Fourth Catalog of Interferometric Measurements of Binary Stars
William I. Hartkopf, Brian D. Mason, & Gary L. Wycoff
U.S. Naval Observatory, Washington, DC
Harold A. McAlister
Center for High Angular Resolution Astronomy
Georgia State University, Atlanta, GA 30303
Note: As of January 2018, the Fourth Interferometric Catalog will no longer be
maintained. This change, after 35+ years, is due to staffing limitations at USNO
(primarily the retirement of WIH). Over the coming months, the observations of
single stars / never-resolved pairs will be copied to a new WDS "single-star
supplement", whose format will be similar to that of the WDSS. All measures of
resolved pairs will be copied to the main WDS catalog as needed. Preliminary
versions of the WDSSSS will be posted; your comments and suggestions regarding
content, format, etc. will be welcome, as always.
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The following description is adapted from a paper by Hartkopf et al. (2001, AJ,
122, 3480.)
The "Fourth Catalog of Interferometric Measurements of Binary Stars" includes
all published measures of binary and multiple star systems obtained by high-
resolution techniques (speckle interferometry, photoelectric occultation
timings, etc.), as well as negative examinations for duplicity. A brief summary
and statistical analysis of the contents of the catalog follow.
Introduction
The "Fourth Catalog of Interferometric Measurements of Binary Stars" began in
1982 as an internal database at the Georgia State University Center for High
Angular Resolution Astronomy (CHARA), tabulating binary star observations made
using the technique of speckle interferometry by that group's speckle camera.
The "Speckle Catalog" soon grew to encompass other published speckle efforts,
then all published astrometric and photometric data for binary stars (and single
stars observed in duplicity surveys) obtained by other high angular resolution
techniques (lunar occultations, adaptive optics, eyepiece interferometry,
Hipparcos, etc.) as well. This extended the catalog's baseline of observations
back by nearly a century, to the efforts of Schwarzschild & Villiger (1896).
Results of surveys based on various infrared speckle or imaging techniques were
later added, as well, even though some of these don't really qualify as "high
resolution".
Two printed editions were published in the 1980's (McAlister & Hartkopf 1984,
1988), and web versions have been available since the early 1990's (Hartkopf et
al. 2001a, 2001b). After the speckle efforts at CHARA were suspended in the
late 1990's (in order to devote more resources to their long-baseline
interferometry project) one of the authors (WIH) transferred the catalog (still
nicknamed the "Speckle Catalog" in honor of its origins) to the U.S. Naval
Observatory, whose own speckle efforts had begun earlier in the decade.
Catalog Description
Although the catalog is updated regularly, statistics are updated on only an
occasional basis. The table below summarizes the contents of the catalog as of
9 January 2018. In addition to the astrometric totals presented here, the
catalog includes 73,894 observations of photometric data only. Figures 1 - 3 of
the web page illustrate the distribution of catalog data with time, separation,
and declination, respectively.
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Fourth Interferometric Catalogue Statistics (as of 09 January 2018)
Number of resolved stars: 66,225
Number of never-resolved stars: 27,330
Total number of stars: 93,555
Median separation 0".89
Breakdown of data by method:
resolved unresolved total
Tycho 40,871 1,001 41,872
Hipparcos 13,880 16,798 30,678
USNO Speckle 22,294 4,758 27,052
CHARA Speckle 18,527 6,479 25,006
Other speckle, AO, etc 31,686 14,466 46,152
Eyepiece interferometry 3,085 700 3,785
Occultation 1,825 770 2,595
Multi-aperture interferometers 3,276 1,053 4,329
Hubble 2,040 3,638 5,678
Other techniques 25,582 43,126 68,708
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TOTAL 163,066 92,789 255,855
Of the resolved total, 2,473 are vector separations (from either
occultations or one-dimensional IR speckle).
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The catalog is divided into 24 one-hour right ascension bands, with names
int4_00.txt, int4_01.txt, etc.
Entries for each system are comprised of two parts: an identification line
containing designations from various catalogs, followed by individual measures
sorted in order of observation date (see the file int4_format.txt). Major
changes with this version include coordinates to 0.01s in RA and 0".1 in DEC,
improvements in the formatting of filter information to allow longer
wavelengths, and the addition of technique codes. The ID line format was changed
slightly in July 2007 to allow additional space for long names (e.g., 2MASS
designations).
Each observation includes a reference code linked to a reference file (see
int4_references.txt). Similarly, systems having notes are flagged with links
to file int4_notes.txt. An additional change in July 2007 provided links to the
Sixth Orbit Catalog for pairs with published visual or astrometric orbits.
A common notes file is used for all USNO double star catalogs (WDS, plus
the Interferometric and Orbit catalogs). As a result, the notes file will
include systems in addition to those in this catalog. Also, because the
notes file is much larger, it has been divided into 24 smaller files for
faster linking to the individual catalog measurements files.
Your comments regarding either style or substance are welcome. Please report
any errors you run across in the catalog to dsl@ad.usno.navy.mil .
References
Anderson, J.A. 1920, ApJ 51, 263
Hartkopf, W.I., Mason, B.D., McAlister, H.A., Turner, N.H., Barry, D.J., Franz,
O.G., & Prieto, C.M. 1996 AJ, 111, 936
Hartkopf, W.I., McAlister, H.A. & Mason, B.D. 2001a, Third Catalog of
Interferometric Measurements of Binary Stars, CHARA Contrib. No. 4,
http://www.ad.usno.navy.mil/wds/int3.html
Hartkopf, W.I., Mason, B.D., Wycoff, G.L., & McAlister, H.A. 2001b, Fourth
Catalog of Interferometric Measurements of Binary Stars,
http://www.ad.usno.navy.mil/wds/int4.html
Horch, E.P., Franz, O.G., & Ninkov, Z. 2000, AJ 120, 2638
McAlister, H.A. & Hartkopf, W.I. 1984, Catalog of Interferometric Measurements
of Binary Stars, CHARA Contrib. No. 1
McAlister, H.A. & Hartkopf, W.I. 1988, Second Catalog of Interferometric
Measurements of Binary Stars, CHARA Contrib. No. 2
Merrill, P.W. 1922, ApJ 56, 40
Schwarzschild, K. & Villiger, W. 1896, Astr. Nach. 139, 353