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- ID:
- ivo://CDS.VizieR/J/A+AS/93/383
- Title:
- UBVRIJHKL photometry of symbiotic stars
- Short Name:
- J/A+AS/93/383
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+AS/102/343
- Title:
- UBVRI polarization of RS CVn-type binaries
- Short Name:
- J/A+AS/102/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/ApJS/171/249
- Title:
- Ultraviolet Spectral Atlas of VV Cephei
- Short Name:
- J/ApJS/171/249
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first observations of the ultraviolet spectrum of the binary system VV Cep (M2Iab + B?) during total eclipse have been made with the HST. A rich emission-line spectrum is seen, with over two thousand emission features present. Shortward of 1600{AA}, a weak continuum presumably due to Rayleigh scattering of the hot component is present, strengthening markedly shortward of 1500{AA}. The continuum of the M supergiant becomes apparent longward of 2650{AA}. Numerous circumstellar and interstellar absorption features are also seen. We present an atlas of the spectrum from 1300-3160{AA} as observed near midtotality and at two epochs closer to egress, when gas surrounding the hot component has begun to emerge from eclipse and the flux on the short-wavelength edges of many emission lines has increased. This atlas has been annotated with line identifications. Circumstellar and interstellar absorption features seen out of eclipse remain in absorption during totality and are also annotated on the atlas. Well over 90% of the emission features have plausible identifications, but there are many blends. Only a few hundred features appear to be free enough from blending for useful measurement of the peak flux in the line. We present a list of these unblended features.
- ID:
- ivo://CDS.VizieR/J/A+A/309/521
- Title:
- 55 UMa spectroscopic orbit
- Short Name:
- J/A+A/309/521
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first investigation of the known triple system 55 UMa (2.55d binary in a ~1870-d orbit with the third star) based on electronic spectra led to several new findings about the system: (1) Discovery of spectral lines of the tertiary and an unambiguous detection of the lines of the secondary. Spectra of both primary and tertiary are of the same strength and correspond to spectral class A0V. The secondary spectrum is about twice fainter in the visual region and belongs probably also to spectral class A. (2) First self-consistent orbital solution describing close and wide orbit and the detection of apsidal motion for the close pair. The orbital period of the close pair was improved to (2.5538380+/-0.0000046d) and basic physical elements for all three stars and the system were estimated. The orbital solution also gives the period of apsidal motion of the close pair of (450+/-60)yr and leads to a good agreement with the published speckle-interferometric orbit for the distant companion if the longitude of periastron passage is increased by 180deg.
- 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+A/415/273
- Title:
- UVBRI photometry and spectroscopy of AG Dra
- Short Name:
- J/A+A/415/273
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric UBVri observations of the symbiotic star AG Dra in Piwnice Observatory, Torun, Poland, are presented in tables 2 and 3. The 60cm telescope and a single-channel photoelectric photometer have been used. Table 2 lists observations with the EMI9558B photomultiplier tube from March 1996 to September 1999. Table 3 lists observations with the cooled C31034 photomultiplier tube from October 2001 to May 2003. Table 4 lists equivalent widths (EW) of the four emission lines in the spectrum of AG Dra: The Raman scattered line at 6825{AA}, H{alpha}, H{beta} and He II 4686{AA}. The spectroscopic observations have been performed in Tartu Observatory, Estonia, using the 1.5m telescope and a Cassegrain spectrograph. The time interval extends from September 1997 to March 2003.
- ID:
- ivo://CDS.VizieR/J/A+A/472/241
- Title:
- UV Flux distributions of gamma Dor stars
- Short Name:
- J/A+A/472/241
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It seems that the recently identified class of pulsating stars, the gamma Dor type-variables, includes objects with different metal abundances and a large percentage of binaries. We looked for indicators of metal abundance peculiarities and stellar binarity in a sample of 40 confirmed gamma Dor stars. Absolute magnitudes from Hipparcos parallaxes and UV magnitudes, from the S2/S68 experiment on board the TD1 satellite, are retrieved from databases and compared with predicted values. A set of non variable normal stars is used to check the consistency of this analysis and also serve as reference stars. Twenty-nine stars of the gamma Dor star sample, which is 73% of it, are discovered having abnormal UV fluxes constantly showing UV flux excesses compared to those computed with the atmospheric parameters (Teff, logg, and metallicity) determined from calibration of the uvbyBeta indices. The reason for this UV excess of flux at 196.5nm and at 236.5nm, which was previously known only for HD 209295, cannot be ascribed to binarity alone. An extra source of UV flux or less UV absorption - yet unknown - must be present.
319. V392 Car light curve
- ID:
- ivo://CDS.VizieR/J/A+A/374/204
- Title:
- V392 Car light curve
- Short Name:
- J/A+A/374/204
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed study of an eclipsing binary which had been classified Ap SrCrEu (Hartoog, 1976ApJ...205..807H) before being known as a binary. Radial velocities measured at the times of both quadratures allow us to obtain precise masses for both components, while the light curve yields the radii. The following ephemeris and fundamental parameters of the system were obtained: HJD=(2447999.7656+/-0.0041) +(3.174990+/-0.000001) E, e=0.00, i=81.9+/-0.1{deg}, M_1_=1.90+/-0.02M_{sun}_, M_2_=1.85+/-0.02M_{sun}_, R_1_=1.63+/-0.03R_{sun}_, R_2_=1.60+/-0.03R_{sun}_, vsini_1_=27.6+/-3.5km/s, vsini_2_=23.6+/-3.6km/s. The projected rotational velocities were determined by fitting a synthetic spectrum convolved with a rotational profile to the observed spectrum. A comparison of the spectra of V392 Car and of the normal A star Cox 98, which has the same colour indices, shows that Sr is not overabundant and the metallicity of V392 Car is the same as that of the other cluster members. Therefore, V392 Car is a normal A2 star rather than an Ap star. The position of V392 Car in the HR diagram is entirely consistent with membership of the cluster NGC 2516. An independent estimate of the distance to this cluster was done using the parameters of the eclipsing system, and found to be in agreement with the Hipparcos one. A comparison of the parameters obtained from observations with predictions of internal structure models leads to a metallicity estimate [M/H]=0+/-0.10dex for NGC 2516. This estimate is completely independent of any spectroscopic or photometric method (except for the T_eff_ determination) but relies on stellar structure models.
- ID:
- ivo://CDS.VizieR/J/AJ/142/87
- Title:
- Velocities and light curves of V350 Sgr
- Short Name:
- J/AJ/142/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- "The Cepheid Mass Problem" is one of the fundamental tests of the understanding of stellar evolution. One of the foundations of measured masses for Cepheids for this question is binary orbits. V350 Sgr is a classical Cepheid in a binary system. New radial velocity data for the system have been obtained over the last several years, and are used to update the orbit. The secondary in the system has previously had its orbital velocity amplitude measured in the ultraviolet with the Hubble Space Telescope. This amplitude has been combined with the new orbit and the adopted mass of the secondary resulting in a Cepheid mass of 5.0+/-0.8M_{sun}_.
