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- ID:
- ivo://CDS.VizieR/J/ApJS/238/4
- Title:
- Updated cat. of Algol-type binaries from CSSs
- Short Name:
- J/ApJS/238/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an updated catalog of 4680 northern eclipsing binaries (EBs) with Algol-type light-curve (LC) morphology (i.e., with well-defined beginnings and ends of primary and secondary eclipses), using data from the Catalina Sky Surveys. Our work includes revised period determinations, phenomenological parameters of the LCs, and system morphology classifications based on machine-learning techniques. While most of the new periods are in excellent agreement with those provided in the original Catalina catalogs, improved values are now available for ~10% of the stars. A total of 3456 EBs were classified as detached and 449 were classified as semi-detached, while 145 could not be classified unambiguously into either subtype. The majority of the SD systems seem to be comprised of short-period Algols. By applying color criteria, we searched for K- and M-type dwarfs in these data, and present a subsample of 609 EB candidates for further investigation. We report 119 EBs (2.5% of the total sample) that show maximum quadrature light variations over long timescales, with periods bracketing the range 4.5-18 years and a fractional luminosity variance range of 0.04-0.13. We discuss possible causes for this, making use of models of variable starspot activity in our interpretation of the results.
- ID:
- ivo://CDS.VizieR/V/97
- Title:
- Updated 3rd Cat Variable Stars in Globular Clusters
- Short Name:
- V/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This Catalogue is an update to Helen Sawyer Hogg's Third Catalogue on Variable Stars in Globular Clusters (1973, David Dunlap Observatory Publications, Volume 3, Number 6). This update is based mainly on reference cards prepared by Helen Sawyer Hogg from articles published in the literature in the period 1973 to 1988. There are also some references entered from more recent literature and we are attempting to bring the catalogue up to date. Not all known globular clusters have been included, as the literature search is not at this point complete.
1434. U Sgr BV light curves
- ID:
- ivo://CDS.VizieR/J/PAZh/40/221
- Title:
- U Sgr BV light curves
- Short Name:
- J/PAZh/40/221
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the classical Cepheid U Sgr, we have constructed an O-C diagram spanning a time interval of 144 years. The O-C diagram has the shape of a parabola, which has made it possible to determine for the first time the quadratic light elements and to calculate the rate of evolutionary increase in the period, dP/dt=0.39(+/-0.10)s/yr, in agreement with the results of theoretical calculations for the third crossing of the instability strip. The available data reduced by the Eddington-Plakidis method reveal small random period fluctuations that do not distort the evolutionary trend in the O-C residuals.
- ID:
- ivo://CDS.VizieR/J/ApJ/525/420
- Title:
- UV and optical line variations in {epsilon} Persei
- Short Name:
- J/ApJ/525/420
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The rapid variable star, {epsilon} Per (B0.5 IV-III), displays the largest amplitude profile fluctuations known among the growing number of massive, spectrum-variable stars. Here we present an analysis of a continuous 5 day run of IUE UV spectroscopy, and we show for the first time that the systematic, blue-to-red moving patterns observed in high-quality optical spectra are also present in the UV photospheric lines. We present cross-correlation functions of the individual spectra with that of a narrow-lined standard that produce a high signal-to-noise ratio representation of the blue-to-red moving bump patterns found in individual lines. We then use time series analysis methods to determine the periodic components of the profile variations (after reregistering the spectra to correct for binary motion). There are at least six periods present (ranging from 8.46 to 2.27 hr), and most of these signals are also found in optical line variations observed in 1986 (although the relative amplitudes have changed significantly). Furthermore, analysis of a shorter time series of IUE spectra from 1984 shows that similar periods were present then. We also present H{alpha} and He I 6678 profiles obtained with the Georgia State University Multi-Telescope Telescope, which were made simultaneously with IUE, and we show that the profile variations are essentially identical in the UV and optical ranges.
- ID:
- ivo://CDS.VizieR/J/A+AS/103/183
- Title:
- UVBRI photometry of FK Com
- Short Name:
- J/A+AS/103/183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+AS/101/421
- Title:
- uvby-beta photometry of GP And
- Short Name:
- J/A+AS/101/421
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+AS/100/571
- Title:
- uvby-beta photometry of SX Phe stars
- Short Name:
- J/A+AS/100/571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+A/304/415
- Title:
- uvby-Hbeta photometry of Eta Car 1992-94
- Short Name:
- J/A+A/304/415
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present and analyze two seasons of intense photometric monitoring in the Stroemgren uvbyH{beta} system of {eta} Carinae (October 1992-August 1994). The luminous blue variable (LBV) in the core did not show much S Dor activity, i.e. it was in a relatively quiescent stage. This situation was very favourable for studying its optical micro variations. It appears that the central LBV pulsates (presumably in a non-radial mode) like other massive evolved stars, the {alpha} Cyg variables. The quasi-period is 58.56d. The linear ephemeris is: JD_max_=2448875.0 +58.56 E. Support was found for the existence of the presumed periodicity of 52.4d of the so-called "dimples", shallow dips in the light curve which only last for a few days. The cause may be the eclipse of a small companion or of a hot spot in an accretion disk. The H{beta} index became bluer by ~0.07mag during the last 11/2 years and shows an oscillation in anti-phase with the 58.56d pulsation, suggesting that the HII region(s) responsible for the hydrogen line emission has a relatively high luminosity. This is another reason to suppose that a second luminous source, perhaps a luminous disk (with a hot spot), may be present in the {eta} Car system.
- ID:
- ivo://CDS.VizieR/J/A+A/372/588
- Title:
- uvby light curves of V2154 Cyg
- Short Name:
- J/A+A/372/588
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 1 contents 852 simultaneous measurements collected in each of the four uvby colours of the Stromgren photometric system for the eclipsing binary system V2154 Cyg. The data are magnitude differences (Du,Dv,Db,Dy,D(b-y),Dm1,Dc1) of the variable star minus comparison star in the standard system versus Heliocentric Julian Day. The comparison star is HD 204626. The observations were carried out (by E. Rodriguez, J.M. Garcia, S. Martin and A. Claret) through the year 1998 using the 0.90m telescope at Sierra Nevada Observatory, Spain. This telescope is equipped with a six-channel uvby-Hbeta spectrograph photometer for simultaneous measurements in uvby or in the narrow and wide Hbeta channels, respectively.