Smooth orbit equivalence rigidity for dissipative geodesic flows

Let M be a smooth closed orientable surface. A Gaussian thermostat on M can be seen as the geodesic flow of a certain metric connection with torsion. These flows may not preserve any smooth volume form. We prove that if two Gaussian thermostats on M with negative thermostat curvature are related by a smooth orbit equivalence isotopic to the identity, then the two background metrics are conformally equivalent via a smooth diffeomorphism of M isotopic to the identity. We also give a relationship between the thermostat forms themselves. Finally, we prove the same result for Anosov magnetic flows.