Heiles星光偏振源表的距离更正

星光偏振是研究星际介质磁场的有力工具之一.Heiles源表收集了9286颗恒星的偏振信息,是目前最大的光学波段星光偏振源表,被广泛使用.但该表中恒星的距离参数是以前的测光距离,很不确定.把Heiles源表和Gaia第2次数据释放(DR2)源表进行交叉证认,以位置和星等作为判据,匹配了7613颗恒星,并获得了这些恒星的三角视差距离和误差,超过90%的恒星距离相对误差小于20%.基于新的距离,展示了星光偏振在银河系内的分布并讨论了可能的应用.     

A Revisit to the Optical Starlight Polarization Catalogue by Heiles: Distance Update

Starlight polarization serves one of the powerful tools to study magnetic fields in the Galactic interstellar medium. Heiles catalogue contains polarization information for 9286 stars, and is by far the biggest. This catalogue has been extensively used to study the magnetic fields. However, the distance parameters of the stars in this catalogue are from photometric observations, and very uncertain. We cross match Heiles catalogue with Gaia Data Release 2 (DR2), and identify 7613 stars using both angular separation and magnitude as constraints. We then obtain precise distances from Gaia DR2 for these stars. For more than 90% of the stars, the relative errors of the new distances are within 20%. Based on the new catalogue, we demonstrate how starlight polarization can probe Galactic magnetic fields.     

A catalogue of stars suspected of bright active regions

We present a catalogue of field stars across the HR diagram suspected of bright active regions in their atmospheres.We aim at developing the first version of a database of active stars with bright regions (bright spots). Using a variety of databases and the internet we found and gathered all relevant archival data starting about 1973 and being important for developing such a catalogue. We found that the phenomenon starspot is now common to a variety of spectral type and luminosity classes. Our primary goal was to identify active solar and late type stars suspicious of bright active regions but the search offers expanded results including young T Tauri stars, eclipsing binaries with equal or mixed spectral types components (Algols,WUMa stars) and in some cases other types of objects. Moreover, the light curves analyses for eclipsing binaries offer reliable estimates for spot properties and it was found that 20% of binaries in the catalogue had a spot located near the L point (neck zone). At present, the catalogue consists of 134 stars and overall characteristics for them are organised in several files in ASCII format. The catalogue is electronically available (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The University of New South Wales Extrasolar Planet Search: a catalogue of variable stars from fields observed between 2004 and 2007

We present a new catalogue of variable stars compiled from the data taken for the University of New South Wales Extrasolar Planet Search. From 2004 October to 2007 May, 25 target fields were each observed for one to four months, resulting in ∼87 000 high-precision light curves with 1600–4400 data points. We have extracted a total of 850 variable light curves, 659 of which do not have a counterpart in the General Catalogue of Variable Stars, the New Suspected Variables catalogue or the All Sky Automated Survey southern variable star catalogue. The catalogue is detailed here, and includes 142 Algol-type eclipsing binaries, 23 β Lyrae-type eclipsing binaries, 218 contact eclipsing binaries, 53 RR Lyrae stars, 26 Cepheid stars, 13 rotationally variable active stars, 153 uncategorized pulsating stars with periods <10 d, including δ Scuti stars, and 222 long period variables with variability on time-scales of >10 d. As a general application of variable stars discovered by extrasolar planet transit search projects, we discuss several astrophysical problems which could benefit from carefully selected samples of bright variables. These include (i) the quest for contact binaries with the smallest mass ratio, which could be used to test theories of binary mergers; (ii) detached eclipsing binaries with pre-main-sequence components, which are important test objects for calibrating stellar evolutionary models and (iii) RR Lyrae-type pulsating stars exhibiting the Blazhko effect, which is one of the last great mysteries of pulsating star research.     

Catalogue of averaged stellar effective magnetic fields – II. Re-discussion of chemically peculiar A and B stars

This paper presents a catalogue and the method of determining averaged quadratic effective magnetic fields  〈 B _e〉  for 1212 main-sequence and giant stars, and 11 white dwarf stars. The catalogue includes stars that are members of several open clusters. We have compiled measurements of the longitudinal magnetic field for those stars, which were scattered in the existing literature. A new parameter, magnetization (MA), has been defined, and we present values of MA for stars of various spectral classes. Our sample includes a subset of 610 chemically peculiar early-type stars. We confirm the conclusion of our previous study that the number distribution of all chemically peculiar stars versus the averaged magnetic field strength is described by a decreasing exponential function. Relations of this type also hold for stars of all the analysed subclasses of chemical peculiarity. Magnetization tends to correlate with the effective temperature only at high MA, for He-weak and He-rich stars.     

Star catalogue in the fields of axial meridian circle of the Nikolaev observatory

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.     

Multiperiodicities from the Hipparcos epoch photometry and possible pulsation in early A-type stars

A selection criterion based on the relative strength of the largest peaks in the amplitude spectra, and an information criterion are used in combination to search for multiperiodicities in Hipparcos epoch photometry. The method is applied to all stars which have been classified as variable in the Hipparcos catalogue: periodic, unsolved and microvariables. Results are assessed critically: although there are many problems arising from aliasing, there are also a number of interesting frequency combinations which deserve further investigation. One such result is the possible occurrence of multiple periods of the order of a day in a few early A-type stars. The Hipparcos catalogue also contains a number of these stars with single periodicities: such stars with no obvious variability classifications are listed, and information about their properties (e.g., radial velocity variations) discussed. These stars may constitute a new class of pulsators.     

Photoelectric observations in a wide-field area around the Praesepe cluster

The PPM catalogue numbers, photoelectric magnitudes V, color-indexes U – B, B – V, V – R and rms errors of their determinations for 51 stars of the secondary wide-angle photoelectric standard are published. The catalogue accuracy of quantities mentioned above is 0.007, 0.015, 0.006, 0.006 mag, respectively. A list of ten stars which are probably variable is published.     

A new reduction of digitized photographic plates with selected asteroids obtained with the normal astrograph of the Pulkovo Observatory from 1948 to 1990

The results of a new reduction of 1545 photographic observations of 14 selected asteroids obtained with the Normal Astrograph of the Pulkovo Observatory from 1948 to 1990 are presented. Photographic plates stored in the archive of the observatory were digitized with a general purpose flatbed scanner using a specially developed technique. The accuracy of the reduction of photographic plates is measured. The UCAC3 catalogue has been used as a reference. Residual differences between coordinates of stars in the reference catalogue are used to analyze and tacking into account obtained instrumental systematic errors. Equatorial coordinates of 1378 individual observations of target asteroids are obtained. They are compared with the results of the reduction of the material made earlier. Among the objects of the background, positions of 1475 stars with large proper motions from the LSPM catalogue are measured.     

Reduction of micrometer cometary observations to the PPM star catalogue

An adaptation of Bielicki's method of reduction of old cometary micrometer observations of the comet-minus-star type to the PPM star catalogue is presented. A fully automatic utility is described which reduces old positions of stars to the coordinates in the PPM star catalogue for comet-minus-star astrometric observations. The reduction clears observations from systematic errors in old catalogues and decreases the mean error of observations. That may have implications for orbit improvement. The utility predicts new positions of stars in the PPM catalogue as needed and can also restore observations which have been previously rejected due to a selection criterion. It helps to get all data in one, coherent reference frame with maximum possible precision when there are lots of old and new observations of the same object. As an illustration, results of application of the utility to observations of comets 122P/de Vico and 109P/Swift-Tuttle are presented.     

Candidate red clump giants in the PPMX catalogue

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.     

The MOA catalogue of eclipsing binary stars in the Small Magellanic Cloud

We present a catalogue of 167 eclipsing binary stars in the Small Magellanic Cloud (SMC) derived from the data base of time-series photometry for 400 000 SMC stars acquired by the Microlensing Observations in Astrophysics (MOA) project during 1997. We print coordinates, ephemerides, magnitudes and light curves for the 35 new detections; similar data and finding charts are available electronically for the whole catalogue. The majority of periods lie within the range 0.4 to 20 d; six systems are possibly eccentric while 14 are probably or certainly so. The majority of the newly identified systems lie in the outer regions of the SMC.     

A compiled catalogue of reference stars around 227 ICRF extragalactic radio sources

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.     

Computations of radial velocities for O-type stars

From the study of the spectra of eighteen O-type stars can be argued that a large Compton redshift is present, that could be due to the scattering of the light of these stars in the surrounding envelopes of interstellar matter. The new values of radial velocities, obtained for the above-quoted stars by means of a formula which takes into account the generalized Compton effect, are inconsistent with the values given in the stellar catalogue.     

A catalogue of potential adaptive optics survey fields from the UKIRT archive

We present a multicolour catalogue of faint galaxies situated close to bright stars,   V ≲ 15  , with the aim of identifying high-redshift galaxies suitable for study with adaptive optics-equipped near-infrared imagers and spectrographs. The catalogue is constructed from archival calibration observations of the United Kingdom Infrared Telescope (UKIRT) Faint Standard stars with the UKIRT Fast Track Imager (UFTI) camera on UKIRT. We have analysed the deepest 16 fields from the archive to provide a catalogue of galaxies brighter than   K ∼ 20.3  lying between 3 and 25 arcsec of the guide stars. We identify 111 objects in a total survey area of  8.7 arcmin²  . Of these, 87 are classified as galaxies based on their light profiles in our ∼0.5 arcsec median seeing K -band images. 12 of the galaxies have  ( J − K ) ≥ 2.0  consistent with them lying at high redshifts,   z ≳ 2  . These 12 very red galaxies have K -band magnitudes of   K = 18.1–20.1  and separations from the guide stars of 4–20 arcsec and hence are very well suited to adaptive optics studies to investigate their morphologies and spectral properties on sub-kpc scales. We provide coordinates and JHK photometry for all catalogued objects.     

Frequency of Be and Ae stars in spectroscopic binaries

The frequency of Be and Ae stars in spectroscopic binaries and Algol binaries is examined based on the available catalogue data, and compared with that of stars in theBright Star Catalogue. It is shown that in binary systems Be and Ae stars reveal different statistical behaviours. The frequency of Be stars in spectroscopic binaries shows a notable peak in its orbital-period distribution in the range of 100–300 days, suggesting a statistical group separated from Algol systems. In contrast, most of Ae stars in spectroscopic binaries belong to the Algol systems.     

Occultations by possible material in Saturn’s outer magnetosphere

Results of a search for occultations of stars in the SAO catalogue by Saturn’s outer magnetosphere during 1988 are presented.     

Separation between Gould Belt and Disk Stars in the Solar Neighbourhood

The adoption of a parametric model for the spatial distribution of Gould Belt and Galactic Disk stars allows the classification by their membership probabilities of stars from the Hipparcos catalogue in the Solar vicinity and the estimation of structural parameters for both stellar systems for several age groups. The observed kinematics of Gould Belt and Disk stars are shown to be different. This revised version was published online in July 2006 with corrections to the Cover Date.     

Stars with solar-type activity: GTSh10 catalogue

A catalogue of dwarf stars with different manifestations of Solar-type activity is compiled based on publications of the last 10–15 years. The catalogue includes objects with dark spots, hydrogen and calcium chromospheric emission, short-lived flares in different wavelength ranges, and radio and X-ray emission of stellar corona. The resulting compiled list includes 5535 objects.     

A photometric catalogue of visual and multiple stellar systems

Summary The catalogue gives the parameters of theUBV, uvby, and Geneva photometries for more than 200 stars. It gives also the first statistics with respect to the different caracteristics of visual systems: separation, difference of the magnitude of components,... etc. For 11713 components of stellar systems the catalogue, in its actual form, gives the parameters of theUBV, uvbyβ and Geneva photometric systems. A concise statistics presents the distribution of the stars in the different photometric systems and the relations between the difference in the magnitudes and separation of the components. CNRS UA 040389.