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- ID:
- ivo://CDS.VizieR/J/MNRAS/428/3551
- Title:
- V2367 Cyg differential light curve
- Short Name:
- J/MNRAS/428/3551
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on a multi-site photometric campaign on the high-amplitude delta Scuti star V2367 Cyg in order to determine the pulsation modes. We also used high-dispersion spectroscopy to estimate the stellar parameters and projected rotational velocity. Time series multi colour photometry was obtained during a 98-d interval from five different sites. These data were used together with model atmospheres and non-adiabatic pulsation models to identify the spherical harmonic degree of the three independent frequencies of highest amplitude as well as the first two harmonics of the dominant mode. This was accomplished by matching the observed relative light amplitudes and phases in different wavebands with those computed by the models. In general, our results support the assumed mode identifications in a previous analysis of Kepler data.
22503. V1974 Cyg IUE spectroscopy
- ID:
- ivo://CDS.VizieR/J/A+A/420/571
- Title:
- V1974 Cyg IUE spectroscopy
- Short Name:
- J/A+A/420/571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a detailed analysis of the IUE archival high resolution spectra of the classical nova V1974 Cyg 1992. The main UV resonance lines show P Cygni profiles in the first days, which change into symmetric pure emission lines, and then slowly become fainter and narrower. Lines of higher ionization species reach their peak luminosity later than those of low ionization.
- ID:
- ivo://CDS.VizieR/J/PAZh/41/665
- Title:
- V1016 Cyg light curves and spectroscopy
- Short Name:
- J/PAZh/41/665
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As a result of the next cycle of our long-term monitoring, we present our UBV JHKLM photometry for the symbiotic nova V1016 Cyg in 2008-2014. The star continued to systematically fade and redden in UBV: over this period, the brightness declined by 0.1m in V and by 0.2m in B and U ,the B-V color index increased by 0.1m, and U-B barely changed. On the color-color (U-B, B-V) diagram, the star moved approximately horizontally rightward with a slight bluing in U-B starting from 2000. Our JHKLM photometry has shown a decline in the mean infrared (IR) brightness and a rise in the mean IR color indices after 2004 due to an increase in the optical depth of the dust envelope. The brightness decline and reddening of the Mira in the near infrared reached their extreme values over the entire period of the system's observations by the end of 2014. The pulsation period of the Mira is determined with confidence: P=465+/-5-days. The distance to the Mira, D=2.92+/-0.16kpc, ant its parameters, the radius R*=(470+/-50)R_{sun}_ and luminosity L*=(9200+/=1900)L_{sun}_, have been estimated from the observations of V1016 Cyg at its maximum J brightness and at its minimum J-H color index. The temperature of the star during its pulsations varied within the range T* =2100-2700K. We have estimated the parameters of the dust envelope near its maximum (in 2004) and minimum (in 2012-2014) IR brightness. The mass of the dust envelope almost doubled in ten years, with the rate of dust supply being {Delta}Md~10^-7^M_{sun}_/yr. Using a low-resolution spectrograph, we performed absolute spectrophotometry for V1016 Cyg in 1995-2013 in the range {lambda}4340-7130{AA}. We have shown that almost all absolute fluxes in lines and in continuum at {lambda}4400{AA} decrease monotonically after 2000, while the relative intensities of [OIII], [FeVII], and [CaVII] lines increase after the minimum that probably occurred in the 1990s. The significant (approximately by a factor of 10 from 1995 to 2013) decrease of the flux in the Raman OVI {lambda}6825 line reflects a change of conditions in the formation zone of this line due to the absorption of some OVI {lambda}1032 photons in the newly forming dust envelope of the cool component.
22505. V2492 Cyg light variations
- ID:
- ivo://CDS.VizieR/J/A+A/551/A62
- Title:
- V2492 Cyg light variations
- Short Name:
- J/A+A/551/A62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- V2492 Cyg is a young eruptive star that went into outburst in 2010. The near-infrared color changes observed since the outburst peak suggest that the source belongs to a newly defined sub-class of young eruptive stars, where time-dependent accretion and variable line-of-sight extinction play a combined role in the flux changes. In order to learn about the origin of the light variations and to explore the circumstellar and interstellar environment of V2492 Cyg, we monitored the source at ten different wavelengths, between 0.55um and 2.2um from the ground and between 3.6um and 160um from space. We analyze the light curves and study the color-color diagrams via comparison with the standard reddening path. We examine the structure of the molecular cloud hosting V2492 Cyg by computing temperature and optical depth maps from the far-infrared data.
- ID:
- ivo://CDS.VizieR/J/PAZh/42/831
- Title:
- V1027 Cygni UBV and JHKLM photometry
- Short Name:
- J/PAZh/42/831
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our UBV and JHKLM photometry for the semiregular pulsating variable V1027 Cyg, a supergiant with an infrared excess, over the period from 1997 to 2015 (UBV) and in 2009-2015 (JHKLM). Together with the new data, we analyze the photometric observations of V1027 Cyg that we have obtained and published previously. Our search for a periodicity in the UBV brightness variations has led to several periods from P=212d to 320d in different time intervals. We have found the period P=237d based on our infrared photometry. The variability amplitude, the lightcurve shape, and the magnitude of V1027 Cyg at maximum light change noticeably from cycle to cycle.
22507. V407 Cyg spectral variations
- ID:
- ivo://CDS.VizieR/J/A+A/600/A96
- Title:
- V407 Cyg spectral variations
- Short Name:
- J/A+A/600/A96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The outburst of the symbiotic recurrent nova V407 Cyg in 2010 has been studied by numerous authors. On the other hand, its spectral variations in the quiescent stage have not been well studied yet. This paper is probably the first report for the relation between the pulsation of the secondary Mira variable and the temperature of the primary hot component for V407 Cyg. The spectral variation in the post-outburst stage has been monitored to study the properties of this object. In the course of this work, we found some unexpected spectral variations around the light maximum of the secondary Mira variable in 2012. The relation between the mass transfer in the binary system and the pulsation of the secondary Mira variable is studied. High- and low-resolution optical spectra obtained at the Astronomical Observatories at Asiago were used. The photometric data depend on the database of the VSNET.
- ID:
- ivo://CDS.VizieR/J/AZh/85/409
- Title:
- V1357 Cyg spectroscopic monitoring in 2002-04
- Short Name:
- J/AZh/85/409
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of Cyg X-1 = HDE 226868/V1357 Cyg optical spectral monitoring in 2002-2004 are discussed. Spectral observations were carried out on Peak Terskol Observatory (Kabardino-Balkaria, Russia, resolution R=45000 and 13000) and Bohyunsan Optical Astronomy Observatory (BOAO, Korea, R=30000, 44000). Each spectrum covers the main part of optical spectral range. During 33 observational nights 75 echelle spectra were obtained in the times of the "soft" and "hard" states of Cyg X-1. The X-ray influence on spectral line profiles was studied. The RXTE/ASM data were used for this purpose. The X-ray flare resulted in strong variations of Halpha and HeII4686{AA} emission component profiles during night. This behaviour we connect with variations of ionization structure of matter in the system. Line profile variations with the orbital phase were observed. The spectral atlas for Cyg X-1 was constructed. The contented line identification was done. There were revealed 172 lines and blends which belong to 12 chemical elements: H, He, C, N, O, Ne, Mg, Al, Si, S, Fe, Zn. The HDE 226868 spectral classification as ON star was confirmed.
- ID:
- ivo://CDS.VizieR/J/PAZh/41/148
- Title:
- V1329 Cyg UBV light curves and spectrum
- Short Name:
- J/PAZh/41/148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The photoelectric UBV observations of the peculiar symbiotic star V1329 Cyg performed at the Crimean Station of the SAI-MSU during 245 nights over the period 2003-2014 are presented. The star's light curves since 1973 from the Crimean observations are shown. The brightness decline after its outburst over the last 40 years was 0.8m-1.0m. The phase color curves at phases 0.2 and 0.8 have maxima. Their qualitative interpretation in terms of the model of interacting winds in symbiotic binary star systems is proposed. The orbital period of the binary system has been redetermined. The spectroscopic observations at the 125-cm telescope of the Crimean Station from 1994 to 2014 have confirmed the change in the system's emission spectrum with orbital phase.
22510. V729 Cyg UBVRI light curves
- ID:
- ivo://CDS.VizieR/J/other/NewA/31.32
- Title:
- V729 Cyg UBVRI light curves
- Short Name:
- J/other/NewA/31.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multicolor photometry of the massive interacting close binary system V729 Cyg. The light variations of V729 Cyg were observed in the Bessel U, B, V, R and I bands over 65 nights between August 2010 and October 2011.
