- ID:
- ivo://CDS.VizieR/J/PASP/122/35
- Title:
- Symbiotic stars on Asiago archive plates
- Short Name:
- J/PASP/122/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Asiago photographic archive has been searched for plates containing the symbiotic stars AS 210, AS 327, AX Per, BF Cyg, CI Cyg, DT Ser, EG And, GH Gem, Hen 2-442, Hen 3-1591, HM Sge, MaC 1-17, NSV 11776, Pe 2-16, Pt 1, PU Vul, RS Oph, T CrB, UV Aur, V1016 Cyg, V1329 Cyg, V352 Aql, V4018 Sgr, Wray 15-1470, and Z And. A total of 1617 good-quality plates imaging the program stars have been found and their brightness has been estimated using the Henden & Munari (2000, Cat. <J/A+AS/143/343>, 2001, Cat. <J/A+A/372/145>, 2006, Cat. <J/A+A/458/339>, 2008, Cat. <J/BaltA/17/293>) UBVRcIc local photometric sequences. The results for the objects with most abundant measurements are discussed.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/432/3186
- Title:
- Symbiotic stars towards the Galactic bulge
- Short Name:
- J/MNRAS/432/3186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Symbiotic stars are interacting binaries with the longest orbital periods, and their multicomponent structure makes them rich astrophysical laboratories. The accretion of a high-mass-loss-rate red giant wind on to a white dwarf (WD) makes them promising Type Ia supernova (SN Ia) progenitors. Systematic surveys for new Galactic symbiotic stars are critical to identify new promising SN Ia progenitors (e.g. RS Oph) and to better estimate the total population size to compare against SN Ia rates. Central to the latter objective is building a complete census of symbiotic stars towards the Galactic bulge. Here we report on the results of a systematic survey of H{alpha} emission-line stars covering 35 deg^2^. It is distinguished by the combination of deep optical spectroscopy and long-term light curves that improve the certainty of our classifications. A total of 20 bona fide symbiotic stars are found (13 S-types, 6 D-types and 1 D'-type), 35 per cent of which show the symbiotic specific Raman-scattered Ovi emission bands, as well as 15 possible symbiotic stars that require further study (six S-types and nine D-types). Light curves show a diverse range of variability including stellar pulsations (semi-regular and Mira), orbital variations and slow changes due to dust. Orbital periods are determined for five S-types and Mira pulsation periods for three D-types. The most significant D-type found is H1-45 and its carbon Mira with a pulsation period of 408.6d, corresponding to an estimated period-luminosity relation distance of ~6.2+/-1.4kpc and M_K_=-8.06+/-0.12mag. If H1-45 belongs to the Galactic bulge, then it would be the first bona fide luminous carbon star to be identified in the Galactic bulge population. The lack of luminous carbon stars in the bulge is a longstanding unsolved problem. A possible explanation for H1-45 may be that the carbon enhancement was accreted from the progenitor of the WD companion. A wide variety of unusual emission-line stars were also identified. These include central stars of planetary nebulae (PNe) [one (WC10-11) Wolf-Rayet and five with high-density cores], two novae, two WN6 Wolf-Rayet stars, two possible Be stars, a B[e] star with a bipolar outflow, an ultracompact HII region and a dMe flare star. Dust obscuration events were found in two central stars of PNe, increasing the known cases to five, as well as one WN6 star. There is considerable scope to uncover several more symbiotic stars towards the bulge, many of which are currently misclassified as PNe, provided that deep spectroscopy is combined with optical and near-infrared light curves.
- ID:
- ivo://CDS.VizieR/J/A+AS/143/343
- Title:
- Symbiotic stars UBV(RI)c photometry
- Short Name:
- J/A+AS/143/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present accurate UBV(RI)_C_ photometric sequences around 20 symbiotic stars. The sequences extend over wide brightness and color ranges, and are suited to cover quiescence as well as outburst phases. The sequences are intended to assist both present time photometry as well as measurement of photographic plates from historical archives.
- ID:
- ivo://CDS.VizieR/J/A+A/372/145
- Title:
- Symbiotic stars UBV(RI)c photometry. II.
- Short Name:
- J/A+A/372/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present accurate UBV(RI)_C_ photometric sequences for an additional 20 symbiotic stars. As for the 20 targets of Paper I (Henden et al., 2000, Cat. <J/A+AS/143/343>), the sequences extend over wide brightness and color ranges, and are suited to cover both quiescence and outburst phases. The sequences are intended to assist both present time photometry as well as measurement of photographic plates from historical archives.
- ID:
- ivo://CDS.VizieR/J/A+A/458/339
- Title:
- Symbiotic stars UBV(RI)c photometry. III.
- Short Name:
- J/A+A/458/339
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present accurate UBV(RI)_C_ photometric sequences and astrometric positions for a final set of 41 symbiotic stars. In a similar manner to the 40 targets of Papers I and II, these sequences extend over wide brightness and color ranges and are suited to covering both quiescence and outburst phases. They are intended to assist both the CCD photometric monitoring of current variability and exploitation of old photographic plates from historical archives.
- ID:
- ivo://CDS.VizieR/J/ApJS/240/21
- Title:
- Symbiotic stars with 2MASS, WISE & Gaia data
- Short Name:
- J/ApJS/240/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new census of Galactic and extragalactic symbiotic stars (SySts). This compilation contains 323 known and 87 candidate SySts. Of the confirmed SySts, 257 are Galactic and 66 extragalactic. The spectral energy distributions (SEDs) of 348 sources have been constructed using 2MASS and AllWISE data. Regarding the Galactic SySts, 74% are S types, 13% D, and 3.5% D'. S types show an SED peak between 0.8 and 1.7{mu}m, whereas D types show a peak at longer wavelengths between 2 and 4{mu}m. D' types, on the other hand, display a nearly flat profile. Gaia distances and effective temperatures are also presented. According to their Gaia distances, S types are found to be members of both thin and thick Galactic disk populations, while S+IR and D types are mainly thin disk sources. Gaia temperatures show a reasonable agreement with the temperatures derived from SEDs within their uncertainties. A new census of the OVI{lambda}6830 Raman-scattered line in SySts is also presented. From a sample of 298 SySts with available optical spectra, 55% are found to emit the line. No significant preference is found among the different types. The report of the OVI{lambda}6830 Raman-scattered line in non-SySts is also discussed as well as the correlation between the Raman-scattered OVI line and X-ray emission. We conclude that the presence of the OVI Raman-scattered line still provides a strong criterion for identifying a source as a SySt.
2267. System IMF of 25 Ori
- ID:
- ivo://CDS.VizieR/J/MNRAS/486/1718
- Title:
- System IMF of 25 Ori
- Short Name:
- J/MNRAS/486/1718
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The stellar initial mass function (IMF) is an essential input for many astrophysical studies but only in a few cases has it been determined over the whole cluster mass range, limiting the conclusions about its nature. The 25 Orionis group (25 Ori) is an excellent laboratory for investigating the IMF across the entire mass range of the population, from planetary-mass objects to intermediate/high-mass stars. We combine new deep optical photometry with optical and near-infrared data from the literature to select 1687 member candidates covering a 1.1{deg} radius area in 25 Ori. With this sample we derived the 25 Ori system IMF from 0.012 to 13.1M_{sun}_. This system IMF is well described by a two-segment power law with {GAMMA}=-0.74+/-0.04 for m<0.4M_{sun}_ and {GAMMA}=1.50+/-0.11 for m>=0.4M_{sun}_. It is also well described over the whole mass range by a tapered power-law function with {GAMMA}=1.10+/-0.09, mp=0.31+/-0.03 and {beta}=2.11+/-0.09. The best lognormal representation of the system IMF has mc=0.31+/-0.04 and {sigma}=0.46+/-0.05 for m<1M_{sun}_. This system IMF does not present significant variations with the radii. We compared the resultant system IMF as well as the brown dwarf/star ratio of 0.16+/-0.03 that we estimated for 25 Ori with that of other stellar regions with diverse conditions and found no significant discrepancies. These results support the idea that general star-formation mechanisms are probably not strongly dependent on environmental conditions. We found that the substellar and stellar objects in 25 Ori do not have any preferential spatial distributions and confirmed that 25 Ori is a gravitationally unbound stellar association.
- ID:
- ivo://CDS.VizieR/J/AJ/133/1470
- Title:
- TAROT suspected variable star catalog
- Short Name:
- J/AJ/133/1470
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- TAROT (Telescope a Action Rapide pour les Objets Transitoires) is a robotic observatory designed to observe very early optical transients of gamma-ray bursts (GRBs). As GRBs do not often occur, we use TAROT for various other celestial targets spread over the sky. For every field observed by TAROT, we computed the magnitudes of every star. From this work, we found 1175 new variable stars brighter than 17mag. We selected the best variable star candidates and compiled them in the TSVSC1 (TAROT Suspected Variable Star Catalog, ver. 1), which also contains Fourier-series coefficients that fit the light curves.
- ID:
- ivo://CDS.VizieR/II/230
- Title:
- TASS Mark III photometric survey
- Short Name:
- II/230
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Amateur Sky Survey (TASS) is a loose confederation of amateur and professional astronomers. We describe the design and construction of our Mark III system, a set of wide-field drift-scan CCD cameras which monitor the celestial equator down to 13th magnitude in several passbands. We explain the methods by which images are gathered, processed, and reduced into lists of stellar positions and magnitudes. Over the period 1996 October to 1998 November, we compiled a large database of photometric measurements. One of our results is the tenxcat catalog, which contains measurements on the standard Johnson-Cousins system for 367,241 stars; it contains links to the light curves of these stars as well.
- ID:
- ivo://CDS.VizieR/J/ApJS/176/457
- Title:
- Taurus dark cloud background star catalog
- Short Name:
- J/ApJS/176/457
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Normal field stars located behind dense clouds are a valuable resource in interstellar astrophysics, as they provide continua in which to study phenomena such as gas-phase and solid-state absorption features, interstellar extinction, and polarization. This paper reports the results of a search for highly reddened stars behind the Taurus Dark Cloud complex. We use the Two Micron All Sky Survey (2MASS) Point Source Catalog to survey a ~50deg^2^ area of the cloud to a limiting magnitude of Ks=10.0. Photometry in the 1.2-2.2um passbands from 2MASS is combined with photometry at longer infrared wavelengths (3.6-12um) from the Spitzer Space Telescope and the Infrared Astronomical Satellite to provide effective discrimination between reddened field stars and young stellar objects (YSOs) embedded in the cloud. Our final catalog contains 248 confirmed or probable background field stars, together with estimates of their total visual extinctions, which span the range 2<A_V_<29mag. We also identify the 2MASS source J04292083+2742074 (IRAS 04262+2735) as a previously unrecognized candidate YSO, based on the presence of infrared emission greatly in excess of that predicted for a normal reddened photosphere at wavelengths >5um.
