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Is the old nova RW UMi (1956) an intermediate polar?

A. Bianchini·C. Tappert·H. Osborne·Ronald Canterna·F. Tamburini
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Abstract

From photometric observations of the old nova RW UMi (1956) we have discovered the presence of five sub-orbital periodicities. The longest period, P1 = 54.4 min, always observed, could be the beat period between the orbital period and the white dwarf (WD) spin period that we assume to be P2 = 33.4 min. The other suborbital periods could be orbital sidebands with respect to P2 and/or correspond to Keplerian resonance radii. We suggest that in its post-outburst state, characterized by higher mass transfer rate, RW UMi is an asynchronous intermediate polar with a truncated accretion disc. If the magnetic momentum of the WD is $μ_{34} \sim 0.8$, in its quiescent pre-outburst state, the nova would appear as a discless, synchronous intermediate polar.

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A. Bianchini, C. Tappert, H. Osborne, Ronald Canterna, F. Tamburini. 2001-07-31. Is the old nova RW UMi (1956) an intermediate polar?. https://arxiv.org/abs/astro-ph/0107583

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