2018MNRAS.476..554S

The X-ray spectra of intermediate polars can be modelled to give a direct measurement of white dwarf mass. Here, we fit accretion column models to NuSTAR spectra of three intermediate polars; V709 Cas, NY Lup, and V1223 Sgr in order to determine their masses. From fits to 3-78 keV spectra, we find masses of M_ WD_=0.88+0.05^_–0.04 M_☉, 1.16^+0.04_–0.02 M_☉, and 0.75 ± 0.02 M_☉ for V709 Cas, NY Lup, and V1223 Sgr, respectively. Our measurements are generally in agreement with those determined by previous surveys of intermediate polars, but with typically a factor ∼2 smaller uncertainties. This work paves the way for an approved NuSTAR Legacy Survey of white dwarf masses in intermediate polars.