내용
사진
사진 업로드
DSS Images Other Images
관련 글
Speckle Observations of Binary Stars with the WIYN Telescope. VII. Measures during 2008-2009
Five hundred thirty-one speckle measures of binary stars are reported.These data were taken mainly during the period 2008 June through 2009October at the WIYN 3.5 m Telescope at Kitt Peak and represent the lastdata set of single-filter speckle observations taken in the WIYN speckleprogram prior to the use of the current two-channel speckle camera. Theastrometric and photometric precision of these observations isconsistent with previous papers in this series: we obtain a typicallinear measurement uncertainty of approximately 2.5 mas, and themagnitude differences reported have typical uncertainties in the rangeof 0.1-0.14 mag. In combination with measures already in the literature,the data presented here permit the revision of the orbit of A 1634AB (=HIP 76041) and the first determination of visual orbital elements forHDS 1895 (= HIP 65982).The WIYN Observatory is a joint facility of the University ofWisconsin-Madison, Indiana University, Yale University, and the NationalOptical Astronomy Observatories.
| Observations of Binary Stars with the Differential Speckle Survey Instrument. II. Hipparcos Stars Observed in 2010 January and June
The results of 497 speckle observations of Hipparcos stars and selectedother targets are presented. Of these, 367 were resolved into componentsand 130 were unresolved. The data were obtained using the DifferentialSpeckle Survey Instrument at the WIYN 3.5 m Telescope. (The WIYNObservatory is a joint facility of the University of Wisconsin-Madison,Indiana University, Yale University, and the National Optical AstronomyObservatories.) Since the first paper in this series, the instrument hasbeen upgraded so that it now uses two electron-multiplying CCD cameras.The measurement precision obtained when comparing to ephemeris positionsof binaries with very well known orbits is approximately 1-2 mas inseparation and better than 0fdg6 in position angle. Differentialphotometry is found to be in very good agreement with Hipparcos measuresin cases where the comparison is most relevant. We derive preliminaryorbits for two systems.
| A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)
The LSPM catalog is a comprehensive list of 61,977 stars north of theJ2000 celestial equator that have proper motions larger than 0.15"yr-1 (local-background-stars frame). The catalog has beengenerated primarily as a result of our systematic search for high propermotion stars in the Digitized Sky Surveys using our SUPERBLINK software.At brighter magnitudes, the catalog incorporates stars and data from theTycho-2 Catalogue and also, to a lesser extent, from the All-SkyCompiled Catalogue of 2.5 million stars. The LSPM catalog considerablyexpands over the old Luyten (Luyten Half-Second [LHS] and New LuytenTwo-Tenths [NLTT]) catalogs, superseding them for northern declinations.Positions are given with an accuracy of <~100 mas at the 2000.0epoch, and absolute proper motions are given with an accuracy of ~8 masyr-1. Corrections to the local-background-stars propermotions have been calculated, and absolute proper motions in theextragalactic frame are given. Whenever available, we also give opticalBT and VT magnitudes (from Tycho-2, ASCC-2.5),photographic BJ, RF, and IN magnitudes(from USNO-B1 catalog), and infrared J, H, and Ks magnitudes(from 2MASS). We also provide an estimated V magnitude and V-J color fornearly all catalog entries, useful for initial classification of thestars. The catalog is estimated to be over 99% complete at high Galacticlatitudes (|b|>15deg) and over 90% complete at lowGalactic latitudes (|b|>15deg), down to a magnitudeV=19.0, and has a limiting magnitude V=21.0. All the northern starslisted in the LHS and NLTT catalogs have been reidentified, and theirpositions, proper motions, and magnitudes reevaluated. The catalog alsolists a large number of completely new objects, which promise to expandvery significantly the census of red dwarfs, subdwarfs, and white dwarfsin the vicinity of the Sun.Based on data mining of the Digitized Sky Surveys (DSSs), developed andoperated by the Catalogs and Surveys Branch of the Space TelescopeScience Institute (STScI), Baltimore.Developed with support from the National Science Foundation (NSF), aspart of the NASA/NSF NStars program.
| Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
We complete construction of a catalog containing improved astrometry andnew optical/infrared photometry for the vast majority of NLTT starslying in the overlap of regions covered by POSS I and by the secondincremental Two Micron All Sky Survey (2MASS) release, approximately 44%of the sky. The epoch 2000 positions are typically accurate to 130 mas,the proper motions to 5.5 mas yr-1, and the V-J colors to0.25 mag. Relative proper motions of binary components are measured to 3mas yr-1. The false-identification rate is ~1% for11<~V<~18 and substantially less at brighter magnitudes. Theseimprovements permit the construction of a reduced proper-motion diagramthat, for the first time, allows one to classify NLTT stars intomain-sequence (MS) stars, subdwarfs (SDs), and white dwarfs (WDs). We inturn use this diagram to analyze the properties of both our catalog andthe NLTT catalog on which it is based. In sharp contrast to popularbelief, we find that NLTT incompleteness in the plane is almostcompletely concentrated in MS stars, and that SDs and WDs are detectedalmost uniformly over the sky δ>-33deg. Our catalogwill therefore provide a powerful tool to probe these populationsstatistically, as well as to reliably identify individual SDs and WDs.
| Photometric parallaxes for selected stars of color class M from the NLTT Catalog. IV - The declination zone +45 to +90 deg
VRI photometry and photometric parallaxes are presented for a sample of524 stars of color class m in the NLTT Catalog Luyten (1979) for whichno trigonometric parallaxes have been measured. Additional photometry of106 stars with trigonometric parallaxes is also presented. For theprogram stars, 67 have photometric parallaxes of not less than 0.04arcsec.
|
새 글 등록
관련 링크
새 링크 등록
다음 그룹에 속해있음:
|
관측 및 측정 데이터
천체목록:
|
