Peremennye Zvezdy (Variable Stars) 33, No. 6, 2013
Received 11 July; accepted 17 July.
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|We present the results of our new observations of TYC 0075 01143 1, a recently discovered double-mode Scuti variable. We improved the frequencies and and pulsation amplitudes, detected the interaction frequencies , , and a possible nonradial frequency .|
Variability of TYC 0075 01143 1 = ASAS 042606+0126.4 was detected
in the ASAS-3 project (Pojmanski 2002). In the ASAS catalog, the
classification of the variable is EC/DSCT (a contact eclipsing
binary or a Scuti variable); a period
also given there. Kruslov (2011) confirmed that TYC 0075 01143 1
belonged to Scuti stars; he also detected the double-mode
character of brightness variations and suggested the following
Preliminary results from our new CCD observations were published by Khruslov et al. (2012). In the present paper, we use a much longer series of observations that made it possible to detect new interaction frequencies and a possible nonradial frequency, .
The finding chart (Fig. 1) identifies the variable star, comparison star, and check star. The comparison star was GSC 00075-01862 and the check star, GSC 00075-01079. The magnitudes of these stars in the GSC2.3 catalog are respectively and .
Our observations are available online in the html version of this paper.
|Mode||Frequency, c/d||-band semi-amplitude,||Period, days||Epoch, HJD|
The light curves of TYC 0075 01143 1 are displayed in Fig. 2. The -band range of TYC 0075 01143 1 is . The period ratio is typical of high-amplitude double-mode Scuti stars radially pulsating in the fundamental and first overtone modes (Petersen & Christensen-Dalsgaard 1996).
Fig. 2. The light curves of TYC 0075 01143 1. Upper panels: raw data; lower panels: the folded light curves with the other variation pre-whitened.
Along with the light curves, we present power spectra of TYC 0075 01143 1, for the raw data and after subtraction of the fundamental-mode oscillations (see Fig. 3). Figure 4 exhibits light-curve variations from one cycle to another during the same night, typical of high-amplitude double-mode Scuti variables.
The frequency is identified rather reliably, its amplitude is close to that for the frequency . The structure of the power spectra (Fig. 5) leaves no doubt that is a real frequency. However, we cannot completely rule out that the real frequency is a one-day alias of the tabulated , namely (the corresponding period being 00374673).
Acknowledgements: The authors are grateful to Dr. V.P. Goranskij for providing software for the light-curve analysis. We wish to thank M.A. Krugov for technical assistance during the observations and Dr. N.N. Samus for helpful discussions. This study was supported by the Russian Foundation for Basic Research and by the Programme "Non-stationary Phenomena of Objects in the Universe" of the Presidium of Russian Academy of Sciences.
Fig. 4. Observations of TYC 0075 01143 1 acquired during a single night of November 20, 2012 (JD 2456252).
Fig. 5. The power spectrum for the frequency . All the other detected frequencies were pre-whitened.
Khruslov, A.V. 2011, PZP, 11, 30
Khruslov, A.V., Samus, N.N., Kokumbaeva, R.I., Kusakin, A.V. 2012, Communications from the National Academy of Sciences of Kazakhstan, Physics and Mathematics Series, No. 3, 25
Petersen, J.O., Christensen-Dalsgaard, J. 1996, Astron. and Astrophys., 312, 463
Pojmanski, G., 2002, Acta Astronomica, 52, 397