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Actinide-85 High Purity Germanium (HPGe) Lung Monitor Detector

ACTINIDE-85 is a high-resolution, high-purity germanium detector designed specifically for lung burden and whole body counting applications. It is based on the PROFILE S8530, which employs a proprietary stable, thin front contact in order to maximize low energy efficiency.

  • 85-mm diameter and 30-mm thick HPGe detector with a Stable, Thin Front Contact (STFC) optimized for Actinide Bioassay measurements.
  • Large frontal active area with excellent photon sensitivity for photon energies above 3 keV.
  • Warranted Energy Resolution (FWHM) equal to or better than 500 eV at 5.9 keV.
  • Warranted Energy Resolution (FWHM) equal to or better than 700 eV at 122 keV.
  • Warranted Energy Resolution (FWHM) equal to or better than 1.9 keV at 1332 keV.
  • Warranted Peak to Compton ratio >55:1.
  • FW 0.1M/FWHM typically <2.0, FW0.2M/FWHM typically <2.9.
  • Can be used with LN2 free ICS Integrated Cryocooling System.
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  • More Information +

    The unique detector design combines large area and excellent energy resolution across a wide range of energy, with excellent peak shape, so important in analysis of complex spectra. The result is excellent sensitivity for the detection of small amounts of actinides such as uranium, plutonium, and americium, as well as higher energy fission products and naturally-occurring radioisotopes, in a distributed source such as the human lung. 

    The large frontal area (>54 cm2) of ACTINIDE-85 provides high geometrical detection efficiency and superior resolution performance in the lower energy range of actinides such as Pu, Am and U, below around 400 keV, while the crystal depth of 30 mm means good stopping power and excellent relative efficiency at higher energies. The excellent warranted energy resolution at 1.33 MeV, combined with exceptionally good peak shapes, means that the ACTINIDE-85 is the ideal detector solution  for analysis of fission products as well.

    In lung burden measurements, large diameter detectors allow better coverage of the lung; with ACTINIDE-85, critically important energy resolution is maintained. The special mechanical construction of the cryostat allows two, three, or four ACTINIDE-85 detectors to be placed very close to each other and in contact with the subject. This configuration gives the maximum possible detector efficiency for human lungs. The detector cryostat is made of selected and qualified low background material, based not only on radioactive background characteristics, but also on long-term reliability. The detector endcap is made of an ultra-low background, high-strength carbon fiber composite which provides greater than 85% transmission for photon energy above 15 keV and nearly 100% transmission for photon energy above 20 keV. To further assure and verify low background quality, each detector is placed inside a graded-Z shielding and a background spectrum is taken for 100,000 seconds after assembly. This spectrum is delivered with the detector.

    ORTEC ACTINIDE-85 detectors may be ordered in a variety of configurations to meet a variety of requirements for lung burden, body burden, and whole-body counting programs. ORTEC lung burden assessment systems allow independent detector positioning which provide for optimum detector placement and measurement efficiency. In general, positioning mechanisms should be made of carefully screened low-background materials and designed for ease of use and reliability.

    Cryostat and Dewar
    The standard ACTINIDE-85 is supplied with a 3.5 liter "high fill" dewar. Which provides a typical holding time of 48 hrs. 

    Mechanical Cooling Options
    The ORTEC ICS Integrated Cryocooling System can be employed as an alternative to liquid nitrogen to cool the ACTINIDE-85 detector.

    The use of LN2 is costly, time consuming, and (of particular concern for lung burden assessment) is potentially hazardous. In addition, the presence of LN2 can be intimidating to personnel.

    The ICS utilizes a vacuum hardened eliminating the need to fully thermal cycle the detector in the event of a partial warm-up. Investment in the ICS can be recovered in two to three years, yet the long lifetime and excellent reliability of the ICS will make the cooler last nearly as long as the detector itself. 

    Consult the factory for resolution performance with ICS integrated cryocooling systems. 
  • Options +

    SMART-1 Option  (-SMP)
    The SMART-1 option monitors and reports on vital system functions, and can save authentication codes and report the code at a later time. It has the high voltage included, so none of the instruments require an external high-voltage power supply. The SMART-1 is housed in a rugged ABS molded plastic enclosure and is permanently attached to the detector endcap via a molded-strain-relieved sealed cable. This eliminates the possibility that the detector will suffer severe damage from moisture leaking into high-voltage connectors. The SMART-1 can be positioned in any convenient place and does not interfere with shielding or other mounting hardware.
  • Ordering Information +

    Model Description
    ACT85 ACTINIDE-85 detector, CFG-GG-LB-C-108 low-background cryostat with Carbon Fiber endcap and DWR-3.5HF high-fill dewar.
    ACT85P4-RB ACTINIDE-85 detector in reduced background PopTop capsule with Carbon Fiber endcap for use with ICS Integrated Cryocooling System.
    -SMP SMART-1 detector option for positive bias detector, add "-SMP" to the model number [e.g., ACT85-SMP or ACT85P4-RB-SMP].