Can the Rapid Braking of the White Dwarf in AE Aquarii Be Explained in Terms of the Gravitational-Wave Emitter Mechanism?
The spin-down power of the white dwarf in the close binary AE Aquarii significantly exceeds the bolometric luminosity of the system. The interpretation of this phenomenon in terms of the gravitational-wave emitter mechanism has been recently suggested by Choi & Yi. The basic assumption of their interpretation is that the spatially limited blobs or mounds of mass δm ~ 10-3 M☉ are present at the magnetic poles of the white dwarf. We show that the mounds of this mass can be confined by the magnetic field of the white dwarf only if the dipole magnetic moment of the star exceeds 4 × 1037 G cm3. Under these conditions, however, the magnetodipole losses of the white dwarf would exceed the evaluated spin-down power by 6 orders of magnitude. On this basis, we discard the possibility that the observed rapid braking of the white dwarf in AE Aqr can be explained in terms of the mechanism proposed by Choi & Yi.
A white dwarf in the state of an ejector
We analyze the possibility of observational identification of white dwarfs in the state of an ejector. Among the distinctive features of this class of objects are a high rate of rotational energy loss comparable to or higher than the observed luminosity of the object and nonthermal gamma-ray and/or radio spectra. The manifestations of the white dwarf in the close binary system AE Aquarii closely match these criteria. We show that most of the peculiar manifestations of this object in the hard spectral range and the observed pattern of mass transfer in the system can be explained in terms of a model in which the state of the white dwarf is classified as an ejector.
Cosmical Electrodynamics
Cosmical ElectrodynamicsFundamental Principles. By Hannes Alfvén and Carl-Gunne Fälthammar. Second edition. (International Series of Monographs on Physics.) Pp. x + 228. (Oxford: Clarendon Press; London: Oxford University Press. 1963.) 60s. net.