Superoutbursts of Z Chameleontis. Detection of the Hot Spot

• Autorzy: Smak J.
• Języki publikacji: EN

Abstrakty

EN

Eclipse light curves of Z Cha collected during its superoutbursts are decomposed into the disk eclipse and spot eclipse components. It is found that the presence (or absence) of the hot spot and all its parameters depend on the phase φ_b of the beat period (related to the orbital and superhump periods). At beat phases 0.40<φ_b<0.60 the "standard" hot spot is present, the analysis of its parameters shows that (a) the mass transfer rate is strongly enhanced and (b) the radius of the disk is roughly equal to the tidal radius. No hot spot can be detected during eclipses located close to the superhump (beat phases 0.80<φ_b<0.35). The spot observed at intermediate beat phases (φ_b≈0.35 and φ_b≈0.75) shows peculiarities which are interpreted as being due to the stream overflow. Rediscussion of system parameters, based on the mass ratio obtained from the analysis of the spot eclipses during quiescence (Smak 1996) and K₂ from Wade and Horne (1988), gives: M₁=0.93±0.10 M_solar, M₂=0.186±0.030 M_solar, q=0.20±0.01 and i=80°.2±0°.3.

Słowa kluczowe

EN

Accretion; accretion disks; novae; cataclysmic variables; Stars: individual: Z Cha

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2007
• Tom: Vol. 57, No. 1
• Strony: 87--101
• Opis fizyczny: Bibliogr. 25 poz., rys., tab., wykr.

Twórcy

autor

Smak J.

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

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