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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
| Photometry of Mercury from SOHO/LASCO and Earth. The Phase Function from 2 to 170 deg.
CCD observations of Mercury were obtained with the large anglespectrometric coronograph (LASCO) on the solar and heliosphericobservatory spacecraft, near superior and inferior solar conjunctions.Whole disk photometry was extracted from the orange and blue filterimages and transformed to V magnitudes on the UBV system. The LASCO datawere combined with ground-based, V-filter photometry acquired at largerelongation angles. The resulting photometric phase function covers thegreatest span of angles to date and is the first wide-range function tobe obtained since the era of visual observation. We analyzed the datausing a polynomial fit and a Hapke function fit, and derived thefollowing photometric results. Mercury's fully lit brightness, adjustedto a distance of 1.0 AU from the Sun and observer, was found to beV=-0.694(+/-0.030), which is more luminous than previously measured. Thecorresponding geometric albedo is 0.142(+/-0.005). The phase integral is0.478(+/-0.005) and resulting spherical albedo is 0.068(+/-0.003). Theupper limit of a possible rotational brightness variation is about 0.05magnitude. Mercury's brightness surges by more than 40% between phaseangles 10 and 2°, while the illuminated fraction of the diskincreases by less than 1%. A set of coefficients for Hapke's functionthat fit most of the phase curve includes h=0.065+/-0.002 indicatingthat Mercury and the Moon have similar regolith compaction states andparticle size distributions, and θ-bar=16°+/-1° implyinga macroscopically smoother surface than the Moon. However, we foundother solutions that fit the observations nearly as well withsignificantly smaller and larger values of h, and with values ofθ-bar around 25°. The wide range for θ-bar is due tothe inability of the model to fit the photometry obtained at large phaseangles. .
| Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable 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/qcar?J/A+A/367/521
| Research Note Hipparcos photometry: The least variable stars
The data known as the Hipparcos Photometry obtained with the Hipparcossatellite have been investigated to find those stars which are leastvariable. Such stars are excellent candidates to serve as standards forphotometric systems. Their spectral types suggest in which parts of theHR diagrams stars are most constant. In some cases these values stronglyindicate that previous ground based studies claiming photometricvariability are incorrect or that the level of stellar activity haschanged. Table 2 is 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/367/297
| K-Band Calibration of the Red Clump Luminosity
The average near-infrared (K-band) luminosity of 238 Hipparcos red clumpgiants is derived and then used to measure the distance to the Galacticcenter. These Hipparcos red clump giants have been previously employedas I-band standard candles. The advantage of the K-band is a decreasedsensitivity to reddening and perhaps a reduced systematic dependence onmetallicity. In order to investigate the latter, and also to refer ourcalibration to a known metallicity zero point, we restrict our sample ofred clump calibrators to those with abundances derived fromhigh-resolution spectroscopic data. The mean metallicity of the sampleis [Fe/H]=-0.18 dex (σ=0.17 dex). The data are consistent with nocorrelation between MK and [Fe/H] and only weakly constrainthe slope of this relation. The luminosity function of the sample peaksat MK=-1.61+/-0.03 mag. Next, we assemble published opticaland near-infrared photometry for ~20 red clump giants in a Baade'swindow field with a mean metallicity of [Fe/H]=-0.17+/-0.09 dex, whichis nearly identical to that of the Hipparcos red clump. Assuming thatthe average (V-I)0 and (V-K)0 colors of these twored clumps are the same, the extinctions in the Baade's window field arefound to be AV=1.56, AI=0.87, andAK=0.15, in agreement with previous estimates. We derive thedistance to the Galactic center: (m-M)0=14.58+/-0.11 mag, orR=8.24+/-0.42 kpc. The uncertainty in this distance measurement isdominated by the small number of Baade's window red clump giantsexamined here.
| Catalogs of temperatures and [Fe/H] averages for evolved G and K stars
A catalog of mean values of [Fe/H] for evolved G and K stars isdescribed. The zero point for the catalog entries has been establishedby using differential analyses. Literature sources for those entries areincluded in the catalog. The mean values are given with rms errors andnumbers of degrees of freedom, and a simple example of the use of thesestatistical data is given. For a number of the stars with entries in thecatalog, temperatures have been determined. A separate catalogcontaining those data is briefly described. Catalog only available atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Probing the {Na} BT I D and {K} BT I lambda 7699 resonance lines sensitivity to background opacity in late-type stars
We have measured the equivalent width WK of the K i resonanceline at 7699 Angstroms for a large sample of low activity late-typestars observed with high spectral resolution and we have verified thatthe relation WK vs. Teff is monotonicallydecreasing, for both dwarf and giant stars. This behaviour is differentfrom that of the Na I D lines for stars of the same type, which showedthat the relation WNa vs. Teff has a maximum forTeff ~ 4000 K, which is better defined for giants than fordwarfs (Tripicchio et al. 1997). The fit of the observed K I equivalentwidths by means of a NLTE spectral line synthesis using conventionalbackground opacity shows that, for dwarf stars, the adopted modelsoverestimate the observed WK for temperatures <~ 4000 K.This result is similar to that discussed for the Na I D lines in ourprevious paper. On the other hand, for giant stars with Teff<~ 3800 K these models in general underestimate WK. Thediscrepancies between observed and computed WK andWNa for cool stars are much stronger than the variations dueto uncertainties in either atmospheric model or line parameters, likeeffective temperature and surface gravity, or Van der Waals broadening.For M dwarf stars, the most convincing explanation for the disagreementis the lack of atomic and molecular line opacity in the adopted models.In fact, a NLTE spectral synthesis including an additional backgroundopacity reproduces with a good level of accuracy the equivalent widths,as well as the general shape of the profiles for both the Na I D and K Ilines, in a subsample of early-M dwarfs. Based on observations collectedat the European Southern Observatory (ESO), La Silla, Chile, and at theMcDonald Observatory, Mt. Locke, Texas, USA
| The ROSAT all-sky survey catalogue of optically bright late-type giants and supergiants
We present X-ray data for all late-type (A, F, G, K, M) giants andsupergiants (luminosity classes I to III-IV) listed in the Bright StarCatalogue that have been detected in the ROSAT all-sky survey.Altogether, our catalogue contains 450 entries of X-ray emitting evolvedlate-type stars, which corresponds to an average detection rate of about11.7 percent. The selection of the sample stars, the data analysis, thecriteria for an accepted match between star and X-ray source, and thedetermination of X-ray fluxes are described. Catalogue only available atCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Towards a fundamental calibration of stellar parameters of A, F, G, K dwarfs and giants
I report on the implementation of the empirical surface brightnesstechnique using the near-infrared Johnson broadband { (V-K)} colour assuitable sampling observable aimed at providing accurate effectivetemperatures of 537 dwarfs and giants of A-F-G-K spectral-type selectedfor a flux calibration of the Infrared Space Observatory (ISO). Thesurface brightness-colour correlation is carefully calibrated using aset of high-precision angular diameters measured by moderninterferometry techniques. The stellar sizes predicted by thiscorrelation are then combined with the bolometric flux measurementsavailable for a subset of 327 ISO standard stars in order to determineone-dimensional { (T, V-K)} temperature scales of dwarfs and giants. Theresulting very tight relationships show an intrinsic scatter induced byobservational photometry and bolometric flux measurements well below thetarget accuracy of +/- 1 % required for temperature determinations ofthe ISO standards. Major improvements related to the actual directcalibration are the high-precision broadband { K} magnitudes obtainedfor this purpose and the use of Hipparcos parallaxes for dereddeningphotometric data. The temperature scale of F-G-K dwarfs shows thesmallest random errors closely consistent with those affecting theobservational photometry alone, indicating a negligible contributionfrom the component due to the bolometric flux measurements despite thewide range in metallicity for these stars. A more detailed analysisusing a subset of selected dwarfs with large metallicity gradientsstrongly supports the actual bolometric fluxes as being practicallyunaffected by the metallicity of field stars, in contrast with recentresults claiming somewhat significant effects. The temperature scale ofF-G-K giants is affected by random errors much larger than those ofdwarfs, indicating that most of the relevant component of the scattercomes from the bolometric flux measurements. Since the giants have smallmetallicities, only gravity effects become likely responsible for theincreased level of scatter. The empirical stellar temperatures withsmall model-dependent corrections are compared with the semiempiricaldata by the Infrared Flux Method (IRFM) using the large sample of 327comparison stars. One major achievement is that all empirical andsemiempirical temperature estimates of F-G-K giants and dwarfs are foundto be closely consistent between each other to within +/- 1 %. However,there is also evidence for somewhat significant differential effects.These include an average systematic shift of (2.33 +/- 0.13) % affectingthe A-type stars, the semiempirical estimates being too low by thisamount, and an additional component of scatter as significant as +/- 1 %affecting all the comparison stars. The systematic effect confirms theresults from other investigations and indicates that previousdiscrepancies in applying the IRFM to A-type stars are not yet removedby using new LTE line-blanketed model atmospheres along with the updatedabsolute flux calibration, whereas the additional random component isfound to disappear in a broadband version of the IRFM using an infraredreference flux derived from wide rather than narrow band photometricdata. Table 1 and 2 are only available in the electronic form of thispaper
| The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
| A catalogue of [Fe/H] determinations: 1996 edition
A fifth Edition of the Catalogue of [Fe/H] determinations is presentedherewith. It contains 5946 determinations for 3247 stars, including 751stars in 84 associations, clusters or galaxies. The literature iscomplete up to December 1995. The 700 bibliographical referencescorrespond to [Fe/H] determinations obtained from high resolutionspectroscopic observations and detailed analyses, most of them carriedout with the help of model-atmospheres. The Catalogue is made up ofthree formatted files: File 1: field stars, File 2: stars in galacticassociations and clusters, and stars in SMC, LMC, M33, File 3: numberedlist of bibliographical references The three files are only available inelectronic form at the Centre de Donnees Stellaires in Strasbourg, viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5), or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The NaI resonance lines as a spectroscopic test of late-type stellar atmospheres.
We have tested current models for the atmospheres (including photosphereand low chromosphere) of late-type stars using the D resonance lines ofneutral sodium as a diagnostic. To this end, we have measured theequivalent widths of the D lines for a sample of 39 dwarf and 45 giantlate-type stars observed with high spectral resolution. We constructedphotospheric models over a grid in effective temperature and surfacegravity spanning the spectral types F to M, and luminosity classes V andIII of the sample stars. The model photospheres were extended into thechromosphere by assuming a suitable scaling from the Sun, andtheoretical Nai D equivalent widths were computed over the grid ofmodels including the deviations from local thermodynamic equilibrium. Bytaking into account both the experimental errors and the possiblevariations of stellar parameters (effective temperature, surfacegravity, sodium abundance and microturbulence), the comparison betweenobserved and computed equivalent widths allows us to state that themodel atmospheres we have used can reproduce the observations for thetwo luminosity classes and for all the spectral types except for theM-type stars. We have discussed the importance of line blanketing in thespectral analysis of these stars, but at present we cannot conclude thatthis effect would reduce the discrepancy.
| The Pulkovo Spectrophotometric Catalog of Bright Stars in the Range from 320 TO 1080 NM
A spectrophotometric catalog is presented, combining results of numerousobservations made by Pulkovo astronomers at different observing sites.The catalog consists of three parts: the first contains the data for 602stars in the spectral range of 320--735 nm with a resolution of 5 nm,the second one contains 285 stars in the spectral range of 500--1080 nmwith a resolution of 10 nm and the third one contains 278 stars combinedfrom the preceding catalogs in the spectral range of 320--1080 nm with aresolution of 10 nm. The data are presented in absolute energy unitsW/m(2) m, with a step of 2.5 nm and with an accuracy not lower than1.5--2.0%.
| ROSAT X-ray observations of a complete, volume-limited sample of late-type giants.
We have investigated a complete sample of the nearest 39 late typegiants (d<=25pc) for which we have probed the X-ray luminosityfunction with unprecedented sensitivity by deep (3...18ksec) ROSATPSPC-observations in the pointed mode, together with ROSAT All-Skysurvey (RASS) data. We confirm the X-ray dividing line for luminosityclass III giants as proposed by Haisch et al. (1991, 1992) and we findevidence, that essentially all luminosity class III giants withB-V<1.2 or spectral type
| 10-μm imaging of omega Centauri: the Mira variable V42 as the counterpart of the IRAS source?
For the first time, we have performed 10-μm high spatial resolutionimaging of Galactic globular clusters (GGCs) with ESO-TIMMI, and haveobtained a firm detection in a 35x35 arcsec^2 field of omega Centauri,about 70 arcsec south and 10 arcsec east of the cluster centre. Thedetected object is in good positional coincidence with the IRAS pointsource 13237-4713 and with the Mira variable V42. The most plausibleexplanation for the detected emission is the presence of a circumstellarenvelope around the red giant as a consequence of a currently occurringmass-loss event. This dusty structure, the tracer of a warm dustcomponent, is not resolved within the instrumental point spreadfunction, in good agreement with an expected equilibrium radius of onlya few hundred stellar radii. In addition, the coincidence between theMira variable and the IRAS point source is interesting, because it seemsto be a rare event in a globular cluster and implies that most of themass-loss episode is actually occurring within a short time-scale, inagreement with the theory of mass loss driven by thermal pulsation evenin low-mass stars.
| 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.
| Radio continuum emission from stars: a catalogue update.
An updated version of my catalogue of radio stars is presented. Somestatistics and availability are discussed.
| Evolved GK stars near the sun. I - The old disk population
A sample of nearly two thousand GK giants with intermediate band, (R,I),DDO and Geneva photometry has been assembled. Astrometric data is alsoavailable for most of the stars. The some 800 members of the old diskpopulation in the sample yield accurate luminosities (from two sources),reddening values and chemical abundances from calibrations of thephotometric parameters. Less than one percent of the objects arepeculiar in the sense that the flux distribution is abnormal. Thepeculiarity is signaled by strong CH (and Ba II) and weak CH. The CH+stars are all spectroscopic binaries, probably with white dwarfcompanions, whereas the CH- stars are not. A broad absorption band,centered near 3500 A, is found in the CH+ stars whereas the CH- objectshave a broad emission feature in the same region. The intensity of theseabsorptions and emissions are independent of the intensity of abnormalspectral features. Ten percent of the old disk sample have a heavyelement abundance from one and a half to three times the solar value.The distribution of the heavy element abundances is nearly a normal onewith a peak near solar abundance and ranges three times to one sixthsolar. The distribution of the (U, V) velocities is independent of theheavy element abundance and does not appear to be random. Ten percent ofthe old disk stars show a CN anomaly, equally divided between CN strongand CN weak. Several stars of individual astrometric or astrophysicalimportance are isolated.
| Optical Polarization of 1000 Stars Within 50-PARSECS from the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..101..551L&db_key=AST
| A Polarimetric Investigation on Interstellar Dust Within 50-PARSECS from the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&A...274..203L&db_key=AST
| Spectroscopic investigation of cool giants and the authenticity of their reported microwave emission
Surface velocities and metal abundances for 19 red giant stars in thespectral range G5 to M3 are derived on the basis of AAT echellespectroscopy data. Attention is given to the question of whether thestars reported to emit radio bursts had different physical properties(rotation rate, macroturbulence, microturbulence, and metal abundance)from those without the radio bursts, which might explain why they wereradio emitters. The various velocities had values consistent with thosepreviously found for other similar stars. There was an observed increasein both macroturbulent and, less definitely, microturbulent velocitieswith lateness of spectral type at K3 and later. A weak correlationbetween surface velocities and 8.4-GHz radio surface fluxes was found.No connection between iron abundances and radio surface fluxes wasdetected. It is concluded that few, if any, of the cool giants are radioemitters.
| CA II H and K measurements made at Mount Wilson Observatory, 1966-1983
Summaries are presented of the photoelectric measurements of stellar CaII H and K line intensity made at Mount Wilson Observatory during theyears 1966-1983. These results are derived from 65,263 individualobservations of 1296 stars. For each star, for each observing season,the maximum, minimum, mean, and variation of the instrumental H and Kindex 'S' are given, as well as a measurement of the accuracy ofobservation. A total of 3110 seasonal summaries are reported. Factorswhich affect the ability to detect stellar activity variations andaccurately measure their amplitudes, such as the accuracy of the H and Kmeasurements and scattered light contamination, are discussed. Relationsare given which facilitate intercomparison of 'S' values with residualintensities derived from ordinary spectrophotometry, and for convertingmeasurements to absolute fluxes.
| JHKLM standard stars in the ESO system
A list of 199 standard stars suitable for the ESO standard photometricsystem at JHKLM is given. Faint stars (although brighter than K = 7.7)to be used on larger telescopes are included. This list is based on ananalysis of all infrared photometric observations carried out at LaSilla from 1979 until 1989 inclusive. The accuracy of the data (about0.02 mag. at J, H, K, L, and M) is similar to the one achieved at SAAOand CTIO. Comparisons with these systems, as well as with the AAO andMSSO systems, are made: it is shown that the ESO system is very close tothe other ones, with the exception of CTIOs.
| High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances
A high-resolution spectroscopic survey of 671 G and K field giants isdescribed. Broad-band Johnson colors have been calibrated againstrecent, accurate effective temperature, T(eff), measurements for starsin the range 3900-6000 K. A table of polynomial coefficients for 10color-T(eff) relations is presented. Stellar atmosphere parameters,including T(eff), log g, Fe/H, and microturbulent velocity, are computedfor each star, using the high-resolution spectra and various publishedphotometric catalogs. For each star, elemental abundances for a varietyof species have been computed using a LTE spectrum synthesis program andthe adopted atmosphere parameters.
| MG II observed in the local interstellar medium - The local cloud
Observations of interstellar absorptions superposed on the chromosphericMg II emissions of nearby cool stars have been used to explore thestructure of the local interstellar medium along many lines of sight.The interstellar cloud in which the sun is immersed (the 'local cloud',hereafter LC) has not previously been detected using this technique.These Mg II data, taken from observations and from the VILSPA data bankof IUE, have been supplemented with other data taken from theliterature. The simultaneous analysis of the observed column densitiesand the radial velocity components of the absorbers is revealed as auseful diagnostic method in delineating the properties of the LC. Thepervasive presence of low densities toward the north Galactic pole andthe Galactic anticenter is confirmed, and lower limits to the Mg IIcolumn density than hitherto observed are presented. The LC is moving,in the LSR reference frame, toward (l, b) = (126 deg + 6 deg), away fromthe Sco-Cen-Oph association. It may extend to heliocentric distances ofup to 8 pc toward l of about 90 deg; in other directions its edge is atmost, at 2 pc from the sun.
| Chromospheric activity in evolved stars - The rotation-activity connection and the binary-single dichotomy
A tabulation of measured values of the Ca II H and K (S) index aretransformed to the original Mount Wilson definition of the index. Thetabulation includes main-sequence, evolved, single, and tidally coupled(RS CVn) binary stars. The (S) indices are analyzed against Wilson's(1976) I(HK) intensity estimates, showing that Wilson's estimates areonly a two-state indicator. Ca II H and K fluxes are computed andcalibrated with published values of rotation periods. It is found thatthe single and binary stars are consistent with a single relationshipbetween rotation and Ca II excess emission flux.
| A microwave survey of southern red giants
The Parkes 64-m telescope has been used to survey a complete sample ofnearby red giants. The sample consisted of all 82 stars within 30 pc inthe Bright Star Catalogue having spectral types G, K, M and luminosityclasses I, II, III and occurring south of the celestial equator.Twenty-four stars, consisting of 19 G or K giants, two G or K brightgiants (luminosity class II) and three of the five M-type giants weredetected in the sample. The emitted 8.4-GHz power and surface fluxdistributions of the 24 detections have medians two orders of magnitudelower than those of the active radio emitters in close binaries andother rapidly rotating single stars. It is shown that the field redgiants with their low rotation velocities probably fit into thesurface-flux/rotation-velocity relation derived for the faster rotators.
| A list of MK standard stars
Not Available
| The Perkins catalog of revised MK types for the cooler stars
A catalog is presented listing the spectral types of the G, K, M, and Sstars that have been classified at the Perkins Observatory in therevised MK system. Extensive comparisons have been made to ensureconsistency between the MK spectral types of stars in the Northern andSouthern Hemispheres. Different classification spectrograms have beengradually improved in spite of some inherent limitations. In thecatalog, the full subclasses used are the following: G0, G5, G8, K0, K1,K2, K3, K4, K5, M0, M1, M2, M3, M4, M5, M6, M7, and M8. Theirregularities are the price paid for keeping the general scheme of theoriginal Henry Draper classification.
| Stellar integrated fluxes in the wavelength range 380 NM - 900 NM derived from Johnson 13-colour photometry
Petford et al. (1988) have reported measured integrated fluxes for 216stars with a wide spread of spectral type and luminosity, and mentionedthat a cubic-spline integration over the relevant Johnson 13-colormagnitudes, converted to fluxes using Johnson's calibration, is inexcellent agreement with those measurements. In this paper a list of thefluxes derived in this way, corrected for a small dependence on B-V, isgiven for all the 1215 stars in Johnson's 1975 catalog with completeentries.
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Pozíciós és asztrometriai adatok
| Csillagkép: | Nyilas |
| Rektaszcenzió: | 19h04m41.00s |
| Deklináció: | -21°44'30.0" |
| Vizuális fényesség: | 3.77 |
| Távolság: | 42.571 parszek |
| RA sajátmozgás: | 76.5 |
| Dec sajátmozgás: | -57.4 |
| B-T magnitude: | 5.055 |
| V-T magnitude: | 3.861 |
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