Co/Ni Ratio in Galactic Cosmic Rays: Results from the TIGER-2001 Flight

The Trans-Iron Galactic Element Recorder (TIGER) has completed two successful Antarctic flights in December/January of 2001 and 2003. TIGER was designed to observe elements in galactic cosmic rays (GCR) ranging from 14 $\le $ Z $\le $ 40 over an extended energy range. Observations of the isotopes of Co and Ni at low energies, in particular, the observation of $^{59}$Ni and $^{59}$Co from the Cosmic Ray Isotope Spectrometer on Advanced Composition Explorer, indicate that a significant time delay ($>$7.6x10$^{4}$ yr) exists between nucleosynthesis and acceleration of GCRs. While TIGER is not able to resolve isotopes, observations of the elemental abundance of Co and Ni at energies higher than CRIS/ACE further constrain models for GCR acceleration and propagation. With a 2001 flight of nearly 32 days, TIGER collected sufficient statistics to study the Co/Ni elemental ratio over a wide range in energy from $\sim $0.8-5 GeV/nucleon. We present the Co/Ni ratio observed from TIGER's first successful Antarctic flight in 2001 and compare these results with previous observations and with the predictions from GCR propagation models.