- ID:
- ivo://CDS.VizieR/J/AJ/150/77
- Title:
- Catalog of hypervelocity candidate stars
- Short Name:
- J/AJ/150/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we analyze a sample of metal-rich (>-0.8dex) main sequence stars in the extended solar neighborhood, investigating kinematic outliers from the background population. The data, which are taken from the Sloan Digital Sky Survey, are kinematically profiled as a function of distance from the Galactic plane using full six-dimensional phase space information. Each star is examined in the context of these kinematic profiles and likelihoods are assigned to quantify whether a star matches the underlying profile. Since some of these stars are likely to have been ejected from the disk, we trace back their orbits in order to determine potential ejection radii. We find that objects with low probability (i.e., "outliers") are typically more metal-poor, faster and, most importantly, have a tendency to originate from the inner Galaxy compared to the underlying population. We also compose a sample of stars with velocities exceeding the local escape velocity. Although we do not discount that our sample could be contaminated by objects with spurious proper motions, a number of stars appear to have been ejected from the disk with exceptionally high velocities. Some of these are consistent with being ejected from the spiral arms and hence are a rich resource for further study. Finally we look at objects whose orbits are consistent with them being ejected at high speeds from the Galactic center. Of these objects we find that one, J135855.65+552538.19, is inconsistent with halo, bulge and disk kinematics and could plausibly have been ejected from the Galactic nucleus via a Hills mechanism.
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Search Results
- ID:
- ivo://CDS.VizieR/J/PASP/132/E4301
- Title:
- Catalog of Infrared Dark Clouds
- Short Name:
- J/PASP/132/E4301
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The field of computer vision has greatly matured in the past decade, and many of the methods and techniques can be useful for astronomical applications. One example is in searching large imaging surveys for objects of interest, especially when it is difficult to specify the characteristics of the objects being searched for. We have developed a method using contour finding and convolution neural networks (CNNs) to search for Infrared Dark Clouds (IRDCs) in the Spitzer Galactic plane survey data. IRDCs can vary in size, shape, orientation, and optical depth, and are often located near regions with complex emission from molecular clouds and star formation, which can make the IRDCs difficult to reliably identify. False positives can occur in regions where emission is absent, rather than from a foreground IRDC. The contour finding algorithm we implemented found most closed figures in the mosaic and we developed rules to filter out some of the false positive before allowing the CNNs to analyze them. The method was applied to the Spitzer data in the Galactic plane surveys, and we have constructed a catalog of IRDCs which includes additional parts of the Galactic plane that were not included in earlier surveys.
- ID:
- ivo://CDS.VizieR/II/225
- Title:
- Catalog of Infrared Observations, Edition 5
- Short Name:
- II/225
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Catalog of Infrared Observations and its associated data base comprise a summary of infrared astronomical observations published in the scientific literature from 1965 through 1997 in the wavelength range 1 micrometer - 1 mm. The database contains infrared observational data for sources outside the Solar System, constructed through a search of the most active scientific journals, IR surveys and catalogs. To date, about 6200 journal articles and 10 major survey catalogs have been included in the data base, which contains 374,653 individual observations of about 62,000 different infrared sources. More than 8,000 of these sources are identifiable with visible objects. The bibliographical files link observations in the catalog with the original articles published in the literature. References give the standard information plus full titles. The Index of Infrared Source Positions is ordered alphabetically by source name and can be used to quickly locate sources in the position-ordered catalog. For sources with no published IR source position, a nominal position may have been given based on other sources. Nominal positions are usually the best available, but not necessarily the true IR positions. Nominal position references are indicated in the index.
- ID:
- ivo://CDS.VizieR/II/216
- Title:
- Catalog of Infrared Observations, Edition 4 (CIO)
- Short Name:
- II/216
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Catalog of Infrared Observations and its associated data base comprise a summary of infrared astronomical observations published in the scientific literature from 1965 through 1995 in the wavelength range 1 micrometer - 1 mm. The database contains infrared observational data for sources outside the Solar System, constructed through a search of the most active scientific journals, IR surveys and catalogs. To date, about 6195 journal articles and 10 major survey catalogs have been included in the data base, which contains more than 325,000 individual observations of about 55,000 different infrared sources. More than 8,000 of these sources are identifiable with visible objects. The bibliographical files link observations in the catalog with the original articles published in the literature. References give the standard information plus full titles. The Index of Infrared Source Positions is ordered alphabetically by source name and can be used to quickly locate sources in the position-ordered catalog. For sources with no published IR source position, a nominal position may have been given based on other sources. Nominal positions are usually the best available, but not necessarily the true IR positions. Nominal position references are indicated in the index.
- ID:
- ivo://CDS.VizieR/J/ApJS/232/26
- Title:
- Catalog of Kepler flare stars
- Short Name:
- J/ApJS/232/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to perform a statistical study of stellar flares observed by Kepler. We want to study the flare amplitude, duration, energy, and occurrence rates, and how they are related to the spectral type and rotation period. To that end, we have developed an automated flare detection and characterization algorithm. We have harvested the stellar parameters from the Kepler input catalog and the rotation periods from McQuillan et al. (2014, Cat. J/ApJS/211/24). We find several new candidate A stars showing flaring activity. Moreover, we find 653 giants with flares. From the statistical distribution of flare properties, we find that the flare amplitude distribution has a similar behavior between F+G types and K+M types. The flare duration and flare energy seem to be grouped between G+K+M types versus F types and giants. We also detect a tail of stars with high flare occurrence rates across all spectral types (but most prominent in the late spectral types), and this is compatible with the existence of "flare stars." Finally, we have found a strong correlation of the flare occurrence rate and the flare amplitude with the stellar rotation period: a quickly rotating star is more likely to flare often and has a higher chance of generating large flares.
- ID:
- ivo://CDS.VizieR/J/AJ/150/123
- Title:
- Catalog of 316 K giant candidates
- Short Name:
- J/AJ/150/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Infrared (IR) excesses around K-type red giants (RGs) have previously been discovered using Infrared Astronomy Satellite (IRAS) data, and past studies have suggested a link between RGs with overabundant Li and IR excesses, implying the ejection of circumstellar shells or disks. We revisit the question of IR excesses around RGs using higher spatial resolution IR data, primarily from the Wide-field Infrared Survey Explorer. Our goal was to elucidate the link between three unusual RG properties: fast rotation, enriched Li, and IR excess. Our sample of RGs includes those with previous IR detections, a sample with well-defined rotation and Li abundance measurements with no previous IR measurements, and a large sample of RGs asserted to be Li-rich in the literature; we have 316 targets thought to be K giants, about 40% of which we take to be Li-rich. In 24 cases with previous detections of IR excess at low spatial resolution, we believe that source confusion is playing a role, in that either (a) the source that is bright in the optical is not responsible for the IR flux, or (b) there is more than one source responsible for the IR flux as measured in IRAS. We looked for IR excesses in the remaining sources, identifying 28 that have significant IR excesses by ~20{mu}m (with possible excesses for 2 additional sources). There appears to be an intriguing correlation in that the largest IR excesses are all in Li-rich K giants, though very few Li-rich K giants have IR excesses (large or small). These largest IR excesses also tend to be found in the fastest rotators. There is no correlation of IR excess with the carbon isotopic ratio, ^12^C/^13^C. IR excesses by 20{mu}m, though relatively rare, are at least twice as common among our sample of Li-rich K giants. If dust shell production is a common by-product of Li enrichment mechanisms, these observations suggest that the IR excess stage is very short-lived, which is supported by theoretical calculations. Conversely, the Li-enrichment mechanism may only occasionally produce dust, and an additional parameter (e.g., rotation) may control whether or not a shell is ejected.
2637. Catalog of LMC HI clouds
- ID:
- ivo://CDS.VizieR/J/ApJS/171/419
- Title:
- Catalog of LMC HI clouds
- Short Name:
- J/ApJS/171/419
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 21cm neutral hydrogen interferometric survey of the Large Magellanic Cloud (LMC) combined with the Parkes multibeam HI single-dish survey (2003MNRAS.339...87S) clearly shows that the HI gas is distributed in the form of clumps or clouds. The HI clouds and clumps have been identified using a thresholding method with three separate brightness temperature thresholds (T_b_). Each catalog of HI cloud candidates shows a power-law relationship between the sizes and the velocity dispersions of the clouds roughly following the Larson law scaling {sigma}_v_{prop.to}R^0.5^, with steeper indices associated with dynamically hot regions. The clouds in each catalog have roughly constant virial parameters as a function of mass, suggesting that the clouds are all in roughly the same dynamical state, but the values of the virial parameter are significantly larger than unity, showing that turbulent motions dominate gravity in these clouds. The mass distribution of the clouds is a power law with differential indices between -1.6 and -2.0 for the three catalogs. In contrast, the distribution of mean surface densities is a lognormal distribution.
- ID:
- ivo://CDS.VizieR/J/MNRAS/473/30
- Title:
- Catalog of Ly{alpha} emitters
- Short Name:
- J/MNRAS/473/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a measurement of the fraction of Lyman {alpha} (Ly{alpha}) emitters (X_Ly{alpha}_) amongst HST continuum-selected galaxies at 3<z<6 with the Multi-Unit Spectroscopic Explorer (MUSE) on the VLT. Making use of the first 24 MUSE-Wide pointings in GOODS-South, each having an integration time of 1h, we detect 100Ly{alpha} emitters and find X_Ly{alpha}_>~0.5 for most of the redshift range covered, with 29 per cent of the Ly{alpha} sample exhibiting rest equivalent widths (rest-EWs)<=15{AA}. Adopting a range of rest-EW cuts (0~75{AA}), we find no evidence of a dependence of XLy{alpha} on either redshift or ultraviolet luminosity.
- ID:
- ivo://CDS.VizieR/II/134
- Title:
- Catalog of Magnetic Field Measurements
- Short Name:
- II/134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains references to all measurements of stellar magnetic fields published in the literature between 1958 and 1981. The catalog provides for each object identifications, position, magnitude, period, extrema of the magnetic field measured, number of measurements, method used, spectral type, bibliographic references, and notes.
- ID:
- ivo://CDS.VizieR/J/other/A+AT/23.213
- Title:
- Catalog of massive close binaries
- Short Name:
- J/other/A+AT/23.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains compilations of observable data for 176 massive close binaries with components earlier than approximately B5 of the main sequence are presented.
