Spin-density relaxation in superfluidA13

We report measurements on the spin-density relaxation in the superfluid ${}_{}{}^3{}_{}{}^{}{A}_1$ phase as a function of temperature, pressure (3–28 bars), and magnetic field (0.75–14 kOe). The temperature dependence of the relaxation time shows an unexpected discontinuity near the middle of the phase and very close to $T_c$ (the zero-field transition temperature). The relaxation time changes only by about 30% over the pressure range measured. In the higher-temperature side of the phase the relaxation time is proportional to the applied field.