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CHARM2: An updated Catalog of High Angular Resolution Measurements
We present an update of the Catalog of High Angular ResolutionMeasurements (CHARM, Richichi & Percheron \cite{CHARM}, A&A,386, 492), which includes results available until July 2004. CHARM2 is acompilation of direct measurements by high angular resolution methods,as well as indirect estimates of stellar diameters. Its main goal is toprovide a reference list of sources which can be used for calibrationand verification observations with long-baseline optical and near-IRinterferometers. Single and binary stars are included, as are complexobjects from circumstellar shells to extragalactic sources. The presentupdate provides an increase of almost a factor of two over the previousedition. Additionally, it includes several corrections and improvements,as well as a cross-check with the valuable public release observationsof the ESO Very Large Telescope Interferometer (VLTI). A total of 8231entries for 3238 unique sources are now present in CHARM2. Thisrepresents an increase of a factor of 3.4 and 2.0, respectively, overthe contents of the previous version of CHARM.The catalog is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/431/773
| J - K DENIS photometry of a VLTI-selected sample of bright southern stars
We present a photometric survey of bright southern stars carried outusing the DENIS instrument equipped with attenuating filters. Theobservations were carried out not using the survey mode of DENIS, butwith individual target pointings. This project was stimulated by theneed to obtain near-infrared photometry of stars to be used in earlycommissioning observations of the ESO Very Large TelescopeInterferometer, and in particular to establish a network of brightcalibrator sources.We stress that near-infrared photometry is peculiarly lacking for manybright stars. These stars are saturated in 2MASS as well as in regularDENIS observations. The only other observations available for brightinfrared stars are those of the Two Micron Sky Survey dating from overthirty years ago. These were restricted to declinations above≈-30°, and thus cover only about half of the sky accessible fromthe VLTI site.We note that the final 2MASS data release includes photometry of brightstars, obtained by means of point-spread function fitting. However, thismethod only achieves about 30% accuracy, which is not sufficient formost applications.In this work, we present photometry for over 600 stars, each with atleast one and up to eight measurements, in the J and K filters. Typicalaccuracy is at the level of 0\fm05 and 0\fm04 in the J and K_s bands,respectively.Based on observations collected at the European Southern Observatory, LaSilla.Tables 1 and 2 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/413/1037
| CHARM: A Catalog of High Angular Resolution Measurements
The Catalog of High Angular Resolution Measurements (CHARM) includesmost of the measurements obtained by the techniques of lunaroccultations and long-baseline interferometry at visual and infraredwavelengths, which have appeared in the literature or have otherwisebeen made public until mid-2001. A total of 2432 measurements of 1625sources are included, along with extensive auxiliary information. Inparticular, visual and infrared photometry is included for almost allthe sources. This has been partly extracted from currently availablecatalogs, and partly obtained specifically for CHARM. The main aim is toprovide a compilation of sources which could be used as calibrators orfor science verification purposes by the new generation of largeground-based facilities such as the ESO Very Large Interferometer andthe Keck Interferometer. The Catalog is available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/386/492, and from theauthors on CD-Rom.
| New binary stars discovered by lunar occultations. VI.
We present additional results from our ongoing lunar occultationprogram. Observations are presented here for a total of seventeensources, for the majority of which one or two new companions aredetected. The sample comprises mostly field stars, spanning a largerange of spectral types. Two infrared objects without opticalcounterpart are also included. The range of projected separations is0farcs007 to 0farcs162 . We report on the following binary stars:IRAS 16576-2116, IRAS 19495-1628,IRAS 18033-1955, CGCS 3964,SAO 94064, EI Tau, SAO93950, SAO 79217, SAO79285 and SAO 80075. We found HD247924 and SAO 139322 to be triple systems.In the case of SAO 93950, the revised analysis of twooccultation events has provided the true position angle and separationof this system. We also observed the young T Tauri star GG TauA, where we detected a significant orbital motion with respectto the latest available measurements. In two cases, SAO79285 and SAO 139322, a companion wasalready claimed on the basis of Hipparcos results, but our observationsare not entirely consistent with these latter. Finally, our sampleincludes four stars known to be binary, namely SAO186497, SAO 162183, SAO96753 and SAO 161192, for which we did notdetect a companion. Among these, our negative detection of the companionof SAO 162183 poses strong constraints on theparameters of this presumed binary. Based on observations collected atTIRGO (Gornergrat, Switzerland), and at Calar Alto (Spain). TIRGO isoperated by CNR-CAISMI Arcetri, Italy. Calar Alto is operated by theGerman-Spanish Astronomical Center.
| Lunar occultation summary. III
Observations of 242 photoelectric lunar occultation events studied atErwin W. Fick Observatory are reported. Approximately one-fourth ofthese are reappearances. From each observation are estimated the minimummagnitude differences between the observed object and possibleundetected companions. Occultation observations are given of 23 starsbrighter than 6th mag, including Alpha Vir, Beta-1 Sco, Mu Gem, Xi-2Sgr, Zeta Tau, Lambda Gem, and Beta Cap.
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Observation and Astrometry data
| Constellation: | Δίδυμοι |
| Right ascension: | 07h18m37.37s |
| Declination: | +16°35'10.5" |
| Apparent magnitude: | 8.489 |
| Distance: | 209.644 parsecs |
| Proper motion RA: | 6.8 |
| Proper motion Dec: | -15.9 |
| B-T magnitude: | 10.238 |
| V-T magnitude: | 8.634 |
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