  Whether the massive neutron star PSR J0348+0432 can become a hyperon star is
examined in the framework of the relativistic mean field theory by adjusting
the hyperon coupling constants. It is found that at the central baryon number
density of the massive neutron star PSR J0348+0432, the relative particle
number density of hyperons is smaller than those of neutrons and so it can not
change into a hyperon star. In its center, it is mainly composed of $\Lambda$,
$\Xi^{-}$ and a few $\Xi^{0}$. We also found that for the neutron star with a
maximum mass of 1.4 M$_{\odot}$, it can change into a hyperon star and the
hyperon star transition density is 0.668 fm$^{-3}$, at which the hyperons are
only composed of $\Lambda$. At its center, the hyperons are also only composed
of $\Lambda$ and the ratio of the hyperons is a little larger than that of the
neutrons. This illustrates that the NS1.4M$_{\odot}$ has just changed into a
hyperon star.
