Profound Effect of a Magnetic Field on the Phase Diagram of SuperfluidHe3

In the presence of a magnetic field the ${}_{}{}^3{}_{}{}^{}\mathrm{He} A$ phase is interposed between the normal liquid and the ${}_{}{}^3{}_{}{}^{}\mathrm{He} B$ phase for all pressures measured, including pressures below that of the polycritical point. This can be understood on the basis of known nuclear paramagnetic properties if at a given pressure both ${}_{}{}^3{}_{}{}^{}\mathrm{He} A$ and ${}_{}{}^3{}_{}{}^{}\mathrm{He} B$ have the same critical temperature and if there are plausible small differences in the heat capacties of the two phases.