- ID:
- ivo://CDS.VizieR/J/ApJ/879/105
- Title:
- Effective temperatures of low-mass stars
- Short Name:
- J/ApJ/879/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution, near-infrared spectra will be the primary tool for finding and characterizing Earth-like planets around low-mass stars. Yet, the properties of exoplanets cannot be precisely determined without accurate and precise measurements of the host star. Spectra obtained with the Immersion Grating Infrared Spectrometer simultaneously provide diagnostics for most stellar parameters, but the first step in any analysis is the determination of the effective temperature. Here we report the calibration of high-resolution H-band spectra to accurately determine the effective temperature for stars between 4000 and 3000K (~K8-M5) using absorption line-depths of FeI, OH, and Al I. The field star sample used here contains 254 K and M stars with temperatures derived using BT-Settl synthetic spectra. We use 106 stars with precise temperatures in the literature to calibrate our method, with typical errors of about 140K, and systematic uncertainties less than ~120K. For the broadest applicability, we present Teff-line-depth-ratio relationships, which we test on 12 members of the TW Hydrae Association and at spectral resolving powers between ~10000 and 120000. These ratios offer a simple but accurate measure of effective temperatures in cool stars that are distance and reddening independent.
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- ID:
- ivo://CDS.VizieR/J/AJ/156/292
- Title:
- Effect of close companions on exoplanetary radii
- Short Name:
- J/AJ/156/292
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Understanding the distribution and occurrence rate of small planets was a fundamental goal of the Kepler transiting exoplanet mission, and could be improved with K2 and Transiting Exoplanet Survey Satellite (TESS). Deriving accurate exoplanetary radii requires accurate measurements of the host star radii and the planetary transit depths, including accounting for any "third light" in the system due to nearby bound companions or background stars. High-resolution imaging of Kepler and K2 planet candidate hosts to detect very close (within ~0.5") background or bound stellar companions has been crucial for both confirming the planetary nature of candidates, and the determination of accurate planetary radii and mean densities. Here we present an investigation of the effect of close companions, both detected and undetected, on the observed (raw count) exoplanet radius distribution. We demonstrate that the recently detected "gap" in the observed radius distribution (also seen in the completeness-corrected distribution) is fairly robust to undetected stellar companions, given that all of the systems in the sample have undergone some kind of vetting with high-resolution imaging. However, while the gap in the observed sample is not erased or shifted, it is partially filled in after accounting for possible undetected stellar companions. These findings have implications for the most likely core composition, and thus formation location, of super-Earth and sub-Neptune planets. Furthermore, we show that without high-resolution imaging of planet candidate host stars, the shape of the observed exoplanet radius distribution will be incorrectly inferred, for both Kepler- and TESS-detected systems.
- ID:
- ivo://CDS.VizieR/J/AJ/156/83
- Title:
- Effect of stellar companions on planetary systems
- Short Name:
- J/AJ/156/83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Kepler light curves used to detect thousands of planetary candidates are susceptible to dilution due to blending with previously unknown nearby stars. With the automated laser adaptive optics instrument, Robo-AO, we have observed 620 nearby stars around 3857 planetary candidates host stars. Many of the nearby stars, however, are not bound to the KOI. We use galactic stellar models and the observed stellar density to estimate the number and properties of unbound stars. We estimate the spectral type and distance to 145 KOIs with nearby stars using multi-band observations from Robo-AO and Keck-AO. Most stars within 1" of a Kepler planetary candidate are likely bound, in agreement with past studies. We use likely bound stars and the precise stellar parameters from the California Kepler Survey to search for correlations between stellar binarity and planetary properties. No significant difference between the binarity fraction of single and multiple-planet systems is found, and planet hosting stars follow similar binarity trends as field stars, many of which likely host their own non-aligned planets. We find that hot Jupiters are ~4x more likely than other planets to reside in a binary star system. We correct the radius estimates of the planet candidates in characterized systems and find that for likely bound systems, the estimated planetary radii will increase on average by a factor of 1.77, if either star is equally likely to host the planet. Lastly, we find the planetary radius gap is robust to the impact of dilution.
- ID:
- ivo://CDS.VizieR/J/A+A/532/A74
- Title:
- EFIGI catalogue of 4458 nearby galaxies
- Short Name:
- J/A+A/532/A74
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Now that large databases of resolved galaxy images are provided by modern imaging surveys, advanced morphological studies can be envisioned, urging for well defined calibration samples. We present the EFIGI catalogue, a multiwavelength database specifically designed for a dense sampling of all Hubble types. The catalogue merges data from standard surveys and catalogues (Principal Galaxy Catalogue, Sloan Digital Sky Survey, Value-Added Galaxy Catalogue, HyperLeda, and the NASA Extragalactic Database) and provides detailed morphological information. Imaging data are obtained from the SDSS DR4 release in the u, g, r, i, and z bands for a sample of 4458 PGC galaxies, whereas photometric and spectroscopic data are obtained from the SDSS DR5 catalogue. Point-Spread Function models are derived in all five bands. Composite colour images of all objects are visually examined by a group of astronomers, and galaxies are staged along the Hubble sequence and classified according to 16 morphological attributes describing their structure, texture, as well as environment and appearance on a five-level scale. The EFIGI Hubble sequence shows remarkable agreement with the RC3 Revised Hubble Sequence. The main characteristics and reliability of the catalogue are examined, including photometric completeness, type mix, systematic trends and correlations. The final EFIGI database is a large sub-sample of the local Universe, with a dense sampling of Sd, Sdm, Sm and Im types compared to magnitude-limited catalogues. We estimate the photometric catalogue to be more than ~80% complete for galaxies with 10<g<14. More than 99.5% of EFIGI galaxies have a known redshift in the HyperLeda and NED databases.
- ID:
- ivo://CDS.VizieR/J/ApJ/657/706
- Title:
- EGRET blazar gamma-ray spectrum
- Short Name:
- J/ApJ/657/706
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory (CGRO) discovered gamma-ray emission from more than 67 blazars during its 9yr lifetime. We conducted an exhaustive search of the EGRET archives and selected all the blazars that were observed multiple times and were bright enough to enable a spectral analysis using standard power-law models. The sample consists of 18 flat-spectrum radio quasars (FSRQs), 6 low-frequency peaked BL Lac objects (LBLs) and 2 high-frequency peaked BL Lac objects (HBLs). We do not detect any clear pattern in the variation of spectral index with flux. Some of the blazars do not show any statistical evidence for spectral variability.
4086. EGRET blazars in VIPS
- ID:
- ivo://CDS.VizieR/J/ApJ/671/1355
- Title:
- EGRET blazars in VIPS
- Short Name:
- J/ApJ/671/1355
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the radio properties of EGRET-detected blazars observed as part of the VLBA Imaging and Polarimetry Survey (VIPS). VIPS has a flux limit roughly an order of magnitude below the MOJAVE survey and most other samples that have been used to study the properties of EGRET blazars. At lower flux levels, radio flux density does not directly correlate with gamma-ray flux density. We do find that the EGRET-detected blazars tend to have higher brightness temperatures, greater core fractions, and possibly larger than average jet opening angles. A weak correlation is also found with jet length and with polarization. All of the well-established trends can be explained by systematically larger Doppler factors in the gamma-ray-loud blazars, consistent with the measurements of higher apparent velocities found in monitoring programs carried out at radio frequencies above 10 GHz.
- ID:
- ivo://CDS.VizieR/J/ApJS/157/324
- Title:
- EGRET high-energy cosmic photons (E>10GeV)
- Short Name:
- J/ApJS/157/324
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During its 9 year lifetime, the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO) detected 1506 cosmic photons with measured energy E>10GeV. Of this number, 187 are found within a 1{deg} of sources that are listed in the Third EGRET Catalog (Cat. <J/ApJS/123/79>) and were included in determining the detection likelihood, flux, and spectra of those sources. In particular, five detected EGRET pulsars are found to have events above 10GeV, and together they account for 37 events. A pulsar not included in the Third EGRET Catalog has two events, both with the same phase and in one peak of the lower energy gamma-ray light curve.
- ID:
- ivo://irsa.ipac/Herschel/Catalog/eHOPS/eHOPSAquilaPhot
- Title:
- eHOPS Aquila SED Data Catalog
- Short Name:
- eHOPSAquilaPhot
- Date:
- 01 Apr 2023 01:07:05
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The Extension of HOPS Out to 500 ParSecs (eHOPS) project used archival data to survey all the major star forming molecular clouds within 500 pc of the Sun, except Orion (which was surveyed by HOPS). The first eHOPS data release covers the Aquila molecular clouds (d ~ 436 pc). For every source detected in the Herschel/PACS bands, the eHOPS-Aquila catalog contains 1-850 micron SEDs assembled from 2MASS, Spitzer, Herschel, WISE, and JCMT/SCUBA-2 data. A total of 172 protostars are found in Aquila, tightly concentrated in the molecular filaments that thread the clouds. Of these, 72 (42%) are Class 0 protostars, 53 (31%) Class I protostars, 43 (25%) are flat-spectrum protostars, and 4 (2%) are Class II sources. Ten of the Class 0 protostars are young PACS Bright Red Sources similar to those discovered in Orion. eHOPS compares the SEDs to a grid of radiative transfer models to constrain the luminosities, envelope densities, and envelope masses of the protostars.
- ID:
- ivo://irsa.ipac/Herschel/Catalog/eHOPS/eHOPSAquilaFits
- Title:
- eHOPS Aquila SED Fits Catalog
- Short Name:
- eHOPSAquilaFits
- Date:
- 01 Apr 2023 01:07:05
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The Extension of HOPS Out to 500 ParSecs (eHOPS) project used archival data to survey all the major star forming molecular clouds within 500 pc of the Sun, except Orion (which was surveyed by HOPS). The first eHOPS data release covers the Aquila molecular clouds (d ~ 436 pc). For every source detected in the Herschel/PACS bands, the eHOPS-Aquila catalog contains 1-850 micron SEDs assembled from 2MASS, Spitzer, Herschel, WISE, and JCMT/SCUBA-2 data. A total of 172 protostars are found in Aquila, tightly concentrated in the molecular filaments that thread the clouds. Of these, 72 (42%) are Class 0 protostars, 53 (31%) Class I protostars, 43 (25%) are flat-spectrum protostars, and 4 (2%) are Class II sources. Ten of the Class 0 protostars are young PACS Bright Red Sources similar to those discovered in Orion. eHOPS compares the SEDs to a grid of radiative transfer models to constrain the luminosities, envelope densities, and envelope masses of the protostars.
- ID:
- ivo://CDS.VizieR/V/64
- Title:
- Eighth Orbital Elements of Spectroscopic Binaries
- Short Name:
- V/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The complete description of the catalogue, as well as the notes, is to be found in the Publ. Dominion Astrophys. Obs. 17 (1989). The present machine-readable version was transformed from the file provided by A.H. Batten for easier computer readability. Compared to the printed version, please note the following: 1) The four columns No. f(m) m.sin^3(i) a.sin(i) are NOT included in the computer version. No. (running number) is the line number of the main file (from 1 to 1469) f(m) (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(1)**3 * P a(*)sin i (expressed in km) can be computed from the Fortran formula 13751 * sqrt(1-e*e) * K(*) * P m(*)sin3i (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(*) * (K(1)+K(2))**2 * P The parameters are K(*) = velocity amplitude of the components, expressed in km/s; P = Period, expressed in days, sometimes in years; e = eccentricity 2) The notes, which make the bulk of the printed catalogue (pages 129-304), are NOT included.