SuperTIGER Abundances of Galactic Cosmic-Rays for the Charge Interval Z=41-56

ORAL

Abstract

On December 8, 2012 the SuperTIGER (Super Trans-Iron Galactic Element Recorder) instrument was launched from Williams Field, Antarctica on a long-duration balloon flight that lasted 55 days and maintained a mean altitude of 125,000 feet. SuperTIGER measured the relative abundances of Galactic cosmic-ray nuclei with high statistical precision and well resolved individual element peaks from Neon to Zirconium (charges Z=10-40). SuperTIGER also made exploratory measurements of the relative abundances up to Barium (Z=56). Although the statistics are low for elements heavier than Zirconium, we will show how the relative abundances of charges Z=41-56 compare to those reported by HEAO3-HNE during 1979-81. The relative abundances of elements Zirconium through Neodymium (Z=60) are of particular interest because they are likely formed both by supernova explosions and by binary neutron star mergers. A well resolved measurement of this range of elements can constrain the contributions to the Galactic cosmic-ray composition from both of these possible sources.


*This research was supported by NASA under grants NNX09AC17G and NNX14AB25G, by the McDonnell Center for the Space Sciences at Washington University, and by the Peggy and Steve Fossett Foundation.

Presenters

  • Nathan Elliot Walsh

    • Washington University in St. Louis

Authors

  • Nathan Elliot Walsh

    • Washington University in St. Louis