Low energy antiprotons in the cosmic rays: A new upper limit
Ahlen, S. P. ; Barwick, S. ; Beatty, J. J. ; Bower, C. R. ; Gerbier, G. ; Heinz, R. M. ; Lowder, D. ; McKee, S. ; Mufson, S. ; Musser, J. A. ; Price, P. B. ; Salamon, M. H. ; Tarle, G. ; Tomasch, A. ; Zhou, B.
Springer
Published 1989
Springer
Published 1989
| ISSN: |
1572-9540
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| Source: |
Springer Online Journal Archives 1860-2000
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| Topics: |
Physics
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| Notes: |
Abstract Kinematics predicts the severe suppression of low-energy (〈1 GeV) secondary antiprotons in the Galactic cosmic rays. Thus the observation several years ago of a finite flux of low-energy antiprotons could not be explained with existing models of cosmic ray propagation, which led to a plethora of theoretical speculation. We have recently flown a balloon-borne instrument to measure the energy spectrum of cosmic-ray $$\bar p's$$ , and have found no antiprotons in the energy interval 200–640 MeV (corrected to the top of the atmosphere). This yields an upper limit to the $$\bar p/p$$ ratio of 5.5×10−5 (90% confidence level), well below and hence contradicting the earlier result.
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| Type of Medium: |
Electronic Resource
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| URL: |