- ID:
- ivo://CDS.VizieR/J/A+A/403/675
- Title:
- UBV light curves of IU Aur
- Short Name:
- J/A+A/403/675
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The data files includes photometric observations of the eclipsing binary system IU Aurigae. New photometric observations were made on 13 nights at the Ankara University Observatory (AUO) in 1997/1998 by using a 30cm Cassegrain-Maksutov telescope. The detector was a single-channel, uncooled SSP-5 photometer equipped with Hamamatsu R1414 photomultiplier tube. Observational standard errors determined from check star (HD 35633 = SAO 58053) measurements are 0.014mag, 0.012mag, and 0.018mag in U, B, and V filters, respectively. A total of 966, 959, 947 original data and of 118, 117, 117 reduced (averaged) data points is included for each UBV filters, respectively.
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- ID:
- ivo://CDS.VizieR/J/A+A/409/959
- Title:
- UBV light curves of V477 Cyg
- Short Name:
- J/A+A/409/959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New and complete UBV light curves and times of minimum are presented for the Algol type eclipsing binary V477 Cygni (Sp. A3V+F5V, m_v_=8.5, P=2.347days). The binary orbit of the system is highly eccentric and the system shows an apsidal motion. Using the Wilson-Devinney method, two photometric models, without (MODEL A) and with (MODEL B) third-body light contribution to the total light of the system, are obtained. Period analysis also gives some slender evidence for the unseen third-body in the system with the orbital period of about 157 years. In the MODEL A approximation the apsidal motion period is obtained to be 371 years while it is about 434 years in the MODEL B approximation. The photometric mass ratio (q=0.75) is in good agreement with the spectroscopic value given by Popper (1968ApJ...154..191P). The masses we obtained are 1.80+/-0.10 solar masses and 1.35+/-0.08 solar masses and the radii are 1.60+/-0.03 solar radii and 1.42+/-0.03 solar radii for the primary and secondary components, respectively. Absolute dimensions have been compared with the models using a moderate amount of convective overshooting and mass loss given by Claret & Gimenez (1991A&AS...87..507C). In the logM-logR diagram both components are located above but close to the ZAMS. It is possible to say from the logTe-logL diagram that the secondary component is just coming to the main sequence while the primary is slightly evolved from the ZAMS. The theoretical evolutionary models give an age of 6.4x10^8^yrs for the system.
- ID:
- ivo://CDS.VizieR/J/A+A/369/960
- Title:
- UBV minima for RU UMi
- Short Name:
- J/A+A/369/960
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The near-contact system RU UMi with an F0 primary and a K5 secondary was observed in U, B and V wavelengths in May and July 1998, as well as in March, May and July 1999. Six new observed times of minima are given and a new ephemeris is proposed. The basic parameters of the system extracted by our observations were used for spot modelling of the light curves. A simple spot distribution was determined, based on a model with one relatively small cool spot on the surface of the secondary. Absolute elements were calculated and the evolutionary status was determined. Our data favor a semi-detached configuration, with the secondary filling its inner Roche lobe; the primary must also be near the limits of its lobe.
- ID:
- ivo://CDS.VizieR/J/PASP/108/338
- Title:
- UBV obs. of the contact binary BF Pavonis
- Short Name:
- J/PASP/108/338
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present UBV photoelectric observations of the W UMa star BF Pav obtained between 1987 and 1993. A time-of-minimum study allows detection of a likely period increase of about 0.015s/yr. The Wilson-Devinney code is employed to simultaneously model the B and V light curves for several fixed values of the mass ratio q. From the quality-of-fit of the different solutions an approximate value of q=1.4+/-0.2 is derived. Absolute values of masses, dimensions, and luminosities are estimated by means of standard mass-luminosity relations for main-sequence stars. The detected period variation determines a lower limit of 5x10^-7M_{sun}_/yr for the rate of mass transfer from the less-massive to the more-massive component. We speculate that BF Pav has recently become in contact and is now in a rapid phase of mass transfer.
- ID:
- ivo://CDS.VizieR/J/A+A/405/1087
- Title:
- UBV photometry and radial velocities of V497 Cep
- Short Name:
- J/A+A/405/1087
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New light and radial-velocity curves of V497 Cep, a binary in the open cluster NGC 7160, were obtained and the linear ephemeris of the system was refined to HJD(Min I)=(2446299.1596+/-0.0064)+(1.2028287d+/-0.0000015)dxE. The first light and radial-velocity curve solutions allowed us to derive the basic physical properties of this astrophysically important binary.
- ID:
- ivo://CDS.VizieR/J/AN/331/274
- Title:
- UBV photometry of early-type stars
- Short Name:
- J/AN/331/274
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- UBV measurements of early-type stars, mostly eclipsing binaries, obtained at La Silla in the years 1990 to 1994 with the ESO 50cm telescope are presented. Most of these data were already used in our individual studies of several binaries. Now all photometric measurements were reduced again with an advanced technique and are made available electronically. Our data for MY Ser have not yet been published; new light curve is given and solved. The result is that MY Ser is a contact binary, with very large fill-out parameter. Also a light curve and its solution for V1051 Cen are provided, and the problem of the period of V871 Cen is pointed out. Besides binaries (and the comparison and check stars) data for several stars in southern H II regions are included. Extinction and transformation coefficients are given.
- ID:
- ivo://CDS.VizieR/J/A+A/463/1061
- Title:
- UBV photometry of V379 Cep
- Short Name:
- J/A+A/463/1061
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Several binaries with masses anomalously small for their observed spectral types have been discussed in the astronomical literature and interpreted as the result of envelope ejection. V379 Cep is one of these objects. We obtained new series of electronic spectra and UBV photometry of V379 Cep and analysed them in an effort to check whether the conclusion about its anomalous masses may not be premature.
- ID:
- ivo://CDS.VizieR/J/A+A/387/240
- Title:
- UBV photometry of V899 Her
- Short Name:
- J/A+A/387/240
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The data file (v899her.dat) includes photometric observations of the eclipsing binary system V899 Herculis. The observations were carried out at the Ankara University Observatory in Johnson UBV filters by using an SSP-5 photometer head attached to the 30-cm Maksutov telescope of the Observatory. Observational standard errors are 0.020m, 0.016m, and 0.021m in U, B, and V filters, respectively. A total of 301, 305, and 298 data points are included for each UBV filters, respectively, in the Table.
- ID:
- ivo://CDS.VizieR/J/A+AS/125/407
- Title:
- UBV photometry of V839 Ophiuchi
- Short Name:
- J/A+AS/125/407
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A complete period variation analysis and new light curves of V839 Oph together with new ephemeris data are presented. The period variation was found to be dP/dt=3.1x10^-7d/yr. The period increament indicates that the conservative mass transfer rate from the less massive component to the more massive one is 6.5x10^-7M_sun_/yr. We fitted parabolic and we discuss the possible detection of sinusoidal curves to the (O-C) diagram and sinusoidal oscillations with period of about 20yr and semi-amplitude of 0.0065 day. A simultaneous solution of the B and V light curves was computed using the Wilson-Devinney synthetic light-curve code. The light curve solution indicates that the A-type W UMa-type system is in contact with a filling factor of ~39%.
- ID:
- ivo://CDS.VizieR/J/AJ/142/117
- Title:
- UBVrcIc differential photometry of V1853 Ori
- Short Name:
- J/AJ/142/117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present precision CCD light curves, a period study, photometrically derived standard magnitudes, and a five-color simultaneous Wilson code solution of the totally eclipsing, yet shallow amplitude (Av~0.4mag) eclipsing, binary V1853 Orionis. It is determined to be an extreme mass ratio, q=0.20, W-type W UMa overcontact binary. From our standard star observations, we find that the variable is a late-type F spectral-type dwarf, with a secondary component of about 0.24 solar masses (stellar type M5V). Its long eclipse duration (41 minutes) as compared to its period, 0.383-days, attests to the small relative size of the secondary. Furthermore, it has reached a Roche lobe fill-out of ~50% of its outer critical lobe as it approaches its final stages of binary star evolution, that of a fast spinning single star. Finally, a summary of about 25 extreme mass ratio solar-type binaries is given.
