Authors: J.A. Paquette F.M. Ipavich, S.E Lasley, P. Bochsler, and P.Wurz
Reference: Submitted Solar Wind 9 Paper
Abstract:
Chromium and Iron are two heavy elements in the solar wind with similar masses.
The MTOF (Mass Time Of Flight) sensor of the CELIAS investigation on the SOHO
spacecraft easily allows these two elements to be resolved from each other.
Using the ratio of these two elements minimizes the effects of uncertainties in
instrument efficiency. The first measurements of the abundance ratio are
presented here. The First Ionization Potential (FIP) of Chromium is 6.76 eV,
while the FIP of Iron is 7.87 eV. Since Cr and Fe have similar FIPs their ratio
should not be biased by the FIP effect which is well known in different solar
wind flows, and therefore the Cr/Fe ratio from the MTOF data should give a good
measure of the photospheric abundance ratio. We also compare it to the
meteoritic value.