The Momentum Distribution of Charged Cosmic Ray Particles Near Sea Level

• Main Author: Glaser, Donald Arthur
• Format: Others
• Language: en
• Published: 1950
• Online Access: https://thesis.library.caltech.edu/4026/1/Glaser_da_1950.pdf; Glaser, Donald Arthur (1950) The Momentum Distribution of Charged Cosmic Ray Particles Near Sea Level. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/QFA6-BT49. https://resolver.caltech.edu/CaltechETD:etd-10112002-115844 <https://resolver.caltech.edu/CaltechETD:etd-10112002-115844>

<p>A new measurement of the momentum distribution of high energy charged cosmic ray particles at sea level has been made by means of a technique involving the use of two cloud chambers and a large electromagnet. With about twice the precision of previous determinations, the spectrum is extended to a momentum of pc = 80 Bev. For the 1547 measureable sets of tracks recorded, the positive-negative ratio is 1.26 ± 0.06, Up to the highest momenta measured the differential spectrum falls off as 1/p^s with s = 2 very nearly. The positive excess and positive-negative ratio appear to be functions of momentum with the positives predominating at about 1.3 Bev. In other respects the positive and negative spectra are very similar.</p> <p>Although the effect is barely outside statistical uncertainty, there seems to be an anomolous dip in the momentum distribution at about 3 Bev. In addition to this there seems to have been a small diurnal variation in the spectrum during the time the experiments were performed, 1 Bev and 4 Bev particles being slightly favored during the day and 3 Bev and 7 Bev particles being favored at night. These effects are discussed and the present results are compared with data of other experimenters.</p>