Spectropolarimetric Observations of the Recurrent Nova RS Oph

We report spectropolarimetric observations of the recurrent nova RS Oph obtained during four nights between 2017 July and 2018 July. In the wavelength range from 5000 Å to 8000 Å, we find the maximum degree of linear polarization PL(obs)=2.9%±0.09 at λ≈5600 Å and the position angle θ=47o.2±0o.9. We do not detect any variability of the degree of polarization and the position angle. At the time of our observations, there is no intrinsic polarization in RS Oph and the observed values represent the interstellar polarization.