Published online by Cambridge University Press: 15 February 2011
We report measurements of the hysteretic capillary condensation of liquid 4He into the porous material Nuclepore. Results are presented for global and hysteretic behavior for 300 Å diameter pores. These observations deviate from the predictions of the Preisach model of independent hysteresis domains. By modifying the Preisach model so as to restrict the ability of some of the pores to drain normally we are able to model many features of the experimental data.