An improved method for determination of [sup.7]Be in mosses

We have measured [sup.7]Be activity in moss samples collected from in and around Mumbai, India. The use of heavily shielded Compton suppressor system is more efficient than the conventional gamma spectroscopic system for detection of [sup.7]Be. The [sup.7]Be accumulation capacities of mosses are more than other plant samples. Therefore monitoring of young moss samples by Compton suppressor system is an excellent tool for determination of atmospheric fallout of [sup.7]Be. A positive bias in the high altitude samples has been observed which might be due to any of the two reasons (i) higher cosmic ray flux in the high altitude or (ii) high pollution in the lower altitude area ultimately inhibits uptake of [sup.7]Be. Keywords [sup.7]Be * Compton suppressor system * Gamma-spectroscopy * Moss bio-monitoring