  The dependence of the cosmic ray intensity on Galactocentric distance is
known to be much less rapid than that to be thought-to-be sources: supernova
remnants. This is an old problem ('the radial gradient problem') which has led
to a number of possible 'scenarios'. Here, we use recent data on the
supernova's radial distribution and correlate it with the measured HII electron
temperature ({\em T}). We examined two models of cosmic ray injection and
acceleration and in both of them the injection efficiency increases with
increasing ambient temperature {\em T}. The increase is expected to vary as a
high power of {\em T} in view of the strong temperature dependence of the tail
of the Maxwell-Boltzmann distribution of particle energies. Writing the
efficiency as proportional to $T^n$ we find $n\approx 8.4$. There is thus, yet
another possible explanation of the radial gradient problem.
