- ID:
- ivo://CDS.VizieR/J/A+A/526/A6
- Title:
- Central stars of galactic planetary nebulae
- Short Name:
- J/A+A/526/A6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- There are more than 3000 confirmed and probable known Galactic planetary nebulae (PNe), but central star spectroscopic information is available for only 13% of them. We undertook a spectroscopic survey of central stars of PNe at low resolution and compiled a large list of central stars for which information was dispersed in the literature. We present a catalogue of 492 confirmed and probable CSPN and provide a preliminary spectral classification for 45 central star of PNe. This revises previous values of the proportion of CSPN with atmospheres poor in hydrogen in at least 30% of cases and provide statistical information that allows us to infer the origin of H-poor stars. Based on data collected at the Complejo Astronomico El Leoncito (CASLEO), which is operated under agreement between the Consejo Nacional de Investigaciones Cientificas y Tecnicas de la Republica Argentina y Universidades Nacionales de La Plata, Cordoba y San Juan, Argentina.
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- ID:
- ivo://CDS.VizieR/J/A+A/531/A172
- Title:
- Central stars of planetary nebulae. II.
- Short Name:
- J/A+A/531/A172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- There are more than 3000 confirmed and probably known Galactic planetary nebulae (PNe), but central star spectroscopic information is available for only 13% of them. We have undertaken a spectroscopic survey of the central stars in PNe to identify their spectral types. We performed spectroscopic observations at low resolution with the 2-m telescope at CASLEO, Argentina. We present the spectra of 46 central stars of PNe, most of them are OB-type and emission-line stars.
- ID:
- ivo://CDS.VizieR/J/A+A/638/A103
- Title:
- Central stars of planetary nebulae in Gaia DR2
- Short Name:
- J/A+A/638/A103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate distance measurements are fundamental to the study of planetary nebulae (PNe) but they have long been elusive. The most accurate and model-independent distance measurements for galactic PNe come from the trigonometric parallaxes of their central stars, which were only available for a few tens of objects prior to the Gaia mission. The accurate identification of PN central stars (CSPNe) in the Gaia source catalogues is a critical prerequisite for leveraging the unprecedented scope and precision of the trigonometric parallaxes measured by Gaia. Our aim is to build a complete sample of PN central star detections with minimal contamination. We developed and applied an automated technique based on the likelihood ratio method to match candidate central stars in Gaia Data Release 2 (DR2) to known PNe in the Hong Kong/AAO/Strasbourg H{alpha} (HASH) PN catalogue (Parker et al. 2016, 2016JPhCS.728c2008P), taking into account the BP-RP colours of the Gaia sources as well as their positional offsets from the nebula centres. These parameter distributions for both true central stars and background sources were inferred directly from the data. We present a catalogue of over 1000 Gaia sources that our method has automatically identified as likely PN central stars. We demonstrate how the best matches enable us to trace nebula and central star evolution and to validate existing statistical distance scales, and we discuss the prospects for further refinement of the matching based on additional data. We also compare the accuracy of our catalogue to that of previous works.
- ID:
- ivo://CDS.VizieR/J/ApJ/722/L120
- Title:
- Central surface brightness of 30000 SDSS galaxies
- Short Name:
- J/ApJ/722/L120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Disc central surface brightness for 30000 galaxies from the Sloan Digitized Sky Survey (SDSS) Data Release 7, in the r-band. Virtual Observatory methods and tools were used to define, retrieve and analyze the images for this unprecedentedly large sample classified as spiral galaxies in the LEDA catalogue. These parameters are also available for all other SDSS bands (u,g,i,z), and they can be retrieved from the Author.
- ID:
- ivo://CDS.VizieR/J/ApJ/827/L19
- Title:
- Central surface densities in SPARC disk galaxies
- Short Name:
- J/ApJ/827/L19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the Spitzer Photometry and Accurate Rotation Curves (SPARC) database to study the relation between the central surface density of stars {Sigma}_*_(0) and dynamical mass {Sigma}_dyn_(0) in 135 disk galaxies (S0 to dIrr). We find that {Sigma}_dyn_(0) correlates tightly with {Sigma}_*_(0) over 4dex. This central density relation can be described by a double power law. High surface brightness galaxies are consistent with a 1:1 relation, suggesting that they are self-gravitating and baryon dominated in the inner parts. Low surface brightness (LSB) galaxies systematically deviate from the 1:1 line, indicating that the dark matter contribution progressively increases but remains tightly coupled to the stellar one. The observed scatter is small (~0.2dex) and largely driven by observational uncertainties. The residuals show no correlations with other galaxy properties like stellar mass, size, or gas fraction.
- ID:
- ivo://CEFCA
- Title:
- Centro de Estudios de Física del Cosmos de Aragón (CEFCA)
- Short Name:
- CEFCA
- Date:
- 17 Jul 2018 09:00:00
- Publisher:
- Centro de Estudios de Física del Cosmos de Aragón (CEFCA)
- Description:
- This naming authority is the root of the naming of the resources
- ID:
- ivo://CDS.VizieR/J/AJ/126/1362
- Title:
- Century Survey Galactic Halo Project. I.
- Short Name:
- J/AJ/126/1362
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Century Survey Galactic Halo Project is a photometric and spectroscopic survey from which we select relatively blue stars (V-R<0.30mag) as probes of the Milky Way halo. The survey strip spans the range of Galactic latitude 35{deg}<b<88{deg}, allowing us to study the nature of populations of stars and their systematic motions as a function of Galactic latitude. One of our primary goals is to use blue horizontal-branch stars to trace potential star streams in the halo, and to test the hierarchical model for the formation of the Galaxy. In this paper we discuss spectroscopy and multipassband photometry for a sample of 764 blue stars in the Century Survey region. Our sample consists predominantly of A- and F-type stars. We describe our techniques for determination of radial velocities, effective temperatures, metallicities, and surface gravities. Based on these measurements, we derive distance estimates by comparison with a set of calibrated isochrones. We devote special attention to the classification of blue horizontal-branch stars, and compare the results obtained from the application of the techniques of Kinman et al. 1994, Cat. <J/AJ/108/1722>, Wilhelm et al. (1999, Cat. <J/AJ/117/2308>), and Clewley et al. (2002MNRAS.337...87C). We identify 55 blue horizontal-branch stars. Our large sample of stars also uncovers a number of unusual objects, including three carbon-enhanced stars, a late B-type star located 0.8kpc above the Galactic plane, and a DZ white dwarf.
3278. Cep A X-Ray sources
- ID:
- ivo://CDS.VizieR/J/ApJ/626/272
- Title:
- Cep A X-Ray sources
- Short Name:
- J/ApJ/626/272
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of X-rays from both components of Cepheus A, East and West, with the XMM-Newton observatory. HH 168 joins the ranks of other energetic Herbig-Haro objects that are sources of T>=10^6^K X-ray emission. We detect 102 X-ray sources, many presumed to be premain-sequence stars on the basis of the reddening of their optical and IR counterparts.
- ID:
- ivo://nasa.heasarc/cepbob3oid
- Title:
- Cep B/OB3 Star-Forming Region Chandra Point Source Optical/IR IDs Catalog
- Short Name:
- CEPBOB3OID
- Date:
- 25 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Cepheus B (Cep B) molecular cloud and a portion of the nearby Cep OB3b OB association, one of the most active regions of star formation within 1 kpc, have been observed with the Infrared Array Camera (IRAC) detector on board the Spitzer Space Telescope. The goals were to study protoplanetary disk evolution and processes of sequential triggered star formation in the region. Out of ~400 pre-main-sequence (PMS) stars selected with an earlier Chandra X-ray Observatory observation, ~95% are identified with mid-infrared sources and most of these are classified as diskless or disk-bearing stars. The discovery of the additional >200 IR-excess low-mass members gives a combined Chandra+Spitzer PMS sample that is almost complete down to 0.5 * M<sub>sun</sub> outside of the cloud, and somewhat above 1 * M<sub>sun</sub> in the cloud. The X-ray observations of the Cep B/Cep OB3b region and their data analysis are described in detail by Getman et al. (2006, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/163/306">CDS Cat. J/ApJS/163/306</a>, HEASARC CEPBOB3CXO table). The 30 ks exposure was obtained on 2003 March 11.51-11.88 with the Advanced CCD Imaging Spectrometer (ACIS) detector on board the Chandra X-ray Observatory as part of the ACIS Instrument Team's Guaranteed Time Observations (ObsId No. 3502, P.I.: G. Garmire). The mid-IR observation of Cep B and Cep OB3b was obtained on 2007 February 18 with the IRAC detector on the Spitzer Space Telescope in the 3.6, 4.5, 5.8, and 8.0 micron channels. This was a General Observer project (program identification No. 30361; P.I.: J. Wang). This table contains the optical and infrared counterpart information on the 431 X-ray sources detected by Chandra. It does not contain the 224 IR-excess objects which were not detected as X-ray sources (listed in Table 3 of the reference paper) that are thought to be additional low-mass members of this complex. This table was created by the HEASARC in August 2011 primarily based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/699/1454">CDS catalog J/ApJ/699/1454</a> files table.dat and table 2.dat which list the optical and infrared counterpart information on the 431 X-ray sources detected by Chandra. The names and positions of these X-ray sources were taken from the Getman et al. (2006, ApJS, 163, 306) Catalog, which is available as the HEASARC Browse table CEPBOB3CXO. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cepbob3cxo
- Title:
- Cep B/OB3 Star-Forming Region Chandra X-Ray Point Source Catalog
- Short Name:
- CEPBOB3CXO
- Date:
- 25 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the Cepheus B star formation region (the Cep B molecular cloud and the Cep OB3b OB association) Chandra X-Ray point source catalog. The Cepheus B (Cep B) molecular cloud and a portion of the nearby Cep OB3b OB association, one of the most active regions of star formation within 1 kpc, have been observed with the ACIS detector on board the Chandra X-Ray Observatory. 431 X-ray sources have been detected, of which 89% are confidently identified as clustered pre-main-sequence (PMS) stars. Two main results are obtained. First, the best census to date for the stellar population of the region has been made, with many members of two rich stellar clusters, the lightly obscured Cep OB3b association and the deeply embedded cluster in Cep B, whose existence was previously traced only by a handful of radio sources and T Tauri stars, being identified. Second, a discrepancy between the X-ray luminosity functions of the Cep OB3b and the Orion Nebula cluster has been found. This may be due to the different initial mass functions of the two regions (an excess of ~=0.3 M_solar stars) or different age distributions. Several other results are obtained. A diffuse X-ray component seen in the field is attributed to the integrated emission of unresolved low-mass PMS stars. The X-ray emission from HD 217086 (O7n), the principle ionizing source of the region, follows the standard model, involving many small shocks in an unmagnetized radiatively accelerated wind. X-ray source 294 joins a number of similar superflare PMS stars for which long magnetic structures may connect the protoplanetary disk to the stellar surface. The Chandra observation of Cep B and Cep OB3b was obtained on 2003 March 11.51-11.88 with the ACIS camera. Only results from the imaging array (ACIS-I) covering about 17' x 17' on the sky are considered here. The aim point of the array was 22 56 49.4 +62 39 55.6 (J2000.0 RA and Dec), and the satellite roll angle was 7.9 degrees. The total net exposure time was 30 ksec, with no background flaring or data losses. This table was created by the HEASARC in February 2007 based on the merger of electronic versions of tables 1, 2 and 3 from the above reference which were obtained from the ApJS website. This is a service provided by NASA HEASARC .
