Chayes L., Shlosman S.B., Zagrebnov V. A.
Discontinuity of the Magnetization in Diluted $O(n)$--Models.
(554K, Postscript)

ABSTRACT.  We study the annealed site--diluted versions of the classical $O(n)$
Heisenberg ferromagnets. It is shown that if the temperature is low enough,
then at some value of the chemical potential there is phase coexistence
between a magnetized, high--density state (liquid-crystal state) and a low
density state (gaseous state) with no magnetic order.