Inici     Començant     Sobreviure a l'Univers    
Inhabited Sky
    News@Sky     Astro Fotografia     La Col·lecció     Fòrum     Blog New!     FAQ     Premsa     Login  

γ Cha (Xiǎodǒusān)


Contingut

Imatges

Carregar la teva Imatge

DSS Images   Other Images


Articles Relacionats

New insights on the complex planetary nebula Hen 2-113
We report on infrared observations of the planetary nebula Hen 2-113obtained with VLT/NACO, VLTI/MIDI, VLT/ISAAC and TIMMI at the ESO 3.6 m.Hen 2-113 exhibits a clear ring-like structure superimposed to a morediffuse environment visible in the L' (3.8 μm), M' (4.78 μm) and8.7 μm bands. No clear core at 8.7 μm and no fringes through the Nband could be detected for this object with MIDI. A qualitativeinterpretation of the object structure is proposed using a diabolo-likegeometrical model. The PAH content of the nebula was also studied withISAAC and TIMMI observations. This indicates that the PAHs are mostlyconcentrated towards the lobes of the diabolo and the bipolar lobes ofthe nebula. In L' band, a void 0.3 arcsec in diameter was discoveredwith NACO around the central source. The L' and M' fluxes from thecentral source were derived from NACO data indicating an importantinfrared excess with respect to the expected stellar emission based onstellar models and short wavelength data. The observed flux from thissource in the L' and M' is about 300 and 800 times respectively thanthose expected from a model including only the central star. Moreover,the central object appears resolved in L' band with measured FWHM of 155mas. This infrared excess can be explained by emission from a cocoon ofhot dust (T˜1000 K) with a total mass~10-9~Mȯ.

A radial velocity survey of low Galactic latitude structures - I. Kinematics of the Canis Major dwarf galaxy
As part of a radial velocity survey of low Galactic latitude structuresthat we undertook with the 2dF spectrograph on the Anglo-AustralianTelescope, we present the radial velocities of more than 1500 red giantbranch and red clump stars towards the centre of the Canis Major dwarfgalaxy. With a mean velocity of 72 +/- 7kms-1 at aheliocentric distance of 5.5kpc and 114 +/- 2kms-1 at 8.5kpc,these stars present a peculiar distance - radial velocity relation thatis unlike that expected from thin or thick disc stars. Moreover, theybelong to a kinematically cold population with an intrinsic dispersionthat may be as low as 11+3-1kms-1. Acomparison of the velocity distribution obtained in this work withprevious studies shows the importance of using our new reductionpipeline and averaging the velocities obtained from different templates.The radial velocity distribution is used to select Canis Major stars inthe UCAC2.0 proper motion catalogue and derive proper motions inGalactic coordinates of (μl, μb) = (-3.6 +/-0.8masyr-1, 1.5 +/- 0.4masyr-1) for the dwarfgalaxy, which after correcting for the reflex solar motion along thisline of sight gives (μ'l, μ'b) = (-6.8 +/-0.8masyr-1, 0.8 +/- 0.4masyr-1), corresponding toa prograde orbit with a tangential velocity of ~235kms-1 atthe average distance of ~7.2kpc. All these kinematic constraints can bereproduced in simulations of the accretion of a dwarf on to the Galacticdisc. Such a process could also be responsible for the Monoceros Ringthat has recently been shown to encompass the Galactic disc. However,without constraints on the kinematics of the tidal arms emerging fromthe Canis Major dwarf, it is not yet possible to definitively prove alink between the two structures.

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

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.

A multi-epoch spectrophotometric atlas of symbiotic stars
A multi-epoch, absolute-fluxed spectral atlas extending from about 3200to 9000 Å is presented for 130 symbiotic stars, including membersof the LMC, SMC and Draco dwarf galaxies. The fluxes are accurate tobetter than 5% as shown by comparison with Tycho and ground-basedphotometric data. The spectra of 40 reference objects (MKK cool giantstandards, Mira and Carbon stars, planetary nebulae, white dwarfs, hotsub-dwarfs, Wolf-Rayet stars, classical novae, VV Cep and Herbig Ae/Beobjects) are provided to assist the interpretation of symbiotic starspectra. Astrometric positions and counterparts in astrometriccatalogues are derived for all program symbiotic stars. The spectra areavailable in electronic form from the authors. Based on observationscollected with the telescopes of the European Southern Observatory (ESO,Chile) and of the Padova & Asiago Astronomical Observatories(Italy). Tables 2 and 3 are only available in electronic form (a) at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/383/188, and (b) from thepersonal home page http://ulisse.pd.astro.it/symbio_atlas/ Figures 4-256are only available in electronic form (a) at http://www.edpsciences.organd (b) from the personal home pagehttp://ulisse.pd.astro.it/symbio_atlas/

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

The proper motions of fundamental stars. I. 1535 stars from the Basic FK5
A direct combination of the positions given in the HIPPARCOS cataloguewith astrometric ground-based catalogues having epochs later than 1939allows us to obtain new proper motions for the 1535 stars of the BasicFK5. The results are presented as the catalogue Proper Motions ofFundamental Stars (PMFS), Part I. The median precision of the propermotions is 0.5 mas/year for mu alpha cos delta and 0.7mas/year for mu delta . The non-linear motions of thephotocentres of a few hundred astrometric binaries are separated intotheir linear and elliptic motions. Since the PMFS proper motions do notinclude the information given by the proper motions from othercatalogues (HIPPARCOS, FK5, FK6, etc.) this catalogue can be used as anindependent source of the proper motions of the fundamental stars.Catalogue (Table 3) is only available at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strastg.fr/cgi-bin/qcat?J/A+A/365/222

Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions
The FK6 is a suitable combination of the results of the HIPPARCOSastrometry satellite with ground-based data, measured over more than twocenturies and summarized in the FK5. Part I of the FK6 (abbreviatedFK6(I)) contains 878 basic fundamental stars with direct solutions. Suchdirect solutions are appropriate for single stars or for objects whichcan be treated like single stars. From the 878 stars in Part I, we haveselected 340 objects as "astrometrically excellent stars", since theirinstantaneous proper motions and mean (time-averaged) ones do not differsignificantly. Hence most of the astrometrically excellent stars arewell-behaving "single-star candidates" with good astrometric data. Thesestars are most suited for high-precision astrometry. On the other hand,199 of the stars in Part I are Δμ binaries in the sense ofWielen et al. (1999). Many of them are newly discovered probablebinaries with no other hitherto known indication of binarity. The FK6gives, besides the classical "single-star mode" solutions (SI mode),other solutions which take into account the fact that hidden astrometricbinaries among "apparently single-stars" introduce sizable "cosmicerrors" into the quasi-instantaneously measured HIPPARCOS proper motionsand positions. The FK6 gives in addition to the SI mode the "long-termprediction (LTP) mode" and the "short-term prediction (STP) mode". TheseLTP and STP modes are on average the most precise solutions forapparently single stars, depending on the epoch difference with respectto the HIPPARCOS epoch of about 1991. The typical mean error of anFK6(I) proper motion in the single-star mode is 0.35 mas/year. This isabout a factor of two better than the typical HIPPARCOS errors for thesestars of 0.67 mas/year. In the long-term prediction mode, in whichcosmic errors are taken into account, the FK6(I) proper motions have atypical mean error of 0.50 mas/year, which is by a factor of more than 4better than the corresponding error for the HIPPARCOS values of 2.21mas/year (cosmic errors included).

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.

Stellar radii of M giants
We determine the stellar radii of the M giant stars in the Hipparcoscatalogue that have a parallax measured to better than 20% accuracy.This is done with the help of a relation between a visual surfacebrightness parameter and the Cousins (V - I) colour index, which wecalibrate with M giants with published angular diameters.The radii of(non-Mira) M giants increase from a median value of 50 R_Sun at spectraltype M0 III to 170 R_Sun at M7/8 III. Typical intermediate giant radiiare 65 R_Sun for M1/M2, 90 R_Sun for M3, 100 R_Sun for M4, 120 R_Sun forM5 and 150 R_Sun for M6. There is a large intrinsic spread for a givenspectral type. This variance in stellar radius increases with latertypes but in relative terms, it remains constant.We determineluminosities and, from evolutionary tracks, stellar masses for oursample stars. The M giants in the solar neighbourhood have masses in therange 0.8-4 M_Sun. For a given spectral type, there is a close relationbetween stellar radius and stellar mass. We also find a linear relationbetween the mass and radius of non-variable M giants. With increasingamplitude of variability we have larger stellar radii for a given mass.

Obscured Asymptotic Giant Branch stars in the Magellanic Clouds. IV. Carbon stars and OH/IR stars
We present N-band photometry for a sample of 21 dust-enshrouded AGBstars in the Large Magellanic Cloud, and three additional sources in theSmall Magellanic Cloud. Together with near-infrared photometry, this isused to give a tentative classification into carbon and oxygen-richatmospheres. Bolometric luminosities are also estimated for these stars.In addition, we present the results of a survey for OH masers in theLMC, which resulted in the discovery of OH maser emission fromIRAS04407-7000. Spectra between 600 and 1000 nm have been obtained fortwo heavily obscured AGB stars in the LMC, confirming them to be highlyreddened very late M-type giants. Because the dust-enshrouded stars areclearly undergoing heavy mass loss they are assumed to be very near thetermination of their respective Asymptotic Giant Branch phases. Thefraction of mass-losing carbon stars decreases with increasingluminosity, as expected from Hot Bottom Burning. The best candidatecarbon star, with M_bol ~ -6.8 mag, is the most luminous mass-losingcarbon star in the Magellanic Clouds, and amongst the most luminous AGBstars. At lower luminosities (M_bol ~ -5 mag) both oxygen and carbonstars are found. This may be explained by a range in metallicity of theindividual mass-losing AGB stars. based on observations obtained at theEuropean Southern Observatory (La Silla, Chile: proposal ESO 54.E-0135),the South African Astronomical Observatory, and the Australia TelescopeNational Facility

A new method to solve stellar population synthesis problems with the use of a data base
In this paper, we present a new solution of the stellar populationsynthesis problem using as primary information the equivalent width ofthe absorption lines observed in the spectra of, say, a galaxy. It isshown that this problem leads to a formulation akin to the maximumentropy method so successfully applied in image analysis and elsewhere.Emphasis is placed on the fact that it is a certain type of inverseproblem for which many local solutions do exist. Among these localsolutions there generally exists a global solution which is difficult toobtain in practice. A new method to search for this solution isproposed. First we solve a problem that is slightly different from theoriginal one but which possesses a unique solution. Then we return tothe original problem using that solution as a starting point of a localexploration. Because the change between the two formulations getssmaller as the errors in the data get smaller, we have great confidencethat the solution we find in this way is an efficient one. As thissolution may not be physical, we argue that either (1) the errors in theobservations are too big for any method to work properly or (2) it isthe signature of an inadequate stellar base. We then explore allboundaries by removing one or more stars from the data base and retainonly those truncated data bases for which the solution is physical. Thefinal solution (called the GPG solution) is that solution whichminimizes a certain distance criterion. We have tested our methodagainst noise in the data by Monte Carlo simulations and found it to begenerally unbiased and to have a small dispersion around the true valuefor signal-to-noise ratio as low as 10. This property holds true at verylow signal-to-noise ratio for stellar contributions greater thanapproximately 10 per cent. An example of the new method for the study ofthe active galaxy NGC 5643 is given.

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.

A library of H band stellar spectra for stellar population analysis purposes.
A sample of 37 stars of luminosity classes I, III, V, including few SMRstars observed in the H band with a medium resolution (R=1500-2000) ispresented. This sample of flux calibrated spectra is intended to widenexisting stellar libraries. A new IR spectrograph, ISIS/IR, foreseen forCFHT has been used. Its main characteristics are briefly described.Stellar spectra obtained with this new spectrograph are compared tosimilar data obtained with the ESO NTT IRSPEC spectrograph. Thebehaviour of some prominent features is described and it is shown thatthe COλ1.60/SiIλ1.60 line ratio is a good luminosityindicator for stellar types later than K0.

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.

On the spectra and photometry of M-giant stars
From a sample of 97 very bright M-giant stars in the Solarneighbourhood, high-quality "intrinsic" spectra in the spectral range380 <~ λ[nm] <~ 900 for all M-spectral subtypes of the Caseand MK classification systems are obtained. The results are fitted tophotospheric synthetic spectra in the range 99 <~ λ [nm]<=12500 in order to infer the corresponding continua. The syntheticspectra are also compared to the intrinsic spectra. The effectivetemperatures are derived and mathematical spectral classificationcriteria are found. The (UB)_j_(VRI)_c_(JHKLM)_ESO_ photometric data ofthe sample are also given. The data are available on the StrasbourgAstronomical Data Centre (CDS).

Asymptotic giant branch stars near the sun
Available red and near-infrared photometry and apparent motions of M, S,and C asymptotic giant branch (AGB) stars in the Bright Star Catalogueare tabulated and discussed. It is shown that the red and near infraredindices normally used for late-type stars are interchangeable except forcarbon stars. The M-type giants are variable with visual amplitudegreater than 0.05 mag. The reddening-free parameter m2 from Genevaphotometry is essentially a temperature parameter for M giants, whilethe reddening-free parameter d is a sensitive detector of blue stellarcompanions. The space density of AGB stars near the sun decreases by afactor of 35 in a temperature range 3800 to 3400 K. Two of the S starsnear the sun were found to have nearly equal space motions and may becomembers of the Arcturus group.

Santiago Fundamental Catalogue - A catalogue of 1105 FK5 stars (equinox J2000.0)
The positions in right ascension and declination of 1105 FK5 stars,observed with a Meridian Circle during the period 1979 to 1991, aregiven. The average mean square error of a position, for the wholecatalog, is +/- 0.009 s in right ascension and +/- 0.10 arcsec indeclination. The mean epoch of the catalog is 1983.148.

Physical data of the fundamental stars.
Not Available

M Giant Populations and Galactic Structure
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990MNRAS.247..227F&db_key=AST

Southern JHKL standards
The basis for the current SAAO standard photometric system at JHKL isgiven. This depends on an extensive investigation involving 230 starsdistributed around the sky. The accuracy is estimated at + or - 0.02 magfor J, H and K and + or - 0.05 mag for L.

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.

UBV Photoelectric Photometry Catalogue (1986). III Errors and Problems on DM and HD Stars
Not Available

Santiago declination catalogue - A declination catalogue of 412 FK4 stars (equinox 1950.0)
This catalog contains the positions in declination, of 412 FK4 stars.The observations were carried out with the Repsold Meridian Circle atCerro Calan National Astronomical Observatory, during the period1963-1968. The average mean square error of one observation (for thewhole catalog) is + or - 0.13 arcsec. The mean epoch of observation ofthe catalog is 1965.75.

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.

Trigonometric parallax results for southern luminosity class III stars
New trigonometric parallaxes are reported for ten bright, southernlate-type MK giants ranging in spectral type from K0 to M3.5. The listincludes HR 794, 1247, 2245, 2773, 3518, 3803, 5287, 5603, 6832, and6913. The modern parallaxes are compared with earlier results, and theluminosity calibration for these stars is discussed. A list of giants ispresented containing the best prospects for future parallax work onlate-type MK giants.

Identification of the emission feature near 3.5 microns in the pre-main-sequence star HD 97048
(Previously announced in STAR as N82-34320)

Near infrared photometry. I - Homogenization of near-infrared data from southern bright stars
A single homogeneous data set containing near-infrared (JHKLM)photometry of bright stars in the Southern Hemisphere obtained fromdifferent sources is constructed based on the use of the Johnson systemas a standard. Data for 203 stars in the J, H, K and L bands and 87stars in the M band from the lists of Glass (1974), Engels et al.(1981), Wamsteker (1981) and Allen (1981, 1982) was combined bycomparison with the list of Johnson, followed by transformation into theJohnson J and K bands, the H band of Glass and Allen, an L band similarto that of Johnson but having the zero point of Glass, and the M band ofEngels. Average colors and spectral types are also obtained. The presentlist may be used to provide calibration objects in the range 1.2 to 5microns covering a wide range in color and brightness.

Enviar un nou article


Enllaços Relacionats

  • - No s'ha trobat enllaços -
Enviar un nou enllaç


Membre dels grups següents:


Dades d'Observació i Astrometria

Constel·lació:Chamaleon
Ascensió Recta:10h35m28.10s
Declinació:-78°36'28.0"
Magnitud Aparent:4.11
Distancia:126.743 parsecs
Moviment propi RA:-37.6
Moviment propi Dec:11.4
B-T magnitude:6.186
V-T magnitude:4.277

Catàlegs i designacions:
Noms PropisXiǎodǒusān
  (Edit)
Bayerγ Cha
HD 1989HD 92305
TYCHO-2 2000TYC 9401-1714-1
USNO-A2.0USNO-A2 0075-02404702
BSC 1991HR 4174
HIPHIP 51839

→ Sol·licitar més catàlegs i designacions de VizieR