- ID:
- ivo://CDS.VizieR/J/ApJ/883/8
- Title:
- Cand. young OB stars from GALEX & Gaia DR2
- Short Name:
- J/ApJ/883/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine Galaxy Evolution Explorer and Gaia DR2 catalogs to track star formation in the outskirts of our Galaxy. Using photometry, proper motions, and parallaxes we identify a structure of ~300 OB-type candidates located between 12 and 15kpc from the Galactic center that are kinematically cold. The structure is located between l=120{deg} and 200{deg}, above the plane up to ~700pc and below the plane to ~1kpc. The bulk motion is disklike; however, we measure a mean upward vertical motion of 5.7+/-0.4km/s, and a mean outward radial motion of between 8 and 16km/s. The velocity dispersion along the least dispersed of its proper-motion axes (perpendicular to the Galactic disk) is 6.0+/-0.3km/s, confirming the young age of this structure. While spatially encompassing the outer spiral arm of the Galaxy, this structure is not a spiral arm. Its explanation as the Milky Way warp is equally unsatisfactory. The structure's vertical extent, mean kinematics, and asymmetry with respect to the plane indicate that its origin is more akin to a wobble generated by a massive satellite perturbing the Galaxy's disk. The mean stellar ages in this outer structure indicate the event took place some 200Myr ago.
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- ID:
- ivo://CDS.VizieR/I/6
- Title:
- Cape Catalog of 20554 Faint Stars, -40 to -52{deg}
- Short Name:
- I/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains positions, precessions, proper motions, and photographic magnitudes for 20,554 stars. These were derived from photographs taken at the Royal Observatory, Cape of Good Hope between 1923 and 1928. It covers the astrographic zones -40 degrees to -52 degrees of declination. The positions are given for epoch 1900 (1900.0). It includes spectral types for many of the stars listed. It extends the earlier catalogs derived from the same plates to fainter magnitudes. The computer-readable version consists of a single data table. The stated probable error for the star positions is 0.024 seconds of time (R.A.) and 0.25 seconds of arc (Dec.) for stars with one determination, 0.017 seconds of time, and 0.18 seconds of arc for two determinations, and 0.014 / 0.15 for stars with three determinations. The precession and secular variations were derived from Newcomb's constants. The authors quote probable errors of the proper motions in both coordinates of 0.008 seconds of arc for stars with one determination, 0.0055 seconds for stars with two determinations, and 0.0044 for stars with three. The photographic magnitudes were derived from the measured diameters on the photographic plates and from the magnitudes given in the Cape Photographic Durchmusterung. The spectral classification of the catalogued stars was done with the assistance of Annie Jump Cannon of the Harvard College Observatory. The user should consult the source reference for more details of the measurements and reductions. See also the notes in this document for additional information on the interpretation of the entries.
- ID:
- ivo://CDS.VizieR/I/116
- Title:
- Cape Photographic Catalog 1950.0 (CPC)
- Short Name:
- I/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog includes most of the stars from the 1900.0 Cordoba Zone Catalogues B and C in the zone -30 deg. -35 deg. at the equinox of 1925.0. Some of the fainter Cordoba stars have been omitted in the rather crowded regions in the Milky Way. The aim was to provide accurate places for an average of 9 to 10 stars per square degree as a reference for a rereduction of the AG positions. Most of the stars have visual magnitudes between 7 and 10. Positions and proper motions have been supplied from the General Catalogue for those stars that were too bright for accurate measurement on photographic plates. The positions are on the FK3 system for the equinox of 1950.0. The probable errors of the positions are nominally +/- 0.15" in both right ascension and declination. That of the proper motions should not exceed +/- 1.4"/century, or +/-14 in the units in which the proper motions expressed in arc are given in the catalog.
- ID:
- ivo://CDS.VizieR/I/85
- Title:
- Cape Photographic Catalogue 2
- Short Name:
- I/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains the provisional positions for 51018 stars in the Cape zone -40 deg. to -52 deg., on the FK4 system for the equinox 1950.0. The internal mean error of a single coordinate obtained from the mean of r=four plates is estimated to be less than +/- 0.1" at the mean epoch of observation, about 1962. The systematic deviation from the FK4 system in a small area is probably also about +/-0.1". New proper motions have been determined for 22731 stars which are also in the Smithsonian Astrophysical Observatory (SAO) catalogue; the formal mean error of an annual proper motion in each coordinate is about +/-0.004"/a.
- ID:
- ivo://CDS.VizieR/J/ApJ/765/12
- Title:
- Carbon stars and DQ white dwarfs from SDSS-DR7+DR8
- Short Name:
- J/ApJ/765/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Among stars showing carbon molecular bands (C stars), the main-sequence dwarfs, likely in post-mass transfer binaries, are numerically dominant in the Galaxy. Via spectroscopic selection from the Sloan Digital Sky Survey, we retrieve 1220 high galactic latitude C stars, ~5 times more than previously known, including a wider variety than past techniques such as color or grism selection have netted, and additionally yielding 167 DQ white dwarfs. Of the C stars with proper motion measurements, we identify 69% clearly as dwarfs (dCs), while ~7% are giants. The dCs likely span absolute magnitudes M_i_ from ~6.5 to 10.5. "G-type" dC stars with weak CN and relatively blue colors are probably the most massive dCs still cool enough to show C_2_bands. We report Balmer emission in 22 dCs, none of which are G-types. We find 8 new DA/dC stars in composite spectrum binaries, quadrupling the total sample of these "smoking guns" for AGB binary mass transfer. Eleven very red C stars with strong red CN bands appear to be "N"-type AGB stars at large Galactocentric distances, one likely a new discovery in the dIrr galaxy Leo A. Two such stars within 30' of each other may trace a previously unidentified dwarf galaxy or tidal stream at ~40 kpc. We explore the multiwavelength properties of the sample and report the first X-ray detection of a dC star, which shows strong Balmer emission. Our own spectroscopic survey additionally provides the dC surface density from a complete sample of dwarfs limited by magnitude, color, and proper motion.
- ID:
- ivo://CDS.VizieR/J/ApJS/234/31
- Title:
- Carbon stars from LAMOST using machine learning
- Short Name:
- J/ApJS/234/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we present a catalog of 2651 carbon stars from the fourth Data Release (DR4) of the Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST). Using an efficient machine-learning algorithm, we find these stars from more than 7 million spectra. As a by-product, 17 carbon-enhanced metal- poor turnoff star candidates are also reported in this paper, and they are preliminarily identified by their atmospheric parameters. Except for 176 stars that could not be given spectral types, we classify the other 2475 carbon stars into five subtypes: 864 C-H, 226 C-R, 400 C-J, 266 C-N, and 719 barium stars based on a series of spectral features. Furthermore, we divide the C-J stars into three subtypes, C-J(H), C-J(R), and C-J(N), and about 90% of them are cool N-type stars as expected from previous literature. Besides spectroscopic classification, we also match these carbon stars to multiple broadband photometries. Using ultraviolet photometry data, we find that 25 carbon stars have FUV detections and that they are likely to be in binary systems with compact white dwarf companions.
- ID:
- ivo://CDS.VizieR/I/256
- Title:
- Carlsberg Meridian Catalogs
- Short Name:
- I/256
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This composite catalogue contains 180812 positions and magnitudes of 176591 stars north of declination -40deg, 155005 proper motions, and 25848 positions and magnitudes of 184 Solar System objects obtained with the Carlsberg Automatic Meridian Circle on La Palma during the period May 1984 to May 1998. It includes Carlsberg Meridian Catalogues Numbers 1 to 11 (CMC1-11); i.e. it comprises all the observations made since the instrument began operation on La Palma. The positions of the stars are for the epoch of observation and the equinox J2000.0, and are referred to the new International Celestial Reference Frame. The limiting magnitude is V=15.4. The catalogue mainly comprises positions and proper motions for the following programmes: 36000 International Reference Stars 30000 faint reference stars in a global net 18000 reference stars in the fields of radio sources 17000 stars in the Lick Northern Proper Motion catalogue 5000 reference stars for calibration of Schmidt plates 2600 stars in the Gliese catalogue of nearby stars 5000 stars in nearby OB associations 10500 F-type stars within 100 pc 9000 G-type dwarfs and giants, K-type giants stars within 300 pc 2200 unbiassed sample of K/M-type dwarf stars 19400 reference stars near Veron-Cetty galaxies 4700 variable stars (12-14 mag) in GCVS 12400 stars (11-14 mag) with pm>0".18/yr in NLTT and several smaller programmes mainly aimed at galactic kinematics. Positions and magnitudes of 12 novae and 8 supernovae which occurred in the years 1991 to 1998 are included. The catalogue also contains observations of the following Solar System objects: Callisto, Ganymede, Rhea, Titan, Iapetus, Hyperion, Uranus, Oberon, Neptune, Pluto and 173 minor planets and Comet P/Wild2. The mean error of a catalogue position in the zenith is 0".09 in right ascension and declination in CMC1-6, improving to 0".06 in CMC7-11. The accuracy in magnitude is 0.05 mag in CMC1-10, improving to 0.03 mag in CMC11. The mean error of the proper motions, derived by combining the position in this catalogue with those at earlier epochs, is typically in the range 0".003 to 0".004 per year. Cross-references are given to DM, AGK, SAO, HD and the double star catalogues ADS and WDS. The catalogue also contains 12216 mean annual observed positions of the FK5 stars used to transfer the instrumental system to the FK5 frame in the years 1984 to 1995. A compilation of all the meteorological data collected in the years 1984-1998, including the atmospheric extinction, is appended. This catalogue supersedes the previous versions which were numbered <I/126> (CMC1 and 2), <I/133> (CMC3), <I/147> (CMC4), <I/170> (CMC5), <I/189> (CMC6), <I/205> (CMC7) and <I/213> (CMC8).
- ID:
- ivo://CDS.VizieR/I/170A
- Title:
- Carlsberg Meridian Catalog, Vol. 5
- Short Name:
- I/170A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Carlsberg Meridian Catalogues give accurate positions, proper motions and magnitudes of stars north of declination -45deg and down to 15th magnitude. They also contain observations of the solar system objects: Mars, Callisto, Saturn, Titan, Iapetus, Uranus, Neptune, Pluto, and many minor planets. Typical mean errors for an entry are 0.1arcsec in position, 3mas/yr in proper motion, and 0.05mag in magnitude. The stars observed belong to a large number of observing programmes typically dealing with the reference frame or with galactic kinematics. The Carlsberg Automatic Meridian Circle on La Palma is operated by Copenhagen University Observatory, Royal Greenwich Observatory, and Real Instituto y Observatorio de la Armada at the Observatory del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. For a detailed introduction, please refer to the printed catalogue. A description of the programme may also be found in the 1993 paper by Fabricius (=1993BICDS..42....5F), from which the present description is derived. This 5th volume corresponds to observations made between May 1988 and January 1990
- ID:
- ivo://CDS.VizieR/I/189
- Title:
- Carlsberg Meridian Catalog, Vol. 6
- Short Name:
- I/189
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Carlsberg Meridian Catalogues give accurate positions, proper motions and magnitudes of stars north of declination -45deg and down to 15th magnitude. They also contain observations of the solar system objects: Mars, Callisto, Saturn, Titan, Iapetus, Uranus, Neptune, Pluto, and many minor planets. Typical mean errors for an entry are 0.1arcsec in position, 3mas/yr in proper motion, and 0.05mag in magnitude. The stars observed belong to a large number of observing programmes typically dealing with the reference frame or with galactic kinematics. The Carlsberg Automatic Meridian Circle on La Palma is operated by Copenhagen University Observatory, Royal Greenwich Observatory, and Real Instituto y Observatorio de la Armada at the Observatory del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. For a detailed introduction, please refer to the printed catalogue. A description of the programme may also be found in the 1993 paper by Fabricius (=1993BICDS..42....5F), from which the present description is derived. This 6th volume corresponds to observations made during the year 1990.
- ID:
- ivo://CDS.VizieR/I/213
- Title:
- Carlsberg Meridian Catalog, Vol. 8
- Short Name:
- I/213
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Carlsberg Meridian Catalogues give accurate positions, proper motions and magnitudes of stars north of declination -45deg and down to 15th magnitude. They also contain observations of the solar system objects: Mars, Callisto, Saturn, Titan, Iapetus, Uranus, Neptune, Pluto, and many minor planets. Typical mean errors for an entry are 0.1arcsec in position, 3mas/yr in proper motion, and 0.05mag in magnitude. The stars observed belong to a large number of observing programmes typically dealing with the reference frame or with galactic kinematics. The Carlsberg Automatic Meridian Circle on La Palma is operated by Copenhagen University Observatory, Royal Greenwich Observatory, and Real Instituto y Observatorio de la Armada at the Observatory del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. For a detailed introduction, please refer to the printed catalogue. A description of the programme may also be found in the 1993 paper by Fabricius (=1993BICDS..42....5F), from which the present description is derived. This 8th volume corresponds to observations made between August 1992 and December 1993.
