We study the effect of the late decaying saxino (the scalar superpartner of
the axion) and find out that there is a possible dark matter solution from a
class of supersymmetric extensions of the invisible axion model. In this class
of models, the saxino which decays into two axions acts as the late decaying
particle which reconciles the cold dark matter model with high values of the
Hubble constant. Recent observations of the Hubble constant are converging to
H0=70−80kmsec−1Mpc−1, which would be
inconsistent with the standard mixed dark matter model. This class of models
provides a plausible framework for the alternative cold dark matter plus late
decaying particle model, with the interesting possibility that both cold dark
matter and the extra radiation consist of axion.Comment: 11 pages, no figure, REVTEX 3.
