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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
| 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.
| Angular diameter and effective temperature of a sample of 15M giants at 2.2μm from lunar occultation observations
High angular resolution measurements of a sample of 15M giants at2.2μm by the technique of lunar occultation are presented in thispaper. We obtain angular diameters for 11 sources of which five are thefirst diameter measurements. For these resolved sources we haveestimated the effective temperatures, which are consistent with previouscalibrations. For the other four sources we put the first upper limitson their angular sizes to be 2mas. Two sources, namely IRC+20090 andIRC+20067, yield appreciably low temperatures, which could point totheir possible Mira nature. For sources with Hipparcos parallaxmeasurements, we have calculated the linear radii.
| A homogeneous temperature calibration for K and M giants with an extension to the coolest stars
In this paper we present a new estimate of the effective temperatures of32 giant stars in the spectral range K0 to M10. The sample includes also4 Mira stars. The temperatures are based on a homogeneous set of angulardiameters obtained by our group by the technique of lunar occultations,and using a photometric and spectroscopic coverage with a combination oforiginal measurements and literature data. Most of this basic materialhad been presented in previous papers, but in the present work we deriveimproved effective temperatures by using for the first time a grid ofnumerical center-to-limb darkening models. We use this revision toderive a new calibration of the effective temperature of K and M giantstars, which has the advantage of being based on only one, highlyhomogeneous set of data (while previous calibrations often used mixeddata sets). The resulting calibration is extended to the coolest stars,reaching for the first time M9 for the non-Mira stars, and M10 for theMira stars. In this latter case the calibration does not account forpulsation phase variations and is only tentative. In the region ofoverlap with previously existing calibrations, we find a largelysatisfactory agreement, although some differences exist and arediscussed. In particular, it appears that the calibration of theeffective temperature of cool Mira stars requires additionalobservational as well as theoretical effort. Seven of the stars in oursample appear to exhibit an effective temperature that departssignificantly from the mean relation (~ 900 K cooler between K1 and M8),and no simple explanation in terms of possible bias or experimentalerror could be found. Based on observations collected at TIRGO(Gornergrat, Switzerland), at Calar Alto (Spain) and at the EuropeanSouthern Observatory in La Silla (Chile). TIRGO is operated by CNR --CAISMI Arcetri, Italy. Calar Alto is operated by the German-SpanishAstronomical Center.
| Infrared high angular resolution measurements of stellar sources. III. Angular diameters and effective temperatures of eleven late-type giants
Near-infrared lunar occultation observations of eleven late-type giantsin the spectral range K0 to M6 (including one carbon star) are reportedhere. These stars are resolved from our observations carried out at2.2mu m, resulting in accurate determinations of their angular sizes,with values in the range 1.4 to 7.1 milliseconds of arc (mas) and atypical accuracy of 0.12 mas. Nine out of eleven sources are resolvedfor the first time. In addition, near infrared photometric observationsof some of the sources have been carried out to compute stellarbolometric fluxes, and hence derive the effective temperatures. Ouraccurate angular diameter measurements (at least in the case of eightsources) have the potential to provide effective temperatures with anaccuracy less than 3% when bolometric fluxes become available with anaccuracy less than 10%. The observed sources are discussed inconjunction with earlier high angular resolution observations andavailable photometric data. A comparison of the current performance oflunar occultations and long baseline interferometry in the field ofangular diameters and effective temperatures is presented. Based onobservations collected at TIRGO (Gornergrat, Switzerland), at Calar Alto(Spain), and at the European Southern Observatory (La Silla, Chile).TIRGO is operated by CNR-CAISMI Arcetri, Italy. Calar Alto is operatedby the German-Spanish Astronomical Center.
| Classification and Identification of IRAS Sources with Low-Resolution Spectra
IRAS low-resolution spectra were extracted for 11,224 IRAS sources.These spectra were classified into astrophysical classes, based on thepresence of emission and absorption features and on the shape of thecontinuum. Counterparts of these IRAS sources in existing optical andinfrared catalogs are identified, and their optical spectral types arelisted if they are known. The correlations between thephotospheric/optical and circumstellar/infrared classification arediscussed.
| The TIRGO Lunar Occultation Program: Summary of the 1985-1995 Observations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996AJ....112.2786R&db_key=AST
| Lunar occultations of IRAS point sources, 1991-2000
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989ApJS...69..651C&db_key=AST
| Photoelectric photometry of M-type stars
UBVRI photoelectric photometry was obtained for 110 M-type starscontained in the Caltech Two-Micron Survey and the revised AFGL Catalog.Of the 110 stars, 58 have a color index (B-R) greater than or equal to 4mag. A graph is given of (V-R) versus (V-I) for the present stars.
| IRAS catalogues and atlases - Atlas of low-resolution spectra
Plots of all 5425 spectra in the IRAS catalogue of low-resolutionspectra are presented. The catalogue contains the average spectra ofmost IRAS poiont sources with 12 micron flux densities above 10 Jy.
| A low-detection limit search for OH emission from infrared stars
We have used the 300 m telescope of the Arecibo Observatory to examine154 cool luminous stars for 18 cm OH emission. Six of the stars (RU Ari,R Com, T Com, RX Oph, UU Peg, and RT Vir) were found to show OHemission. For the stars without OH emission, we have establisheddetection limits several times smaller than those of previous surveys.
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Observation and Astrometry data
| Constellation: | Κριός |
| Right ascension: | 02h56m52.16s |
| Declination: | +14°36'34.5" |
| Apparent magnitude: | 8.792 |
| Proper motion RA: | 45.4 |
| Proper motion Dec: | -4.8 |
| B-T magnitude: | 10.599 |
| V-T magnitude: | 8.942 |
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