Comparison of the angular distributions of the cosmic radiation at elevations 6280 ft. and 620 ft.

✍ Scribed by Thomas H. Johnson

• Publisher: Elsevier Science
• Year: 1933
• Tongue: English
• Weight: 410 KB
• Volume: 216
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/s0016-0032(33)91149-7

✦ Synopsis

Spacing between Counters

(h).

13 cm.

18 cm.

Thick

ness of Lead (t). 5 Cm. I0 cm. Total Counting Period. 1228 min. I072 1993 I497 Total Double Counts (D). 2289 2389 2074 2014 Total Triple Counts (T). 1913 I954 I73I I615 T/D. o.84+o.oi with lead o.82:t:o.oi without lead 0.844-O.01 with lead o.8~ ±o.o1 without lead panied by at least one of its secondary ionizing rays. This latter possibility must be excluded on other grounds. In the first place, the groups observed in the cloud chamber seldom contain more than two ionizing rays, and in the second place, a comparison of ionization measurements with counter data indicates an average of only two to three ionizing rays per group. These considerations necessitate the conclusion that if the primary is a non-ionizing ray it would be unaccompanied by ionizing secondaries over such a large fraction of its path that P would be less than unity by an easily detectable amount. (If three were the average density of independently formed secondaries 2o per cent. of the path of the primary should be non-ionizing.) We are, therefore, left with the conclusion that all of the groups observed in the first experiment arise from an ionizing primary. This ray, of course, may itself have been produced by a non-ionizing gamma-ray or neutron and, furthermore, it is still possible that a part of the groups observed by other arrangements of counters or in the cloud chamber may arise according to postulate II. We are indebted to Dr. E. C. Stevenson for his help in arranging the circuits and in recording the data. COMPARISON OF THE ANGULAR DISTRIBUTIONS OF THE COSMIC RADIATION AT ELEVATIONS 6280 FT. AND 620 FT.*