- ID:
- ivo://CDS.VizieR/J/A+A/640/A128
- Title:
- Cygnus OB2 association NIR light curves
- Short Name:
- J/A+A/640/A128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a J, H, and K photometric variability survey of the central 0.78 square degrees of the young OB association Cygnus OB2. We used data observed with the Wide-Field CAMera at the United Kingdom Infrared Telescope in 2007 (spanning 217 days) to investigate the light curves of 5083 low mass candidate members in the association and explore the occurrence and main characteristics of their near-infrared variability. We identified 2529 stars (~50% of the sample) with significant variability with time-scales ranging from days to months. We classified the variable stars into the following three groups according to their light curve morphology: periodic variability (1697 stars), occultation variability (124 stars), and other types of variability (726 stars). We verified that the disk-bearing stars in our sample are significantly more variable in the near-infrared than diskless stars, with a steep increase in the disk-fraction among stars with higher variability amplitude. We investigated the trajectories described by variable stars in the color-space and measured slopes for 335 stars describing linear trajectories. Based on the trajectories in the color-space, we inferred that the sample analyzed is composed of a mix of young stars presenting variability due to hot and cold spots, extinction by circumstellar material, and changes in the disk emission in the near-infrared. We contemplated using the use of near- infrared variability to identify disk-bearing stars and verified that 53.4% of the known disk-bearing stars in our sample could have been identified as such based solely on their variability. We present 18 newly identified disk- bearing stars and 14 eclipsing binary candidates among CygOB2 lower-mass members.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/411/1585
- Title:
- CZ Lac multiperiodic Blazhko modulation
- Short Name:
- J/MNRAS/411/1585
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A thorough analysis of the multicolour CCD observations of the RRab-type variable, CZ Lacertae, is presented. The observations were carried out in two consecutive observing seasons in 2004 and 2005 within the framework of the Konkoly Blazhko Survey of bright, northern, short-period RRab variables.
203. Dahlmark variables
- ID:
- ivo://CDS.VizieR/II/238
- Title:
- Dahlmark variables
- Short Name:
- II/238
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Since 1967 32 fields in the Milky Way were observed for variable stars. * New variable stars in Cygnus (1982IBVS.2157....1D) [8/65] Survey of an area of 20{deg}x15{deg} centered at 20h50m, +45{deg} in Cygnus. This area has been followed photographically in two colours during the period 1967 to 1981. As a rule one observation per summer was obtained. * New variable stars in Cassiopeia (1986IBVS.2878....1D) [66/105] Survey in an area 20{deg}x15{deg} centered at 1h06m, +60{deg}01'. Seventeen plate pairs exposed in the period 1967 to 1981 were collected and treated in the same way as described in the previous report. These observations provide approximate B and V magnitudes. In addition, six exposures were obtained in the period August 8 to September 23, 1985 on Technical Pan film. * New variable stars in Cygnus, Lyra and Vulpecula (1993IBVS.3855....1D) [106/185] Area of 20{deg}x15{deg} centred at 19h46m +30{deg}. * New variable stars in Cygnus, Lacerta and Andromeda (1996IBVS.4329....1D) [186/220] Area of 20{deg}x15{deg} centered at 20h40m, +45{deg} (1950). * New variable stars in the northern Milky Way (1997IBVS.4458....1D) [221/280] Area of 20{deg}x15{deg} centered at 22h42m, +60{deg} (1950) * New variable stars in the northern Milky Way (1998IBVS.4642....1D) [281/315] Results of a variable-star search in the 20{deg}x15{deg} area centered at 20h18m, +60{deg} (1950). * New variable stars in Andromeda and Cassiopeia (1999IBVS.4734....1D [316/341] Results of a variable-star search in the 20{deg}x15{deg} area centered at 0h30m, +45{deg} (1950). * New variable stars in Lyra and Cygnus (2000IBVS.4898....1D) [342/366] Results of a variable-star search in the 20{deg}x15{deg} area centered at 19h00m/+45{deg} (1950). * New variable stars along the northern Milky way (2001IBVS.5181....1D) [367/420] Results of a variable-star search in the 20{deg}x15{deg} area centered at 21h22m/+{deg} (1950).
- ID:
- ivo://CDS.VizieR/J/A+AS/129/9
- Title:
- Delta Sct stars in Praesepe
- Short Name:
- J/A+AS/129/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photoelectric photometry of seven Delta Scuti stars in Praesepe was secured. Three of them were observed simultaneously at observatories located at different longitudes. Period analysis has been carried out for each star with different computing packages and the results compared to those in the literature. Their physical characteristics have been determined from the Stromgren photometry and theoretical and empirical calibrations.
- ID:
- ivo://CDS.VizieR/J/other/JAD/24.1
- Title:
- Delta Scuti Network photometric data. 4 CVn
- Short Name:
- J/other/JAD/24.1
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Nearly 1000 nights of high-precision photometry of the delta Scuti variable 4 CVn were obtained from 1966 to 2012. These data led to the discovery of 64+ frequencies of pulsation together with systematic changes in amplitudes and small period changes on a timescale of decades. This paper presents the previously unpublished data.
206. Delta Scuti stars
- ID:
- ivo://CDS.VizieR/J/A+AS/144/469
- Title:
- Delta Scuti stars
- Short Name:
- J/A+AS/144/469
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An extensive and up-dated list of {delta} Sct stars is presented here. More than 500 papers, published during the last few years, have been revised and 341 new variables have been added to our last list, six years ago. This catalogue is intended to be a comprehensive review on the observational characteristics of all the {delta} Sct stars known until now, including stars contained in earlier catalogues together with other new discovered variables, covering information published until January 2000. In summary, 636 variables, 1149 references and 182 individual notes are presented in this new list.
- ID:
- ivo://CDS.VizieR/J/PASP/106/1120
- Title:
- Delta Scuti variables. II. DY Her
- Short Name:
- J/PASP/106/1120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the second paper in a series on large-amplitude delta Scuti stars intended to determine Baade-Wesselink radii and luminosities with precision. The first paper (Wilson et al., 1993PASP..105..809W) discussed our method of analysis and its application to EH Librae; in this we discuss the observations and analysis of DY Herculis. Optical and infrared photometry and cross-correlated radial-velocity data have been obtained and analyzed. Fourier representations for the UBVRIJHK light curves and for the radial-velocity curves were used to derive a value for the minimum radius for each of 60 combinations of flux and color index. From these we adopt a mean value for the minimum radius of R_min_=2.77+/-0.20R_{sun}_. When combined with effective temperatures from Breger et al. (1978PASP...90..754B), we find a mean bolometric luminosity of <L_B_>=21.70L_{sun}_ and a mean absolute magnitude of <M_B_>=1.41. The radial excursion is 0.149R_{sun}_. We use the same procedure to improve our results for EH Librae, deriving R_min_ for each of 42 combinations of flux and color index, and obtain mean values of R_min_=2.62+/-0.19R_{sun}_, <L_B_>=24.56L_{sun}_ and <M_B_>=1.27.
- ID:
- ivo://CDS.VizieR/J/A+A/536/L9
- Title:
- Detections of transit variations in KOI 806
- Short Name:
- J/A+A/536/L9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the detection of transit timing variations (TTVs) well in excess of one hour in the Kepler multi-planet candidate system KOI 806. This system exhibits transits consistent with three separate planets - a Super-Earth, a Jupiter, and a Saturn - lying very nearly in a 1:2:5 resonance, respectively.
- ID:
- ivo://CDS.VizieR/J/ApJ/620/961
- Title:
- Diameters of Mira stars in JHK' bands
- Short Name:
- J/ApJ/620/961
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first spatially resolved observations of a sample of 23 Mira stars simultaneously measured in the near-infrared J, H, and K' bands. The technique used was optical long-baseline interferometry, and we present for each star visibility amplitude measurements as a function of wavelength. We also present characteristic sizes at each spectral band, obtained by fitting the measured visibilities to a simple uniform disk model. This approach reveals the general relation J diameter < H diameter < K' diameter.
- ID:
- ivo://CDS.VizieR/J/AcA/52/129
- Title:
- DIA OGLE2 candidate variable stars catalog
- Short Name:
- J/AcA/52/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first edition of a catalog of variable stars from OGLE-II Galactic bulge data covering 3 years: 1997-1999. Typically 200-300 I band data points are available in 49 fields between -11 and +11 degrees in galactic longitude, totaling roughly 11 square degrees in sky coverage. Photometry was obtained using the Difference Image Analysis (DIA) software and tied to the OGLE data base with the DoPhot package. The present version of the catalog comprises 221801 light curves. In this preliminary work the level of contamination by spurious detections is still about 10%. Parts of the catalog have only crude calibration, insufficient for distance determinations. The next, fully calibrated, edition will include the data collected in year 2000. The data is accessible via ftp, at ftp://bulge.princeton.edu/ogle/ogle2/bulge_dia_variables