On the Nature of Superhumps

• Autorzy: Smak J.
• Języki publikacji: EN

Abstrakty

EN

Further evidence is presented supporting the alternative interpretation of superhumps as being due to irradiation modulated periodically variable mass transfer rate. NZ Boo, HT Cas and PU UMa are added to the sample of high inclination dwarf novae showing - during their superoutbursts - modulation of the observed brightness of the disk with beat period. Simple model calculations confirm earlier hypothesis that this modulation is due to a non-axisymmetric structure of the outer parts of the disk, involving the azimuthal dependence of their geometrical thickness, rotating with the beat period. The modulation amplitude A_mod is found to decrease during superoutbursts. In particular, it is found that during two superoutbursts of OY Car the rate of decline of the superhump amplitude dA_SH/dt was correlated with the rate of decline dA_mod/dt. This leads to a simple explanation for the decreasing amplitudes of superhumps: it is a consequence of the decreasing modulation amplitude.

Słowa kluczowe

EN

accretion; accretion disks; novae; cataclysmic variables; stars: dwarf novae; stars: individual: NZ Boo; stars: individual: OY Car; stars: individual: HT Cas; stars: individual: DV UMa; stars: individual: PU UMa

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2013
• Tom: Vol. 63, No. 3
• Strony: 369--377
• Opis fizyczny: Bibliogr. 23 poz., tab., wykr.

Twórcy

autor

Smak J.

• N. Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland

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