- ID:
- ivo://CDS.VizieR/J/PASJ/62/525
- Title:
- SiO maser survey off the Galactic Plane
- Short Name:
- J/PASJ/62/525
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A group of Mira variables in the solar neighborhood shows unusual spatial motion in the Galaxy. To study this motion on a much larger scale in the Galaxy, we newly surveyed 134 evolved stars off the Galactic plane by SiO maser lines, obtaining accurate radial velocities of 84 detected stars. Together with the past data of SiO maser sources, we analyzed the radial-velocity data of a large sample of sources distributed in a distance range of about 0.3-6kpc in the first Galactic quadrant. At Galactic longitudes between 20{deg} and 40{deg}, we found a group of stars with large negative radial velocities, which deviate by more than 100km/s from the Galactic rotation. We show that these deviant motions of maser stars are created by periodic gravitational perturbation of the Bulge bar, and that the effect appears most strongly at radii between corotation and outer Lindblad resonances. The resonance effect can explain the displacement of positions from the Galactic plane as well.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/598/A76
- Title:
- Six infrared dark clouds multi-wavelength obs.
- Short Name:
- J/A+A/598/A76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Infrared dark clouds (IRDCs) are ubiquitous in the Milky Way, yet they play a crucial role in breeding newly-formed stars. In order to further understand the dynamics, chemistry, and evolution of IRDCs, we carried out multi-wavelength observations towards a small sample. We performed new observations with the IRAM 30m and CSO 10.4m telescopes, with tracers HCO^+^, HCN, N_2_H^+^, C^18^O, DCO^+^, SiO, and DCN towards six IRDCs G031.97+00.07, G033.69-00.01, G034.43+00.24, G035.39-00.33, G038.95-00.47, and G053.11+00.05.
- ID:
- ivo://CDS.VizieR/J/ApJS/74/181
- Title:
- Small-diameter radiosources catalogue
- Short Name:
- J/ApJS/74/181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A survey of the Galactic plane in the longitude range -20deg=<l<=120deg for Galactic latitudes |b|=<0.8deg has been carried out at 1400MHz using the VLA in the B configuration. We present here a catalog of the 1992 discrete sources detected in this survey which is ~75% complete to a limiting peak flux density of 25mJy for sources smaller than ~20" in diameter, although sources as faint as 8mJy and as large as 90" are also included. The catalog includes for each entry a position accurate to ~<3", peak and integrated flux densities, source extent, and information on counterparts both from earlier radio surveys of the plane (for which a comprehensive bibliography is included) and from the IRAS point source catalog. An extensive analysis of the integrity and completeness of the survey is presented here: in separate publications, we discuss the source content of the survey as derived from statistical analysis of the spatial distribution of the sources and from radio, optical and infrared follow up observations .
- ID:
- ivo://CDS.VizieR/J/PASP/126/219
- Title:
- Southern Galactic Be star candidates
- Short Name:
- J/PASP/126/219
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the result of a search for southern Galactic Be star candidates within the group of miscellaneous variables of the ASAS-2 catalog of variable stars, using statistical, morphological, photometric, and color criteria. This search lead us to obtain a catalog of 213 new Be star candidates. The I-band light curves of these candidates show outbursts (Type-1 stars) only in 9% of the sample, and stochastic variations (Type-4 stars) in 91% of the sample. We do not find stars showing clear high and low states (Type-2 stars) or showing outbursts and high and low states simultaneously (Type-1/Type-2 stars). Our sample of southern Galactic Be star candidates provide valuable new bright targets for high resolution spectroscopic studies with small/medium size telescopes.
- ID:
- ivo://CDS.VizieR/J/AJ/154/23
- Title:
- Southern H II Region Discovery Survey: pilot survey
- Short Name:
- J/AJ/154/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Southern H II Region Discovery Survey is a survey of the third and fourth quadrants of the Galactic plane that will detect radio recombination line (RRL) and continuum emission at cm-wavelengths from several hundred H II region candidates using the Australia Telescope Compact Array. The targets for this survey come from the WISE Catalog of Galactic H II Regions (Anderson et al. 2014, J/ApJS/212/1) and were identified based on mid-infrared and radio continuum emission. In this pilot project, two different configurations of the Compact Array Broad Band receiver and spectrometer system were used for short test observations. The pilot surveys detected RRL emission from 36 of 53 H II region candidates, as well as seven known H II regions that were included for calibration. These 36 recombination line detections confirm that the candidates are true H II regions and allow us to estimate their distances.
- ID:
- ivo://CDS.VizieR/VII/218
- Title:
- Southern Stars embedded in nebulosity
- Short Name:
- VII/218
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A survey of the Milky Way southward of the Palomar Sky Survey for the identification of reflection nebulae was carried out at the Cerro Tololo Inter-American Observatory in Chile. Plates in blue light were obtained at the Curtis Schmidt telescope covering a strip of plus or minus six degrees of the galactic equator. Red sensitive plates for comparison were also obtained with the same telescope covering the same area near the galactic plane. Observatory staff members and some students of the University of Toronto, Canada assisted in identifying stars embedded in nebulosity as shown by the plates. Although this catalogue roughly complements the Catalogue of Reflection Nebulae of van den Berg (1966AJ.....71..990V, Cat. <VII/21>), the region here surveyed is more narrowly confined to the galactic equator.
487. Spaghetti Survey
- ID:
- ivo://CDS.VizieR/J/AJ/120/2496
- Title:
- Spaghetti Survey
- Short Name:
- J/AJ/120/2496
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spaghetti project is a pencil-beam photometric and spectroscopic survey designed to identify structure in the Galactic halo. Four-color stellar photometry in the modified Washington filter set is used to identify halo stars for spectroscopic observations. The filters include C, M, T2 and DDO51. The fields in the survey are chosen from high Galactic-latitude positions with low reddening and no stars as bright as SAO stars. Thus far we have imaged 134 fields covering a total area of 52deg^2^. These fields are listed in table1.dat. Due to weather, the only fully calibrated photometry was measured from images taken with the BTC ccd mosaic camera on the CTIO 4m telescope in April 1999. Table4.dat lists these stars from the 53 BTC fields, which covers a total area of 13 square degrees. These data include only those stars whose measurement errors are less than 0.04 in all four filters (32655 total stars). Photometric measurements of stars in the other fields will be published as soon as they can be fully calibrated. See <GCPD/48> for a short description of the Washington Photometric system.
- ID:
- ivo://CDS.VizieR/J/AJ/152/31
- Title:
- Spectral classification of O Vz stars from GOSSS
- Short Name:
- J/AJ/152/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- On the basis of the Galactic O Star Spectroscopic Survey (GOSSS), we present a detailed systematic investigation of the O Vz stars. The currently used spectral classification criteria are rediscussed, and the Vz phenomenon is recalibrated through the addition of a quantitative criterion based on the equivalent widths of the HeI{lambda}4471, HeII{lambda}4542, and HeII{lambda}4686 spectral lines. The GOSSS O Vz and O V populations resulting from the newly adopted spectral classification criteria are comparatively analyzed. The locations of the O Vz stars are probed, showing a concentration of the most extreme cases toward the youngest star-forming regions. The occurrence of the Vz spectral peculiarity in a solar-metallicity environment, as predicted by the FASTWIND code, is also investigated, confirming the importance of taking into account several processes for the correct interpretation of the phenomenon.
- ID:
- ivo://CDS.VizieR/III/40A
- Title:
- Spectral Survey of Southern Milky Way
- Short Name:
- III/40A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The spectral survey, carried out at the Stockholm Observatory, was initiated by B. Lindblad. The observational material was obtained by L.O. Loden, K. Loden and others in the years 1956-1965, when the Stockholm Observatory took part in a joint enterprise for using the Harvard-Boyden station. The Swedish Natural Science Research Council, the Royal Academy of the Sciences, and the K. and A. Wallenberg Foundation funded the observations, which are based on both direct and objective prism plates. The data were published in three parts, the first having less precise positions than the others. The coordinates for Catalogue I (3033) were later recomputed with the same reduction procedure as Catalogues II (3034) and III (3035), making the present catalogue uniform (Andersen, 1977). The files include star identification, finding chart identification, RA and Dec, galactic longitude and latitude, spectral type, blue magnitude, visual magnitude and remarks. The data concerning the part 2 were revised by Brian Skiff in November 1996 (see the "History" section below)
- ID:
- ivo://CDS.VizieR/J/AJ/158/147
- Title:
- Spectrophotometric parallaxes with linear models
- Short Name:
- J/AJ/158/147
- Date:
- 07 Jan 2022 11:19:14
- Publisher:
- CDS
- Description:
- With contemporary infrared spectroscopic surveys like APO Galactic Evolution Experiment (APOGEE), red-giant stars can be observed to distances and extinctions at which Gaia parallaxes are not highly informative. Yet the combination of effective temperature, surface gravity, composition, and age-all accessible through spectroscopy - determines a giant's luminosity. Therefore spectroscopy plus photometry should enable precise spectrophotometric distance estimates. Here we use the overlap of APOGEE, Gaia, the Two Micron All Sky Survey (2MASS), and the Wide-field Infrared Survey Explorer (WISE) to train a data-driven model to predict parallaxes for red-giant branch stars with 0<logg=<2.2 (more luminous than the red clump). We employ (the exponentiation of) a linear function of APOGEE spectral pixel intensities and multiband photometry to predict parallax spectrophotometrically. The model training involves no logarithms or inverses of the Gaia parallaxes, and needs no cut on the Gaia parallax signal-to-noise ratio. It includes an L1 regularization to zero out the contributions of uninformative pixels. The training is performed with leave-out subsamples such that no star's astrometry is used even indirectly in its spectrophotometric parallax estimate. The model implicitly performs a reddening and extinction correction in its parallax prediction, without any explicit dust model. We assign to each star in the sample a new spectrophotometric parallax estimate; these parallaxes have uncertainties of less than 15%, depending on data quality, which is more precise than the Gaia parallax for the vast majority of targets, and certainly any stars more than a few kiloparsec distance. We obtain 10% distance estimates out to heliocentric distances of 20 kpc, and make global maps of the Milky Way's disk.
