--- published in Webb Society double star circluar no 19 http://www.webbdeepsky.com/dssc/dssc19.pdf Common Proper Motion Pairs and other Doubles Found in Spectral Surveys - 1. Stephenson dwarfs and PG stars Brian Skiff Lowell Observatory 1400 West Mars Hill Road Flagstaff AZ 86001-4499 USA bas@lowell.edu Introduction For several years I have worked to obtain accurate coordinates for stars appearing in numerous large spectral surveys. These surveys contain much valuable information for stars fainter than the HD catalogue. The results have been compiled into a bibliographic catalogue, presently containing over 400,000 entries. The file can be queried by coordinates or star-name using the Strasbourg VizieR catalogue service; the whole file can also be downloaded in bulk (cf. {\tt http://cdsarc.u-strasbg.fr/viz-bin/Cat?B/mk}). As part of the work in identifying the stars, I occasionally notice either obviously related companions, or nearby stars possibly confused with the star of interest, or sometimes mentioned by the compilers of the spectral surveys. In general the companions are not noted unless they are clearly physical, though in the present list several optical pairs are reported for other reasons. The present batch includes pairs noticed principally in two publications. The first is a survey for K- and M-type dwarf stars of small proper motion by C. Bruce Stephenson (1986a). These stars now have the SIMBAD acronym StKM 1-nnnn, and includes some 2200 entries. Second is a survey for uv-bright white dwarfs and hot subdwarfs by Richard Green (Green et al 1986) mostly in the north galactic cap. This list of nearly 1900 objects, known as the Palomar-Green survey, has received much astrophysical follow-up; the star-names have the acronym PG hhmm+ddd, where the RA is shown truncated to 1m of time, followed by the Declination rounded to 10'. Completed lists for these papers are available at the Lowell ftp area: {\tt ftp://ftp.lowell.edu/pub/bas/starcats/stephKM1.dat} {\tt ftp://ftp.lowell.edu/pub/bas/starcats/pg.dat} ...which are flat-text files of about 170Kb and 120Kb, respectively. Working methods Both components of the pairs are not necessarily present in various on-line catalogues, or if present, no proper motions are available. So it is not simply a matter of trawling through databases to extract stars with similar motion. Instead the stars have to be examined individually on digitized sky survey images, and the companions sought one-by-one based on considerations of the statistics of color, spectral type, and motions. While preparing the Stephenson catalogue, I examined carefully only stars either mentioned by him as being double, or stars where some confusion in identification arose from the astrometric catalogues as the result of there being multiple entries in close proximity. Thus some of the pairs listed here are not physical. I have since found many more very good physical binaries in this list and a related one by the same author (Stephenson 1986b), but these will be published later. In any case, only a small fraction of the 4000+ stars involved have been examined for companions. There are many more to be found in these lists. The Palomar-Green source coordinates are often poor, so recovery required examining every star on image cutouts. Luckily the stars have much coverage in the Sloan Digital Sky Survey (SDSS). Thus it was possible to use images and catalogues from that survey to examine the stars at comparatively high angular resolution and also to obtain accurate magnitudes and colors for these faint objects. Throughout this process I examined images from the traditional digitized sky surveys from Schmidt plate-scans in several colors (and both POSS-I and POSS-II scans in the north), as well as images from the 2MASS near-infrared survey, and SDSS images. All of these are served by the Goddard SkyView utility: http://skyview.gsfc.nasa.gov/cgi-bin/query.pl ...which provides images from clear across the electromagnetic spectrum. In general I selected cut-outs just 0.03 x 0.03 degrees (2'x2') in area, but sometimes as large as 4'x4'. To be able to see the faintest data in the images yet preserve the saturated highlights as much as possible, I choose the `Stern Special' color table, the most useful of many candy-stripe color schemes available at SkyView. The SkyView images are displayed in sequence, and the photometric color information is used along with the sequence of dates to assess the likelihood of a companion being physical. Having the spectral data at hand is obviously convenient. Once candidate pairs are identified, additional information is sought in the complete VizieR listing and in SIMBAD, the bibliographic database. Even the SIMBAD + VizieR combination often uncovers less than half of what is actually in the literature due to the incomplete object-wise indexing of journals, and because many published catalogues and data-tables are unavailable in machine-readable form (cf. Andernach 2009). This is the rationale for working on the spectral surveys in the first place. Coordinates and differential astrometry Since the point of this effort is to obtain accurate coordinates for the stars (not to find doubles!), I usually work with one or more Web browser windows looking at VizieR. Depending on the sort of stars to be examined (magnitude-range, spectral type, large proper motion or not), I will select a number of catalogues to be queried instead of the entire database; this speeds up the process and displays the information most of interest. The most obvious catalogue to be queried of course is the WDS itself, a fresh copy of which is now made each week. Thus the latest results can be compared with potential new pairs. Since VizieR also includes my own comprehensive database (updated a few times each year), this helps move the process along by providing coordinates and magnitudes considered in detail prevously. A certain lapidary, recursive improvement in the VizieR catalogues results from this procedure. Apart from a single visual-micrometer observation, already published in this journal, all the relative astrometry presented here was obtained from a substantial list of astrometric catalogues collected in VizieR. These are specified for each entry in the table in the column `source'. The acronyms and descriptions of the catalogues are as follows: AC2000 is the final re-reduction of the complete Astrographic Catalogue. This was published by the USNO-DC (Urban et al 1998), and can be searched in VizieR. It includes stars as faint as mag 13 in some regions. The principal value, of course, is providing astrometry for fairly close pairs at the earliest available epoch, typically about 1900. For stars measured from multiple images/plates, the differential astrometry is often good to 0".2. This is amply demonstrated for the wide common-motion pairs here. USNO-A2.0 in the north this provides astrometry for at least moderately-wide pairs at the epoch of the POSS-I plates, typically 1950 - 1956 (Monet et al 1998). Usually the plate-scanning breaks down below about 10" separation (only 150 microns on the original plates) for stars of intermediate brightness. Stars are saturated brighter than around mag 12-13, which compromises the astrometry for brighter stars. Typical errors in the differential astrometry are around 0".3, but can be 1"-2" for bright stars (and thus skipped over here). It is the relatively early epoch in the north that lets the catalogue retain its value for doubles, notably for helping show that pairs have demonstrably common motion when not present in AC2000. USNO-B1.0 is the USNO-A2.0 follow-on catalogue based on the plate-scans at USNO-Flagstaff, and gives positions and proper motions (Monet et al 2003). Unfortunately some care is necessary in using it: there are vast numbers of mis-matched stars from the various epochs included, so that many of the proper motions are simply wrong, as are the positions. B1.0 can occasionally come in useful if there is a way to verify the links among the stars via other catalogues. The positions are for epoch 2000.0, with proper motion applied to that date, though sometimes single offsets can be found for the epoch of one of the Schmidt plates. Steve Levine (2005) has shown that 99.9 percent of the large-motion stars in USNO-B1.0 are not real. GSC-ACT is an improved version of the original GSC prepared in 1999 by astronomy-software author Bill Gray (`Guide'). He re-reduced the coordinates plate-by-plate against the ACT catalogue (an early follow-on to the Tycho-1 catalogue that was used for USNO-A2.0), which removed the substantial zonal and radial plate-errors of the original GSC-1.1. A similar revision (GSC-1.2) was prepared by the Space Telescope Science Institute, but not made public until GSC-ACT was completed. Since the astrometry comes from single plates, there is some uncertainty in the results, typically about 0".3. Again, having these sometimes-soft results at an intermediate epoch (about 1980) can still be very useful. Bill Gray has provided some details of the catalogue construction at: {\tt http://www.projectpluto.com/gsc\_act.htm}). Rigorous independent external tests were made by others showing the dramatic improvement in the astrometry. Importantly, the GSC-ACT data are closely tied to the Hipparcos ICRF reference frame, so no rotation is necessary for doubles in relation to other catalogues (all the others here are also on the ICRF). GSC-2.3 this catalogue was produced by the STScI catalogues branch mainly from the POSS-II and southern UK Schmidt plates (Lasker et al 2008). For wider pairs it provides an intermediate epoch measurement different from GSC-ACT, and usually reliable to ~0".2. UCAC2 is currently the best all-sky (nearly) astrometric reference catalogue (Zacharias et al 2004). In particular it includes results from Tycho-2 and all its ~150 antecedents as well as new data from the UCAC astrograph and from Schmidt plates. As a true astrometric reference catalogue, it omits crowded stars, close doubles, and anything problematic. It is thus not an inventory of the sky, as are USNO-A2.0 etc, but is instead a high-precision astrometric network. Coordinates are presented for epoch and equinox 2000, derived (not observed) from the mix of astrometry; I have thus rounded the epoch to a single decimal to indicate this. Typical differential errors for double stars are only a few hundredths of an arcsec. Doubles are resolved down to about 6" separation, dependent on magnitude and sky-location. Though it extends from the south pole to only about +50 Dec, the data are distinctly superior to... UCAC3 though it covers the entire sky, much has been left out of this catalogue, and it is plagued with numerous systematic problems and quirks (Zacharias et al 2010). Like USNO-B1.0 it needs to be used with some care. As regards double stars, the proper motions can be completely spurious, with the two stars seeming to be exploding radially away from each other. The coordinates are often based on incomplete data (some regions omit Tycho-2, for instance!), and it appears that plate-errors from the Schmidt surveys have been introduced. See the paper by R{\"o}ser et al (2010) for an outline of only some of the problems. UCAC3 is generally avoided here, but sometimes adopted when the coordinates can be verified externally. In some parts of the sky, where there is coverage at intermediate epochs from astrograph plates, UCAC3 is as good or better than Tycho-2/UCAC2. CMC14 the 17cm Carslberg Meridian Circle, in its last productive incarnation, was used for a CCD astrometric/photometric sky survey extending from +50 to -30 Dec (Evans et al 2002). The resulting catalogue is an excellent source of single-epoch data for double stars as well as reliable Sloan r' photometry close to the standard sytem. For stars observed only once, differential astrometry errors can be as large as 0".3, but for those measured several times, the errors are below 0".1. In the table here I flag CMC14 entries with four or more observations, which ought to have high astrometric weight. ACR another CCD transit-circle of 20cm aperture, this time at the U.S. Naval Observatory's Flagstaff Station in Arizona (Stone et al 1999). This was used to produce a catalogue of faint stars near the celestial equator. The limited sky coverage restricts its use to just one pair here, but the astrometry has high internal precision, below 0".1, and as faint as mag 17. A tiny magnitude-dependent error is reported by Zacharias et al (2004). This catalogue has been overlooked as a source of common-motion pairs. Bordeaux a third 20cm CCD meridian-circle at Bordeaux Observatory was used to build a catalogue of faint stars between about +11 and +18 Dec down to mag 15 (Ducourant et al 2006). These new data were combined with scans of the Bordeaux zone of the Astrographic Catalogue and Schmidt-plate data to provide proper motions. The data seem to be somewhat less good than the Carlsberg instrument, but are nevertheless useful in the relevant zone (only a single use here). The catalogue is another one overlooked as a source of common-motion pairs. 2MASS arguably the most useful astronomical project to have been completed since the first Palomar sky survey (Cutri et al 2003). This provides astrometry with errors well below 0".1 (both absolute and relative) for the entire sky, and near-IR JHK photometry. The mean epoch is about 1999, and pairs are resolved down to 2" in favorable circumstances. The images available through Goddard SkyView permit the detection of very red (low mass) companions near very bright stars. The relatively recent epoch allows common-motion stars to be recognized down to at least 50 mas/year by comparison with POSS-I or other Schmidt surveys. DENIS an independent near-IR survey conducted by a European consortium using the 1-m telescope at ESO-La Silla, Chile (DENIS consortium 2005). This was started prior to 2MASS, and was intended to cover the southern sky in Sloan i, and J and K filters. Unfortunately the survey was not completed, so coverage is patchy. The astrometric reduction was against USNO-A2.0, so the absolute astrometry is somewhat soft (~0".5). However, even the differential astrometry from the same field scans can sometimes inexplicably be rather poor (~0".3). DENIS nevertheless can provide useful confirmation of pairs at one or more recent epochs. LSPM the Lepine-Shara proper-motion catalogue (Lepine \& Shara 2005) shows separate positions for many pairs with large proper motion (>0".15/year). Their positions were derived from the proper-motion determined by matching Schmidt plate-scans and the 2MASS catalogue and applied to the 2MASS source position to bring it to epoch/equinox J2000. As with UCAC2, the epoch is rounded in the table to show that the relative astrometry is derived, not observed for that date. Uncertainties on the data are ~0".2. SDSS DR7 this is the most recent version of the global Sloan survey, which includes a mammoth object catalogue, and images from the Goddard SkyView facility (Abazajian et al 2009). The data were taken with a 2.5-m telescope in New Mexico. Whereas the pixels in the common digitized sky surveys from Schmidt scans and 2MASS are either 1".7 or 1".0, the SDSS pixels are only 0".4 square. This makes a significant difference in recognizing and measuring pairs. I have measured pairs on the images down to 0".7 separation. One need only examine some of the 1" - 2" pairs noted here on DSS, 2MASS, and SDSS images to see the dramatic difference. The images (and photometric data) saturate at mag 15, so in general SDSS is for faint stars only. Even so, the saturated images of mag ~10 stars contain much information, and the tiny pixels mean that very faint, close companions to such stars can be picked out. Another valuable feature is that the images were taken in five filters from the violet out to nearly 1 micron. This means that composite binaries such as the white-dwarf/M-dwarf pairs listed here are very easy to distinguish. For the PG star coordinates I have adopted the equinox/epoch J2000 positions from this catalogue shown by VizieR, which accounts for the proper motion derived by comparison with USNO-B1.0 plate data. The relative astrometry is for the epoch of the Sloan drift-scans, also tabulated in VizieR. Since the data were taken with a large-aperture telescope at favorable image scale, the differential astrometry is very accurate. Further details about all these catalogues can be found in the `ReadMe' pages associated with each VizieR catalogue in addition to the references cited. The epoch of observation is shown as year-fractions by VizieR for most of the catalogues just mentioned, as usual in double-star observing. 2MASS shows the UT calendar date, while DENIS gives the JD, and CMC14 gives the JD-since-start-date. These nuisances were converted to UT as needed, and the Besselian year-fraction read from the USNO ''Explanatory Supplement" table for same. Some additional catalogues available in VizieR can come into play in various regions of the sky, but it is not necessary to mention these now. The data table should be mostly self-explanatory. The first column shows the WDS name already assigned to the pairs. The coordinates are given to 0".1 precision, as is now used in the WDS, and apply nearly always to the primary star for both epoch and equinox J2000. The column `s' following the position shows a single-letter code for the source of the position: b USNO-B1.0 L LSPM M 2MASS S SDSS DR7 T Tycho-2 (or other HIP/Tyc-based catalogues) U UCAC2 (occasionally UCAC3) These are not chosen at random, but are the `best' for any specific case. The default is to adopt UCAC2 for brighter uncrowded stars, and SDSS or 2MASS for the fainter stars. The magnitudes are standard V magnitudes obtained from a variety of sources, including published photoelectric or CCD photometry, the ASAS-3 or TASS MkIV databases, SDSS data transformed to standard V, rough adjusted averages from the Schmidt surveys, etc. It is often the case that only the combined magnitude is available; component values were then obtained by adopting delta-mags from (for instance) CMC14 or UCAC3. (One of the best features of UCAC3 may be the photometry!) Below its saturation regime, the SDSS photometry is reliable at the few-percent level down to mag 21. The relative astrometry then follows in the familiar format, with the source of each observation at the end of each line. A note is given for every entry at the bottom of the data-table. This mainly provides a `real' (SIMBAD) name for the star, since they all come from some published paper. Other relevant details are given about the apparent motion, spectral types, and so on. Acknowledgements Brian Mason (USNO) accepted these doubles some years ago on the skimpiest of evidence, fuller details for which are herewith supplied. I appreciate comments and encouragement from him and from John Greaves about the preparation of this report. Francois Ochsenbein (CDS-Strasbourg) has always been helpful as regards large on-line catalogues. References Abazajian, K. N., and 203 co-authors, Astrophys. J., Suppl. Ser, 182, 543, 2009 Andernach, H., Data Sci. J., 8, 41, 2009; available as astro-ph preprint {\tt http://arxiv.org/abs/0901.2805} Cutri, R. M., and 24 co-authors, IPAC/California Institute of Technology, 2003 DENIS consortium, 2005, {\tt http://cdsweb.u-strasbg.fr/denis.html} Ducourant, C., and 11 co-authors, Astron. Astrophys., 448, 1235, 2006 Evans, D. W. Irwin, M. J., and Helmer, L., Astron. Astrophys., 395, 347, 2002; see also: {\tt http://www.ast.cam.ac.uk/\~dwe/SRF/cmc14.html} Farihi, J., Becklin, E. E., and Zuckerman, B., Astrophys. J., Suppl. Ser., 161, 394, 2005 Green, R. F., Schmidt, M., and Liebert, J., Astrophys. J., Suppl. Ser., 61, 305, 1986 Lasker, B. M., and 25 co-authors, Astron. J., 136, 735, 2008 Lepine, S., and Shara, M. M., Astron. J., 129, 1483, 2005 Levine, S. E., Astron. J., 130, 319, 2005 Mason, B. D., Hartkopf, W. I., Wycoff, G. L., and Wieder, G., Astron. J., 134, 1671, 2007 Monet, D. G., and 15 co-authors, U. S. Naval Observatory, 1998 Monet, D. G., and 27 co-authors, Astron. J., 125, 984, 2003 R{\"o}ser, S., Demleitner, M., and Schilbach, E., Astron. J., 139, 2440, 2010; available as astro-ph preprint {\tt http://arxiv.org/abs/1003.5852} Stephenson, C. B., Astron. J., 91, 144, 1986a Stephenson, C. B., Astron. J., 92, 139, 1986b Stone, R. C., Pier, J. R., and Monet, D. G., 1999, Astron. J., 118, 2488, 1999 Urban, S. E., Corbin, T. E., Wycoff, G. L., H{\/o}g, E., Fabricius, C., and Makarov, V. V., 1998, Astron. J., 115, 1212, 1998 Vyssotsky, A. N., Astron. J., 61, 201, 1956 Weis, E. W., Astron. J., 105, 1962, 1993 Zacharias, N., and 7 co-authors, Astron. J., 127, 3043, 2004 Zacharias, N., and 29 co-authors, Astron. J. 139, 2184, 2010 Zuckerman, B., and Becklin, E. E., Astrophys. J., 386, 260, 1992 ******************************************************************************* Thanks for allowing us to go over the draft. I also appreciate your letting me publish these pairs in the DSSC, and given my quirky view of double stars, I hope they'll be of interest to your readers. I have had the comment from Dick Harshaw that he appreciated the glosses on the various astrometric catalogues. Later lists (I promise!) will include pairs that are more interesting than the ones here. I like to think that the comments in the notes will engender interest as well. I haven't been at all sure how much mark-up you wanted us contributors to do, either doing as much as possible to make your life easier, or none at all to make your life easier! There are various inconsistencies or non-standard usage I put in that may not matter much unless you decide to make things more formal and adopt some standard format ("Chicago Manual of Style", or in the UK maybe it's the "Oxford Book of Style" or something...). I have this terrible modern thing of not putting a period at the end of abbreviations, so there are etc, viz, et al, and others that in LaTex probably should be italicized _and_ have a period at the end. Since it looks as though you generally just took what I sent as-is, I'll try to do things more correctly in the future. Another non-standard usage on my part is in the notes section, where I have all the sentences starting in lower-case letters. If this bothers you I can change it in the future. Since a lot of them are ending up as a substantial paragraph, rather than quick comments, perhaps the proper way is to do it normally. Sorry. Similarly, the Web URLs that get cited probably should all have the {\tt} brackets around them. Even better, of course, would be to have real hyperlinks in the version at the Webb Society Web page, so you could get papers from ADS or elsewhere just by clicking on the link. Probably all of that is inconsequential for now. Okay, since this was the first of the series, there are a lot of little things that need tweaking. In anticipation of later lists, I would like to change the paper title to: Common Proper Motion Pairs and other Doubles Found in Spectral Surveys - 1. Stephenson dwarfs and PG stars The switch from a Roman numeral to an Arabic one is so that reader's ability to read the former will not need to be tested later on --- Superbowl XXXVIII! Then a subtitle to give the general nature of the stars included. Other minor details: In the description for the GSC-ACT, omit the close-paren following the URL. (my typo) In the description for UCAC2 the phrase "its 150 antecedents" should be "its \~150 antecedents". The description header given as "DSS DR7" should of course be "SDSS DR7". The quotation marks for "Explanatory Supplement" should properly be ``Explanatory Supplement". In the references, the URLs in the citations for Andernach, for Evans et al, and for Roser et al should be put in brackets {\tt ... }. In Table 1, it should look a lot neater to have the coordinates header be: & \multicolumn{2}{c}{RA\quad (J2000)\quad Dec} & I used this in the series of IBVS flyers I did with Timo Kinnunen giving big lists of coords for variable stars. See for example: http://www.konkoly.hu/cgi-bin/IBVS?4879 ...particularly the pdf file, to see what this looks like. The advantage (at least in what I sent to them, not as posted by the IBVS folks!) was that you get rid of the redundant (J2000) --- is the RA gonna be different than the Dec?! --- and also in principle the RA and Dec can be run closer together on the page. My column `s' ought to come closer to the end of the Dec also. In the data table, you can make the estimated magnitudes, where I put them without decimals, to have the .0 end-figure just to keep the column lined-up. You could also simply left-justify that column. This applies to the secondaries for: WDS 08159-4034 WDS 03276-7251 WDS 12445-0119 BC WDS 16320+0800 In the notes it would be nice to have a bit of a gap between the alias and the start of the text. Is this an em-space (two em-spaces?) or something like that in LaTeX? In the notes there needs to be a blank line between the entries for 15019+3023 and 15397+6055. In the entry for 16012-0052, "weavelengths" should of course be "wavelengths". All for now. Let me know if you have questions. ******************************************************************************* WDS 16163-0139 CD a likely optical pair in the field of and unrelated to Struve 2031 = HD 146433. the 1987 visual micrometer measurement, using the Lowell 60cm Clark refractor, was published previously in Webb Circular no 8 (2000), and shown here for completeness. WDS 08159-4034 AB,C WDS 08159-4034 AB,D the AB components are the close pair Rst 2544 = CD-40 4045. stars C and D are unrelated, obscured M giants in the background, noticed while working on identifications for a far-red spectral survey. the V magnitudes for the M giants are merely estimates, but since they are both very red and strongly reddened, they are brighter than the Rossiter double in the near-infrared. the astrometry was found by taking differences between UCAC2 (for AB) and 2MASS for the two red stars, epoch 2000 assumed since no relative motion is expected for these very distant objects. WDS 01142-0847 = StKM 1-127 this was reported as a (single) K7 dwarf by Stephenson, but is a pair of small proper motion. there is no apparent relative motion since the epoch of POSS-I (1951.911). WDS 01347+0502 = StKM 1-169 another type K5 dwarf of small proper motion reported by Stephenson that was found to have a fainter common-motion companion. in 2MASS images the primary is slightly oval while the secondary is not, suggesting it is perhaps a near-equal ~1" pair, with the companion located in about pa 210. WDS 04012+1206 = StKM 1-439 previously reported by Luyten as the common-motion pair LP 474-2164/2165 in ``Proper Motion Survey with 48-inch Schmidt Telescope, LIX," Univ of Minnesota, 1981, but not shown in the WDS. the combined spectral type is M0 according to Stephenson. WDS 08456+2801 = StKM 1-723 an optical pair, with types given by Stephenson as K5 + M0; however, the companion is not red, so that type is wrong. WDS 11507+3312 = StKM 1-974 a common-motion pair of combined type M1 according to Stephenson. some DSS, Sloan, and 2MASS images show a third star close on W side of A comp in about pa 250. the 7" pair was not resolved by Lepine \& Shara in their proper-motion survey. WDS 13594+1138 = StKM 1-1110/1111 common-motion pair with spectral types K4 + K4 per Stephenson. WDS 15111+4424 = StKM 1-1219/1218 this is an optical pair involving BD+44 2434 and AG+44 1227. the fainter star has large proper motion, and is currently approaching the primary. the spectral types are K4 + K5V in the Stephenson survey. WDS 15223+0626 = StKM 1-1236 spectral types K4 + K: according to Stephenson. WDS 16291+0514 = StKM 1-1343 an equal, large common-proper-motion pair not resolved in the Lepine \& Shara catalogue. the Stephenson types are M0: + M0:. WDS 16348+0430 = StKM 1-1360/1361 an apparently common-motion pair, though sky-motion is modest; spectral types K4 + K4 in Stephenson. WDS 17056+0530 = StKM 1-1428/1427 a wide optical pair from the Stephenson survey, whose types are K4 + K4/5. the WDS also shows a follow-up speckle observation from 2006.596 by Mason et al (2007). WDS 21235+2125 = StKM 1-1887/1886 another wide optical pair in the Stephenson survey, where the types are given as K3: + K4. the slightly fainter component was inadvertently listed again by Stephenson (1986b) with the designation StKM 2-1518. WDS 21245+1003 = StKM 1-1889/1890 a wide optical pair assigned the types K3/4 + K4/5 by Stephenson. WDS 05334-4923 = HD 37106 the primary is the unconfirmed 0".1 Hipparcos binary HDS 732. spectral types are F6V (Houk) and G0 (`Cape Faint' catalogue of 1939), though the latter is too early --- it is probably a mid-K dwarf per delta-mag and 2MASS colors. WDS 02109-4604 = CD-46 644 the primary has spectral type K3IVe; the faint companion is a mid-M dwarf. WDS 03276-7251 = CPD-73 219 = NSV 1174 the primary is a chromospherically- active K0IV that is also an eclipsing double-lined spectroscopic binary. the companion is an M dwarf. WDS 02444+1057 = MCC 401 = StKM 2-233 the primary is a K5/M0 dwarf recognized as far back as Vyssotsky's (1956) survey. the previous AB companion, PLQ 35, is optical, but a third star, listed here, shares common proper motion. the two stars were observed for UBVRI photometry by Weis (1993), who thus identified the cool companion originally. WDS 00250+3015 = PG 0023+299 the primary is a hot subdwarf (type sdB) whose significant proper motion makes the link with the companion clear. WDS 01138+1759 = PG 0111+177 the primary is a white dwarf having a K-dwarf companion. WDS 02385+0638 = PG 0235+064 the primary is a white dwarf; from its 2MASS J-K color, we can estimate that the companion is an early-M dwarf. WDS 03099+1505 = PG 0307+149 the primary is a white dwarf; the companion does not brighten up at long wavelengths, so is also relatively hot, but no spectrum is available. WDS 08414+1618 = PG 0838+165 the primary is an sdB subdwarf, while the companion is apparently a G-type main-sequence star. WDS 08487+1242 = PG 0845+129 another sdOB + M binary; the modest common motion is clear between the POSS-I plates and recent images, but the pair are resolved only in the Sloan catalogue. WDS 09078+3857 = PG 0904+391 this white dwarf has a faint M-dwarf companion that is likely to be physical. WDS 09186+1953 = PG 0915+201 the primary was assigned type DA2 in the Palomar-Green survey; the companion becomes graduallly brighter toward the red, and must be an M dwarf. WDS 09528+1821 = PG 0950+186 a white-dwarf/M-dwarf binary also previously reported by Zuckerman \& Becklin (1992). WDS 10180+0721 = PG 1015+076 another white-dwarf/M-dwarf binary; though slightly fainter in the visible, the primary is taken to be the more-evolved white dwarf component. Farihi et al (2005) also reported a more distant M dwarf, but the physical link is uncertain. WDS 11037+5851 = PG 1100+591 recorded as a blue star by Luyten (LB 1938), but the faint companion has been overlooked heretofore. the primary is evidently a blue subdwarf, while the companion is a K or M main-sequence star. WDS 11324-0821 = PG 1129-081 this was recognized as a binary in the original Palomar-Green survey and assigned spectral types sdBO + G; again the more-evolved subdwarf is taken as the primary. WDS 12445-0119 the B component is the white dwarf PG 1241-010 = Zuc 11, which has large proper motion; it is currently passing near an unrelated M dwarf of modest motion. a representative sep/pa is shown. the B component is a closer physical pair including a much fainter cool star. WDS 13079+0132 = PG 1305+018 a white dwarf with modest proper motion whose M-dwarf companion is clearly linked by inspection of the POSS-I plate-scans and newer images. the annual proper motion in RA is only about -80 mas/year, not -135 as shown by UCAC3, where the linkage is confused by the companion. WDS 13282+1632 = PG 1325+168 this close pair is resolved only in the SDSS catalogue. the significant motion compared with older plates makes the physical link certain. WDS 13413+3422 = PG 1339+346 the bluest of this mixed optical/cpm trio is taken as the primary. the distant M dwarf companion NW shares motion with the white dwarf. in recent decades the white dwarf has been passing close to a field M dwarf, so that all the astrometric data for component A derived from Schmidt plate-scans is compromised, i.e. a photocenter weighted by the bandpass of the plates. thus only the Sloan astrometry is reported. WDS 14121+4216 = PG 1410+425 this type DA4 white dwarf is the western star of a wide binary showing common proper motion. the companion is not red and may be a cooler degenerate star. WDS 15019+3023 = PG 1459+306 the type DA3 primary is the hot, evolved component of another white-dwarf/M-dwarf binary. though much fainter than the primary at visible wavelengths, the cool companion becomes much brighter in the near-infrared. WDS 15397+6055 = PG 1538+611 this hot B subdwarf is the northeastern component of a binary with a cool main-sequence star. WDS 16012-0052 = PG 1558-007 this sdB star has a faint late-type companion that comes up at longer wavelengths. the relative closeness means the available astrometry is poor except for the Sloan data. WDS 16054+4305 = PG 1603+432 the primary is a hot white dwarf showing a very faint common-motion companion on the deep, high-resolution Sloan images. the companion may itself be a cooler degenerate star. WDS 16320+0800 = PG 1629+081 the type sdBO primary is bright enough to appear in astrometric catalogues as far back as the Toulouse zone of the Astrographic Catalogue. both the magnitude for the secondary and the astrometry (both from SDSS DR7) are uncertain since the primary is overexposed in the Sloan data; a second date is discordant, and it is not obvious which, if either, is correct. WDS 16549+5420 = PG 1653+544 the hot sdBO subdwarf primary has very small proper motion, so the linkage with the cool companion SE is uncertain. WDS 16581+1031 = PG 1655+106 another hot sdBO star, and the companion is of intermediate color. two other brighter stars lie within 9", but are ignored here. WDS 23537+2006 = PG 2351+198 the primary was classified as a B-type horizontal-branch star in the Palomar-Green survey. from its photometric colors, the similarly-bright companion appears to be a G-type dwarf, and thus is almost certainly not related. ******************************************************************************* Name RA (J2000) Dec s Va Vb theta rho epoch source WDS 16163-0139 CD 16 16 22.21 -01 37 28.8 U 12.7 13.5 168.6 19.26 1953.518 USNO-A2.0 167.8 19.20 1980.232 GSC-ACT 165.3 18.9 1987.389 BSkiff visual micrometry 167.1 18.98 1989.285 GSC-2.3 166.6 18.99 1995.381 ACR 166.6 18.92 1999.230 2MASS 166.6 18.96 1999.36 DENIS, n=2 166.5 18.95 2000.0 UCAC2 166.5 18.93 2000.041 CMC14, n=4 WDS 08159-4034 AB,C 8 15 59.10 -40 34 07.6 U 10.4 15.0 147.7 3.26 2000.0 UCAC2 minus 2MASS WDS 08159-4034 AB,D 10.4 17.0 193.8 11.20 2000.0 UCAC2 minus 2MASS WDS 01142-0847 1 14 10.08 -08 46 57.6 M 13.0 13.0 249.9 4.11 1999.967 2MASS 250.2 4.22 2000.737 SDSS DR7 250.4 4.12 2003.728 CMC14 WDS 01347+0502 1 34 41.51 +05 01 47.2 U 11.8 13.0 131.4 16.86 1949.893 USNO-A2.0 131.2 17.37 1982.798 GSC-ACT 131.2 17.31 1983.689 GSC-ACT 131.0 17.45 1986.836 GSC-2.3 131.4 17.35 2000.646 2MASS 130.9 17.31 2000.646 CMC14 WDS 04012+1206 4 01 11.05 +12 05 54.1 U 12.3 12.8 93.4 5.55 1994.325 SDSS DR7 93.4 5.50 1997.756 2MASS 93.7 5.46 2001.531 CMC14 WDS 08456+2801 8 45 33.63 +28 01 18.0 U 12.8 13.9 213.3 24.96 1953.940 USNO-A2.0 213.9 22.21 1983.037 GSC-ACT 213.9 20.69 1998.090 2MASS 214.1 20.47 2000.0 UCAC2 214.0 20.34 2001.203 CMC14 WDS 11507+3312 11 50 43.04 +33 12 18.1 L 12.2 12.2 106.1 7.52 1998.186 2MASS 106.2 7.51 2000.0 LSPM 106.2 7.15 2002.969 CMC14 106.2 7.43 2004.362 SDSS DR7 WDS 13594+1138 13 59 25.90 +11 38 19.9 U 12.1 12.3 88.5 11.75 1982.300 GSC-ACT 88.4 12.06 1989.267 GSC-2.3 88.7 12.07 2000.0 Bordeaux 88.4 12.06 2000.230 2MASS 88.4 12.06 2000.424 CMC14, n=5 88.4 12.11 2003.245 SDSS DR7 WDS 15111+4424 15 11 03.71 +44 24 14.9 U 10.1 10.8 314.5 34.87 1893.291 AC2000 304.4 21.68 1955.232 USNO-A2.0 296.2 17.61 1982.390 GSC-ACT 296.7 17.41 1982.475 GSC-ACT 289.1 15.05 1999.394 2MASS 287.2 14.55 2002.783 CMC14, n=4 WDS 15223+0626 15 22 19.25 +06 26 26.3 M 11.4 11.4 264.8 9.34 1999.430 CMC14 265.3 9.34 2000.263 2MASS 265.1 9.39 2000.50 UCAC3 WDS 16291+0514 16 29 07.45 +05 14 11.4 L 12.0 12.0 333.2 7.51 2000.0 LSPM 333.5 7.49 2000.348 2MASS 333.6 7.46 2002.162 CMC14, n=6 WDS 16348+0430 16 34 49.07 +04 29 57.2 M 11.4 11.7 87.7 8.02 1999.389 CMC14 87.3 8.07 2000.348 2MASS 87.6 8.03 2000.61 UCAC3 WDS 17056+0530 17 05 37.88 +05 30 22.0 U 10.8 11.3 260.2 40.09 1954.342 USNO-A2.0 261.2 39.86 1982.478 GSC-ACT 261.3 39.65 1999.693 CMC14 261.3 39.62 2000.0 UCAC2 261.3 39.66 2000.359 2MASS WDS 21235+2125 21 23 32.22 +21 25 10.7 U 11.2 11.6 265.5 35.59 1954.520 USNO-A2.0 263.2 39.14 1999.862 2MASS 263.2 39.21 2000.0 UCAC2 263.2 39.31 2001.312 CMC14 WDS 21245+1003 21 24 32.42 +10 03 22.3 U 10.0 10.2 57.5 57.73 1951.577 USNO-A2.0 59.0 55.31 1983.841 GSC-ACT 59.3 54.15 2000.0 UCAC2 59.2 54.17 2000.334 2MASS 59.3 54.06 2001.394 CMC14, n=5 WDS 05334-4923 5 33 26.82 -49 22 40.4 T 7.2 11.0 321.9 32.50 1904.556 AC2000 322.1 33.21 1999.879 2MASS 322.0 33.61 2000.772 DENIS WDS 02109-4604 2 10 55.39 -46 03 58.7 U 11.2 15.5 290.7 21.62 1977.895 USNO-A2.0 290.3 21.45 1999.726 2MASS 290.5 21.48 2000.0 UCAC2 WDS 03276-7251 3 27 35.51 -72 50 55.2 U 11.0 16.0 36.8 28.88 1982.836 USNO-A2.0 36.6 28.71 1999.83 DENIS, n=2 36.8 28.89 2000.0 UCAC2 36.5 28.82 2000.164 2MASS WDS 02444+1057 AC 2 44 21.37 +10 57 41.1 U 11.2 15.3 106.8 20.72 1949.888 USNO-A2.0 107.4 20.85 2000.742 2MASS 106.8 20.92 2000.895 CMC14 WDS 00250+3015 0 25 58.96 +30 15 11.5 U 16.2 16.2 132.0 4.50 1997.909 2MASS 130.1 4.74 2002.435 CMC14 WDS 01138+1759 1 13 45.52 +17 58 50.1 M 16.0 16.1 214.9 4.62 2000.518 2MASS 215.4 4.57 2001.712 CMC14 215.2 4.76 2004.707 SDSS DR7 WDS 02385+0638 2 38 30.92 +06 37 59.9 M 15.5 16.1 342.1 7.27 1982.880 GSC-ACT 343.4 7.43 1990.733 GSC-2.3 344.4 7.43 2000.728 2MASS 342.9 7.49 2002.663 CMC14 343.7 7.53 2004.953 SDSS DR7 WDS 03099+1505 3 09 53.96 +15 05 22.0 B 15.2 18.8 186.2 10.11 1949.882 USNO-A2.0 184.1 10.31 1989.842 GSC-2.3 185.0 10.11 2000.0 USNO-B1.0 WDS 08414+1618 8 41 22.71 +16 17 34.3 U 15.5 15.5 107.9 10.81 1954.972 USNO-A2.0 108.5 11.06 1989.933 GSC-2.3 108.8 11.25 2000.0 UCAC2 109.6 11.05 2000.909 2MASS 109.3 11.03 2001.901 CMC14 109.5 11.04 2005.052 SDSS DR7 WDS 08487+1242 8 48 44.72 +12 41 47.8 S 16.5 17.5 96.6 2.44 2005.860 SDSS DR7 WDS 09078+3857 9 07 46.52 +38 56 43.7 S 16.4 20.0 29.9 5.26 2002.106 SDSS DR7 WDS 09186+1953 9 18 33.06 +19 53 07.9 S 16.5 19.7 252.6 2.29 2005.047 SDSS DR7 WDS 09528+1821 9 52 45.74 +18 21 02.9 S 15.7 16.9 101.1 1.30 2005.194 SDSS DR7 WDS 10180+0721 AB 10 18 01.52 +07 21 24.6 S 16.5 15.9 120.9 2.09 2002.120 SDSS DR7 WDS 10180+0721 AB,C 15.4 17.3 47.4 38.72 1955.224 USNO-A2.0 47.3 37.90 1991.269 GSC-2.3 47.2 37.63 2000.515 CMC14, n=6 48.1 37.81 2002.120 SDSS DR7 WDS 11037+5851 11 03 43.20 +58 50 32.8 M 13.3 19.7 284.1 4.27 1999.110 2MASS 282.7 4.27 2002.120 SDSS DR7 WDS 11324-0821 11 32 20.85 -08 21 22.3 S 16.5 16.0 120.0 6.63 1989.2 GSC-2.3 119.5 6.88 1994.266 SDSS DR7 122.6 6.85 2003.277 CMC14 WDS 12445-0119 AB 12 44 28.77 -01 19 09.0 U 14.4 15.2 344.3 11.51 2000.0 UCAC3 WDS 12445-0119 BC 12 44 28.57 -01 18 57.9 S 15.2 19.0 251.4 2.92 2000.116 SDSS DR7 WDS 13079+0132 13 07 54.52 +01 32 10.5 S 15.3 17.1 88.5 3.15 2000.340 SDSS DR7 WDS 13282+1632 13 28 14.29 +16 31 51.6 S 16.4 17.7 118.9 1.32 2005.416 SDSS DR7 WDS 13413+3422 AB 13 41 18.00 +34 21 54.6 S 15.9 15.6 210.7 2.53 2004.283 SDSS DR7 WDS 13413+3422 AC 15.9 16.7 296.6 20.31 2004.283 SDSS DR7 WDS 14121+4216 14 12 07.61 +42 16 27.5 b 16.0 18.4 102.0 13.65 1955.281 USNO-A2.0 100.6 13.67 1995.466 GSC-2.3 99.8 13.51 2000.0 USNO-B1.0 100.7 13.61 2003.226 SDSS DR7 WDS 15019+3023 15 01 56.33 +30 22 58.4 S 14.4 14.9 25.0 4.41 2002.15 UCAC3 25.2 4.44 2003.480 SDSS DR7 25.7 4.24 2003.728 CMC14 WDS 15397+6055 15 39 43.19 +60 55 00.8 S 15.2 15.4 199.1 3.20 1994.635 SDSS DR7 199.0 3.27 2004.453 SDSS DR7 WDS 16012-0052 16 01 14.00 -00 51 42.1 U 13.5 17.5 2.3 2.94 1998.561 DENIS, uncertain 2.4 2.11 1999.173 2MASS, uncertain 3.7 2.76 1999.216 SDSS DR7 WDS 16054+4305 16 05 21.15 +43 04 35.7 S 14.8 20.2 201.1 7.76 2002.437 SDSS DR7 WDS 16320+0800 16 32 01.36 +07 59 40.2 S 12.8 15.0 217.2 2.43 2005.362 SDSS DR7, uncertain WDS 16549+5420 16 54 54.16 +54 20 27.7 M 15.7 17.2 115.7 5.42 1999.353 2MASS WDS 16581+1031 16 58 07.94 +10 30 44.7 b 17.0 18.2 200.0 2.58 1994.545 SDSS DR7 WDS 23537+2006 23 53 44.77 +20 06 04.9 U 13.6 13.8 12.5 14.77 1954.652 USNO-A2.0 13.1 15.50 1982.804 GSC-ACT 13.0 15.78 1990.806 GSC-2.3 13.0 15.98 1998.750 2MASS 12.6 15.96 2001.674 CMC14, n=4