Das Wesen der H�henstrahlung

History of Astroparticle Physics and its Components

“…The wire counter was the basis for another important development in cosmic-ray studies, the coincidence method, which was for the first time described by Bothe and Kohlhörster in 1929 [30]. This method makes use of the Geiger counter by connecting at least two of them.…”

The Nature of Statistical Fluctuations with Applications to Cosmic Rays

“…The number of counts per cm 2 per minute in a tube-counter near sea level is rather uncertain because of the difficulty of eliminating local Y-rays and radioactive contamination in the counter but it is near unity. Blackett and Occhialini 7 suggest 1.5 counts per cm 2 per minute, Bothe and Kolhorster 11 Heisenberg 18 suggest that the primary ionization by high energy electrons, such as cosmic-ray secondaries, should not exceed 50 to 60 ion pairs per cm in standard air unless the energy of the electron is far above 10 9 electron-volts.…”

The history of gamma-ray astronomy

“…But as we now know, this time period was ÒÓØ the hour of birth of -ray astronomy. In 1929 Bothe and Kolhörster discovered the corpuscular nature of the "high-altitude radiation" by means of two GeigerMüller counters in coincidence (Bothe & Kolhörster 1929), and it was still a long way to go until the first cosmic -rays were detected.…”