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XID II: Statistical Cross-Association of ROSAT Bright Source Catalog X-ray Sources with 2MASS Point Source Catalog Near-Infrared Sources
The 18,806 ROSAT All Sky Survey Bright Source Catalog (RASS/BSC) X-raysources are quantitatively cross-associated with near-infrared (NIR)sources from the Two Micron All Sky Survey Point Source Catalog(2MASS/PSC). An association catalog is presented, listing the mostlikely counterpart for each RASS/BSC source, the probability Pid that the NIR source and X-ray source are uniquelyassociated, and the probability P no-id that none of the2MASS/PSC sources are associated with the X-ray source. The catalogincludes 3853 high quality (P id>0.98) X-ray-NIR matches,2280 medium quality (0.98 >= P id>0.9) matches, and4153 low quality (0.9 >= P id>0.5) matches. Of the highquality matches, 1418 are associations that are not listed in the SIMBADdatabase, and for which no high quality match with a USNO-A2 opticalsource was presented for the RASS/BSC source in previous work. Thepresent work offers a significant number of new associations withRASS/BSC objects that will require optical/NIR spectroscopy forclassification. For example, of the 6133 P id>0.92MASS/PSC counterparts presented in the association catalog, 2411 haveno classification listed in the SIMBAD database. These 2MASS/PSC sourceswill likely include scientifically useful examples of known sourceclasses of X-ray emitters (white dwarfs, coronally active stars, activegalactic nuclei), but may also contain previously unknown sourceclasses. It is determined that all coronally active stars in theRASS/BSC should have a counterpart in the 2MASS/PSC, and that the uniqueassociation of these RASS/BSC sources with their NIR counterparts thusis confusion limited.
| New GCVS Versions for Three Southern Constellations
We are currently working on a version of the General Catalogue ofVariable Stars (GCVS) revised taking into account the new dataaccumulated since the 4th GCVS edition. A draft new version will bereleased for each constellation as soon as the work for theconstellation is finished. It will contain all stars of the 4th GCVSedition plus a complete catalogue of the stars added to the GCVS in theName Lists of Variable Stars Nos. 67 - 78. Now we are ready for thefirst release, containing more than 1300 variable stars in theconstellations of Antlia, Ara, and Telescopium. When preparing therelease, we actively used modern data-mining possibilities to improvevariability types and light elements. This paper introduces the firstrelease of the new GCVS version and presents new results (types, lightelements), based mainly on data mining, for 213 stars.
| New Estimates of the Solar-Neighborhood Massive Star Birthrate and the Galactic Supernova Rate
The birthrate of stars of masses >=10 Msolar is estimatedfrom a sample of just over 400 O3-B2 dwarfs within 1.5 kpc of the Sunand the result extrapolated to estimate the Galactic supernova ratecontributed by such stars. The solar-neighborhood Galactic-plane massivestar birthrate is estimated at ~176 stars kpc-3Myr-1. On the basis of a model in which the Galactic stellardensity distribution comprises a ``disk+central hole'' like that of thedust infrared emission (as proposed by Drimmel and Spergel), theGalactic supernova rate is estimated at probably not less than ~1 normore than ~2 per century and the number of O3-B2 dwarfs within the solarcircle at ~200,000.
| Catalog of Galactic OB Stars
An all-sky catalog of Galactic OB stars has been created by extendingthe Case-Hamburg Galactic plane luminous-stars surveys to include 5500additional objects drawn from the literature. This work brings the totalnumber of known or reasonably suspected OB stars to over 16,000.Companion databases of UBVβ photometry and MK classifications forthese objects include nearly 30,000 and 20,000 entries, respectively.
| Study of Neglected Variable Stars Classified as Type II Cepheids
Four variable stars classified as Type II Cepheids have been studiedpartly based on new photometry and the Hipparcos photometric data. Thecorrect period is derived for V341 Ara and NW Pav and it is pointed outthat RR Mic and V1711 Sgr do not belong to Type II Cepheids, insteadthey may be semi-regular variables. The cycle length of theirvariability is also determined.
| An Extension of the Case-Hamburg OB Star Surveys
We have extended the Case-Hamburg OB star surveys to b = +- 30 degreesfor l = +- 60 degres using the Curtis Schmidt telescope and 4 degreeobjective prism at the Cerro Tololo Inter-American Observatory. Acatalog of 234 OB stars and other objects with peculiar spectra ispresented along with finding charts for those objects too faint to beincluded on the BD or CD charts. (SECTION: Stars)
| Southern Cepheid Photometry.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJS....6..253I&db_key=AST
| Le type de population des céphéides galactiques; critères de distinction des types et catalogue
Not Available
| Bearbeitung des Lichtwechsels von 75 kurzperiodischen veranderlichen Sternen zwischen 25 und 90 sudlicher Deklination.
Not Available
| 71 new variable stars in Harvard Maps Nos. 9, 12, 21, 48 and 51
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| Takýmyýldýz: | Sunak |
| Sað Açýklýk: | 16h57m41.51s |
| Yükselim: | -63°12'38.4" |
| Görünürdeki Parlaklýk: | 10.648 |
| özdevim Sað Açýklýk: | -46.6 |
| özdevim Yükselim: | -82.5 |
| B-T magnitude: | 10.686 |
| V-T magnitude: | 10.652 |
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