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The first phase of LADD has transformed the landscape for radiation detection R&D projects related to basic physics, medical imaging, and infrared (IR) astronomy applications at TRIUMF, Canada’s National Laboratory for nuclear and particle physics research and at UM. Prior to LADD, most of the equipment available for detector development was obtained 10 - 20 years ago and required replacement in order for high precision detector development and research to be viable. LADD has revitalized or newly established the equipment base in 1400 sq. m of lab space at TRIUMF consisting of detector test areas, clean rooms, machine rooms, electronics labs, a cryogenics lab, and storage areas. At UM, a low level radioactive contamination laboratory and clean room including a large water purification system has been established along with an extensive electronics test laboratory, and a specialized laboratory for IR astronomy devices. Diverse projects benefiting from these developments include particle physics experiments (KOPIO, T2K, and PICASSO), nuclear physics experiments (ISAC), condensed matter research (µSR), IR astronomy, and medical imaging research (PET). At the UBC-TRIUMF site, new air (AC/exhaust) systems have been provided to clean- rooms, fabrication areas, and test areas to boost the clean air flow to the required environmental and safety levels. Overhead crane systems have been provided to allow large delicate detector components to be handled properly. Optical systems, lasers, a fiber optic handling and splicing machine, advanced photo-sensors (photo-multipliers (PMs), avalanche photodiodes (APDs), and silicon photomultipliers (SiPMs)) have been acquired for use in various advanced R&D projects. Metal piping of mixed gases to clean rooms and test areas has been installed to maintain purity of gases for high precision detectors. Sensitive gas handling and analysis systems including a quadrupole mass spectrometer have been acquired and installed. Specialized electronics design and testing systems capable of dealing with the unique signal processing characteristics of high speed detector systems have been developed, acquired, and installed, and these systems are already in use by several projects at both LADD sites. Front-end amplifiers and precision pulse shaping networks have been developed along with on-board field programmable logic devices to provide solutions for achieving the high speed analog signal processing that is required for many applications using advanced detectors. In order to evaluate and develop forefront systems such as new PET detectors, substantial new electronics design, test, and measurement infrastructure including hardware and software, a low-high temperature environment chiller/oven, high precision and high speed pulsers, state-of-the-art high bandwidth oscilloscopes, and other advanced equipment has been acquired and used. Electronics systems developed by the UM-UBC-TRIUMF collaboration using LADD resources (originally for KOPIO, which has now been terminated) has already seen extensive usage in other forefront projects including the TPC projects at Carleton University, Aachen University (Germany), data acquisition modules for the TIGRESS Doppler shift-corrected gamma spectrometer (TRIUMF-ISAC2), readout cards for the TACTIC detector (York U.K - TRIUMF), readout cards for the TIGRESS silicon auxiliary detector (St. Mary's University- TRIUMF), readout cards for the ALPHA detector (TRIUMF), and also special electronics for the VERITAS nuclear astrophysics collaboration (McGill, UCLA). In addition, machining instrumentation with state-of-the-art automation and precision capabilities has been included along with filtered air suction extraction systems. These setups enable a full range of detector construction materials to be processed such as delicate plastic scintillators and fibrous compounds like FR4. A customized large (2m x 2m) high-precision inspection-machining router system is being installed with digital encoders, camera/microscopes and edge finders to ensure detailed precision of the detectors produced. The machining areas have been equipped with sensitive temperature and humidity controls to maintain precision when performing meticulous tasks like measuring the positions of components to 5 microns when stringing large particle tracking chambers. The expenditures have supported design, engineering, machining, assembly, calibration and testing of the new facilities. In the course of work directed at research projects, LADD has generated new Canadian industrial capabilities. LADD scientists and engineers worked with CELCO Industries (Surrey BC) to develop new technology to produce precise large scale extruded plastic scintillation detectors with multiple holes for wave-length-shifting fiber readout; only Fermilab and an associated company in Illinois presently have such capabilities, opening up the possibilities of a new market for Canadian technology. In a similar vein LADD engineers stimulated Profile Inc. (Sydney BC) to produce larger size (e.g. 1.5m x 1.5m) copper-coated FR4 (fiber-glass epoxy) panels than any other facility world-wide opening up another new potential market. In the course of development of the innovative KOPIO “gamma camera” and other gamma ray imaging detectors, LADD work has produced four approved patents and two other pending patent applications. These inventions include a system for imaging 9 MeV gammas related to detection of plastic explosives, new gamma ray detector geometries for PET and other medical imaging applications, new systems to select true coincidence events in PET, and a radiation detection system applicable to geological tomography; some of these inventions are being pursued commercially. Spin-offs such as these provide further demonstration of the synergy between forefront fundamental science research and applications of the technologies generated to other pursuits. Numerous leading research efforts have been made possible by LADD infrastructure at the UBC-TRIUMF and UM sites. Examples presented below include new gamma ray imaging instrumentation for PET, neutrino interaction imaging, nuclear physics experiments, a dark matter search, condensed matter research, and new capabilities for infrared astronomy. Liquid xenon (LXe), replacing inorganic crystals commonly used in positron emission tomography (PET) as the gamma ray detection medium, is hypothesized to be superior to existing detector materials used in medical imaging for nuclear medicine applications. The LADD project aims to demonstrate that LXe detectors have the properties required for greatly improved sensitivity and image quality in nuclear medicine including sub-mm spatial resolution in all three dimensions and elimination of parallax errors. In addition, due to substantially faster time response for reduction of random coincidences and superior energy resolution (using both charge signals, and light output which is comparable with NaI(Tl)) with consequently reduced scatter fraction, the LXe PET system may produce images of higher overall quality. Because each energy-depositing interaction can be precisely recorded, application of LXe systems as coincidence Compton cameras for PET application is also feasible and is being investigated experimentally and with simulations. It is planned to explore new features of coincidence Compton cameras, including gamma ray polarization effects, which allow measurement of each incident photon angle for selecting true coincidences. Xenon is affordable (comparable in cost to NaI) and becomes liquid at -100 degrees C, which is above the temperature of liquid nitrogen, making liquefying it straightforward. Thus, engineering a practical medical imaging system appears to be feasible. This LXe work is being pursued vigorously by a collaboration of LADD scientists from UBC, TRIUMF, and UM. A new cryogenics imaging laboratory has been established at TRIUMF for the development of LXe (and other noble element) systems for PET, SPECT and other applications. The lab includes gas handling, cooling, purifying, monitoring, safety, and control apparatus (hardware and software), and a supply of xenon gas. A prototype gamma ray detector has been constructed and installed and initial electronics and light detection systems have been developed. For this lab and other LADD applications, several lasers and other advanced instrumentation have been acquired and installed; this capability has already generated development of a new laser- induced electron calibration source which may have numerous detector R&D applications. New low noise electronics solutions for charge readout and for APD light sensor readout are under development. A conceptual design for a real-time data processing engine that would perform preliminary position measurements at the high counting rates involved in medical tomography has been developed. In addition, a design is in progress for a micro- PET animal scanner using LXe technology developed by LADD. The performance of this device will be compared with a state-of-the-art commercial micro-PET scanner at the UBC Vancouver Hospital. LADD infrastructure enabled a forefront high technology Canadian contribution to the T2K neutrino project, which is the most ambitious new experiment dedicated to studying neutrino properties and which follows in the footsteps of the pioneering Canadian SNO solar neutrino experiment. The main LADD efforts are directed towards state-of-the-art T2K neutrino detection instruments, the Fine Grain Detector (FGD) and the Time Projection Chamber (TPC). LADD infrastructure was essential to perform R&D on a very promising new photo-sensor technology, Silicon Photomultipliers (SiPMs) which were acquired from Russia, tested at TRIUMF and which will have many other applciations. The TPC is a charged particle imaging detector in which ionization electrons are tracked using new micro-pattern avalanche devices, Gas Electron Multipliers (GEMs) obtained from CERN. LADD has provided expertise, simulation software, electronics infrastructure, readout electronics, and a complete laser test system. In addition, the LADD inspection-machining table will allow high precision machining of large scale components of the TPC. TPC and GEM technologies and associated electronic readout devices are also being studied by LADD collaborations at UBC- TRIUMF and UM for future use in detectors for the International Linear Collider (ILC), which is the world’s next major thrust in the field of high energy physics. The LADD radiation source scanning table has been used by the TIGRESS nuclear physics collaboration to measure the position-dependent pulse shape response of highly- segmented multi-crystal high-purity germanium detectors; these measurements confirmed that the noise-limited position sensitivity is well within the limits needed for Doppler reconstruction of gamma-ray events in important nuclear structure experiments at the new TRIUMF ISAC facility which is Canada’s world-leading enterprise in this field. The TRIUMF muon spin rotation (µSR) facility, unique in North America, provides extraordinary insight about the magnetic fields inside materials. The faciltiy relies on high quality muon beams together with state-of-the-art instrumentation to measure positrons emitted from muon decay. LADD infrastructure is aiding µSR physicists to optimize detector timing resolution by providing an advanced laser calibration system which provides a very short pulse (<70 ps) with a very short jitter used to obtain a timing resolution of 200 ps. Such a calibration system will also be used to investigate the timing performance of new photo-detectors such as SiPMs for the T2K and Linear Collider detector R&D. Many laboratories around the world are focusing on the construction of detectors for dark matter, which apparently makes up more than 90% of the matter in the universe but which is of an unknown nature. While various technologies to address this problem have been proposed the UM group has selected the superheated droplets technique which also has applications in radiation dosimetry. The construction procedure for detectors using superheated droplets has proven to be very successful and intermediate size prototype detectors have been built for the PICASSO experiment which is installed at SNOLAB in Sudbury, Ontario. Readout electronics to equip the prototype detectors have been designed and preliminary results are competitive with other leading approaches to the search for dark matter. LADD infrastructure allowed the UM Laboratoire d’Astrophysique Expérimentale (LAE) to become one of the most important university-based laboratories for the development and construction of astronomical instrumentation in Canada. The LAE played a key role in the development and construction of infrared (IR) instrumentation for the Canada- France-Hawaii Telescope (CFHT) with, for example, the recent construction of WIRCAM, the last state-of-the-art IR camera for the CFHT. It has developed a unique expertise in cryogenic IR instrumentation, strengthening the Herzberg Institute of Astrophysics (Victoria, BC) in optical/radio instrumentation. The LAE has also pioneered important new techniques in high-contrast imaging with applications to brown dwarf and exoplanet detection and it is actively involved in both the development of the James Webb Space Telescope and the Thirty Meter Telescope. The creation of experimental astrophysics laboratories in Canadian universities was one of the strongest recommendations of the Long Range Plan for Canadian astronomy. The optical astronomical instrumentation group at UM built the most sensitive optical photon counting camera (IPCS) FaNTOmM, based on a GaAs amplifier tube. The camera was used on four telescopes: the Observatoire du mont Mégantic 1.6m telescope in Québec, the Observatoire de Haute-Provence 1.8m in France, the Canada-France-Hawaii 3.6m telescope in Hawaii and the European Southern Observatory La Silla 3.6m telescope. An Australian collaboration to use it on the Siding Spring Observatory 2.3m telescope is being investigated. The velocity fields of more than 90 galaxies have been published and three theses were based on data from that camera. The LADD infrastructure allowed work to begin on FaNTOmM II camera, based on a new charged coupled device (CCD) integrated circuit. The UM group has also made significant contributions in the field of high-contrast imaging, first by quantifying the speckle noise problem and by proposing and implementing a novel multi-wavelength imaging technique for speckle suppression. UM pioneering work in this field has underscored the importance of speckle suppression in high-contrast imaging which is now recognized as a key requirement for the design of planet finder instruments.
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