[vsnet-chat 7487] TT Ari faint: QPOs still present

[Ivan Andronov]

In the [vsnet-alert 11543] , 	
MAEDA Yutaka reported that "TT Ari is faint" (12.9), what was confirmed by  Hiroyuki Maehara [vsnet-alert 11544] (13.0).

Alexej Baklanov continued observations of the star starting from September (Crimean Astrophysical Observatory, 38 cm)
The light curve in R (variable-"d" from Goetz 1987, http://www.konkoly.hu/cgi-bin/IBVSpdf?2823) is shown in an attached figure. Although the 
linear fit shows an apparent trend of  0.011(8) mag/day, i.e. NOT statistically significant during 3 subsequent night of observations. The V mag 
during the recent night (observations are still continued) is 12.84-13.32.

The light curves exhibit quasi-periodic oscilations, which are characteristic for the "negative superhump" state, contrary to the "positive 
superhump" state (cf. Kim et al., http://cdsads.u-strasbg.fr/abs/2009A%26A...496..765K)

This "negative superhump state" was observed also during the optical set simultaneous with the Suzuku satellite
http://cdsads.u-strasbg.fr/abs/2009ATel.2122....1A

So, till now, there was no switch to the "positive superhump state", although the mean brightness decreased by ~2 mag compared with usual 
maximum state.

Further monitoring of this interesting object is needed; in R or VRVR time series for all available nights.

Alexej Baklanov
Crimean Astrophysical Observatory, Ukraine

Ivan Andronov
Odessa National Maritime University, Ukraine
temporararily also (SAIA fellowship) Astronomical Institute, Slovak Academy of Sciences, Slovakia
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