Antiprotons at Solar Maximum

John W. Bieber, R. A. Burger, Ralph Engel, Thomas K. Gaisser, Stefan Roesler, and Todor Stanev
Phys. Rev. Lett. 83, 674 – Published 26 July 1999
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New measurements with good statistics will make it possible to observe the time variation of cosmic antiprotons at 1 AU through the approaching peak of solar activity. We report a new computation of the interstellar antiproton spectrum expected from collisions between cosmic protons and the interstellar gas. This spectrum is then used as input to a steady-state drift model of solar modulation, in order to provide predictions for the antiproton spectrum as well as the antiproton/proton ratio at 1 AU. Our model predicts a surprisingly large, rapid increase in the antiproton/proton ratio through the next solar maximum, followed by a large excursion in the ratio during the following decade.

  • Received 10 March 1999


©1999 American Physical Society

Authors & Affiliations

John W. Bieber1, R. A. Burger2, Ralph Engel1, Thomas K. Gaisser1, Stefan Roesler3, and Todor Stanev1

  • 1Bartol Research Institute, University of Delaware, Newark, Delaware 19716
  • 2Space Research Unit, School of Physics, Potchefstroom University for Christian Higher Education, 2520 Potchefstroom, South Africa
  • 3CERN, CH-1211 Geneva 23, Switzerland

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Vol. 83, Iss. 4 — 26 July 1999

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