XtRa (Extended Range) Ge Detector

Features

• Spectroscopy from 3 keV up
• Wide range of efficiencies
• High resolution – good peak shape
• Excellent timing resolution
• High energy rate capability
• Diode FET protection
• Warm-up/HV shutdown
• High rate indicator

Description

The CANBERRA XtRa is a coaxial germanium detector having a unique thin-window contact on the front surface which extends the useful energy range down to 3 keV. Conventional coaxial detectors have a lithium-diffused contact typically between 0.5 and 1.5 mm thick. This dead layer stops most photons below 40 keV or so rendering the detector virtually worthless at low energies. The XtRa detector, with its exclusive thin entrance window and with a Beryllium cryostat window, offers all the advantages of conventional standard coaxial detectors such as high efficiency, good resolution, and moderate cost along with the energy response of the more expensive Reverse Electrode Ge (REGe) detector.

The response curves (above) illustrate the efficiency of the XtRa detector compared to a conventional Ge detector. The effective window thickness can be determined experimentally by comparing the intensities of the 22 keV and 88 keV peaks from ¹⁰⁹Cd. With the standard 0.5 mm Be window, the XtRa detector is guaranteed to give a 22 to 88 keV intensity ratio of greater than 20:1. Aluminum windows are also available.

CANBERRA XtRa Ge detectors are available in a wide range of sizes. Consult the model list overleaf for detailed specifications.