1. Galactic Cosmic Ray Energy Spectrum for Fe from ~0
Galactic Cosmic Ray Energy Spectrum for Fe from ~0.8 to ~10 GeV/nuc with the SuperTIGER Instrument
A.W. Labrador (1*), W.R. Binns (2), R.G. Bose (2), T.J. Brandt (3), P.F. Dowkontt (2), T. Hams (3,6), M.H. Israel (2), J.T. Link (3,6), R.A. Mewaldt (1), J.W. Mitchell (3), R.P. Murphy (2), B.F. Rauch (2), K. Sakai (3,6), M. Sasaki (3,6), E. C. Stone (1), C.J. Waddington (4), J.E. Ward (2), and M. E. Wiedenbeck (5)
1. California Institute of Technology, Pasadena, CA USA;
2. Washington University, St. Louis, MO USA;
3. NASA/Goddard Space Flight Center, Greenbelt, MD USA;
4. The University of Minnesota, Minneapolis, MN 55455, USA:
5. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
6. Center for Research and Exploration in Space Science and Technology (CRESST), Greenbelt, MD 20771, USA

2. SuperTIGER “Super” Trans-Iron Galactic Element Recorder
A balloon-borne cosmic ray instrument that can measure galactic cosmic ray abundances for Z=~10–60 for energies ~ GeV/nuc
Primary Goals: Measure Z=30–60 abundances to test OB association models for cosmic ray origins
Secondary Goals: Spectra, spectral features
A clear picture is emerging of how cosmic rays originate in OB associations, regions of our Galaxy in which there are a number of young, short-lived, massive stars [19,20] that form superbubbles. The cosmic-ray source is understood as a mixture of old interstellar material with the outflow from massive stars (importantly including Wolf-Rayet stars and their precursor phases) and ejecta from core-collapse supernovae (SNII, SNIb,c), which occur mostly in OB associations. This model is supported by the 22Ne/20Ne and 58Fe/56Fe overabundances in the GCRs measured most recently by the CRIS instrument on ACE as well as the element ratio N/O [9,10]. In addition, elements that reside primarily in grains in interstellar space (refractory elements) are preferentially accelerated compared to those that reside primarily as gas (volatile elements), and this enrichment appears to be mass dependent for both refractories and volatiles. The mass-dependent element enrichment is supported by abundances measured by TIGER at GeV/nuc energies [23,24,28], ACE at energies of hundreds of MeV/nuc [21], and CREAM at TeV/nuc energies [2

3. SuperTIGER Jason Link [CRD139] - SuperTIGER, SuperTIGER 2
Nathan Walsh [CRD047] - SuperTIGER Z= abundances
ICRC 2015
Hams et al.; Sasaki et al. - CR origins
Murphy et al. –– Ultraheavy element analysis
Labrador et al. –– SuperTIGER Z=10-30 abundances

4. SuperTIGER

5. SuperTIGER
December 8, 2012 –– February 1, 2013

6. Line of Sight (LOS) Data
SuperTIGER
Line of Sight (LOS) Data

7. Microquasars
Heinz & Sunyaev (“Cosmic Rays from Microquasars: A Narrow Component to the CR Spectrum?”, Astron & Astrophys, 390 (2002) 751)
Suggested that relativistic jets observed in micro-quasars like GRS and GRO J might produce narrow features in some cosmic ray spectra.

8. Microquasar Hypothetical Signature
Fe Beam at 5 GeV/nuc, width 0.5 GeV/nuc
Interstellar model: A.Davis et al., JGR, A12, 29,979, 2001
Solar Modulation is spherically symmetric diffusion calculation after Fisk, JGR (1971).

9. Line of Sight (LOS) Data
SuperTIGER
Line of Sight (LOS) Data

10. Analysis — Energy Scaling
Aerogels n=1.043/n= (thresholds ~2.5 GeV/nuc, ~3.3 GeV/nuc)
Background signals move the zero Cherenkov signal point
knock-ons
Scintillation
Goretex Cherenkov

11. Analysis — Energy Scaling
Aerogels n=1.043/n= (thresholds ~2.5 GeV/nuc, ~3.3 GeV/nuc)
Background signals move the zero Cherenkov signal point
knock-ons
Scintillation
Goretex Cherenkov

12. The Analysis Done Energy scaling Energy shifts
TO DO (after the Conference)
Livetime and instrument efficiency
Interaction loss corrections
Deconvolution

13. Fe Scaled Spectrum
ACE Data (open triangles) from ACE Science Center ( for the same dates as the SuperTIGER data.
Interstellar model: A.Davis et al., JGR, A12, 29,979, 2001
Solar Modulation to 575 MV.

14. Fe Scaled Spectrum

15. Conclusions
SuperTIGER spectrum calculations are under way, though final calculations from the first flight will likely wait until after the conference.
Even without absolute intensities, we have sufficient statistics with a sample of data to eliminate large, narrow microquasar signatures in Fe (e.g. 5 GeV/nuc beam, 0.5 GeV/nuc width).
Additional scaled spectra will be reported in the final version of this paper.