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511. Southern Reference Star Catalogue
ID:
ivo://CDS.VizieR/I/138
Title:
Southern Reference Star Catalogue
Short Name:
I/138
Date:
21 Oct 2021
Publisher:
CDS
Description:
The positions are the combined results of observations of all participants in the Southern Reference Star (SRS) observing campaign from 1961 tO 1973. Preliminary catalogs were compiled at both the U.S. Naval Observatory (Washington) and the Pulkovo Observatory (Leningrad). The two compilations were compared, reconciled and combined to give the catalog described here. The proper motions have been culled from a number of different sources and should not be regarded as part of the SRS observed catalog. The proper motions are given principally as a means to take into account the small differences in epoch of observation between the SRS and the 2nd Cape Photographic Catalog plate material, which is at most about two years. Because of the inhomogeneous nature of the proper-motion sources and the likely presence of magnitude related systematic errors in the proper motions, they may not safely be used to extend the SRS system of positions very far from the mean epoch of observation which is about 1968. A discussion by T. Corbin of all the SRS observations including those made before and after the 1961 to 1973 campaign and their reduction to the FK4 system is at an advanced stage of preparation and will yield the desired high quality proper motions required for transferring the system to more distant epochs. Two sets of positions and proper motions are given. One set is referred to the equator and equinox of B1950.0 and the other to the equator and equinox of J2000.0. The positions are referred to the mean epoch of observation in both cases. The B1950.0 positions were linked directly to the system of FK4 by observational techniques. The J2000.0 data are based on a transformation of the B1950.0 data. The transformation was accomplished in two steps. First, FK5-FK4 differences referred to the B1950.0/FK4 system were added to the SRS positions and proper motions. The FK5-FK4 differences are those given by the analytical coefficients of H. Schwan (Astronomisches Rechen-Institut, Heidelberg). Second, the reduction from B1950.0 to J2000.0 was accomplished by using the conversion procedure described in the 1988 edition of THE ASTRONOMICAL ALMANAC (pg. B42). The (FK5-FK4) differences are given along with the average FK4 magnitude used as the input argument to Schwan's subroutines. An average FK4 magnitude was estimated for each SRS position from the average magnitude of all FK4 stars in an area on the celestial sphere bounded by a four-hour interval in right ascension and a 20-degree interval in declination centered on the SRS. All SRS less than 10 deg from the pole were treated as if they had been at -80 deg declination for the calculation of the average FK4 magnitude only. This transformation procedure gives a first order reduction from the FK4 to the FK5 system. A more precise reduction of many of the SRS catalogs observed from 1961 to 1973 is possible from a re-discussion of the FK4 star observations made concurrently with the SRS observations on a nightly basis. A program to reduce first the SRS and then the AGK3R to the FK5 system as directly as possible, going back to the nightly observations of FK4/FK5 when they are available, is now in progress at the observatory in Washington.
512. 5969 Southern Reference Stars and 726 Bright stars
ID:
ivo://CDS.VizieR/I/309
Title:
5969 Southern Reference Stars and 726 Bright stars
Short Name:
I/309
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue contains 5969 southern reference stars (SRS) and 726 bright stars (BS). The observations were carried out in the declination zone from 0{deg} to -20{deg} with the Repsold meridian circle in Nikolaev Astronomical Observatory (Ukraine) in 1964-1966. The RMS errors of right ascensions are 18ms and 25ms for the SRS and the BS correspondingly. The RMS errors of declinations are 480mas and 470mas for the SRS and the BS correspondingly. The catalogue is in good agreement with a system of the FK4.
513. Spatially offset AGN cand. in CLASS survey
ID:
ivo://CDS.VizieR/J/MNRAS/475/5179
Title:
Spatially offset AGN cand. in CLASS survey
Short Name:
J/MNRAS/475/5179
Date:
02 Nov 2021 11:24:39
Publisher:
CDS
Description:
Prompted by a recent claim by Barrows et al. that X-ray active galactic nuclei (AGNs) are often found significantly offset from the centres of their host galaxies, we have looked for examples of compact radio sources that are offset from the optical centroids of nearby (z<0.2) galaxies. We have selected a sample of 345 galaxies from the Sloan Digital Sky Survey (SDSS) galaxy catalogue, which have nearby compact radio sources listed in the Cosmic-Lens All Sky Survey (CLASS) catalogue. We find only three matches ~0.87 per cent of the sample) with offsets greater than 600 milliarcsec (mas), which is considerably fewer than we would have expected from the Barrows et al. X-ray survey. We fit our histogram of offsets with a Rayleigh distribution with {sigma}=60.5mas, but find that there is an excess of objects with separations greater than ~150mas. Assuming that this excess represents AGNs with real offsets, we place an upper limit of ~17 per cent on the fraction of offset AGNs in our radio-selected sample. We select 38 objects with offsets greater than 150mas, and find they have some diverse properties: Some are well known, such as Mrk 273 and Arp 220, some have dust lanes, which may have affected the optical astrometry, and a few are strong new candidates for offset AGNs.
514. Speckle interferometry at SOAR in 2020
ID:
ivo://CDS.VizieR/J/AJ/162/41
Title:
Speckle interferometry at SOAR in 2020
Short Name:
J/AJ/162/41
Date:
14 Mar 2022 06:54:42
Publisher:
CDS
Description:
The results of speckle interferometric observations at the 4.1m Southern Astrophysical Research Telescope in 2020, as well as earlier unpublished data, are given, totaling 1735 measurements of 1288 resolved pairs and nonresolutions of 1177 targets. We resolved for the first time 59 new pairs or subsystems in known binaries, mostly among nearby dwarf stars. This work continues our long-term speckle program. Its main goal is to monitor orbital motion of close binaries, including members of high-order hierarchies and Hipparcos pairs in the solar neighborhood. We also report observations of 892 members of young moving groups and associations, where we resolved 103 new pairs.
515. Speckle interferometry at the OAN-SPM Mexico
ID:
ivo://CDS.VizieR/J/AJ/161/253
Title:
Speckle interferometry at the OAN-SPM Mexico
Short Name:
J/AJ/161/253
Date:
09 Mar 2022
Publisher:
CDS
Description:
In this paper we present multiband speckle interferometric measurements of double stars performed at the 2.1m telescope of the Observatorio Astronomico Nacional, San Pedro Martir, Mexico. We focused our efforts on objects from the Washington Double Star Catalog that were observed during five runs allocated in 2018 and 2019. We report here 2101 astrometric and 2027 photometric measurements of 631 pairs, with angular separations ranging from 0.05" to 6.09", including 1622 measurements with separations smaller than 1", and a magnitude difference up to 5.99mag through the V filter, 5.46mag for the R filter, and 5.85mag for the I filter. We estimated a mean error in separation of 12mas, 1.1{deg} in position angle, and 0.14mag for the magnitude difference. We confirmed 58 double stars discovered by Hipparcos. For the first time we are presenting astrometric measurements for 7 systems listed at the Washington Double Star Catalog as being suspected binaries, which did not have a secondary confirmation, and 15 stars with only one published measurement. We identified a new close companion with a mean angular separation of 0.10", detected in a previously known pair. Finally, we present a correction to two previously published orbital solutions of two visual binaries.
516. Speckle interferometry at the USNO. XXIV.
ID:
ivo://CDS.VizieR/J/AJ/162/53
Title:
Speckle interferometry at the USNO. XXIV.
Short Name:
J/AJ/162/53
Date:
15 Mar 2022 08:28:18
Publisher:
CDS
Description:
The results of 3611 intensified CCD observations of double stars, made with the 26inch refractor of the U.S. Naval Observatory, are presented. Each observation of a system represents a combination of over 2000 short-exposure images. These observations are averaged into 1857 mean relative positions and range in separation from 0.341" to 128.644", with a median separation of 6.533". Two systems have their orbits improved and one has its first determination. This is the 24th in this series of papers and covers the period 2018 May 24 through 2019 October 28.
517. Speckle interferometry of Ap stars
ID:
ivo://CDS.VizieR/J/other/AstBu/67.44
Title:
Speckle interferometry of Ap stars
Short Name:
J/other/AstBu/67
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of speckle interferometry of a sample of 117 chemically peculiar stars with global magnetic fields. The observations were made in December 2009 at the BTA with a spatial resolution of about 0.02 arcseconds in the visual spectral region. Twenty-nine stars were resolved into individual components, 14 of them for the first time (HD965, HD5797, HD8855, HD10783, HD16605, HD21699, HD35502, HD51418, HD64486, HD79158, HD103498, HD108651, HD213918, HD293764). In twelve cases a companion turned out to be 2-4 magnitudes fainter than the main component - a magnetic star. Young hot Bp stars HD35502 and HD213918 are exceptions, since their companions are fainter by about 1 magnitude. In all cases, the linear distance from a star to its companion at the epoch of observations in the picture plane exceeded 10^9^km. Eighty-eight magnetic CP stars revealed no secondary components within our study. Thus, the fraction of speckle interferometric binaries in our sample amounts to 25%.
518. Speckle interferometry of Ap stars. II.
ID:
ivo://CDS.VizieR/J/other/AstBu/69.296
Title:
Speckle interferometry of Ap stars. II.
Short Name:
J/other/AstBu/69
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of speckle interferometric observations of 156 stars possessing global magnetic fields, carried out with the 6-m BTA telescope of the Special Astrophysical Observatory. Virtually all stars were observed between 2010 and 2012. Thirty-four stars were resolved into individual components (31 double and 3 triple), of which 14 binary systems (BD+41 43, HD2887, HD30466, HD36540, HD36955, HD37479, HD61045, HD89069, HD144334, HD164258, HD349321, HD343872, HD184471, HD196691) and 2 triple systems (HD37140, HD338226) were for the first time resolved by the astrometric method.
519. Speckle interferometry of HIP binaries
ID:
ivo://CDS.VizieR/J/AJ/121/3224
Title:
Speckle interferometry of HIP binaries
Short Name:
J/AJ/121/3224
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Hipparcos satellite made measurements of over 9734 known double stars, 3406 new double stars, and 11,687 unresolved but possible double stars. The high angular resolution afforded by speckle interferometry makes it an efficient means to confirm these systems from the ground, which were first discovered from space. Because of its coverage of a different region of angular separation-magnitude difference ({rho}-{Delta}m) space, speckle interferometry also holds promise to ascertain the duplicity of the unresolved Hipparcos "problem" stars. Presented are observations of 116 new Hipparcos double stars and 469 Hipparcos "problem stars," as well as 238 measures of other double stars and 246 other high-quality nondetections. Included in these are observations of double stars listed in the Tycho-2 Catalogue and possible grid stars for the Space Interferometry Mission.
520. Speckle interfero. nearby multiple stars. II
ID:
ivo://CDS.VizieR/J/AJ/162/156
Title:
Speckle interfero. nearby multiple stars. II
Short Name:
J/AJ/162/156
Date:
14 Mar 2022 06:50:24
Publisher:
CDS
Description:
Long-term monitoring at the 6m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences made it possible to improve the orbits of 15 objects (HIP689, HIP3951, HIP10438, HIP43948, HIP69962, HIP95995, HIP102029, HIP102357, HIP104383, HIP105947, HIP106255, HIP108917, HIP111546, HIP113726, HIP114922) and construct an orbital solution for HIP65327 for the first time. Observations have been carried out since 2007; that is, the accumulated data correspond to an interval of 13yr. As a result, most of the orbits were classified as "accurate" using the qualitative criteria by Worley & Heintz. A comparison of the mass sums and masses of the components calculated by two independent methods was made for objects with orbital solutions. The Gaia EDR3 parallax was used to obtain the fundamental parameters, as well as the Hipparcos and Gaia DR2 parallaxes.