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541. Stellar stream in Gaia DR2 discovery
ID:
ivo://CDS.VizieR/J/A+A/622/L13
Title:
Stellar stream in Gaia DR2 discovery
Short Name:
J/A+A/622/L13
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of a large, dynamically cold, coeval stellar stream that is currently traversing the immediate solar neighborhood at a distance of only 100pc. The structure was identified in a wavelet decomposition of the 3D velocity space of all stars within 300pc of the Sun. Its members form a highly elongated structure with a length of at least 400pc, while its vertical extent measures only about 50pc. Stars in the stream are not isotropically distributed but instead form two parallel lanes with individual local overdensities, that may correspond to a remnant core of a tidally disrupted cluster or OB association. Its members follow a very well-defined main sequence in the observational Hertzsprung-Russel diagram and also show a remarkably low 3D velocity dispersion of only 1.3km/s. These findings strongly suggest a common origin as a single coeval stellar population. An extrapolation of the present-day mass function indicates a total mass of at least 2000M_{sun}_, making it larger than most currently known clusters or associations in the solar neighborhood. We estimated the age of the stream to be around 1 Gyr based on a comparison with a set of isochrones and giant stars in our member selection and find a mean metallicity of [Fe/H]=-0.04. This structure may very well represent the Galactic disk counterpart to the prominent stellar streams observed in the Milky Way halo. As such, it constitutes a new valuable probe to constrain the Galaxy's mass distribution.
542. Stroemgren-Crawford uvby{beta} photometry catalog
ID:
ivo://CDS.VizieR/J/A+A/580/A23
Title:
Stroemgren-Crawford uvby{beta} photometry catalog
Short Name:
J/A+A/580/A23
Date:
08 Nov 2021 15:39:26
Publisher:
CDS
Description:
The uvby{beta} photometric system is widely used for the study of various Galactic and extragalactic objects. It measures the colour due to temperature differences, the Balmer discontinuity, and blanketing absorption due to metals. A new all-sky catalogue of all available uvby{beta} measurements from the literature was generated. The data for the individual stars were cross-checked on the basis of the Tycho-2 catalogue.
543. Study of the COSC Korean astronomical catalogue
ID:
ivo://CDS.VizieR/J/MNRAS/454/1086
Title:
Study of the COSC Korean astronomical catalogue
Short Name:
J/MNRAS/454/1086
Date:
21 Oct 2021
Publisher:
CDS
Description:
The study of old star catalogues provides important astrometric data. Most of the researches based on the old star catalogues were manuscript published in Europe and from Arabic/Islam. However, the old star catalogues published in East Asia did not get attention. Therefore, among the East Asian star catalogues we focus on a particular catalogue recorded in a Korean almanac. Its catalogue contains 277 stars that are positioned in a region within 10{deg} of the ecliptic plane. The stars in the catalogue were identified using the modern Hipparcos catalogue (Cat. I/239). We identified 274 among 277 stars, which is a rate of 98.9 percent. The catalogue records the epoch of the stars' positions as AD 1396.0. However, by using all of the identified stars we found that the initial epoch of the catalogue is AD 1363.1+/-3.2. In conclusion, the star catalogue was compiled and edited from various older star catalogues. We assume a correlation with the Almagest by Ptolemaios. This study presents newly analysed results from the historically important astronomical data discovered in East Asia. Therefore, this star catalogue will become important data for comparison with the star catalogues published in Europe and from Arabic/Islam.
544. Supergalactic plane redshift survey
ID:
ivo://CDS.VizieR/J/ApJS/75/241
Title:
Supergalactic plane redshift survey
Short Name:
J/ApJS/75/241
Date:
21 Oct 2021
Publisher:
CDS
Description:
Redshift measurements, about 1000 of which are new, are presented for 1314 galaxies in a survey toward the apex of the large-scale streaming flow for ellipticals.
545. Supernovae and their hosts in the SDSS DR8
ID:
ivo://CDS.VizieR/J/A+A/544/A81
Title:
Supernovae and their hosts in the SDSS DR8
Short Name:
J/A+A/544/A81
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the creation of large and well-defined database that combines extensive new measurements and a literature search of 3876 supernovae (SNe) and their 3679 host galaxies located in the sky area covered by the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). This database should be much larger than previous ones, and should contain a homogenous set of global parameters of SN hosts, including morphological classifications and measures of nuclear activity. Identification of the host galaxy sample is 91% complete (with 3536 SNe in 3340 hosts), of which the SDSS names of ~1100 anonymous hosts are listed for the first time. The morphological classification is available for 2104 host galaxies, including 73 (56) hosts in interacting (merging) systems. The total sample of host galaxies collects heliocentric redshifts for 3317 (~90%) galaxies. The g-band magnitudes, D_25_, b/a, and PA are available for 2030 hosts of the morphologically classified sample of galaxies. Nuclear activity measures are provided for 1189 host galaxies. We analyze and discuss many selection effects and biases that can significantly affect any future analysis of our sample. The creation of this large database will help to better understand how the different types of SNe are correlated with the properties of the nuclei and global physical parameters of the host galaxies, and minimize possible selection effects and errors that often arise when data are selected from different sources and catalogues.
546. SuperWASP transit false positive catalog
ID:
ivo://CDS.VizieR/J/MNRAS/488/4905
Title:
SuperWASP transit false positive catalog
Short Name:
J/MNRAS/488/4905
Date:
21 Oct 2021
Publisher:
CDS
Description:
SuperWASP, the Northern hemisphere WASP observatory, has been observing the skies from La Palma since 2004. In that time, more than 50 planets have been discovered with data contributions from SuperWASP. In the process of validating planets, many false-positive candidates have also been identified. The TESS telescope is set to begin observations of the northern sky in 2019. Similar to the WASP survey, the TESS pixel size is relatively large (13 arcsec for WASP and 21 arcsec for TESS), making it susceptible to many blended signals and false detections caused principally by grazing and blended stellar eclipsing binary systems. In order to reduce duplication of effort on targets, we present a catalogue of 1041 Northern hemisphere SuperWASP targets that have been rejected as planetary transits through follow-up observation.
547. Survey of Centaurus A's Baryonic Structures II.
ID:
ivo://CDS.VizieR/J/MNRAS/469/3444
Title:
Survey of Centaurus A's Baryonic Structures II.
Short Name:
J/MNRAS/469/3444
Date:
21 Oct 2021
Publisher:
CDS
Description:
New wide-field u'g'r'i'z' Dark Energy Camera observations centred on the nearby giant elliptical galaxy NGC 5128 covering ~21 deg^2^ are used to compile a new catalogue of ~3200 globular clusters (GCs). We report 2404 newly identified candidates, including the vast majority within ~140kpc of NGC 5128. We find evidence for a transition at a galactocentric radius of R_gc_~=55kpc from GCs 'intrinsic' to NGC 5128 to those likely to have been accreted from dwarf galaxies or that may transition to the intragroup medium of the Centaurus A galaxy group. We fit power-law surface number density profiles of the form {Sigma}_N,R_gc_{prop.to}R_gc_^{Gamma}^ and find that inside the transition radius, the red GCs are more centrally concentrated than the blue, with {Gamma}_inner,red_~=-1.78 and {Gamma}_inner,blue_~=-1.40, respectively. Outside this region both profiles flatten, more dramatically for the red GCs ({Gamma}_outer,red_~=-0.33) compared to the blue ({Gamma}_outer,blue_~= -0.61), although the former is more likely to suffer contamination by background sources. The median (g'-z')_0_=1.27mag colour of the inner red population is consistent with arising from the amalgamation of two giant galaxies each less luminous than present-day NGC 5128. Both inwards and outwards of the transition radius, we find the fraction of blue GCs to dominate over the red GCs, indicating a lively history of minor mergers. Assuming the blue GCs to originate primarily in dwarf galaxies, we model the population required to explain them, while remaining consistent with NGC 5128's present-day spheroid luminosity. We find that several dozen dwarfs of luminosities L_dw,V_~= 10^6-9.3^L_V,{sun}_, following a Schechter luminosity function with a faint-end slope of -1.50<={alpha}<=-1.25 is favoured, many of which may have already been disrupted in NGC 5128's tidal field.
548. Survey of faint compact objects
ID:
ivo://CDS.VizieR/J/MNRAS/253/686
Title:
Survey of faint compact objects
Short Name:
J/MNRAS/253/686
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a low-resolution (73A) spectroscopic survey of faint compact objects conducted with the Low Dispersion Survey Spectrograph at the Anglo-Australian Telescope. The sample is a random subset of all compact sources with 22.5<=b_j_<=23.5 in three high-latitude fields. Additional data on compact sources with 21<=b_j_<=22.5 have been selected from the higher resolution (13A) survey previously published by Colless et al. (1990), and a subset of these brighter objects has been studied at both dispersions.
549. Sydney Southern Star Catalogue
ID:
ivo://CDS.VizieR/I/86A
Title:
Sydney Southern Star Catalogue
Short Name:
I/86A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue principally covers the range between -51deg. and -63.5 deg and contains positions and proper motions for 29,926 stars. 3244 faint Astrographic stars were added to supplement the stars at fainter magnitudes. Positions in standard form (hours, minutes, and seconds of time for the right ascensions and degrees, minutes, and seconds of arc for the declinations) have been added to the machine readable version of this catalogue.
550. tau Boo Radial velocities & astrometric data
ID:
ivo://CDS.VizieR/J/A+A/625/A59
Title:
tau Boo Radial velocities & astrometric data
Short Name:
J/A+A/625/A59
Date:
21 Oct 2021
Publisher:
CDS
Description:
The formation of planets in compact or highly eccentric binaries and the migration of hot Jupiters are two outstanding problems in planet formation. Detailed characterisation of known systems is important for informing and testing models. The hot Jupiter {tau} Boo Ab orbits the primary star in the long-period (P>~1000yr), highly eccentric (e~0.9) double star system {tau} Bootis. Due to the long orbital period, the orbit of the stellar binary is poorly constrained. Here we aim to constrain the orbit of the stellar binary {tau} Boo AB in order to investigate the formation and migration history of the system. The mutual orbital inclination of the stellar companion and the hot Jupiter has important implications for planet migration. The binary eccentricity and periastron distance are important for understanding the conditions under which {tau} Boo formed. We combine more than 150 years of astrometric data with twenty-five years of high-precision radial velocities. The combination of sky-projected and line-of-sight measurements places tight constraints on the orbital inclination, eccentricity, and periastron distance of {tau} Boo AB. We determine the orbit of {tau} Boo B and find an orbital inclination of 47.2^+2.7^_-3.7_{deg}, a periastron distance of 28.3^+2.3^_-3.0_au, and an eccentricity of 0.87^+0.04^_-0.03_. We find that the orbital inclinations of {tau} Boo Ab and {tau} Boo B, as well as the stellar spin-axis of {tau} Boo A coincide at ~45 degrees, a result consistent with the assumption of a well-aligned, coplanar system. The likely aligned, coplanar configuration suggests planetary migration within a well-aligned protoplanetary disc. Due to the high eccentricity and small periastron distance of {tau} Boo B, the protoplanetary disc was tidally truncated at ~6au. We suggest that {tau} Boo Ab formed near the edge of the truncated disc and migrated inwards with high eccentricity due to spiral waves generated by the stellar companion.