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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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