Long-range alpha detector (LRAD) technology, results, and applications

The usefulness of traditional alpha detectors for contamination monitoring is limited by the size and sensitivity of the detectors and by the short range of alpha particles in air. The long-range alpha detector (LRAD) detects the ions produced by the alpha particles passing through air, rather than the alpha particles themselves. Thus, LRAD detection is limited by the range of the ions (tens of meters), rather than the range of the alpha particles (a few centimeters). Since it collects all ions simultaneously, an LRAD monitor will be sensitive to all of the sources of contamination contained within it. In addition, the electronic noise within the LRAD can be reduced so that better sensitivity than that of traditional detectors is possible. Both soil surface and object monitors incorporate these advantages in their designs. Field-test results for these monitors are discussed