A long-term photometric study of V 1184 Tauri

Abstract

Aims. The main purpose of our investigation is to construct the long-time light curve of the PMS star V 1184 Tau. We consider the study of the photometrical variability of PMS stars as very important for understanding stellar evolution. The unusual photometric variability of V 1184 Tau was reported in previous studies as well, but the nature of the observed deep minima is still under discussion. Methods. We present recent data from CCD photometry and from archival photographic plates. The photometric BVRI data presented in this paper were collected from November 2005 to November 2007. To construct the historical light curve of V 1184 Tau, a search for archived photographic observations in the Wide-Field Plate Database (WFPDB) was made. As a result, 412 photographic plates were found containing the field of V 1184 Tau. A part of the plates were scanned at our request and a magnitude estimation was made of V 1184 Tau. Results. Our recent photometric data suggest that the star brightness is still near the minimum. Thus the period of strong light variations that started in 2003 continues up to the present, hence more than 4 years. Our data from the archival photographic plates suggest that an unknown minimum of brightness exists in the approximate period 1980−1985. Taking all available photometric and spectroscopic data into account we must reject the hypothesis that V 1184 Tau is an FU Orionis type object. V 1184 Tau is a G type low-mass star whose spectrum is similar to WTT stars, but its photometric behavior is typical of the UX Orionis variable stars. Assuming the obscuration from orbiting dust clouds as a reason for a deep minimum, we estimate the approximate period of obscurations and the interval between two deep minima. Our calculations give a 25−28 year period between the two minima and approximately 8−10 year duration of the minima.

Optical photometry of GM Cep: evidence for UXor type of variability

“…Due to the complex circumstellar environment around PMS stars, such a mixture of different types of photometric variability can be expected. A similar superposition of two types of variability is seen on the long-term light curve of another PMS star V1184 Tau (Semkov 2006, Semkov et al 2008. But in this case the observed light curve is due to the phenomena of both: the typical for WTT stars periodic variability (Tackett et al 2003) and variable obscuration from UXor type (Barsunova et al 2006).…”

Photometric study of the FUor star V 1735 Cyg (Elias 1-12)

“…In some cases, stars originally classified as FUors in the detailed spectral and photometric study were identified as variables of other types. Such an example is the case with V 1184 Tau, initially considered as a FUor, but according to the recent published results it is more likely a star of UX Ori type (Barsunova et al 2006;Semkov et al 2008). The photometric data for V 1735 Cyg collected up to the present have confirmed its FUor classi- fication.…”

“…This should be an international cooperation study, because the archival photographic plates of this region have been stored in different countries. We are convinced that such a study would be very interesting and fruitful, as was the investigation of the suspected FUor star V 1184 Tau (Semkov et al 2008).…”

The pre-main-sequence star V1184 Tauri (CB 34V) at the end of prolonged eclipse

“…of observation, IRV B magnitudes of V1184 Tau, the telescope and CCD camera used. The mean values of instrumental errors of our photometric study are listed in Semkov et al (2008). In very deep minimums the star can be observed only in V, R, and I bands with the middle size telescopes (2-m RCC and 1.3-m RC) and only in R and I bands with the small telescopes (50/70-cm Schmidt and 60-cm Cassegrain).…”

“…In the third paper from our study (Semkov 2006), new data from optical photometry and spectroscopy of V1184 Tau in the period during the deep minimum are reported. In Semkov et al (2008), data from archival photographic plates are presented, which proves that an unknown minimum of brightness exists during the approximate period 1980-1985. Optical photometric data obtained at the time of our photometric monitoring have been published in Tackett et al (2003), Barsunova et al (2006), and Grinin et al (2009).…”