**Supersonic Solutions of the Solar-Wind Equations for Low Coronal Temperatures**

**J. W. Chamberlain (Rice University)**

I have examined the solutions of the three hydrodynamic solar-wind
equations for the low-energy wind developed by Durney and for the
supersonic ``breezes'' identified by Roberts and Soward. (The breezes
are defined by the condition that , the flux of kinetic
and conductive energy at infinity, vanishes.) These low-energy
domains may have more relevance to planetary blowoff than do the more
familiar high-energy solutions in the Parker domain. The low-energy cases admit a
``formal solution'' for the temperature and expansion velocity, discovered
in 1961 but not previously exploited. In the Durney solutions, the temperature
gradient at infinity is no longer easily obtained from the *conductivity parameter,
A,* since conduction has ceased to be important at large distances from the
coronal base.

The Durney solutions extend from the Parker domain to the domain of supersonic breezes,
where the variation of coronal temperature, , with *A*, curiously
reverses sign. Consequently, there are two supersonic solutions for values of the ratio
(thermal-energy)/(gravitational-energy) = in the range
between 0.33333 and about 0.32865. One solution exists for
= 0 (a solar breeze) and another for a Durney solar wind, with a different,
somewhat larger value of *A* (or, equivalently, a smaller coronal
density). Calculations of temperature and velocity profiles illustrate
a distinguishing behavior for each energy domain.