BIPM - Ge spectrometers

Summary

Setting up an ionization chamber to be calibrated against the BIPM primary standard

Setting up a low-energy x-ray transfer chamber to compare with the BIPM standard

Primary standard for medium-energy x-radiation

Setting up a transfer chamber for radiation protection level quantities

NMI transfer chamber in a waterproof envelope inside the BIPM water phantom

Ionization chambers of the International Reference System (SIR)

The SIR experimental facilities in their new location

Efficiency curve of the SIR

Ge spectrometers

Proportional counters

Direct access

• BIPM METROLOGY PORTAL
• USEFUL LINKS
• ACRONYMS
• CIPM MRA
• KCDB
• JCTLM DATABASE
• MEETINGS
• CC DIRECTORY
• BIPM STAFF DIRECTORY
• PRACTICAL INFORMATION
• THE TIME
• METROLOGIA
• FUNDAMENTAL PHYSICAL
CONSTANTS

The Ge(Li) gamma -ray spectrometer (on the right) is calibrated in efficiency for SIR-type ampoules positioned in a Plexiglas holder at distances of 20 cm and 50 cm. The relative standard uncertainty of the full-energy peak efficiency is less than 0.5 % between 100 keV and 1.5 MeV. Its efficiency is slowly decreasing, probably because of a progressive reduction of the Ge(Li) active volume. The extended range p-type HPGe detector (on the left) is twice as efficient and allows x-ray measurements as it has a thin Be window. Its calibration in efficiency up to distances of 80 cm is in progress.