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1.
N. V. Maigurova M. V. Martynov G. I. Pinigin 《Kinematics and Physics of Celestial Bodies》2013,29(1):44-51
On the base of CCD-observations made with the axial meridian circle of the Nikolaev Observatory from 2008 to 2009, we compiled a catalogue for astrometric positions and proper motions for 140321 stars located in an ecliptic zone and around high proper motion stars. The root-meansquare error for a star position is 20–65 mas in right ascension and 30–70 mas in declination. The UCAC2 catalogue is used as a reference for astrometric reductions. To derive stars’ proper motion and to estimate systematic errors of the compiled catalogue, cross-identification of the obtained data with modern astronomic catalogues Tycho2, 2MASS, CMC14, LSPM, PPMX, USNO-A2, and XPM-1.0 is performed. In addition to star position and proper motion, our catalogue contains photometric values B, V, r’, J, H, and K taken from other catalogues. 相似文献
2.
The absolute proper motions of about 275 million stars from the Kharkov XPM catalog have been obtained by comparing their
positions in the 2MASS and USNO-A2.0 catalogs with an epoch difference of about 45 yr for northern-hemisphere stars and about
17 yr for southern-hemisphere stars. The zero point of the system of absolute proper motions has been determined using 1.45
million galaxies. The equatorial components of the residual rotation vector of the ICRS/UCAC2 coordinate system relative to
the system of extragalactic sources have been determined by comparing the XPM and UCAC2 stellar proper motions: ω
x,y,z = (−0.06, 0.17, −0.84) ± (0.15, 0.14, 0.14) mas yr−1. These parameters have been calculated using about 1 million faintest UCAC2 stars with magnitudes R
UCAC2 > 16
m
and J > 14
m
. 7, for which the color and magnitude equation effects are negligible. 相似文献
3.
The results of a comprehensive study of the Galactic open cluster NGC 2323 (M50) are presented. The positions of stars to
a limiting magnitude {ie74-1} in a {ie74-2} area centered on the cluster were measured on six plates from the Pulkovo normal
astrograph with a maximum epoch difference of 60 yr. The measurements were performed with the Pulkovo “Fantasy” automated
measuring system upgraded in 2010. The corresponding areas from the USNO-A2.0, USNO-B1, and 2MASS catalogues were used as
additional plates. As a result, the relative proper motions of stars were obtained with a root-mean-square error of 5.85 mas
yr−1. A catalogue of UBV and JHK magnitudes for objects in the investigated area was compiled from available published resources. The astrometric selection
of cluster members was made by the maximum likelihood method. A high individual cluster membership probability of a star (P ≥ 80%) served as the first selection criterion. The position of a star on the photometric color-magnitude (V ∝ (B-V), J ∝ (J-K)) diagrams of the cluster was considered as the second criterion. The position of an object on the color-color ((U-B)-(B-V), (J-H)-(J-K)) diagrams served as the third criterion. On the basis of these criteria, it was established that 508 stars are members of
NGC 2323. These data were used to refine the physical parameters of the cluster: the mean reddening {ie74-3}, the true distance
modulus {ie74-4}, and the cluster age of about 140 Myr from the grid of isochrones computed by the Padova group for solar
chemical composition. Two tables contain the catalogues of proper motions and photometry for stars in the area. The luminosity
and mass functions were constructed. The cluster membership of red and blue giants, variable, double, and multiple stars was
considered. The position of the cluster center was improved: {ie74-5}, δ = −08°20′16″(2000.0). 相似文献
4.
After publication of the Hipparcos catalogue (in 1997), a few new astrometric catalogues have appeared (TYCHO‐2, ARIHIP, etc.), as a good combination of the Hipparcos satellite and ground‐based data, to get more accurate coordinates and proper motions of stars than the Hipparcos catalogue ones. There are also investigations on improving the Hipparcos coordinates and proper motions by using the astrometric observations of latitude and universal time variations (via observed stars referred to Hipparcos catalogue), together with Hipparcos data, carried out during the last few years. These kind of ground‐based data were collected at the end of the last century by J. Vondrák. There are about 4.4 million optical observations made worldwide at 33 observatories and with 47 instruments during 1899.7–1992.0; our Belgrade visual zenith telescope data (for the period 1949.0‐1986.0) were included. First of all, these data were used to determine the Earth Orientation Parameters – EOP, but they are also useful for the opposite task – to check the accuracy of coordinates and proper motions of Hipparcos stars which were observed from the ground over many decades. Here, we use the latitude part of ten Photographic Zenith Tubes – PZT data (more than 0.9 million observations made at 6 observatories during the time interval 1915.8–1992.0), and combine them with the Hipparcos catalogue ones, with suitable weights, in order to check the proper motions in declination for 807 common PZT/Hipparcos stars (and to construct the PZT catalogue of μδ for 807 stars). Our standard errors in proper motions in declination of these stars are less than or equal to the Hipparcos ones for 423 stars. The mean value of standard errors of 313 stars observed over more than 20 years by PZT is 0.40 mas/yr. This is 53% of 0.75 mas/yr (the suitable value from the Hipparcos catalogue). We used the Least Squares Method – LSM with the linear model. Our results are in good agreement with the Earth Orientation Catalogue – EOC‐2 and the new Hipparcos ones. The main steps of the method and the investigations of systematic errors in determined proper motions (the proper motion differences with respect to the Hipparcos values, the EOC‐2 ones and the new Hipparcos ones, as a function of α, δ, and magnitude) are presented here. A comparison of the four catalogues by pairs shows that there is no significant relationship between the differences of their μδ values and magnitudes and color indices of the common 807 stars. All catalogues have relatively small random and systematic errors which are close to each other. However, the comparison shows that our formal errors are too small. They are underestimated by a factor of nearly 1.7 (for EOC‐2, it is 2.0) if we take the new Hipparcos (or Hipparcos) data as reference (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
5.
I. N. Kharchenko L. Pakulyak O. Molotaj V. Tel'nyuk-Adamchuk 《Astronomische Nachrichten》1995,316(6):401-410
The PPM catalogue contains the most complete and accurate information concerning positions, proper motions and some astrophysical data for practically all stars (about 379000) down to 10m-11m over the whole sky. The systems and rms errors of the PPm positions, proper motions, stellar magnitudes and spectral classification are studied by comparison with catalogues of stellar characteristics and on the basis of the PPM data itself. The residual errors of stellar data in the PPM catalogue are small and/or they can be determined and eliminated. 相似文献
6.
V. P. Ryl’kov N. V. Narizhnaya A. A. Dement’eva G. I. Pinigin N. V. Maigurova M. V. Martynov 《Kinematics and Physics of Celestial Bodies》2011,27(6):299-303
A compiled catalogue of 21 440 stars with magnitudes between 10 and 17 is prepared from original observations made at the end of the 20th century to the beginning of the 21st century. The catalogue contains 227 fields of the celestial sphere centered at ICRF extragalactic radio sources with declinations of ?17 to +89°. The field size is 40′ for both right ascension and declination. The internal accuracy of positions for both coordinates is no worse than 0.1″. A comparison of the stellar positions with the UCAC2 and CMC13 catalogues shows that the average external accuracy is approximately 0.05–0.15″. The positions of 10 795 stars with declinations to +50° are given for the epoch and equinox of J2000.0, whereas the positions of other stars are given for the epoch of observation. 相似文献
7.
A. A. Chemel E. V. Glushkova A. K. Dambis A. S. Rastorguev L. N. Yalyalieva A. D. Klinichev 《Astrophysical Bulletin》2018,73(2):162-177
We cross-match objects from several different astronomical catalogs to determine the absolute proper motions of stars within the 30-arcmin radius fields of 115 Milky-Way globular clusters with the accuracy of 1–2 mas yr?1. The proper motions are based on positional data recovered from the USNO-B1, 2MASS, URAT1, ALLWISE, UCAC5, and Gaia DR1 surveys with up to ten positions spanning an epoch difference of up to about 65 years, and reduced to Gaia DR1 TGAS frame using UCAC5 as the reference catalog. Cluster members are photometrically identified by selecting horizontal- and red-giant branch stars on color–magnitude diagrams, and the mean absolute proper motions of the clusters with a typical formal error of about 0.4 mas yr?1 are computed by averaging the proper motions of selected members. The inferred absolute proper motions of clusters are combined with available radial-velocity data and heliocentric distance estimates to compute the cluster orbits in terms of the Galactic potential models based on Miyamoto and Nagai disk, Hernquist spheroid, and modified isothermal dark-matter halo (axisymmetric model without a bar) and the same model + rotating Ferre’s bar (non-axisymmetric). Five distant clusters have higher-than-escape velocities, most likely due to large errors of computed transversal velocities, whereas the computed orbits of all other clusters remain bound to the Galaxy. Unlike previously published results, we find the bar to affect substantially the orbits of most of the clusters, even those at large Galactocentric distances, bringing appreciable chaotization, especially in the portions of the orbits close to the Galactic center, and stretching out the orbits of some of the thick-disk clusters. 相似文献
8.
9.
10.
Using modern astronomical databases, particularly 2MASS All - Sky Data Release Point Source Catalog and USNO-B1.0 catalog, we investigate the properties of about 840 FBS red stars in order to clarifiy their nature. We use and analyse their JHK 2MASS photometry, together with the R-band magnitudes and the proper motions provided by USNO - B1.0. Approximately 70% of all objects appear to be Asymptotic Giant Branch stars, 18% are giants, and close to 12% are objects with detectable proper motions, allowing to consider them as dwarf M-type stars. When plotted in a J - K versus R - K colour-colour diagram, one finds that objects with proper motions are well separated into a narrow belt.__________Published in Astrofizika, Vol. 48, No. 3, pp. 383–392 (August 2005). 相似文献
11.
Astrometric CCD observations of 1123 stars with large proper motions (μ > 300 mas yr−1) from the LSPM (I/298) catalog in the declination zone +30°–+70° have been carried out with the Pulkovo normal astrograph
since 2006. The observational program includes mostly stars that previously have not entered into high-accuracy projects to
determine the proper motions. Our studies are aimed at determining new proper motions of fast stars in the HCRF/UCAC3 system
and searching for stars with invisible companions in the immediate Galactic neighborhoods of the Sun. Having analyzed about
10 000 CCD frames, we have obtained the equatorial coordinates of 414 program stars in the HCRF/UCAC3 system at an accuracy
level of 10–50 mas and determined their new proper motions. To derive the proper motions, we have used the data from several
star catalogs and surveys (M2000, CMC14, 2MASS, SDSS) as early epochs. The epoch differences range from 5 to 13 years (on
average, about 10 years); the mean accuracy of the derived proper motions is 4–5 mas yr−1. For 70 stars, we have revealed significant differences between the derived proper motions and those from the LSPM and I/306A
catalogs (these proper motions characterize the mean motion of the photocenter in 50 years or more). Apart from systematic
errors, these differences can result from the existence of invisible components of the program stars. 相似文献
12.
We present comparison results of our Independent Latitude (IL) catalogue of μδ determinations for 1120 bright stars with the Hipparcos, new Hipparcos and Earth Orientation Catalogue (EOC‐2) values. Also, we took into consideration the EOC3 and EOC4 (recent versions of EOC catalogues). Our μδ values are based on zenith telescope observations from seven Independent Latitude (IL) observatories. The IL measures are spanning a time baseline of up to 90 years which is the key advantage to the accurate determination of μδ. The short interval of the Hipparcos satellite observations is a disadvantage for a good accuracy of stellar proper motion, especially in the case of double and multiple stars. For this reason many astrometric catalogues have appeared after the publication of the Hipparcos including our IL catalogue. These catalogues are an appropriate combination of the Hipparcos satellite and ground‐based data which yields more accurate stellar coordinates and/or their proper motions. Among various types of ground‐based observations the latitude and universal time variations obtained from several million observations of stars reduced to the Hipparcos reference system were used for this purpose. These observations were obtained during almost the entire last century and were originally used to determine the Earth Orientation Parameters. It is also possible to use these data in the inverse task of checking the accuracy of stellar coordinates and/or their proper motions listed in the Hipparcos Catalogue. Such latitude and universal time variations data are the basis of the EOC and IL catalogues. In this paper, we computed the differences in μδ values between pairs of catalogues and analyzed the results to characterize the μδ errors for the four catalogues with a special focus on our IL catalogue. The standard errors of μδ for IL stars observed over more than 20 years are mostly smaller than or equal to the Hipparcos errors, and close to the accuracy level of the EOC‐2 (EOC‐3, EOC‐4) and the new Hipparcos. The resulting investigations of errors of differences of μδ, show that all four catalogues have relatively small random and systematic errors which are close to each other meaning that the corresponding μδ values have a high accuracy. Our sample also contains detected double and multiple stars for which the effects of the orbital and proper motions are difficult to separate. The differences of μδ values for these stars generally exceed those obtained for single stars. Also, these discrepancies could be attributed to effect of possible, still unrecognized, astrometric binaries. These investigations about the proper motions and double stars are in line with the activity of the IAU Working Group on Astrometry by Small Ground‐Based Telescopes. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
13.
N. V. Kharchenko V. S. Kislyuk S. F. Rybka A. I. Yatsenko 《Astrophysics and Space Science》1991,177(1-2):65-71
The works of the Goloseevo Observatory (Kiev, U.S.S.R.) on the compilation of catalogues of absolute proper motions measured with respect to faint galaxies are discussed. Using these catalogues, some astrometric and stellar characteristics have been obtained. Particular attention is paid to the problem of improving the accuracy of stellar position and proper motion determinations. The optimum procedure for compiling the consolidated catalogue intended for the improvement of fundamental reference frame, kinematic characteristics of stars as well as for the solution of applied problems is developed. 相似文献
14.
E. Høg G. Bässgen U. Bastian D. Egret J. L. Halbwachs 《Astrophysics and Space Science》1991,177(1-2):109-114
The TICR catalogue is arevision of TIC, theTYCHO Input Catalogue, and will contain positions derived from the first 12 months of TYCHO observations. Its properties, its role in TYCHO data analysis, and other possible uses are discussed. Since TICR will list about 500 000 stars with a positional precision of 0."15 (rms) and since it should become available early, it could be published two years after launch, during the mission. Preferably, proper motions should be included based on TICR and older ground-based first epoch positions, thus obtaining a precision about 0.003 /year for the stars in the northern sky, but decreasing to 0.010 "/year in some parts of the southern celestial hemisphere. 相似文献
15.
This paper presents the RCGP catalogue of more than 0.5 million candidate red clump stars with the limiting magnitude K
s
= 9.5
m
. These stars are selected from the PPMX catalogue as the most probable red clump members by analyzing the color-reduced proper
motion diagrams built from the proper motions given in PPMX and J, K
s
-photometry given in the 2MASS catalogue. Reddening of the selected stars is used to find extinction in the K
s
-band and to consider it in the further analysis. The two-dimensional galactic rotation model generalized by Ogorodnikov is
used to investigate the tangential velocity field of the selected red clump members, most of which are thin disk stars located
within 1.5 kpc from the sun. The values of kinematic parameters and solar components are determined as a function of stellar
heights above the galactic equatorial plane and their heliocentric distances. 相似文献
16.
S. Bilir S. Karaali S. Ak K. B. Co&#;kuno&#;lu E. Yaz A. Cabrera-Lavers 《Monthly notices of the Royal Astronomical Society》2009,396(3):1589-1595
We present a new luminosity–colour relation based on trigonometric parallaxes for thin-disc main-sequence stars in Sloan Digital Sky Survey (SDSS) photometry. We matched stars from the newly reduced Hipparcos catalogue with the ones taken from Two-Micron All-Sky Survey (2MASS) All-Sky Catalogue of Point Sources, and applied a series of constraints, i.e. relative parallax errors (σπ /π≤ 0.05) , metallicity (−0.30 ≤[M/H]≤ 0.20 dex) , age (0 ≤ t ≤ 10 Gyr) and surface gravity (log g > 4) , and obtained a sample of thin-disc main-sequence stars. Then, we used our previous transformation equations ( Bilir et al. 2008a ) between SDSS and 2MASS photometries and calibrated the Mg absolute magnitudes to the ( g − r )0 and ( r − i )0 colours. The transformation formulae between 2MASS and SDSS photometries along with the absolute magnitude calibration provide space densities for bright stars which saturate the SDSS magnitudes. 相似文献
17.
A new method for selecting stars in the Galactic bar based on 2MASS infrared photometry in combination with stellar proper motions from the Kharkiv XPM catalogue has been implemented. In accordance with this method, red clump and red giant branch stars are preselected on the color-magnitude diagram and their photometric distances are calculated. Since the stellar proper motions are indicators of a larger velocity dispersion toward the bar and the spiral arms compared to the stars with circular orbits, applying the constraints on the proper motions of the preselected stars that take into account the Galactic rotation has allowed the background stars to be eliminated. Based on a joint analysis of the velocities of the selected stars and their distribution on the Galactic plane, we have confidently identified the segment of the Galactic bar nearest to the Sun with an orientation of 20°–25° with respect to the Galactic center-Sun direction and a semimajor axis of no more than 3 kpc. 相似文献
18.
N. R. Deacon N. C. Hambly R. R. King M. J. McCaughrean 《Monthly notices of the Royal Astronomical Society》2009,394(2):857-871
The UK Infrared Telescope Infrared Deep Sky Survey (UKIDSS) is the first of a new generation of infrared surveys. Here, we combine the data from two UKIDSS components, the Large Area Survey (LAS) and the Galactic Cluster Survey (GCS), with Two-Micron All-Sky Survey (2MASS) data to produce an infrared proper motion survey for low-mass stars and brown dwarfs. In total, we detect 267 low-mass stars and brown dwarfs with significant proper motions. We recover all 10 known single L dwarfs and the one known T dwarf above the 2MASS detection limit in our LAS survey area and identify eight additional new candidate L dwarfs. We also find one new candidate L dwarf in our GCS sample. Our sample also contains objects from 11 potential common proper motion binaries. Finally, we test our proper motions and find that while the LAS objects have proper motions consistent with absolute proper motions, the GCS stars may have proper motions which are significantly underestimated. This is possibly due to the bulk motion of some of the local astrometric reference stars used in the proper motion determination. 相似文献
19.
A. A. Volchkov A. V. Kuzmin V. V. Nesterov U. Bastian S. Rser 《Astronomische Nachrichten》1993,314(1):43-46
Proper motions of the stars of the Astrographic Catalogue are being derived, using the Hubble Space Telecope Guide Star Catalogue as second epoch. Results on the San Fernando and Cordoba AC zones are presented. Identification with GSC stars (i.e. determination of proper motion) was successful for 97 percent of all AC stars. Comparison of the proper motions thus derived with those of Preliminary PPM South shows that the accuracy is about 0.8 to 0.9 arcsec per century. Thus we can derive proper motions for about 4 million stars, with an accuracy higher than that of the SAO Catalogue. 相似文献
20.
利用上海天文台佘山４０ 厘米折射望远镜拍摄的２ 个底片天区１５ 张照相底片上的３１ 次观测,以ＡＣＴ 星表作为初始参考星表,按中心重叠法进行归算处理,得到了１６ 颗依巴谷星和３８ 颗场星的高精度位置和自行结果,其中依巴谷星的赤经和赤纬标准误差的平均值分别为１０ ．５ ｍａｓ 和７ ．５ ｍａｓ,赤经自行和赤纬自行标准误差的平均值分别为０ ．７０ ｍａｓ／ｙｒ 和０ ．５９ ｍａｓ／ｙｒ 相似文献