- ID:
- ivo://CDS.VizieR/VI/125
- Title:
- Theoretical spectra of red giants and supergiants
- Short Name:
- VI/125
- Date:
- 10 Mar 2022
- Publisher:
- CDS
- Description:
- It remains difficult to interpret the near-IR emission of young stellar populations. One main reason is our incomplete understanding of the spectra of luminous red stars. This work provides a grid of theoretical spectra of red giant (RG) and red supergiant (RSG) stars, that extends through optical and near-IR wavelengths. For the first time, models are also provided with modified surface abundances of C, N and O, as a step towards accounting for the changes that occur due to convective dredge-up in red supergiants or may occur at earlier evolutionary stages in the case of rotation. The aims are (i) to assess how well current models reproduce observed spectra, in particular in the near-IR; (ii) to quantify the effects of the abundance changes on the spectra; and (iii) to determine how these changes affect estimates of fundamental stellar parameters.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/896/77
- Title:
- The PHLEK survey: oxygen & helium abundances
- Short Name:
- J/ApJ/896/77
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We present Keck NIRSPEC and Keck NIRES spectroscopy of sixteen metal-poor galaxies that have pre-existing optical observations. The near-infrared (NIR) spectroscopy specifically targets the HeI{lambda}10830{AA} emission line, due to its sensitivity to the physical conditions of the gas in HII regions. We use these NIR observations, combined with optical spectroscopy, to determine the helium abundance of sixteen galaxies across a metallicity range 12+log_10_(O/H)=7.13-8.00. This data set is combined with two other samples where metallicity and helium abundance measurements can be secured: star-forming galaxies selected from the Sloan Digital Sky Survey spectroscopic database, and existing low-metallicity systems in the literature. We calculate a linear fit to these measurements, accounting for intrinsic scatter, and report a new determination of the primordial helium number abundance, y_P_=0.0805_-0.0017_^+0.0017^, which corresponds to a primordial helium mass fraction Y_P_=0.2436_-0.0040_^+0.0039^. Using our determination of the primordial helium abundance in combination with the latest primordial deuterium measurement, (D/H)_P_x10^5^=2.527+/-0.030, we place a bound on the baryon density {Omega}_b_h^2^=0.0215_-0.0005_^+0.0005^ and the effective number of neutrino species N_eff_=2.85_-0.25_^+0.28^. These values are in 1.3{sigma} agreement with those deduced from the Planck satellite observations of the temperature fluctuations imprinted on the cosmic microwave background.
- ID:
- ivo://CDS.VizieR/J/ApJ/822/93
- Title:
- The population of compact radio sources in ONC
- Short Name:
- J/ApJ/822/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a deep centimeter-wavelength catalog of the Orion Nebula Cluster (ONC), based on a 30hr single-pointing observation with the Karl G. Jansky Very Large Array in its high-resolution A-configuration using two 1GHz bands centered at 4.7 and 7.3GHz. A total of 556 compact sources were detected in a map with a nominal rms noise of 3{mu}Jy/bm, limited by complex source structure and the primary beam response. Compared to previous catalogs, our detections increase the sample of known compact radio sources in the ONC by more than a factor of seven. The new data show complex emission on a wide range of spatial scales. Following a preliminary correction for the wideband primary-beam response, we determine radio spectral indices for 170 sources whose index uncertainties are less than +/-0.5. We compare the radio to the X-ray and near-infrared point-source populations, noting similarities and differences.
- ID:
- ivo://CDS.VizieR/J/ApJS/208/11
- Title:
- The Red MSX Source Survey: massive protostars
- Short Name:
- J/ApJS/208/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Red MSX Source survey, the largest statistically selected catalog of young massive protostars and H II regions to date. We outline the construction of the catalog using mid- and near-infrared color selection. We also discuss the detailed follow up work at other wavelengths, including higher spatial resolution data in the infrared. We show that within the adopted selection bounds we are more than 90% complete for the massive protostellar population, with a positional accuracy of the exciting source of better than 2 arcsec. We briefly summarize some of the results that can be obtained from studying the properties of the objects in the catalog as a whole; we find evidence that the most massive stars form: (1) preferentially nearer the Galactic center than the anti-center; (2) in the most heavily reddened environments, suggestive of high accretion rates; and (3) from the most massive cloud cores.
- ID:
- ivo://CDS.VizieR/II/94
- Title:
- The Revised AFGL (RAFGL) Catalogue
- Short Name:
- II/94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog (RAFGL) contains the results of extensive verification and photometric studies of AFGL sources performed since the publication of "The AFGL Four Color Infrared Sky Survey: Catalog of Observations at 4.2, 11.0, 19.8, and 27.4 micrometers" (AFGL, Price and Walker 1976) as well as recent survey measurements with larger instruments. Improved positions and more extensive photometry have been provided by ground-based searches for the RAFGL objects and questions about unconfirmed sources from early investigations of the AFCRL Infrared Sky Survey (Walker and Price 1975) have, for the most part, been resolved. Many of the spurious sources were eliminated from the AFGL catalog in the reanalysis by including a rescan confirmation criterion in addition to the signal-to-noise gate used for the AFCRL catalog. The RAFGL is a revision of AFGL to include more accurate information and to provide identifications and improved positions for unidentified AFGL sources.
- ID:
- ivo://CDS.VizieR/J/AJ/161/233
- Title:
- The revised TESS habitable zone catalog
- Short Name:
- J/AJ/161/233
- Date:
- 20 Jan 2022
- Publisher:
- CDS
- Description:
- In the search for life in the cosmos, NASA's Transiting Exoplanet Survey Satellite (TESS) mission has already monitored about 74% of the sky for transiting extrasolar planets, including potentially habitable worlds. However, TESS only observed a fraction of the stars long enough to be able to find planets like Earth. We use the primary mission data-the first two years of observations-and identify 4239 stars within 210pc that TESS observed long enough to see three transits of an exoplanet that receives similar irradiation to Earth: 738 of these stars are located within 30pc. We provide reliable stellar parameters from the TESS Input Catalog that incorporates Gaia DR2 and also calculate the transit depth and radial velocity semiamplitude for an Earth-analog planet. Of the 4239 stars in the Revised TESS HZ Catalog, 9 are known exoplanet hosts-GJ1061, GJ1132, GJ3512, GJ685, Kepler-42, LHS1815, L98-59, RRCae, and TOI700-around which TESS could identify additional Earth-like planetary companions. Thirty-seven additional stars host yet unconfirmed TESS Objects of Interest: three of these orbit in the habitable-zone TOI203, TOI715, and TOI2298. For a subset of 614 of the 4239 stars, TESS has observed the star long enough to be able to observe planets throughout the full temperate, habitable zone out to the equivalent of Mars orbit. Thus, the Revised TESS Habitable Zone Catalog provides a tool for observers to prioritize stars for follow-up observation to discover life in the cosmos. These stars are the best path toward the discovery of habitable planets using the TESS mission data.
- ID:
- ivo://CDS.VizieR/J/A+A/507/795
- Title:
- The RMS survey: water masers of YSOs
- Short Name:
- J/A+A/507/795
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The red MSX source (RMS) survey has identified a large sample of candidate massive young stellar objects (MYSOs) and ultra compact (UC) HII regions from a sample of ~2000 MSX and 2MASS colour selected sources. To search for H_2_O masers towards a large sample of young high mass stars and to investigate the statistical correlation of H_2_O masers with the earliest stages of massive star formation. We have used the Mopra Radio telescope to make position-switched observations towards ~500 UCHII regions and MYSOs candidates identified from the RMS survey and located between 190{deg}<l<30{deg}. These observations have a 4{sigma} sensitivity of ~1Jy and a velocity resolution of ~0.4km/s.
- ID:
- ivo://CDS.VizieR/J/AJ/161/172
- Title:
- The Solar Neighborhood. XLVII. Mdwarfs with STIS
- Short Name:
- J/AJ/161/172
- Date:
- 18 Jan 2022
- Publisher:
- CDS
- Description:
- We use HST/STIS optical spectroscopy of 10 M-dwarfs in five closely separated binary systems to test models of M-dwarf structure and evolution. Individual dynamical masses ranging from 0.083 to 0.405M{sun} for all stars are known from previous work. We first derive temperature, radius, luminosity, surface gravity, and metallicity by fitting the BT-Settl atmospheric models. We verify that our methodology agrees with empirical results from long-baseline optical interferometry for stars of similar spectral types. We then test whether or not evolutionary models can predict those quantities given the stars' known dynamical masses and the conditions of coevality and equal metallicity within each binary system. We apply this test to five different evolutionary model sets: the Dartmouth models, the MESA/MIST models, the models of Baraffe et al., the PARSEC models, and the YaPSI models. We find marginal agreement between evolutionary model predictions and observations, with few cases where the models respect the condition of coevality in a self-consistent manner. We discuss the pros and cons of each family of models and compare their predictive power.
- ID:
- ivo://CDS.VizieR/J/ApJ/693/1821
- Title:
- The Spitzer infrared nearby galaxies survey
- Short Name:
- J/ApJ/693/1821
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution mid-infrared spectra are presented for 155 nuclear and extranuclear regions from the Spitzer Infrared Nearby Galaxies Survey (SINGS). The fluxes for nine atomic forbidden and three molecular hydrogen mid-infrared emission lines are also provided, along with upper limits in key lines for infrared-faint targets. The SINGS sample shows a wide range in the ratio of [SIII]18.71um/[SIII]33.48um, but the average ratio of the ensemble indicates a typical interstellar electron density of 300-400cm^-3^ on ~23x15" scales and 500-600cm^-3^ using ~11x9" apertures, independent of whether the region probed is a star-forming nuclear, a star-forming extranuclear, or an active galactic nuclei (AGN) environment.
- ID:
- ivo://CDS.VizieR/J/ApJ/741/79
- Title:
- The Spitzer-SDSS-GALEX Spectroscopic Survey
- Short Name:
- J/ApJ/741/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer-SDSS-GALEX Spectroscopic Survey (SSGSS) provides a new sample of 101 star-forming galaxies at z<0.2 with unprecedented multi-wavelength coverage. New mid- to far-infrared spectroscopy from the Spitzer Space Telescope is added to a rich suite of previous imaging and spectroscopy, including ROSAT, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, and Spitzer/SWIRE. Sample selection ensures an even coverage of the full range of normal galaxy properties, spanning two orders of magnitude in stellar mass, color, and dust attenuation. In this paper we present the SSGSS data set, describe the science drivers, and detail the sample selection, observations, data reduction, and quality assessment.
