GALACTIC COSMIC RAY ORIGINS AND OB ASSOCIATIONS: EVIDENCE FROM SuperTIGER OBSERVATIONS OF ELEMENTS 26Fe THROUGH 40Zr

• Published in: The Astrophysical journal Vol. 831; no. 2
• Main Authors: Murphy, R. P., Sasaki, M., Binns, W. R., Brandt, T. J., Hams, T., Israel, M. H., Labrador, A. W., Link, J. T., Mewaldt, R. A., Mitchell, J. W., Rauch, B. F., Sakai, K., Stone, E. C., Waddington, C. J., Walsh, N. E., Ward, J. E., Wiedenbeck, M. E.
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 10-11-2016; IOP Publishing
• Subjects: Abundance; Acceleration; Astrophysics; Atomic properties; Balloon flight; Cosmic dust; Cosmic ray models; Cosmic ray origin; Cosmic rays; Galactic cosmic rays; Galaxy: abundances; Interstellar dust; Interstellar gas; Interstellar matter; Interstellar medium; ISM: abundances; Massive stars; Radiation; Solar system; stars: winds, outflows; supernovae: general; Zirconium isotopes
• ISSN: 0004-637X; 1538-4357
• DOI: 10.3847/0004-637X/831/2/148

ABSTRACT We report abundances of elements from 26Fe to 40Zr in the cosmic radiation measured by the SuperTIGER (Trans-Iron Galactic Element Recorder) instrument during 55 days of exposure on a long-duration balloon flight over Antarctica. These observations resolve elemental abundances in this charge range with single-element resolution and good statistics. These results support a model of cosmic ray origin in which the source material consists of a mixture of % material from massive stars and ∼81% normal interstellar medium material with solar system abundances. The results also show a preferential acceleration of refractory elements (found in interstellar dust grains) by a factor of ∼4 over volatile elements (found in interstellar gas) ordered by atomic mass (A). Both the refractory and volatile elements show a mass-dependent enhancement with similar slopes.