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Long-term photometric behavior of the eclipsing cataclysmic variable V729 Sgr

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 نشر من قبل Zhongtao Han
 تاريخ النشر 2017
  مجال البحث فيزياء
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We present the analysis results of an eclipsing cataclysmic variable (CV) V729 Sgr, based on our observations and AAVSO data. Some outburst parameters were determined such as outburst amplitude ($A_{n}$) and recurrence time ($T_{n}$), and then the relationship between $A_{n}$ and $T_{n}$ is discussed. A cursory examination for the long-term light curves reveals that there are small-amplitude outbursts and dips present, which is similar to the behaviors seen in some nova-like CVs (NLs). More detailed inspection suggests that the outbursts in V729 Sgr may be Type A (outside-in) with a rise time $sim1.76$ d. Further analysis also shows that V729 Sgr is an intermediate between dwarf nova and NLs, and we constrain its mass transfer rate to $1.59times10^{-9} < dot{M}_{2} < 5.8times10^{-9}M_{odot}yr^{-1}$ by combining the theory for Z Cam type stars with observations. Moreover, the rapid oscillations in V729 Sgr were detected and analyzed for the first time. Our results indicate that the oscillation at $sim 25.5$ s is a true DNO, being associated with the accretion events. The classification of the oscillations at $sim 136$ and $154$ s as lpDNOs is based on the relation between $P_{lpDNOs}$ and $P_{DNOs}$. Meanwhile, the QPOs at the period of hundreds of seconds are also detected.



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