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Antiprotons at Solar Maximum

John W. Bieber·R. A. Burger·Ralph Engel·Thomas K. Gaisser·Stefan Roesler·Todor Stanev
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Abstract

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.

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John W. Bieber, R. A. Burger, Ralph Engel, Thomas K. Gaisser, Stefan Roesler, Todor Stanev. 1999-03-10. Antiprotons at Solar Maximum. https://doi.org/10.1103/physrevlett.83.674

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