Coordinates and identifications are presented for 726 Harvard Variable stars and suspected variables, discovered or studied by D. Hoffleit and announced in Harvard Bulletins 874, 884, 887, 901, and 902; plus 141 others, previously known, lying in the same fields.
Astrometry and photometry for 318 ultracool dwarfs in 265 systems that have measured trigonometric parallaxes. To be included in this tabulation, an object must have a spectral type >=M6 or a K-band absolute magnitude >8.5mag. Parallaxes, proper motions, and coordinates at a specified epoch are given for all objects. Photometric measurements in MKO, 2MASS, Spitzer, and WISE systems are given when available. Various other flags that provide additional information about the object or photometry are included.
of Paper: The Henry Draper Extension Charts (Cannon et al., 1949), published in the form of finding charts, provide spectral classification for some 87000 stars mostly between 10th and 11th magnitude. This data, being highly valuable, as yet was practically unusable for modern computer-based astronomy. An earlier pilot project (Roeser et al. 1991) demonstrated a possibility to convert this into a star catalogue, using measurements of cartesian coordinates of stars on the charts and positions of the Astrographic Catalogue (AC) for subsequent identification. We present here a final HDEC catalogue comprising accurate positions, proper motions, magnitudes and spectral classes for 86933 stars of the Henry Draper Extension Charts.
We have used high-cadence radial velocity measurements from the Hobby-Eberly Telescope with published velocities from the Lick 3 m Shane Telescope, combined with astrometric data from the Hubble Space Telescope (HST) Fine Guidance Sensors to refine the orbital parameters of the HD 128311 system, and determine an inclination of 55.95{deg}+/-14.55{deg} and true mass of 3.789_-0.432_^+0.924^ M_JUP_ for HD 128311 c. The combined radial velocity data also reveal a short period signal which could indicate a third planet in the system with an Msin i of 0.133+/-0.005 M_JUP_or stellar phenomena. Photometry from the T12 0.8 m automatic photometric telescope at the Fairborn Observatory and HST are used to determine a photometric period close to, but not within the errors of the radial velocity signal. We performed a cross-correlation bisector analysis of the radial velocity data to look for correlations with the photometric period and found none. Dynamical integrations of the proposed system show long-term stability with the new orbital parameters of over 10 million years. Our new orbital elements do not support the claims of HD 128311 b and c being in mean motion resonance.
Wide binaries are a potential pathway for the formation of hot Jupiters. The binary fraction among host stars is an important discriminator between competing formation theories, but has not been well characterised. Additionally, contaminating light from unresolved stars can significantly affect the accuracy of photometric and spectroscopic measurements in studies of transiting exoplanets. We observed 101 transiting exoplanet host systems in the Southern hemisphere in order to create a homogeneous catalogue of both bound companion stars and contaminating background stars, in an area of the sky where transiting exoplanetary systems have not been systematically searched for stellar companions. We investigate the binary fraction among the host stars in order to test theories for the formation of hot Jupiters. Lucky imaging observations from the Two Colour Instrument on the Danish 1.54m telescope at La Silla were used to search for previously unresolved stars at small angular separations. The separations and relative magnitudes of all detected stars were measured. For 12 candidate companions to 10 host stars, previous astrometric measurements were used to evaluate how likely the companions are to be physically associated. We provide measurements of 499 candidate companions within 20 arcseconds of our sample of 101 planet host stars. 51 candidates are located within 5 arcseconds of a host star, and we provide the first published measurements for 27 of these. Calibrations for the plate scale and colour performance of the Two Colour Instrument are presented. We find that the overall multiplicity rate of the host stars is 38+17%, consistent with the rate among solar-type stars in our sensitivity range, suggesting that planet formation does not preferentially occur in long period binaries compared to a random sample of field stars. Long period stellar companions (P>10yr) appear to occur independently of short period companions, and so the population of close-in stellar companions is unconstrained by our study.
Several galaxies were studied at Observatoire de Marseille using the films obtained at the 6m telescope with the Great Focal Reducer installed at the prime focus of the russian telescope. We thought that before we retire, it should be of some interest for the astronomical community to find in a single catalogue all the data we published to facilitate the research. (see hereunder the references). We give in this catalogue the data of the following galaxies: M 33, M 51, M 81, NGC 2403, NGC 4258 and NGC 7331. NGC 4258 was not studied with the 6m telescope, but we added its results because it was published by the same team using the same softwares. For NGC 7331 (see Petit 1998, Cat. J/A+AS/131/317). The flux values are followed by*; that means that they are not absolute fluxes like in the other publications. In order to make the catalogue easier to consult, we homogeneised the data. So, one can find some slight differences between the original data and the catalogue ones. The details of these modifications are precised in the Readme file associated to the catalogue in the data base. We did not keep the remarks so it is necessary to look at the original publication to find the full information. We give the whole references hereunder to facilitate the research of the original articles.
We present a new Halpha image of high quality of the grand-design galaxy NGC 6814, and describe statistical properties of the HII region population. We have determined positions, angular sizes, and calibrated fluxes of 735 individual HII regions. We construct luminosity functions (LFs) for the complete sample, separately for arm and interarm regions, and for HII regions within and outside the limiting radius corresponding to the bright optical disk. The slope of the LF for the complete sample agrees well with values published for other Sbc and Sc galaxies. LFs for HII regions in the arms, in the interarm regions, in the inner part, and in the outer part of the galaxy all have the same slopes. We show and discuss the diameter distribution of the HII regions, both for the complete sample and for the separate arm, interarm, inner, and outer disk samples. There is no evidence for a different population of HII regions in the spiral arms, nor is there evidence for the existence of a significant population of density-bounded HII regions. We discuss implications for massive star forming processes in this galaxy, and discuss possible differences from other grand-design spirals.
The main result catalog from the ESA Hipparcos satellite, obtained
November 1989 through March 1993. In the GAVO DC, several columns were
left out and all angles are given in degrees.
We present a cross-calibration of Hipparcos and Gaia EDR3 intended to identify astrometrically accelerating stars and to fit orbits to stars with faint, massive companions. The resulting catalog, the EDR3 edition of the Hipparcos-Gaia Catalog of Accelerations (HGCA), provides three proper motions with calibrated uncertainties on the EDR3 reference frame: the Hipparcos proper motion, the Gaia EDR3 proper motion, and the long-term proper motion given by the difference in position between Hipparcos and Gaia EDR3. Our approach is similar to that for the Gaia DR2 edition of the HGCA but offers a factor of ~3 improvement in precision thanks to the longer time baseline and improved data processing of Gaia EDR3. We again find that a 60/40 mixture of the two Hipparcos reductions outperforms either reduction individually, and we find strong evidence for locally variable frame rotations between all pairs of proper motion measurements. The substantial global frame rotation seen in DR2 proper motions has been removed in EDR3. We also correct for color- and magnitude-dependent frame rotations at a level of up to ~50{mu}as/yr in Gaia EDR3. We calibrate the Gaia EDR3 uncertainties using a sample of radial velocity standard stars without binary companions; we find an error inflation factor (a ratio of total to formal uncertainty) of 1.37. This is substantially lower than the position-dependent factor of ~1.7 found for Gaia DR2 and reflects the improved data processing in EDR3. While the catalog should be used with caution, its proper motion residuals provide a powerful tool to measure the masses and orbits of faint, massive companions to nearby stars.
The Hipparcos Input Catalogue was constructed as the observing program for ESA's Hipparcos astrometry mission. This has resulted in a catalogue of stellar data including up-to-date information on positions, proper motions, magnitudes, colors, and when available, spectral types, radial velocities, multiplicity and variability information. The catalogue is complete to well-defined magnitude limits, and includes a substantial sampling of the most important stellar categories present in the solar neighbourhood beyond these limits. The magnitude limits vary from 7.3 to 9 magnitudes as a function of galactic latitude and spectral type, and there are no stars fainter than about V = 13 mag. 118000 stars are included in the Hipparcos Input Catalogue, about half of them have been selected within well-defined limits in V magnitude, spectral type and galactic latitude (the "survey"), half of them within proposed observing programs. The mean accuracies achieved, as demonstrated by comparison with the Hipparcos results (Turon et al. 1995A&A...304...82T) are 0.3 arcsec for the positions and 0.25 mag for the Hp magnitude, with accuracies of 0.02 mag or better for more than a third of the catalogue. The data set consists of the main catalogue, and the first supplement which contains more detailed information for multiple system components. Other supplements with identification charts can be found in the published version. A complete description is provided, either as a LaTeX file (intro.tex), or as a plain ascii file (intro.cat).
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