Time-Dependent Measurements of Absolute Spectra for Ne to Cu by SuperTIGER as a Probe of Solar Modulation and Geomagnetic Rigidity Effects

SuperTIGER (Trans-Iron Galactic Element Recorder) is a large-area, balloon-borne cosmic-ray experiment designed to measure the galactic cosmic-ray abundances of elements from Z=10 to Z=56 at energies from ~0.8 to ~10 GeV/nuc. Measurements of ultra-heavy elements (Z>30) requires precise calibration from Z<30 elements, and we will report energy spectra at the meeting. SuperTIGER flew over Antarctica for 55 days in 2012-2013, and it flew a second flight of 32 days in 2019-2020. The long, separate flights allow the measured spectra to be used to examine solar modulation, atmospheric, and geomagnetic effects. The first flight occurred when the solar modulation parameter was ~520–650 MV, between solar minimum and solar maximum based on ACE/CRIS measurements, and during the second flight, it was ~200-250 MV, near solar minimum. We will show the effects of solar modulation at the lowest energies measured by SuperTIGER. Also, during the first flight, the instrument circumnavigated the South Pole with latitudes from ~77 degrees South to ~65 degrees South, while during the second flight, the instrument drifted much farther toward the Pole, to about 85 degrees South. We will attempt to show possible geomagnetic cutoff effects in the SuperTIGER spectra measurements.