Heat capacity of 3He in aerogel -: art. no. 115301

The heat capacity of pure He-3 in low density aerogel is measured at 22.5 bars. The superfluid response is simultaneously monitored with a torsional oscillator. A slightly rounded heat capacity peak, 65 muK in width, is observed at the He-3-aerogel superfluid transition, T-ca. Subtracting the bulk He-3 contribution, the heat capacity shows a Fermi-liquid form above T-ca. We can fit the heat capacity attributed to superfluid within the aerogel with a rounded BCS form accounting for 0.30 of the nonbulk fluid in the aerogel, or by assuming a substantial reduction in the superfluid order parameter. Both approaches are consistent with earlier superfluid density measurements.