JANUARY 15, 1934
Proceedings of the American Physical Society

Supernovae and Comic Rays

W. BAADE, Mt. Wilson Observatories and
F. ZWICKY, California Institute of Technology

Supernovae flare up in every stellar system (nebula) once in several centuries. The lifetime of a supernova is about twenty days and its absolute brightness at maximum may be as high as MVIS = - 19. The visible radiation, L, of a supernova, is about 108 times the radiation of our sun, that is, L = 3.78 x 1041 ergs/sec. Calculations indicate that the total radiation, visible and invisible, is of the order L = 3.78 x 1048 ergs/sec. The supernova therefore emits during its life a total energy E > 3.78 x 1053 ergs. If supernovae initially are quite ordinary stars of mass M < 1034 g, E/c2 is of the same order as M itself. In the supernova process mass in bulk is annihilated. In addition the hypothesis suggests itself that cosmic rays are produced by supernovae. Assuming that in every nebula one supernova occurs every thousand years, the intensity of the cosmic rays to be observed on the earth should be of the order s = 2 x 10-3 erg/cm2 sec. The observational values are about s = 3 x 10-3 erg/cm2 sec. (Millikan, Regener). With all reserve we advance the view that supernovae represent the transitions from ordinary stars into neutron stars, which in their final stages consist of extremely closely packed neutrons.