New Measurements of the Isotopic Composition of Galactic Cosmic Ray Elements Cu, Zn, Ga, Ge, As and Se*

The Cosmic Ray Isotope Spectrometer (CRIS) instrument on the NASA Advanced Composition Explorer (ACE) satellite was launched in August, 1997, and has collected data over this $\sim$22 year period of time. The large geometrical factor of the instrument, combined with the very long exposure time, has enabled us to measure the cosmic ray isotopic abundances of $_{31}$Ga, $_{32}$Ge, $_{33}$As, and $_{34}$Se for the first time, and to greatly improve earlier published measurements for $_{29}$Cu and $_{30}$Zn. We have collected a total of more than 1100 nuclei with Z=30 or greater, with energies in the range of $\sim$150 to 600 MeV/nucleon. In this paper we report preliminary isotopic cosmic-ray composition measurements and compare the observed isotopic fractions with those in the solar system.