Beschreibung:
<jats:title>Abstract</jats:title><jats:p>Using a simple but nevertheless sensitive experimental arrangement the ac susceptibility of HoAsO<jats:sub>4</jats:sub> was studied near its paramagnetic to antiferromagnetic phase transition at <jats:italic>T</jats:italic><jats:sub>N</jats:sub> = 0.559 K. By these measurements concerning with the temperature and the magnetic field dependence of the susceptibility Fisher's theory connecting the specific heat and the reduced susceptibility of an antiferromagnet could be verified. Both the exchange and dipolar fields are given.</jats:p>