7Be, 10Be, and 36Cl in precipitation

Abstract

We have measured the cosmogenic radionuclides 7Be, 10Be, and 36Cl in mid-latitude precipitation collected in West Lafayette, IN. In the period April 18, 1992 to August 31, 1993, 350 samples were collected. A series of samples was collected through each precipitation event with 3 mm resolution. The 7Be/ 36Cl and 10Be/ 36Cl ratios vary by as much as a factor of 60 with a mean 10Be/ 36Cl ratio of 9.1. 7Be, 10Be, and 36Cl concentrations through a single event are correlated and typically decrease from high values at the beginning of an event to lower values at the end. Mean concentrations of 7Be, 10Be, and 36Cl are 1.4 × 10 7, 1.8 × 10 7, and 0.2 × 10 7 atoms/l.