The measuring system LB 761 GD α-β Low-Level Counter for 200 mm Planchets allows the simultaneous measurement of α- and β- activity of a sample in two separate measuring channels. The background count-rates of the system LB 761 are extraordinarily low, so that good detection limits can be achieved.
Specifications
| Components | ||
| Counter: | LB 6307 with sample tray | |
| Lead shielding: | 10 cm thickness with 78 standard bricks, and 4 bricks machined, 4 pi shield to reduce ambient radiation.Weight approx. 800 kg |
|
| Alpha-Beta Discriminator: | LB 2028-1 | |
| Counting gas: | Standard P-10 gas (Argon-Methane 90:10) | |
| Operating voltage: | Measuring counter | 1300 V 1700 V |
| Shielding counter | ||
| Window: | Hostaphan-foil, alu- steamed on both sides 0.4 mg/cm² | |
| Efficiency for extended soures (sources 200 mm Ø, surface 11 mm each below upper edge of the tray, the efficiency can be inreased by placing the α-source on a higher level) |
241Am 90Sr/90Y 14C |
18% 46% 26% |
| Background (measured with a 200 mm tin-plated planchet) |
α-channel β-channel |
approx. 0.02 cps approx. 0.15 cps |
| Spillover | β- in α-channel α- in β-channel |
< 0.01 α-counts per 1000 β-counts depending on the type of nuclide and on self- absorption of the source. Typical value for 210Po 2 % |
| Dimensions of the counting chamber including shieldi |
270 x 600 x 600 mm³ (H x W x L) | |
