Aerosol mass determination with nuclear track filters from quartz crystals

Irradiating quartz crystals of approx. 100 mym thickness with heavy ions (eg. 238U, 17 MeV per nucleon, 10 E5 ions cm E-2) creates heavy damage of the crystal structure along the path. Etching these quartzes with KOH, for example, produces pores with adjustable diameter. The possibility of using these quartzes as filtering mass monitoring devices was investigated. As a result a reduced Q-factor compared to untreated quartzes was obtained but the quartzes still can be employed as oscillators. Their moisture sensitivity and temperature coefficients are similar to those of normal quartzes. Their typical mass response is approx. 1 Hz ng E-1 cm E-2. The pores have a funnel shape so that cascading to obtain mass size distributions is difficult. (ITA)