1.2 - Statement of Requirements
1.2.1. The Unversity of Ottawa is pleased to invite qualified proponents to submit a proposal for an instrument upgrade that is needed
for ultra-low level radiometric measurements that can be applied to detect long-range transported emissions from nuclear
reactors, nuclear effluents, and is essential for radiometric dating in natural archives to assess historical contamination in the
environment. A major focus of our environmental research is the detection of ultra-low level concentrations of nuclear emission
and naturally-occurring radioisotopes, that can be measured to determine sediment accumulation rates and settling velocities
for suspended particles, especially important for tracking the fate of particle-associated chemicals in aquatic environments.
General Description:
The upgraded system will include an ultra-low level background germanium gamma detector (well-type), ultra-low level
background cryostat, pre-amplifier, digital signal analyzer, associated cables, all associated software, computer system,
warranty, service, installation and training. Existing infrastructure on site: 30 L dewar, lead shield and support table at customer
site (drawings included – Appendix J). Shield will require supplier modifications to permit the installation of the upgraded
detector and cyrostat.
The system must be an ultra-low configuration that significantly reduces background, maximizes efficiency and significantly
improves peak resolution. The upgraded detector’s well must a “blind” configuration with near 4 π geometry. The pre-amplifier
should be external or lead shielded to reduce electronic noise transfer. Detector must have a maximum energy resolution
FWHM of no more than 1.4 at 122 keV. Detector/cryostat must be ultra-low background, vertical dipstick configuration to
accommodate existing infrastructure: 30 L dewar, lead shield and support table at customer site (drawings included- Appendix -
J). Detector must accommodate an entrance portal of 90 mm and supplier must provide modified annular ring for optimal
installation. Ulta–low background detector must be largest available volume to maximize efficiency and meet above criteria for
sizing; suggested active volume range 120 – 200 cc.
The equipment will be located at University of Ottawa, Faculty of Science, Department of Biology, CAREG building. There is an
electromagnetic field (EMF) generated by greenhouse electronics in this room. Current position of existing lead shield is optimal
for counter measures of EMF. Additional counter measures for reducing floor transmittable vibrations are in place under the
existing infrastructure.
Specifications listed in Appendix A – Technical Specifications Compliance Form of this RFP are the mandatory minimum
requirements for the ultra-low background gamma spectrometer, well-type, system upgrade.
