New measurement of the cosmic-ray positron fraction from 5 to 15 GeV.

@article{Beatty2004NewMO,
  title={New measurement of the cosmic-ray positron fraction from 5 to 15 GeV.},
  author={James J. Beatty and Amit Bhattacharyya and Charles Bower and St{\'e}phane Coutu and M. A. Duvernois and Sean McKee and Sharon Minnick and Dietrich M{\"u}ller and Jordan Musser and Sharon Nutter and A. W. Labrador and Michael Schubnell and Simon P. Swordy and Gregory Tarl{\'e} and Andrew D. Tomasch},
  journal={Physical review letters},
  year={2004},
  volume={93 24},
  pages={241102}
}
We present a new measurement of the cosmic-ray positron fraction at energies between 5 and 15 GeV with the balloon-borne HEAT-pbar instrument in the spring of 2000. The data presented here are compatible with our previous measurements, obtained with a different instrument. The combined data from the three HEAT flights indicate a small positron flux of nonstandard origin above 5 GeV. We compare the new measurement with earlier data obtained with the HEAT-e(+/-) instrument, during the opposite… CONTINUE READING