- ID:
- ivo://CDS.VizieR/J/AcA/48/35
- Title:
- All Sky Automated Survey variable stars
- Short Name:
- J/AcA/48/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of the first two months of observations using the All Sky Survey prototype camera are presented. More than 45000 stars in 24 Selected Fields covering 140 square degrees were monitored a few times per night resulting in the I-band catalog containing 10^7^ individual measurements. Period search revealed 126 variable stars brighter than 13mag with periods less than 20d. Only 30 of them are known variable stars included in the General Catalogue of Variable Stars (<II/214>). The other 90 objects are newly detected variable stars - mainly eclipsing binaries (75%) and pulsating stars (17%). We estimate that completeness of the current catalogs of variable stars is smaller than 50% already for the stars brighter than 9mag. The catalog is accessible over the WWW: http://www.astrouw.edu.pl/~gp/asas/asas.html
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- ID:
- ivo://CDS.VizieR/I/280B
- Title:
- All-Sky Compiled Catalogue of 2.5 million stars
- Short Name:
- I/280B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The All-Sky Compiled Catalogue of 2501313 stars (ASCC-2.5) with the limiting magnitude V=12-14 is a result of a merging of star lists from present day large high-precision catalogues from space (Hipparcos- Tycho family catalogues: Hipparcos main catalogue including Multiple System Annex [I/239], Tycho-1 [I/239], Tycho-2 [I/259], ACT-RC [I/246], TRC [I/250]) and ground-based (PPM-N [I/146], PPM-S [I/193], PPM-add [I/208], CMC11 [I/256]) observations and reduction to standard systems of corresponding stellar data. The data from the Tycho-2 Spectral Type Catalog [III/231], and the 2MASS All-Sky Catalog of Point Sources [II/246] are added. The basic stellar data presented in the ASCC-2.5 are the equatorial coordinates (J2000, epoch 1991.25), proper motions in the Hipparcos system, B and/or V stellar magnitudes in the Johnson system. Additionally, for some stars we give trigonometric parallaxes, spectral classes in the MK or HD system, multiplicity and variability flags, Hipparcos, Tycho-2, HD, DM designations. Equatorial coordinates and their standard errors were taken from the source catalogues in accordance with the priority: Hipparcos [I/239/hip_main], Tycho-2 [I/259], Tycho-1 [I/239/tyc_main], CMC11 [I/256], PPM [I/146,I/193,I/208]. Proper motions from the source catalogues were compared with Hipparcos data.The compiled proper motions in the Hipparcos system and their standard errors were computed as the weighted means. The weights were set in accordance with the proper motion errors listed for individual stars in the source catalogues. Trigonometric parallaxes are taken from the Hipparcos and Tycho-1 catalogues. Stellar B, V magnitudes were determined on the basis of the ground- based photometric data taken from CMC11, Hipparcos, as well as space BT, VT from Tycho-1, Tycho-2. Magnitudes from the PPM catalogue were used if no other photometric data were available. Tycho data were transformed to the Johnson system via: V = VT - 0.09 (B-V)T + dV, (B-V) = 0.850 (B-V)T + d(B-V), i.e. using the recommendations from the Introduction to the Tycho catalogue and including additional corrections dV and d(B-V). These additional corrections were determined by comparison with ground-based data in the Johnson system. These corrections depend non-linearly on colour and reach 0.02 and 0.04 mag, respectively. Infrared stellar magnitudes J, H, K_s_ and their errors were copied from the 2MASS catalogue. Spectral classes in the MK or HD systems were taken from Hipparcos, CMC11, PPM, and Tycho-2 Spectral Type catalogues. Multiplicity and variability flags were taken from Tycho-1, Tycho-2, Hipparcos, CMC11, and PPM catalogues. The 1st version of the ASCC-2.5 contained some errors in the zones -1 to +1 degree which have been corrected (see details in the "History" section below). The 2nd version included a new file (ccadd.dat) containing the previously missing stars (including components of multiple systems). Note that the ASCC numbers did not change between the two versions, but additional numbers (2600001 to 2603318) were assigned. In the present 3rd version of the ASCC-2.5 the stars from file ccadd.dat are inserted in the basic files in accordance with their coordinates. Stars in the ASCC-2.5 are divided into 30 files ordered by declination (North and South polar caps and 28 bands of 5 degrees width), then sorted in order of right ascension within each file.
- ID:
- ivo://CDS.VizieR/J/A+A/504/959
- Title:
- Amplitudes of single-mode Cepheids
- Short Name:
- J/A+A/504/959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The dependence of amplitude on the pulsation period differs from other Cepheid-related relationships. We attempt to revise the period-amplitude (P-A) relationship of Galactic Cepheids based on multi-colour photometric and radial velocity data. Reliable P-A graphs for Galactic Cepheids constructed for the U, B, V, Rc, and Ic photometric bands and pulsational radial velocity variations facilitate investigations of previously poorly studied interrelations between observable amplitudes. The effects of both binarity and metallicity on the observed amplitude, and the dichotomy between short- and long-period Cepheids can both be studied. A homogeneous data set was created that contains basic physical and phenomenological properties of 369 Galactic Cepheids. Pulsation periods were revised and amplitudes were determined by the Fourier method. P-A graphs were constructed and an upper envelope to the data points was determined in each graph. Correlations between various amplitudes and amplitude-related parameters were searched for, using Cepheids without known companions.
- ID:
- ivo://CDS.VizieR/J/A+A/328/235
- Title:
- AN Lyn light maxima
- Short Name:
- J/A+A/328/235
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New uvby data collected of AN Lyn together with the reanalysis of old data establish that this star is a multiperiodic pulsator. Three independent frequencies ({nu}_1_=10.1756, {nu}_2_=18.1309 and {nu}_3_=9.5598c/d) and some interactions between them are found to be present in the light curve. Changes in amplitude with a large time scale are confirmed for the main frequency. Moreover, changes in amplitude are also present for the secondary frequencies, especially for {nu}_3_. After subtraction of the secondary frequencies from the light curves, the classical O-C method has been used to analyse the behaviour of the main period. A comparison is made between AN Lyn and the other two known {delta} Sct stars with atypical light curves, i.e., V1719 Cyg and V798 Cyg. New uvby data have been also collected for V1719 Cyg and the O-C method has been used to analyse the behaviour of the main period. It is found that the main pulsation of this star can be well described by means of a linear ephemeris with a period of P=0.26729700d over the last eighteen years. Finally, analysis of the different data sets available in the literature do not reveal significative changes in the amplitude of the main frequency of V1719 Cyg.
- ID:
- ivo://CDS.VizieR/J/AZh/84/695
- Title:
- An SX Phoenicis Variable light curve
- Short Name:
- J/AZh/84/695
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present investigation of V=17mag star, which appears to be SX Phe type variable. Observations at 1.8 and 1.0 meter telescopes of Boyhunsan and Mount Lemon observatories permit us to improve the light elements and to investigate the power spectrum. We applied a Fourier decomposition to the data in order to determine the component frequencies of the synthetic light curve, and five components including a pair of closely separated components of f_1_=24.6539 and f_2_=24.8173 c/d were identified. We proposed that one of these two components corresponds to a non-radial oscillation mode. Other observed frequencies are the combinations of the first two. Metallicity of the star was estimated to be [Fe/H]<-2. We also found that one of the faint variable stars, No. 14, in the field is RRc type pulsator.
- ID:
- ivo://CDS.VizieR/J/other/JAD/20.4
- Title:
- 180 APASS variable stars in Aquarius
- Short Name:
- J/other/JAD/20.4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During a search for RR Lyr variable stars candidate members of the Aquarius stream, which led to the discovery of 71 such objects, we also discovered an additional 180 variables which are presented in this paper. Of them, 141 were previously reported as variables and 39 are brand new. For all 180 objects, we provide: our epoch photometry, accurate positions, mean magnitude and amplitude of variation in Landolt B,V and Sloan g, r, i bands, cross-identification with WISE, 2MASS and GALEX surveys, accurate BVRCICgri photometric sequences and finding charts identifying the variable and the stars of the photometric sequence provided to support follow-up observations. We carried out a Fourier search on all 39 new variables and found periods for 11 of them.
- ID:
- ivo://CDS.VizieR/J/A+A/450/873
- Title:
- Araucaria: NGC 6822 bright variables VI phot.
- Short Name:
- J/A+A/450/873
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed a search for variable stars in the dwarf irregular galaxy NGC 6822 using wide-field multi-epoch VI photometry down to a limiting magnitude of ~22. A part from the Cepheid variables in this galaxy already reported in an earlier paper by Pietrzynski et al. (2004AJ....128.2815P), we have found 1019 "non-periodic" variable stars, 50 periodically variable stars with periods ranging from 0.12 to 66 days and 146 probably periodic variables. Twelve of these stars are eclipsing binaries and fifteen are likely new, low-amplitude Cepheids.
- ID:
- ivo://CDS.VizieR/J/AJ/140/1475
- Title:
- ARAUCARIA: NGC 7793 Cepheids
- Short Name:
- J/AJ/140/1475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the first time, we have detected Cepheid variables in the Sculptor Group spiral galaxy NGC 7793. From wide-field images obtained in the optical V and I bands on 56 nights in 2003-2005, we have discovered 17 long-period (24-62 days) Cepheids whose periods and mean magnitudes define tight period-luminosity relations. We use the (V-I) Wesenheit index to determine a reddening-free true distance modulus to NGC 7793 of 27.68+/-0.05mag (internal error) +/-0.08mag (systematic error).
- ID:
- ivo://CDS.VizieR/J/ApJ/648/375
- Title:
- Araucaria: NGC 3109 Cepheids JK phot.
- Short Name:
- J/ApJ/648/375
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared J- and K-band photometry of 77 Cepheid variables in the Local Group galaxy NGC 3109. Combining our data with the previously published optical V- and I-band photometry of Cepheids in this galaxy, we derive an accurate distance and interstellar reddening toward NGC 3109.
- ID:
- ivo://CDS.VizieR/J/ApJ/648/366
- Title:
- Araucaria: NGC 3109 Cepheids VI phot.
- Short Name:
- J/ApJ/648/366
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained mosaic images of NGC 3109 in the V and I bands on 74 nights, spanning approximately 1yr. From these data, we have conducted an extensive search for Cepheid variables over the entire field of the galaxy, resulting in the discovery of 113 variables with periods ranging from 3.4 to 31.4days. In this sample, 76 Cepheids, including many long-period variables, were not known before. For the previously known 45 Cepheids in this galaxy, our data proved that reported periods were wrong for 14 objects; for nearly all other previously known Cepheid variables, we were able to significantly improve on the periods.