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I/237   The Washington Visual Double Star Catalog, 1996.0    (Worley+, 1996)

The Washington Visual Double Star Catalog, 1996.0 Worley C.E., Douglass G.G. <US Naval Observatory (1996); Astron. Astrophys. Suppl. Ser. 125, 523 (1997)> =1997A&AS..125..523W
ADC_Keywords: Stars, double and multiple ; Positional data Description: The Washington Visual Double Star Catalog, 1996.0 (WDS) is the successor to the catalog of the same name dated 1984 I/107. The WDS is intended to contain all known visual double stars for which at least one differential measure has been published through the end of 1995. It includes a discoverer code, the date of the first and last observations, the number of observations, the position angle and separation for the first and last observation, the magnitudes and spectral types of the components (when available) the proper motion of the system, Durchmusterung numbers of the components and notes for further information. Introduction: The reader is reminded that the WDS is not inclusive of all pairs which have been more casually noted, although it does, in fact, include some of them. The data base upon which the present WDS rests consists of the approximately 180000 measures transferred from the Lick Observatory in 1965, which, with few exceptions, covered the interval 1927-1963, augmented by all subsequent measures (about 118000), and some 154000 pre-1927 means. These latter are the result of a continuing project to build a truly comprehensive and complete data base. Thus, approximately 452000 individual means, representing over a million individual observations, form the basic material from which the WDS is constructed. We have not included a small amount of data because of unresolved questions concerning it. The WDS contains 78100 double stars, counting, as did the IDS, multiple components in the same system as separate pairs. Comparison of the present catalog with its IDS predecessor will reveal that a considerable number (about 1000) of previously catalogued objects have been removed from the WDS in the process of editing the data. The most common reason for removal is that the object is not certainly double. We wish to emphasize that the WDS is not intended to be an "astrometric" catalog in the sense usually employed, but rather is to be considered a finding list for observers, as well as serving as a notification of which objects are known doubles or multiples, along with some basic astrometric and astrophysical parameters. In addition, the WDS offers information on the amount of motion and frequency with which a given object has been observed, which is sufficient, in fact, to provide a basis for the construction of observational programs. Finally, the data can be used (with proper precautions) to analyze certain statistical properties of visual double stars. Of course, as has been true for many years, the individual measures of specific objects are available and will be supplied to requesters provided that the amount of data desired is reasonable. Request for Acknowledgment: If the WDS and associated databases were helpful for your research work, the following acknowledgement would be appreciated: ``This research has made use of the Washington Double Star Catalog maintained at the U.S. Naval Observatory.'' File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file wds.doc 80 285 WDS Catalog Documentation catalog.dat 84 78100 WDS Catalog notes.dat 80 8396 Notes to the WDS notesyns.dat 80 721 Notes (synonyms) to the WDS refs.dat 80 2181 Discoverer References disc.dat 80 65 Discoverer Codes (Additional)
See also: I/211 : CCDM (Components of Double and Multiple stars) (Dommanget+ 1994) Byte-by-byte Description of file: catalog.dat
Bytes Format Units Label Explanations
1- 2 I2 h RAh *Right Ascension J2000 (hours) 3- 5 I3 0.1min RAdm *Right Ascension J2000 (minutes) 6 A1 --- DE- *Declination J2000 (sign) 7- 8 I2 deg DEd *Declination J2000 (degrees) 9- 10 I2 arcmin DEm *Declination J2000 (minutes) 11- 17 A7 --- DiscName *Discoverer Code & Number 18- 22 A5 --- Comp *Component Identification 24- 26 I3 a Date1 ?Date of first satisfactory observation (+1000) 27- 29 I3 a Date2 ?Date of last satisfactory observation (+1000) 30- 31 I2 --- NumObs *?Number of measures of the object 32- 34 A3 deg pa1 *Position Angle for Date1 35- 37 A3 deg pa2 *Position Angle for Date2 38- 42 F5.1 arcsec Sep1 *?Angular Separation for Date1 43- 47 F5.1 arcsec Sep2 *?Angular Separation for Date2 48- 52 F5.2 mag MagA ?Magnitude of component 1 53- 57 F5.2 mag MagB ?Magnitude of component 2 58- 66 A9 --- Sp *Spectral Types of Primary/Secondary 67- 70 I4 mas/a pmRA *?Proper Motion in Right Ascension 71- 74 I4 mas/a pmDE *?Proper Motion in Declination 75- 82 A8 --- DM *Durchmusterung Zone & Number 83- 84 A2 --- note *Notes
Note on RAh, RAdm, DE-, DEd, DEm: The positions given represent our best estimates of these values. Where possible, these are based on the ACRS and PPM data, with proper motion incorporated. (Code "p" in cols. 79-80). Note on DiscName: The discoverer, identified by a one-to-three letter code, and the discoverer's number, if assigned. The reference list ("wdsref.dat") should be consulted first to identify individuals. However, some discoverer designations do not appear in this list, for various reasons, and a supplementary list is provided (wdsrefa.dat"). Note on Comp: Components, when the object has more than two. The Lick IDS scheme has been discontinued, and components are now referred to by the traditionally employed lower-case letters. The rather awkward upper-case designations, e.g. ABXC, have been changed to the form AB-C, etc. We have noted some confusion on the part of observers and students alike, as to how to designate components in multiple systems. Traditionally, these have been designated in order of separation, thus AB, AC,...., or in the cases where close pairs are observed blended, AB-C, AB-D,.... In some instances, differing resolution limits produce situations where observations are intermixed, thus AC, AB-C, and so forth. (In all too many cases, carelessness on the part of the observer does not permit us to determine with certainty how the observation is to be interpreted). There are also many instances where later observations have revealed a closer companion; these are designated Aa, Bb, etc. In a few cases wider, later discoveries have also been so denoted. Note on NumObs: The number of measures of the object. When there are more than 99, the number 99 is used. For smaller numbers of observations, the value in these columns is intended to accurately reflect the actual number. Note on pa1 and pa2: Position angles in degrees for the dates listed in columns 24-29. For some pairs, the discoverers have given only crude estimates, such as NF or SP; in such cases these are listed. Position angles are unprecessed in this catalog (i.e. they are for the mean date of observation). Note on Sep1 and Sep2: The distances in seconds of arc, and tenths, for the dates listed in columns 24-29. Some separations are treated by the codes found in columns 79-80, or in the Notes. In cases where there has been no appreciable motion observed over the duration of observation, only one position angle and separation is listed. Note on Sp: Spectral type of A, or of two components, if space permits. (See "wdscat.doc" for discussion). Note on pmRA and pmDE: The components of the proper motion in seconds of arc per 1000 years, in right ascension reduced to great circle, and in declination. Specifically, this catalog lists 15mu(alpha)*cos(delta), where mu(alpha) is in seconds of time, and mu(delta) is in seconds of arc. Both quantities are reduced to a time unit of 1000 years. The exceptions are those objects coded P, Q, and R, for which an explanation is given under the description for Columns 79 and 80. + and - indicate eastward and westward motions in Right Ascension, and + and - those north and south in Declination. Note on DM: Durchmusterung number of the object in the system used by the Henry Draper Catalogue: Bonn from +89 degrees to -22 degrees inclusive, Cordoba from -23 degrees to -51 degrees inclusive, Cape Photographic from -52 degrees to -89 degrees inclusive. When a star is not contained in the Durchmusterung proper to its declination zone, but is contained in another Durchmusterung, this is so indicated in the Notes. Other components having different Durchmusterung numbers are also indicated in the Notes ("notesmn.dat"). Note on note: The following codes are contained in these columns: N: Notes found in the Notes table. O: Orbit. Where motion has exceeded 360 degrees, no values are listed in the position angle and separation columns. Orbits may be found in the "Fourth Catalog of Orbits of Visual Binary Stars" (Worley and Heintz, 1983), and in the Information Circulars published by Commission 26 of the IAU, as well as in the literature. P: 100 year proper motion in right ascension. Q: 100 year proper motion in declination. R: 100 year proper motion in right ascension and declination. a: Pair appears in an appendix list, not part of the discoverer's regular numbering system. r: Pair was listed, but in a "rejected" list, not part of the discoverer's regular numbering sequence. s: Pair has other discoverer's designations and numbers in the literature due to duplicate discovery. We have given credit to the earliest discovery observation (and correct identification) reported in the literature. The List of Synonyms follows the List of Additional Discoverers. p: Coordinates and proper motions from the ACRS, PPM, IRS, and FK5 catalogs. 6: Separation given in minutes of arc rather than se- conds.
Byte-by-byte Description of file: notes*.dat
Bytes Format Units Label Explanations
1- 2 I2 h RAh *Right Ascension J2000 (hours) 4- 7 F4.1 min RAm *Right Ascension J2000 (minutes) 9 A1 --- DE- *Declination J2000 (sign) 10- 11 I2 deg DEd *Declination J2000 (degrees) 13- 14 I2 arcmin DEm *Declination J2000 (minutes) 16- 23 A8 --- DiscName *Discoverer Code & Number 24 A1 --- Cont *[+] Continuation flag 25- 80 A56 --- Text *Text of Note
Note on RAh, RAm, DE-, DEd, DEm: The positions given represent our best estimates of these values. Where possible, these are based on the ACRS and PPM data, with proper motion incorporated. There may be several lines per system, see Cont Note on DiscName: The discoverer, identified by a one-to-three letter code (see wdsref.dat and wdsrefa.dat for the meaning), and the discoverer's number, if assigned. The reference list ("wdsref.dat") should be consulted first to identify individuals. However, some discoverer designations do not appear in this list, for various reasons, and a supplementary list is provided ("wdsrefa.dat"). Note on Cont: The + indicates that a continuation exists on the next line: only the last line of the comment has this flag set to blank. Note on Text: We have extensively revised the Notes to include much more information on orbital motion and multiplicity (including astrometric, photometric, and spectroscopic), variability, composite spectra, etc. In the case where an orbit exists for a pair, we give the period (P) and the semi-major axis (a) in seconds of arc, plus an indication of the direction of motion.
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 3 A3 --- Disc Discoverer Code 4- 5 I2 --- RefNo Reference number of publication 7- 24 A18 --- Obs Observer(s) 25- 80 A56 --- Publ Publication reference for measures
Byte-by-byte Description of file: disc.dat
Bytes Format Units Label Explanations
1- 3 A3 --- Disc Discoverer Code 4- 80 A77 --- Obs Observer
History: * 02-Oct-1996: Catalogue prepared by G.G. Douglass [U.S. Naval Observatory] * 26-Sep-1997: For 5 stars, the erroneous magnitudes were corrected (concerns WDS J04497+1554, J06283+0155, J12500+4708, J19344+0824 and J23126+0241) Acknowledgement: The ADC thanks Dr. Douglass for not only forwarding the Washington Double Star Catalog and the accompanying documentation in good shape but also for forwarding a revised version correcting the few mistakes discovered in the first version.
(End) G. G. Douglass [U.S. Naval Observatory] 02-Oct-1996
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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