Face-on, stream-fed intermediate polars: an alternative model for RX J1914.4+2456 and RX J0806.3+1527

We suggest that RX J1914.4+2456 and RX J0806.3+1527, recently proposed as double degenerate binaries with orbital periods of 569s and 321s respectively, may instead be the first examples of face-on, stream-fed intermediate polars. In each case, the X-ray modulation periods then represent the rotation of the white dwarf in the binary reference frame. The model explains the fully modulated X-ray pulse profiles, the antiphase between X-ray and optical/infrared modulation, the lack of longer period modulation, and the lack of polarization. Spectra of RX J0806.3+1527 suggest that Balmer series lines are present, blended with HeII lines, which rules out the double degenerate model for this object. The lack of optical/infrared emission lines in RX J1914.4+2456 may be attributed to a high mass accretion rate and its face-on orientation. We suggest its recently reported period decrease is a short term spin-up episode also driven by the current high $\dot{M}$.