Context : Asteroseismic analysis of solar-like stars allows us to determine physical parameters such as stellar mass , with a higher precision compared to most other methods .
Even in a well-studied cluster such as the Hyades , the masses of the red giant stars are not well known , and previous mass estimates are based on model calculations ( isochrones ) .
The four known red giants in the Hyades are assumed to be clump ( core-helium-burning ) stars based on their positions in colour-magnitude diagrams , however asteroseismology offers an opportunity to test this assumption .

Aims : Using asteroseismic techniques combined with other methods , we aim to derive physical parameters and the evolutionary stage for the planet hosting star \epsilon Tau , which is one of the four red giants located in the Hyades .

Methods : We analysed time-series data from both ground and space to perform the asteroseismic analysis .
By combining high signal-to-noise ( S/N ) radial-velocity data from the ground-based SONG network with continuous space-based data from the revised Kepler mission K2 , we derive and characterize 27 individual oscillation modes for \epsilon Tau , along with global oscillation parameters such as the large frequency separation \Delta \nu and the ratio between the amplitude of the oscillations measured in radial velocity and intensity as a function of frequency .
The latter has been measured previously for only two stars , the Sun and Procyon .
Combining the seismic analysis with interferometric and spectroscopic measurements , we derive physical parameters for \epsilon Tau , and discuss its evolutionary status .

Results : Along with other physical parameters , we derive an asteroseismic mass for \epsilon Tau of M = 2.458 \pm 0.073 M _ { \odot } , which is slightly lower than previous estimates , and which leads to a revised minimum mass of the planetary companion .
Noting that the SONG and K2 data are non-simultaneous , we estimate the amplitude ratio between intensity and radial velocity to be 42.2 \pm 2.3 ppm m ^ { -1 } s , which is higher than expected from scaling relations .

Conclusions :