- ID:
- ivo://CDS.VizieR/J/PASP/130/C4201
- Title:
- BVR light curves of UZ Leo
- Short Name:
- J/PASP/130/C4201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New CCD photometric observations of UZ Leo were obtained between 2012 February and 2013 April, and on 2017 February. Its physical properties were derived from detailed analyses of our light curves and existing radial velocities. The results indicate that this system is a totally eclipsing A-subtype overcontact binary with both a high fill-out factor of 76% and a third light source contributing 12% light in the B bandpass, 10% in V, and 7% in R. The light residuals between observations and theoretical models are satisfactorily fitted by adopting a magnetic cool spot on the more massive primary star. Including our 12 measurements, a total of 172 eclipse times were used for ephemeris computations. We found that the orbital period of UZ Leo has varied due to a periodic oscillation superposed on an upward parabolic variation. The observed period increase at a rate of +3.49x10^-7^day/yr can be plausibly explained by some combination of non-conservative mass transfer from the secondary to the primary component and angular momentum loss due to magnetic braking. The period and semi-amplitude of the oscillation are about 139 years and 0.0225 days, respectively, which is interpreted as a light-time effect due to a third component with a mass of M_3_sini_3_=0.30M_\{sun}_. Because the third lights of 7%-12% indicate that the circumbinary object is very overluminous for its mass, it would possibly match a white dwarf, rather than an M-type main sequence.
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- ID:
- ivo://CDS.VizieR/J/other/NewA/17.46
- Title:
- BVR light curves of V1191 Cyg
- Short Name:
- J/other/NewA/17.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of photometric and spectroscopic variation, and orbital period study of the late-type contact binary system V1191 Cyg. The system is found to be a contact binary system having strange configuration with very small mass ratio and short orbital period comparing with the other members of the same group. We determined a new set of stellar physical parameters for hot and cooler companion as M_h_=0.13(1)M_{sun}_, M_c_=1.29(8)M_{sun}_, R_h_=0.52(15)R_{sun}_, R_c_=1.31(18)R_{sun}_, L_h_=0.46(25)L_{sun}_, L_c_=2.71(80)L_{sun}_, and the separation between the components a=2.20(8)R_{sun}_ from the simultaneous solution of the light and radial velocity curves. Analyses of the mid-eclipses time of the system indicate a period increase of dP/dt=1.3(1)x10^-6^days/yr that can be interpreted in terms of the high mass transfer dM/dt=2.0(4)x10^-7^M_{sun}_/yr from the less massive component to the more massive one.
- ID:
- ivo://CDS.VizieR/J/AJ/149/62
- Title:
- BVR light curves of V508 Oph
- Short Name:
- J/AJ/149/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, new CCD photometric observations of V508 Oph obtained in 2009 and 2010 at the Xinglong Observatory are presented. From the new observations, six new times of minimum light were derived. The light curves were analyzed by using the 2003 version of the Wilson-Devinney program. It is found that the asymmetric light curves can be modeled by a hot spot on the secondary component. The degree of overcontact is 15.4%, implying that the system is a shallow-contact binary. Combining the new times of minimum light with the photoelectric and CCD data compiled from the database, we investigate its orbital period. The results show that the orbital period may be undergoing multiple changes: a long-term decrease at a rate of dP/dt=-(1.502+/-0.063)x10^-7^days/year, and a small periodic variation with a period of 24.27(+/-0.34) years. Since V508 Oph is an overcontact system and both components are late-type stars, we discuss the possible connection between the mass transfer, magnetic activity, the third body, and the orbital period changes.
- ID:
- ivo://CDS.VizieR/J/PAZh/23/341
- Title:
- BVR observations of SS 433
- Short Name:
- J/PAZh/23/341
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photoelectric BVR photometry of SS 433 performed between 1988 and 1990 at Mt. Maidanak is presented.
- ID:
- ivo://CDS.VizieR/J/AJ/102/395
- Title:
- BVR photoelectric sequences in the PSS
- Short Name:
- J/AJ/102/395
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- BVR photoelectric photometry and positions are reported for 437 stars in 49 Palomar Sky Survey fields. A relation is derived between the Johnson BVR photometry and the E and O photographic magnitudes on the Palomar plates. The BVR photometry, the E and O magnitudes, and the 1950 positions are presented in the accompanying catalog.
- ID:
- ivo://CDS.VizieR/J/A+A/454/179
- Title:
- BVR phot. of Basel 11b, King 14, Czernik 43
- Short Name:
- J/A+A/454/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To progress in galactic studies based on open clusters, e.g. cluster formation rate or kinematical properties, one needs to improve the number of open clusters observed. However, only half of the 1700 known galactic open clusters have been properly observed so far, making any statistical investigation insignificant, especially at larger distances from the Sun. We study marginally investigated or neglected open clusters with Bessell CCD BVR photometry, whose data were used to fit isochrones to the individual color-magnitude diagrams. We examined the galactic clusters Basel 11b, King 14 and Czernik 43, the last being observed for the first time to this extent. As well as a careful comparison to available photometry, their parameters such as age, interstellar reddening, distance and apparent diameter were determined. The obtained cluster properties were verified by near infrared 2MASS data. The three investigated intermediate age clusters are all located in the galactic disk with distances between 1.8 and 3.0kpc from the Sun.
- ID:
- ivo://CDS.VizieR/J/A+A/382/60
- Title:
- BVR photometry in Abell 1689
- Short Name:
- J/A+A/382/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At a redshift of 0.18, Abell 1689 is so far the most distant cluster of galaxies for which substantial mid-infrared (MIR) data have been published. Its mapping with the ISOCAM camera onboard the ISO satellite allowed the detection of 30 cluster members at 6.75{mu}m (LW2 filter) and 16 cluster members at 15{mu}m (LW3 filter) within a clustercentric radius of 0.5Mpc (Fadda et al., 2000A&A...361..827F, Paper I). We present here the follow-up optical photometric and spectroscopic observations which were used to study the individual properties of the galaxy members of A1689. We confirm the high fraction of blue galaxies initially reported in this rich cluster by Butcher & Oemler (1984ApJ...285..426B), that was challenged by some subsequent studies. We discuss the spectral and morphological properties of all cluster members in our spectroscopic sample, and of the MIR-detected galaxies in particular.
- ID:
- ivo://CDS.VizieR/J/A+A/436/117
- Title:
- BVR photometry in N214C
- Short Name:
- J/A+A/436/117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the Large Magellanic Cloud HII region N 214C using imaging and spectroscopy obtained at the ESO New Technology Telescope. On the basis of the highest resolution images so far obtained of the OB association LH 110, we show that the main exciting source of the HII region, Sk -71 51, is in fact a tight cluster of massive stars consisting of at least 6 components in an area ~4" wide. Spectroscopic observations allow us to revise the spectral type of the main component (#17) to O2V((f*))+OB, a very rare, hot type. We also classify several other stars associated with N 214C and study the extinction and excitation characteristics of the HII region. Moreover, we obtain BVR photometry and astrometry of 2365 stars and from the corresponding color-magnitude diagram study the stellar content of N 214C and the surrounding LH 110. Furthermore, we discover a striking compact blob of ionized gas in the outer northern part of N 214C. A spherical structure of ~5", in radius (~1.3pc), it is split into two lobes by absorbing dust running diametrically through its center. We discuss the possible nature of this object.
- ID:
- ivo://CDS.VizieR/J/other/AISAO/32.31
- Title:
- BVr photometry in SA68, SA 5 and M 82
- Short Name:
- J/other/AISAO/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A description of the photometry and spectroscopy of the objects of the fields SA 68 (00h14m51.03s +15deg36'19.1"), M 82 (9h53m28.33s +69deg52'12.7") and SA 57 (13h06m03.69s +29deg36'31.8") is given. Photometric samples of the objects are complete to B=21.75m for the field SA 68, to B=22.25m for the field M 82. and to B=23m for the field SA 57. Spectroscopy is completed up to 64 % for the field SA 68, to 63% for the field M 82, and to 56% for the field SA 57. Photometric and spectroscopic data are gathered into catalogues.
- ID:
- ivo://CDS.VizieR/J/A+AS/128/67
- Title:
- BVR photometry of Abell 85
- Short Name:
- J/A+AS/128/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two catalogues of galaxies in the direction of the rich cluster ABCG 85. The first one includes 4232 galaxies located in a region +/-1{deg} from the cluster centre. It has been obtained from a list of more than 25000 galaxy candidates detected by scanning a Schmidt photographic plate taken in the B_J_ band. Positions are very accurate in this catalogue but magnitudes are not. This led us to perform CCD imaging observations in the V and R bands to calibrate these photographic magnitudes. A second catalogue (805 galaxies) gives a list of galaxies with CCD magnitudes in the V and R bands for a much smaller region in the centre of the cluster. These two catalogues will be combined with a redshift catalogue of 509 galaxies by Durret et al. (1997, subm.) to investigate the cluster properties at optical wavelengths Durret et al. (1997, subm.), as a complement to our previous X-ray studies (Pislar et al., 1997A&A...322...53P; Lima-Neto et al., 1997A&A...327...81L).
