Low-Temperature Specific-Heat Anomaly of bccHe3

The specific heat of bcc ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ has been measured from 25 mK to near the melting curve, with particular attention given to the region of the low-temperature anomaly, $T\lesssim 500$ mK. Here we find that the specific heat has a term linear in $T$, in addition to the Debye $T^3$ term. From the specific heat at the lowest temperatures, for the larger—molar-volume samples, values of the exchange energy $J$ in agreement with previous results are found.