch, Marco Petasecca, V Perevertaylo, Oleg Zinets, Igor Anokhin, Anatoly Rosenfeld

Michael L.F. Lerch

In proton therapy neutrons are introduced to out-of-field regions inside the patient. Clinicians would like to know the absorbed dose being deposited by neutrons separately to that from protons, so as to be able to directly apply their own dose equivalent weighting factors based on their opinion of the biological risk posed by neutrons in this region. The purpose of this study is to investigate a novel approach to experimentally separating the proton and neutron contributions to the absorbed dose in out-of-field regions. The method pairs specially designed silicon PIN diodes with a standard clinical ionization chamber. The sensitivity of …

The Effect Of Rectal Heterogeneity On Wall Dose In High Dose Rate Brachytherapy, Ian Kwan, Dean Wilkinson, Dean Cutajar, Michael Lerch, Anatoly Rosenfeld, Andrew Howie, Joseph Bucci, Y. Chin, V. Perevertaylo

Michael L.F. Lerch

When treating prostate cancer using high dose rate (HDR) brachytherapy, overdosing the rectal wall may lead to post-treatment rectal complications. An area of concern is related to how the rectal wall dose is calculated by treatment planning systems (TPSs). TPSs are used to calculate the dose delivered to the rectal wall, but they assume that the rectum is a water-equivalent homogeneous medium of infinite size and do not consider the effect that an air-filled “empty” rectal cavity would have on the dose absorbed along the rectal wall. The aim of this research is to quantify the effect that an air …

Mosfet Dosimetry For Microbeam Radiation Therapy At The European Synchrotron Radiation Facility, E. Brauer-Krisch, A. Bravin, M. L. Lerch, Anatoly B. Rosenfeld, J. Stepanek, M. Di Michiel, J. A. Laissue

Michael L.F. Lerch

Preclinical experiments are carried out with ~20–30 μm wide, ~10 mm high parallel microbeams of hard, broad-‘‘white’’-spectrum x rays (~50–600 keV) to investigate microbeam radiation therapy (MRT) of brain tumors in infants for whom other kinds of radiotherapy are inadequate and/or unsafe. Novel physical microdosimetry (implemented with MOSFET chips in the ‘‘edge-on’’ mode) and Monte Carlo computer-simulated dosimetry are described here for selected points in the peak and valley regions of a microbeam-irradiated tissue-equivalent phantom. Such microbeam irradiation causes minimal damage to normal tissues, possible because of rapid repair of their microscopic lesions. Radiation damage from an array of parallel …

A Real-Time In Vivo Dosimetric Verification Method For High-Dose Rate Intracavitary Brachytherapy Of Nasopharyngeal Carcinoma, Zhen-Yu Qi, Xiao-Wu Deng, X Cao, Shao-Min Huang, Michael Lerch, Anatoly Rosenfeld

Michael L.F. Lerch

Purpose: A real-time in vivo dosimetric verification method using metal-oxide-semiconductor field effect transistor (MOSFET) dosimeters has been developed for patient dosimetry in high-dose rate (HDR) intracavitary brachytherapy of nasopharyngeal carcinoma (NPC). Methods: The necessary calibration and correction factors for MOSFET measurements in 192Iridium source were determined in a water phantom. With the detector placed inside a custom-made nasopharyngeal applicator, the actual dose delivered to the tumor was measured in vivo and compared to the calculated values using a commercial brachytherapy planning system. Results: Five MOSFETs were independently calibrated with the HDR source, yielding calibration factors of 0.48 ± 0.007 cGymV. …

Radiation Monitoring In Mixed Environments At Cern: From The Irrad6 Facility To The Lhc Experiments, F Ravotti, M Glaser, Anatoly B. Rosenfeld, Michael L. Lerch, A Holmes-Siedle, G Sarrrabayrouse

Michael L.F. Lerch

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 …