- ID:
- ivo://CDS.VizieR/J/A+A/578/A100
- Title:
- Infrared massive stellar content of M83
- Short Name:
- J/A+A/578/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of point sources in the field of M83. Sources were first cataloged that were found in both Spitzer IRAC 3.6-micron and 4.5-micron images. These were then supplemented with 5.8 and 8.0-micron photometry. Ground-based near-IR photometry in J and Ks-bands were extracted from imaging from the FourStar camera on the Baade Magellan Telescope at Las Campanas Observatory. Optical photometry was extracted from Hubble Space Telescope Wide Field Camera 3 observations of seven fields covering much of the bright disk region of M83.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/160/268
- Title:
- Infrared photometry of binaries in Orion OB1
- Short Name:
- J/AJ/160/268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Statistics of low-mass pre-main-sequence binaries in the Orion OB1 association with separations ranging from 0.6" to 20" (220 to 7400au at 370pc) are studied using images from the VISTA Orion mini survey and astrometry from Gaia. The input sample based on the CVSO catalog contains 1137 stars of K and M spectral types (masses between 0.3 and 0.9M{odot}), 1021 of which are considered to be association members. There are 135 physical binary companions to these stars with mass ratios above ~0.13. The average companion fraction is 0.09{+/-}0.01 over 1.2 decades in separation, slightly less than, but still consistent with, the field. We found a difference between the Ori OB1a and OB1b groups, the latter being richer in binaries by a factor of 1.6{+/-}0.3. No overall dependence of the wide- binary frequency on the observed underlying stellar density is found, although in the Ori OB1a off-cloud population, these binaries seem to avoid dense clusters. The multiplicity rates in Ori OB1 and in sparse regions like Taurus differ significantly, hinting that binaries in the field may originate from a mixture of diverse populations.
- ID:
- ivo://CDS.VizieR/J/AJ/146/34
- Title:
- Infrared photometry of DA white dwarfs from LAMOST
- Short Name:
- J/AJ/146/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A total of ~640000 objects from the LAMOST pilot survey have been publicly released. In this work, we present a catalog of DA white dwarfs (DAWDs) from the entire pilot survey. We outline a new algorithm for the selection of white dwarfs (WDs) by fitting Sersic profiles to the Balmer H{beta}, H{gamma}, and H{delta} lines of the spectra, and calculating the equivalent width of the CaII K line. Two thousand nine hundred sixty-four candidates are selected by constraining the fitting parameters and the equivalent width of the CaII K line. All the spectra of candidates are visually inspected. We identify 230 DAWDs (59 of which are already included in the Villanova and SDSS WD catalogs), 20 of which are DAWDs with non-degenerate companions. In addition, 128 candidates are classified as DAWDs/subdwarfs, which means the classifications are ambiguous. The result is consistent with the expected DAWD number estimated based on the LEGUE target selection algorithm.
- ID:
- ivo://CDS.VizieR/J/AJ/160/253
- Title:
- Infrared photometry of late-type dwarfs in Kepler Field
- Short Name:
- J/AJ/160/253
- Date:
- 08 Dec 2021
- Publisher:
- CDS
- Description:
- While it is well-established that giant-planet occurrence rises rapidly with host star metallicity, it is not yet clear if small-planet occurrence around late-type dwarf stars depends on host star metallicity. Using the Kepler Data Release 25 planet candidate list and its completeness data products, we explore planet occurrence as a function of metallicity in the Kepler field's late-type dwarf stellar population. We find that planet occurrence increases with metallicity for all planet radii Rp down to at least Rp~2R{Earth}, and that in the range 2R{Earth}<~Rp<~5R{Earth}, planet occurrence scales linearly with metallicity Z. Extrapolating our results, we predict that short-period planets with Rp<~2R{Earth} should be rare around early-M dwarf stars with [M/H]<~-0.5 or late-M dwarf stars with [M/H]<~+0.0. This dependence of planet occurrence on metallicity observed in the Kepler field emphasizes the need to control for metallicity in estimates of planet occurrence for late-type dwarf stars like those targeted by Kepler's K2 extension and the Transiting Exoplanet Survey Satellite. We confirm the theoretical expectation that the small-planet occurrence-host star metallicity relation is stronger for low-mass stars than for solar-type stars. We establish that the expected solid mass in planets around late-type dwarfs in the Kepler field is comparable to the total amount of planet-making solids in their protoplanetary disks. We argue that this high efficiency of planet formation favors planetesimal accretion over pebble accretion as the origin of the small planets observed by Kepler around late-type dwarf stars.
- ID:
- ivo://CDS.VizieR/J/A+A/609/A102
- Title:
- Inner/outer HII regions: galaxy sample
- Short Name:
- J/A+A/609/A102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using integral field spectroscopy (IFS) observations we aim to perform a systematic study and comparison of two inner and outer HII regions samples. The spatial resolution of the IFS, the number of objects and the homogeneity and coherence of the observations allow a complete characterization of the main observational properties and differences of the regions. We analyzed a sample of 725 inner HII regions and a sample of 671 outer HII regions, all of them detected and extracted from the observations of a sample of 263 nearby, isolated, spiral galaxies observed by the CALIFA survey. We find that inner HII regions show smaller equivalent widths, greater extinction and luminosities, along with greater values of [NII] {lambda}6583/H{alpha} and [OII] {lambda}3727/[OIII] {lambda}5007 emission-line ratios, indicating higher metallicities and lower ionization parameters. Inner regions have also redder colors and higher photometric and ionizing masses, although Mion/Mphot is slightly higher for the outer regions. This work shows important observational differences between inner and outer HII regions in star forming galaxies not previously studied in detail. These differences indicate that inner regions have more evolved stellar populations and are in a later evolution state with respect to outer regions, which goes in line with the inside-out galaxy formation paradigm.
- ID:
- ivo://CDS.VizieR/J/A+A/504/681
- Title:
- Integrated BVJHKs for 650 open clusters
- Short Name:
- J/A+A/504/681
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We determine the integrated magnitudes and colours of 650 clusters in optical (BV) and the near-infrared (JHKs) passbands and construct the luminosity functions of the Galactic open clusters in these passbands.
- ID:
- ivo://CDS.VizieR/J/MNRAS/403/1491
- Title:
- Integrated magnitudes of synthetic star clusters
- Short Name:
- J/MNRAS/403/1491
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents integrated magnitudes and colours for synthetic clusters. The integrated parameters have been obtained for the whole cluster population as well as for the main-sequence (MS) population of star clusters. We have also estimated observed integrated magnitudes and colours of the MS population of galactic open clusters, Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) star clusters.
- ID:
- ivo://CDS.VizieR/J/ApJ/846/159
- Title:
- Interferometric CO obs. of 126 CALIFA galaxies
- Short Name:
- J/ApJ/846/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present interferometric CO observations, made with the Combined Array for Millimeter-wave Astronomy (CARMA) interferometer, of galaxies from the Extragalactic Database for Galaxy Evolution survey (EDGE). These galaxies are selected from the Calar Alto Legacy Integral Field Area (CALIFA) sample, mapped with optical integral field spectroscopy. EDGE provides good-quality CO data (3{sigma} sensitivity {Sigma}_mol_~11M_{sun}/pc^2^ before inclination correction, resolution ~1.4kpc) for 126 galaxies, constituting the largest interferometric CO survey of galaxies in the nearby universe. We describe the survey and data characteristics and products, then present initial science results. We find that the exponential scale lengths of the molecular, stellar, and star-forming disks are approximately equal, and galaxies that are more compact in molecular gas than in stars tend to show signs of interaction. We characterize the molecular-to-stellar ratio as a function of Hubble type and stellar mass and present preliminary results on the resolved relations between the molecular gas, stars, and star-formation rate. We then discuss the dependence of the resolved molecular depletion time on stellar surface density, nebular extinction, and gas metallicity. EDGE provides a key data set to address outstanding topics regarding gas and its role in star formation and galaxy evolution, which will be publicly available on completion of the quality assessment.
- ID:
- ivo://CDS.VizieR/J/AJ/160/37
- Title:
- Intergalac. medium opacity from Lyman-break galaxies
- Short Name:
- J/AJ/160/37
- Date:
- 08 Dec 2021
- Publisher:
- CDS
- Description:
- We measure the effective opacity ({tau}_eff_) of the intergalactic medium from the composite spectra of 281 Lyman-break galaxies in the redshift range 2<~z<~3. Our spectra are taken from the COSMOS Ly{alpha} Mapping And Tomographic Observations survey derived from the Low Resolution Imaging Spectrometer on the W.M. Keck I telescope. We generate composite spectra in two redshift intervals and fit them with spectral energy distribution (SED) models composed of simple stellar populations. Extrapolating these SED models into the Ly{alpha} forest, we measure the effective Ly{alpha} opacity ({tau}_eff_) in the 2.02<~z<~2.44 range. At z=2.22, we estimate {tau}_eff_=0.159{+/-}0.001 from a power-law fit to the data. These measurements are consistent with estimates from quasar analyses at z<2.5 indicating that the systematic errors associated with normalizing quasar continua are not substantial. We provide a Gaussian processes model of our results and previous {tau}_eff_ measurements that describes the steep redshift evolution in {tau}_eff_ from z=1.5-4.
- ID:
- ivo://CDS.VizieR/J/ApJ/726/19
- Title:
- Intermediate-mass stars in IC 1805
- Short Name:
- J/ApJ/726/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of a study of the intermediate- and high-mass stars in the young, rich star-forming complex IC 1805, based on a combination of optical, near-infrared, and mid-infrared photometry, and classification spectra. These data provide the basis for characterizing the masses and ages for stars more massive than ~2M_{sun}_ and enable a study of the frequency and character of circumstellar disks associated with intermediate- and high-mass stars. Optically thick accretion disks among stars with masses 2<M/M_{sun}_<4 are rare (~2% of members) and absent among more massive stars. A larger fraction (~10%) of stars with masses 2<M/M_{sun}_<4 appear to be surrounded by disks that have evolved from the initial optically thick accretion phase. We identify four classes of such disks. These classes are based on spectral energy distributions (SEDs) of excess emission above photospheric levels: disks that are (1) optically thin based on the magnitude of the observed excess emission from 2 to 24um, (2) optically thin in their inner regions (r<20AU) and optically thick in their outer regions, (3) exhibit empty inner regions (r<10AU) and optically thin emission in their outer regions, and (4) exhibit empty inner regions and optically thick outer regions. We discuss, and assess the merits and liabilities of, proposed explanations for disks exhibiting these SED types and suggest additional observations that would test these proposals.
