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81. Binary Star Pop. with Common Proper Motion
ID:
ivo://CDS.VizieR/J/AZh/97/733
Title:
Binary Star Pop. with Common Proper Motion
Short Name:
J/AZh/97/733
Date:
22 Feb 2022
Publisher:
CDS
Description:
We describe a homogeneous catalog compilation of common proper motion stars based on GaiaDR2. A preliminary list of all pairs of stars within the radius of 100pc around the Sun with a separation less than a parsec was compiled. Also, a subset of comoving pairs, wide binary stars, was selected. The clusters and systems with multiplicity larger than 2 were excluded from consideration. The resulting catalog contains 10358 pairs of stars. The catalog selectivity function was estimated by comparison with a set of randomly selected field stars and with a model sample obtained by population synthesis. The estimates of the star masses in the catalogued objects, both components of which belong to the main-sequence, show an excess of ''twins'', composed by stars with similar masses. This excess decreases with increasing separation between components. It is shown that such an effect cannot be a consequence of the selectivity function only and does not appear in the model where star formation of similar masses is not artificially preferred. The article is based on the talk presented at the conference ''Astrometry yesterday, today, tomorrow'' (Sternberg Astronomical Institute of the Moscow State University, October 14 - 16, 2019).
82. Blue stragglers and variable stars in M3
ID:
ivo://CDS.VizieR/J/AJ/108/1786
Title:
Blue stragglers and variable stars in M3
Short Name:
J/AJ/108/1786
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper describes Hubble Space Telescope (HST)/Planetary Camera-I images of the core of the dense globular cluster M3 (NGC 5272). Stellar photometry in the F555W (V) and F785LP (I) bands, with a 1 sigma photometric accuracy of about 0.1mag, has been used to construct color-magnitude diagrams of about 4700 stars above the main-sequence turnoff within r<~1' of the cluster center. We have also analyzed archival HST F336W (U) images of M3 obtained by the Wide Field/Planetary Camera-I Instrument Definition Team. The UVI data are used to identify 28 blue straggler (BS) stars within the central 0.29arcmin^2. The specific frequency of BSs in this region of M3, N(BS)/N(V<V(HB)+2)=0.094+/-0.019, is about a factor of 2-3 higher than that found by Bolte et al. [1993, ApJ, 408, L89] in a recent ground-based study of the same region, but comparable to that seen in the sparse outer parts of the same cluster and in HST observations of the core of the higher density cluster 47 Tuc. The BSs in M3 are slightly more centrally concentrated than red giant branch stars while horizontal branch stars are somewhat less concentrated than red giants. The radial distribution of V-selected subgiant and turnoff stars is well fit by a King model with a core radius r(core)=28"+/-2" (90% confidence limits), which corresponds to 1.4pc. Red giant and horizontal branch stars selected in the ultraviolet data (U<18) have a somewhat more compact distribution (r(core)=22.5"). The HST U data consist of 17 exposures acquired over a span of three days. We have used these data to isolate 40 variable stars for which relative astrometry, brightnesses, colors, and light curves are presented. A Kolmogorov-Smirnov test indicates that, typically, the variability for each star is significant at the 95% level. We identify two variable BS candidates (probably of the SX Phe type) out of a sample of ~25 BSs in which variability could have been detected. Most of the variables are RR Lyrae stars on the horizontal branch. All of them have periods P>~8h.
83. Bordeaux AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/228
Title:
Bordeaux AC Zone Data Reduced to ACRS
Short Name:
I/228
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Bordeaux Zone, whose plates are centered between declinations +11 and +17 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 223,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
84. Bright Stars Supplement to PPM
ID:
ivo://CDS.VizieR/I/206
Title:
Bright Stars Supplement to PPM
Short Name:
I/206
Date:
21 Oct 2021
Publisher:
CDS
Description:
A number of bright stars is missing from the PPM Star Catalogue, both on the northern <I/146> and on the southern <I/193> hemisphere. The Bright Stars Supplement described here makes PPM complete down to V=7.5 mag. For this purpose it lists all missing stars brighter than V=7.6 mag that we could find in published star lists. Their total number is 275. Only 2 of them are brighter than V=3.5. This replaces the December 1992 edition (catalogue I/194) of the Bright Stars Supplement which inadvertently contained 46 duplicates of stars already contained in the main parts of PPM.
85. Brorfelde Meridian Catalogues 1964-1976
ID:
ivo://CDS.VizieR/I/99
Title:
Brorfelde Meridian Catalogues 1964-1976
Short Name:
I/99
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains positions and magnitudes for 1577 stars with visual magnitudes brighter than 11.0. The observations were made with the 7-inch transit circle at the Copenhagen University Observatory from July 1981 to May 1982. The positions are reduced to the FK4 system for each night and over the whole meridian. The mean errors of the catalog entries are: in right ascension 0.006 seconds/cos(declination); in declination, 0.10"; and in magnitude, 0.06mag. The catalog contains 425 FK4 stars used for the adjustment to the FK4; 167 stars from the AGK3 zones +88deg. and +89deg.; 115 stars from the zone around the North Galactic Pole; stars from several PZT zones; some faint GC stars; reference stars for radio fields; and a few stars from earlier Brorfelde programs. The internal errors of a single observation are for right ascension, 0.0138 seconds/cos(delta), for declination, 0.216", and for the magnitude, 0.132 mag.
86. Bucharest KSZ Faint Stars, -11 to +11, 1950.0
ID:
ivo://CDS.VizieR/I/31
Title:
Bucharest KSZ Faint Stars, -11 to +11, 1950.0
Short Name:
I/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains the results of the differential observations of 3939 stars made with the Transit Circle of the Bucharest Observatory, from 1955 July 1 to 1962 June 16. The positions were observed simultaneously with the Catalog of the Southern Reference Star program. 105 stars were selected to be near extragalactic nebulae; the remaining 3852 stars were from the KSZ list. The positions are on the FK3R system for the equinox, 1950.0. Mean errors are 0.029s and 0.49" in right ascension and declination, respectively. The catalog contains for each star, in addition to the positions: the BD number, magnitude, spectral type, individual mean errors, epoch of the observations, number of observations in each coordinate, number of the star in the list of areas near extragalactic nebulae, and notes.
87. BVRI CCD photometry of NGC 1904
ID:
ivo://CDS.VizieR/J/AJ/107/230
Title:
BVRI CCD photometry of NGC 1904
Short Name:
J/AJ/107/230
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present BVRI photometry of three overlapping fields in the globular cluster NGC 1904 (M79), observed with a CCD camera and the 2.2m Max-Planck-Institute telescope at ESO/La Silla. We critically compare our photometry using the INVENTORY data reduction code with results derived by other investigators using different codes. These comparisons convince us that all modern codes give results reliable to at least +/-0.3mag at all levels, as long as the fields are not overly crowded. Specifically, our results for NGC 1904 (M79) are as follows: V(TO)=19.60+/-0.10 (estimated external error), with turnoff colors at B-V=0.40, V-R=0.27, V-I=0.57, and B-I=0.97, all with estimated external errors of +/-0.06. By fitting the four resulting ridge lines to the theoretical isochrones of VandenBerg & Bell [ApJS, 58, 561 (1985)] interpolated to [Fe/H]=-1.60, Y=0.20, and [O/Fe]=0.00, we derive an average value for the age of 16Gyr, where we have adopted E(B-V)=0.01.
88. BVRIK Photometry for the field of 4U 0142+61
ID:
ivo://CDS.VizieR/J/A+A/416/1037
Title:
BVRIK Photometry for the field of 4U 0142+61
Short Name:
J/A+A/416/1037
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new optical and infrared observations of the counterpart to the Anomalous X-ray Pulsar (AXP) 4U 0142+61 taken with the Keck I telescope. The counterpart is found to be variable in the infrared. This contrasts with our optical observations, which do not show any evidence for variability. Apart from the variability the AXP shows a remarkable spectral energy distribution. In particular, we find a sudden drop in flux going from V to B, presumably due to a spectral feature. We compare our results to those obtained for the two other securely identified AXP counterparts, to 1E 2259+586 and 1E 1048.1-5937. 4U 0142+61 is very similar to the former source in its X-ray timing and spectral properties, and we find that this similarity extends to the quiescent infrared to X-ray flux ratio. For 1E 1048.1-5937, which has different X-ray properties, the situation is less clear: in one observation, the infrared to X-ray flux ratio was much larger, but another observation gave an upper limit which is consistent with that observed for 4U 0142+61. Assuming the quiescent ratios are all similar, we estimate the optical and infrared brightnesses for the three AXPs that remain to be identified as well as for the four Soft Gamma-ray Repeaters. We also discuss briefly how the observed optical and infrared emission might arise, in particular in the context of the magnetar model.
89. BVR photometry of stars in NGC 2366
ID:
ivo://CDS.VizieR/J/AJ/110/212
Title:
BVR photometry of stars in NGC 2366
Short Name:
J/AJ/110/212
Date:
21 Oct 2021
Publisher:
CDS
Description:
The stellar content of the Im galaxy NGC 2366 is discussed on the basis of CCD BVR photometry. The three brightest blue and red stars have been used to estimate its distance, obtaining a value of 2.9pc. The spatial distribution of the young stellar population is discussed in the light of the integrated color indices and the color-magnitude diagrams of different zones of the galaxy. A generalized star formation burst seems to have taken place about 50Myr ago. The youngest stars are preferentially formed in the South-West part of the bar, where the giant H II complex NGC 2363 is located, being younger and bluer. The bar seems to play a role favoring star formation in one of its extremes. Self-propagation however, does not seem to be triggering star formation at large scale. A small region, populated by very young stars has also been found at the East of the galaxy.
90. Calern Observatory absolute declinations
ID:
ivo://CDS.VizieR/J/A+AS/137/269
Title:
Calern Observatory absolute declinations
Short Name:
J/A+AS/137/269
Date:
21 Oct 2021
Publisher:
CDS
Description:
A regular observational programme with a photoelectric astrolabe have been performed at ``Observatoire du Calern" (Observatoire de la Cote d'Azur, OCA, {phi}=+43{deg}44'55.011"; {lambda}=-0^h^27^m^42.44^s^, Calern, Caussols, France) for the last twenty years. It has been almost fully automatized between 1984 and 1987. Since 1988 the photoelectric astrolabe was used without any modification. In addition to determining the daily orientation of the local vertical, the yearly analysis of the residuals permits to derive corrections to the used star catalogue Vigouroux et al. (1992A&AS...96..477V). A global reduction method was applied for the ASPHO observations. The new form of the equations Martin & Leister (1997A&AS..126..169M) give us the possibility of using the entire set of the observing program using data taken at two zenith distances (30{deg} and 45{deg}). The program contains about 41648 stars' transits of 269 different stars taken at ``Observatoire du Calern" (OCA). The reduction was based on the HIPPARCOS system. We discuss the possibility of computing absolute declinations through stars belonging simultaneously to the 30{deg} and 45{deg} zenith distances programmes. The absolute declination corrections were determined for 185 stars with precision of 0.027" and the value of the determined equator correction is -0.018"+/-0.005". The instrumental effects were also determined. The mean epoch is 1995.29.

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