a Measurement of the Antiproton Flux in the Cosmic Rays
Abstract
A balloon-borne instrument has been used to detect cosmic-ray antiprotons. These are identified topologically by the appearance of annihilation prongs in a thick lead-plate spark chamber. The initial recording of the data is enriched in potential antimatter events by a selective trigger. After a small subtraction for background, 14 identified antiprotons yield a flux of 1.7 plus or minus 0.00005 antiproton/(sq m ster sec MeV) between 130 and 320 MeV at the top of the atmosphere. When combined with higher energy antiproton flux measurements, this result indicates that the antiprotons have a spectrum whose shape is the same as that of the protons, but with a magnitude reduced by a factor of 1/3000.
- Publication:
-
International Cosmic Ray Conference
- Pub Date:
- 1981
- Bibcode:
- 1981ICRC....2...98B
- Keywords:
-
- Antiprotons;
- Balloon Sounding;
- Cosmic Rays;
- Proton Flux Density;
- Radiation Measurement;
- Data Recording;
- Energy Spectra;
- Spark Chambers;
- Upper Atmosphere;
- Space Radiation;
- ANTIPROTONS;
- BALLOON SOUNDING;
- COSMIC RAYS;
- PROTON FLUX DENSITY;
- RADIATION MEASUREMENT;
- DATA RECORDING;
- ENERGY SPECTRA;
- SPARK CHAMBERS;
- UPPER ATMOSPHERE