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Il Nuovo Cimento (1955-1965)

, Volume 19, Issue 1, pp 6–19 | Cite as

Magnetic mirrors in the milky way galaxy

  • L. Marshall
Article
  • 18 Downloads

Summary

It is shown that the present day velocity distribution of the Milky Way Galaxy amplifies the magnetic field in the galactic arms by stretching the existing lines of force in such a way as to produce magnetic mirrors in the regions between 4 and 10 kps radius. The strength of the mirrors is increasing with time so that, effectively, a mirror of given strength seems to be moving out along the arm. It is suggested that these mirrors, fixed at constant radius but effectively moving, are important in production of cosmic rays, and it is shown that the appropriate constants relating to the mirrors are compatible with a Fermi accelerator mechanism of first order dependence on effective mirror velocity. The energy for this process is derived from differential rotation energy of which there is an adequate supply.

Riassunto

Si mostra che l’attuale distribution di velocità della Via Lattea amplifica il campo magnetico nei bracci galattici stirando le esistenti linee di forza in modo da formare specchi magnetici nella regione fra 4 e 10 kps di raggio. La forza degli specchi cresce col tempo cosicchè, in effetti, uno specchio di forza data sembra muoversi verso l’esterno lungo il braccio. Si avanza l’ipotesi che questi specchi, fissi ad un raggio costante ma che in effetti si muovono, abbiano importanza nella produzione dei raggi cosmici, e si mostra che le opportune costanti riferentisi agli specchi sono compatibili con un meccanismo acceleratore di Fermi con dipendenza di primo ordine dalle velocità effettive dello specchio. L’energia per questo processo è derivata dall’energia differenziale di rotazione di cui si ha un rifornimento adeguato.

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Copyright information

© Società Italiana di Fisica 1961

Authors and Affiliations

  • L. Marshall
    • 1
  1. 1.Rookhaven National LaboratoryUpton

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