Photometric variability in FU Ori and Z CMa as observed by MOST

Abstract

Photometric observations obtained by the MOST satellite were used to characterize optical small scale variability of the young stars FU Ori and Z CMa. Wavelet analysis for FU Ori reveals the possible existence of several 2-9 d quasi-periodic features occurring nearly simultaneously; they may be interpreted as plasma parcels or other localized disc heterogeneities revolving at different Keplerian radii in the accretion disc. Their periods may shorten slowly which may be due to spiralling in of individual parcels toward the inner disc radius, estimated at 4.8+/-0.2 R_sun. Analysis of additional multicolour data confirms the previously obtained relation between variations in the B-V colour index and the V magnitude. In contrast to the FU Ori results, the oscillation spectrum of Z CMa does not reveal any periodicities with the wavelet spectrum possibly dominated by outburst of the Herbig Be component.

Accepted by MNRAS

References in corpus (5)

• The Hot Inner Disk of FU Ori
• Photometric variability of the T Tauri star TW Hya on time scales of hours to years
• The Differential Rotation of FU Ori
• Optical photometric and spectral study of the new FU Orionis object V2493 Cyg (HBC 722)
• Analysis of the MOST light curve of the heavily spotted K2IV component of the single-line spectroscopic binary II Pegasi

Cited by in corpus (15)

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• The New EXor Outburst of ESO-H-alpha~99 observed by Gaia ATLAS and TESS
• Stable and unstable accretion in the classical T Tauri stars IM Lup and RU Lup as observed by MOST
• Light curves of the latest FUor: Indication of a close binary
• Insights into the inner regions of the FU Orionis disc
• Photometric and spectroscopic variability of the FUor star V582 Aurigae
• Photometric and spectroscopic study of the EXor-like eruptive young star Gaia19fct
• Gaia 20eae: A newly discovered episodically accreting young star
• A multi-epoch, multi-wavelength study of the classical FUor V1515 Cyg approaching quiescence
• Color Variability of HBC 722 in the Post-Outburst Phases
• Reading between the lines: Disk emission, wind, and accretion during the ZCMa NW outburst
• Disc light variability in the FUor star V646 Puppis as observed by TESS and from the ground
• Gaia20bdk -- a new FUor in Sh 2-301 Star Forming Region