  This paper determines the relative source spectra of cosmic ray H and He
nuclei using a Leaky Box model for galactic propagation and the observed
spectra of these nuclei from ~10 MeV/nuc to ~1 TeV/nuc. The observations
consist of Voyager 1 measurements up to several hundred MeV/nuc in local
interstellar space and measurements above ~10 GeV/nuc where solar modulation
effects are small by experiments on BESS, PAMELA and AMS-2. Using BESS and
PAMELA measurements which agree with each other, the observed spectra for H and
He nuclei and the H/He ratio are well fit by source rigidity spectra for both
nuclei which are ~P-2.24 over the entire range of rigidities corresponding to
energies between 10 MeV/nuc and several hundred GeV/nuc. In this case, the H/He
rigidity source ratio is 5.0 + 1. The recent and presumably more accurate
measurements of these spectra above 10 GeV/nuc made by AMS-2 do not entirely
agree with the earlier measurements, however. In particular the H spectrum is
found to be steeper than that of He by about 0.10 in the spectral exponent.
Using the same model for galactic propagation the AMS-2 data leads to source
spectra of H and He which are ~P-2.24 up to a break rigidity ~6-8 GV. At higher
rigidities the He source spectrum continues to be ~P-2.24 but the required
source spectrum for H steepens to an index ~P-2.36 above ~8 GV and, as a
result, the H/He source ratio decreases with increasing rigidity using the
AMS-2 data.
