MCP-type ultra-high sensitivity thermoluminescent pellets are the latest development in radiation protection dosimetry. They are an important supplementary dosimetry tool to the standard LiF:Mg,Ti type pellets (MTS-N) especially for low-dose measurements and are unmatched in the range below tens of *Gy. Featuring a low, stable zero reading with a detection threshold of 50 nGy (200 times better than the standard LiF:Mg,Ti), they are 30 times more sensitive to gamma ray doses.
Our MCP-type ultra-high sensitivity detectors are solid circular pellets of 4.5 mm diameter with any required thickness in the range 0.3*1.5 mm (standard 0.9 mm).
The detectors consisting of 100% LiF:Mg,Cu,P TL phosphor are manufactured under the code name MCP (Mg, Cu, P), with an additional symbol, representing the isotopic content of lithium: MCP-N (natural abundance), MCP-6 (6Li-enriched), MCP-7 (7Li-enriched). The excellent dosimetric properties of the phosphor are enhanced by our original, carefully tested and controlled sintering procedure. The phosphor is also available in the form of powder.
The MCP chips are rather sensitive to thermal treatment which makes it important to use an annealing oven with good temperature stability. A summary of TL properties of MCP materials is given in the table overleaf.
The extremely high sensitivity of MCP detectors opens new possibilities in the study of very low doses, e.g., of the variations of natural background throughout the day or monitoring of doses of persons briefly visiting nuclear installations. In measurements of doses below 1 *Gy the natural gamma background should be taken into account.