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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
| Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters
The availability of the Hipparcos Catalogue has triggered many kinematicand dynamical studies of the solar neighbourhood. Nevertheless, thosestudies generally lacked the third component of the space velocities,i.e., the radial velocities. This work presents the kinematic analysisof 5952 K and 739 M giants in the solar neighbourhood which includes forthe first time radial velocity data from a large survey performed withthe CORAVEL spectrovelocimeter. It also uses proper motions from theTycho-2 catalogue, which are expected to be more accurate than theHipparcos ones. An important by-product of this study is the observedfraction of only 5.7% of spectroscopic binaries among M giants ascompared to 13.7% for K giants. After excluding the binaries for whichno center-of-mass velocity could be estimated, 5311 K and 719 M giantsremain in the final sample. The UV-plane constructed from these datafor the stars with precise parallaxes (σπ/π≤20%) reveals a rich small-scale structure, with several clumpscorresponding to the Hercules stream, the Sirius moving group, and theHyades and Pleiades superclusters. A maximum-likelihood method, based ona Bayesian approach, has been applied to the data, in order to make fulluse of all the available stars (not only those with precise parallaxes)and to derive the kinematic properties of these subgroups. Isochrones inthe Hertzsprung-Russell diagram reveal a very wide range of ages forstars belonging to these groups. These groups are most probably relatedto the dynamical perturbation by transient spiral waves (as recentlymodelled by De Simone et al. \cite{Simone2004}) rather than to clusterremnants. A possible explanation for the presence of younggroup/clusters in the same area of the UV-plane is that they have beenput there by the spiral wave associated with their formation, while thekinematics of the older stars of our sample has also been disturbed bythe same wave. The emerging picture is thus one of dynamical streamspervading the solar neighbourhood and travelling in the Galaxy withsimilar space velocities. The term dynamical stream is more appropriatethan the traditional term supercluster since it involves stars ofdifferent ages, not born at the same place nor at the same time. Theposition of those streams in the UV-plane is responsible for the vertexdeviation of 16.2o ± 5.6o for the wholesample. Our study suggests that the vertex deviation for youngerpopulations could have the same dynamical origin. The underlyingvelocity ellipsoid, extracted by the maximum-likelihood method afterremoval of the streams, is not centered on the value commonly acceptedfor the radial antisolar motion: it is centered on < U > =-2.78±1.07 km s-1. However, the full data set(including the various streams) does yield the usual value for theradial solar motion, when properly accounting for the biases inherent tothis kind of analysis (namely, < U > = -10.25±0.15 kms-1). This discrepancy clearly raises the essential questionof how to derive the solar motion in the presence of dynamicalperturbations altering the kinematics of the solar neighbourhood: doesthere exist in the solar neighbourhood a subset of stars having no netradial motion which can be used as a reference against which to measurethe solar motion?Based on observations performed at the Swiss 1m-telescope at OHP,France, and on data from the ESA Hipparcos astrometry satellite.Full Table \ref{taba1} is only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/430/165}
| Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/397/997
| A catalogue of calibrator stars for long baseline stellar interferometry
Long baseline stellar interferometry shares with other techniques theneed for calibrator stars in order to correct for instrumental andatmospheric effects. We present a catalogue of 374 stars carefullyselected to be used for that purpose in the near infrared. Owing toseveral convergent criteria with the work of Cohen et al.(\cite{cohen99}), this catalogue is in essence a subset of theirself-consistent all-sky network of spectro-photometric calibrator stars.For every star, we provide the angular limb-darkened diameter, uniformdisc angular diameters in the J, H and K bands, the Johnson photometryand other useful parameters. Most stars are type III giants withspectral types K or M0, magnitudes V=3-7 and K=0-3. Their angularlimb-darkened diameters range from 1 to 3 mas with a median uncertaintyas low as 1.2%. The median distance from a given point on the sky to theclosest reference is 5.2degr , whereas this distance never exceeds16.4degr for any celestial location. The catalogue is only available inelectronic form at the 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/393/183
| 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.
| Spectral Irradiance Calibration in the Infrared. X. A Self-Consistent Radiometric All-Sky Network of Absolutely Calibrated Stellar Spectra
We start from our six absolutely calibrated continuous stellar spectrafrom 1.2 to 35 μm for K0, K1.5, K3, K5, and M0 giants. These wereconstructed as far as possible from actual observed spectral fragmentstaken from the ground, the Kuiper Airborne Observatory, and the IRAS LowResolution Spectrometer, and all have a common calibration pedigree.From these we spawn 422 calibrated ``spectral templates'' for stars withspectral types in the ranges G9.5-K3.5 III and K4.5-M0.5 III. Wenormalize each template by photometry for the individual stars usingpublished and/or newly secured near- and mid-infrared photometryobtained through fully characterized, absolutely calibrated,combinations of filter passband, detector radiance response, and meanterrestrial atmospheric transmission. These templates continue ourongoing effort to provide an all-sky network of absolutely calibrated,spectrally continuous, stellar standards for general infrared usage, allwith a common, traceable calibration heritage. The wavelength coverageis ideal for calibration of many existing and proposed ground-based,airborne, and satellite sensors, particularly low- tomoderate-resolution spectrometers. We analyze the statistics of probableuncertainties, in the normalization of these templates to actualphotometry, that quantify the confidence with which we can assert thatthese templates truly represent the individual stars. Each calibratedtemplate provides an angular diameter for that star. These radiometricangular diameters compare very favorably with those directly observedacross the range from 1.6 to 21 mas.
| 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.
| Circumstellar envelopes and Asymptotic Giant Branch stars
Red giants are sometimes surrounded by envelopes, the result of theejection of stellar matter at a large rate (˙ M>10-7Msolar/yr) and at a low velocity (10 km/s). Inthis review the envelopes are discussed and the relation between starsand envelope: what stars combine with what envelopes? The envelope emitsradiation by various processes and has been detected at all wavelengthsbetween the visual and the microwave range. I review the observations ofcontinuum radiation emitted by dust particles and of rotationaltransitions of molecules, where these molecules have been excited bythermal or by non-thermal (``maser'') processes. I discuss mainly theoxygen-rich stars, those of spectral type M, and only briefly theclosely related carbon-rich stars. By and large the density in theenvelope is well described by spherically symmetric outflow at aconstant velocity; on the time scale needed to flow from stellar surfaceto the outermost layers, i.e. 105 yr, the loss of mass issometimes interrupted suddenly after which the envelope becomes``detached'' from the star. The temperature decreases when movingoutward; heat input is by friction between dust particles and gas andcooling occurs by line radiation by various molecules, especially byH2O. The molecular composition is determined by formation inan equilibrium process deep in the atmosphere and by destruction in theouter parts of the outflow by interstellar UV radiation (H2,CO, H2O) or by depletion due to condensation on dust grains(SiO); dust particles of silicate material solidify where the radiationtemperature is decreased to about 1000 K, and this is at a few stellarradii. The various continuum spectra produced by the dust particles indifferent stars are well modelled by a simple model of the density anddust temperature distribution plus the assumption that the particlesconsist of ``dirty silicate'', i.e. silicate with Fe and Al ions added.A large range of optical depths, τ 9.7μ m , isobserved: from 0.01 to 10. In envelopes with large optical depth thestar itself can no longer be detected directly. Model calculations alsoshow that the momentum in the outflow, i.e. ˙ Mv out isprovided by radiation pressure on the dust particles followed by thecomplete transfer of this momentum to the gas. The mass-loss rateitself, ˙ M , is not determined by radiation pressure but by dynamicprocesses in the region below the dust condensation layer. Whenτ9.7 μ m is sufficiently large its measurement, thatof the stellar luminosity, L* and that of the outflowvelocity, vout, permit the determination of ˙ M , i.e.the total outflow rate, without making assumptions about the abundanceof the dust particles or of the molecular gases. Detached envelopes havebeen seen in a few cases. Thermal molecular radiation is faint comparedto the maser emission but has been measured in distant stars, e.g. instars near the galactic center. Different molecules outline different``spheres'' around the star. The largest sphere (a radius of 0.1 pc) isoutlined by an emission line belonging to the CO(v=0, J=1-> 0)transition. Higher rotational transitions of CO give smaller diameters.A comparison of CO (J=2-> 1) and (J=1-> 0) fluxes in stars withvery thick envelopes leads to the conclusion that an abrupt decrease inthe mass-loss rate occurred some ten thousand years ago. Three moleculesproduce each several maser lines: SiO, H2O and OH. Severalnew H2O lines have recently been discovered; theirexploration has hardly been started. The high intensity of the maserlines makes interferometry possible and hence detailed mapping. The SiOlines are formed deep in the envelope, below the dust condensationlayer. OH maser lines are produced farthest out, H2O lines inbetween. The excitation mechanisms for most maser lines is understoodglobally, but detailed models are lacking, largely because the problemis non-linear and the solution of the radiative transfer equationrequires a highly anisotropic geometry. The geometrical and kinematicalproperties of the 1612 MHz OH maser, which in many objects is verystrong, are explained by a thin shell of OH; because the angulardiameter of the shell can be measured directly and the linear diametercan be determined from the difference in the time of maximum flux ofblue and red maser peaks, the distance of the shell and of the star canbe measured. The presence or absence of individual maser lines appearsto depend on the value of τ {9.7μ m} and is welldescribed by a sequence called ``Lewis' chronology''. The central staris a long-period variable with a period of 300 days or longer and with alarge luminosity amplitude (Δ mbol >0.7m). Evidence is given that each star has the maximumluminosity it will reach during its evolution and that it is athermally-pulsing Asymptotic-Giant-Branch star (TP-AGB) with amain-sequence mass between 1 and 6 Msolar . Stars of the samemain-sequence mass, Mms, have different mass-loss rates, insome cases by a factor of 10. The mass-loss rate probably increases withtime, and the highest mass-loss rates are reached toward the end of theevolution. Stars with higher Mms ultimately reach highermass-loss rates. The calibration of the main-sequence mass is reviewed.Most Mira variables with mass loss have a mass between 1.0 and 1.2Msolar . OH/IR stars with periods over 1000 days have nocounterparts among the carbon stars and thus have Mms >4.5Msolar. Stars as discussed in this review have been foundonly in the thin galactic disk and in the bulge. Finally I reviewseveral recently proposed scenarios for TP-AGB evolution in which massloss is taken into account. These scenarios represent the observationsquite well; their major short-coming is the lack of an explanation whythe central stars are always large-amplitude, long-period variables andwhy such stars are the ones with high mass-loss rates.
| Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| New OH/IR stars from color-selected IRAS sources. II - an unbiased 1612 MHz survey
Results are reported from the Arecibo 1612-MHz survey of color-selectedIRAS sources. This paper examines 1294 sources, to detect 86, 79 of themnew detections, all with 25-micron fluxes greater than 2 Jy. The specialfeature of this work is its coverage of sources with high absolute valueof b(II), so the 1612-MHz characteristics of stars with small progenitormasses are determined. This provides direct observational evidence thatradiation pressure acting on dust grains influences mass loss from redgiants.
| A catalog of precise reference star positions for the astrometry network of the international comet P/Halley compaign
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1987A&AS...71..525D&db_key=AST
| 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.
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
| Radial Velocities of 360 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1952ApJ...115..157W&db_key=AST
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Pozíciós és asztrometriai adatok
| Csillagkép: | Halak |
| Rektaszcenzió: | 00h16m45.68s |
| Deklináció: | +10°14'41.2" |
| Vizuális fényesség: | 6.522 |
| Távolság: | 1052.632 parszek |
| RA sajátmozgás: | 2.7 |
| Dec sajátmozgás: | 8.4 |
| B-T magnitude: | 8.923 |
| V-T magnitude: | 6.721 |
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