Оглавление
Изображения
Загрузить ваше изображение
DSS Images Other Images
Публикации по объекту
The Small Magellanic Cloud in the far infrared. I. ISO's 170 mu m map and revisit of the IRAS 12-100 mu m data
The ISOPHOT experiment onboard the ISO satellite generated a completeview of the Small Magellanic Cloud (SMC) at 170 mu m with 1.5 arcminresolution. The map is analysed using an automated photometry programenabling accurate photometric characterization of the far infrared (FIR)emitting regions. An integrated FIR luminosity of 8.5x 107Lsun is obtained, leading to a star formation rate ofSFRFIR=0.015 Msun/yr. With an average dusttemperature of , the total dustmass follows to MD=3.7x105 Msun. Inthis paper, the sources detected at 170 mu m are compared with thoseobtainable from the IRAS satellite data. For this purpose, the 12 mu m,25 mu m, 60 mu m, and 100 mu m IRAS high resolution (HiRes) maps of theSMC are re-examined using the same method. In contrast to formerstudies, this provides an all-band ISO/IRAS source catalog which is nolonger based on eyeball classification, but relies on an algorithm whichis capable of automated, repeatable photometry, even for irregularsources. In the mid infrared IRAS bands numerous bright FIR emittingregions in the SMC are detected and classified: 73 sources are found at12 mu m, 135 at 25 mu m (most of them with Fnu <1.0 Jy).All three FIR bands at 170 mu m, 100 mu m, and 60 mu m reproduce theoverall morphological structure of the SMC similarly well, in contrastto the 12 mu m and 25 mu m maps which only contain a limited number ofextended sources and do not trace the main body of the SMC. 243 sourcesare detected in the ISO 170 mu m map, 155 of them with Fnu>=2.0 Jy. Comparable numbers are found for the two FIR IRASmaps at 60 mu m (384) and 100 mu m (338) with fluxes up to 450 Jy. 70 ofthe 243 170 mu m sources are assigned a general SED type (``cold'',``warm'', i.e., <30 K, >30 K) for the first time. A comparisonwith earlier IRAS results suggests that many source flux densities inthose studies have been under- or overestimated because ofnon-standardized fitting methods. Many sources with flux densities up to40 Jy listed in former catalogs cannot be identified in our data.Based on observations with ISO, an ESA project with instruments fundedby ESA Member States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.The tables in Appendices A to E are only 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/401/873}
| Obscured AGB stars in the Magellanic Clouds. I. IRAS candidates
We have selected 198 IRAS sources in the Large Magellanic Cloud, and 11in the Small Magellanic Cloud, which are the best candidates to bemass--loosing AGB stars (or possibly post--AGB stars). We used thecatalogues of \cite[Schwering \& Israel (1990)]{ref42} and\cite[Reid et al. (1990)]{ref36}. They are based on the IRAS pointedobservations and have lower detection limits than the Point SourceCatalogue. We also made cross-identifications between IRAS sources andoptical catalogues. Our resulting catalogue is divided in 7 tables.Table \ref{tab1} lists optically known red supergiants and AGB stars forwhich we found an IRAS counterpart (7 and 52 stars in the SMC and LMC,respectively). Table \ref{tab2} lists ``obscured'' (or ``cocoon'') AGBstars or late-type supergiants which have been identified as such inprevious works through their IRAS counterpart and JHKLM photometry (2SMC and 34 LMC sources; no optical counterparts). Table \ref{tab3} listsknown planetary nebulae with an IRAS counterpart (4 SMC and 19 LMC PNe).Table \ref{tab4} lists unidentified IRAS sources that we believe to begood AGB or post--AGB or PNe candidates (11 SMC and 198 LMC sources).Table~\ref{tab5} lists unidentified IRAS sources which could be any typeof object (23 SMC and 121 LMC sources). Table \ref{tab6} lists IRASsources associated with foreground stars (29 SMC and 135 LMC stars).Table \ref{tab7} lists ruled out IRAS sources associated with HIIregions, hot stars, etc... We show that the sample of IRAS AGB stars inthe Magellanic Clouds is very incomplete. Only AGB stars more luminousthan typically 10^4 L_\odot and with a mass-loss rate larger thantypically 5 10^{-6} M_\odot/yr could be detected by the IRAS satellite.As a consequence, one expects to find very few carbon stars in the IRASsample. We also expect that most AGB stars with intermediate mass--lossrates have not been discovered yet, neither in optical surveys, nor inthe IRAS survey. Tables 1 to 8 are also available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| Positional reference stars in the Magellanic Clouds
The equatorial coordinates are determined of 926 stars (mainly ofgalactic origin) in the direction of the Magellanic Clouds at the meanepoch T = 1978.4 with an overall accuracy characterized by the meanvalues of the O-C coordinates, Sa = 0.35 arcsec and Sd = 0.38 arcsec,calculated from the coordinates of the Perth reference stars. Thesevalues are larger than the accuracy expected for primary standard stars.They allow the new positions to be considered as those of reliablesecondary standard stars. The published positions correspond to anunquestionable improvement of the quality of the coordinates provided inthe current catalogs. This study represents an 'astrometric step' in thestarting of a 'Durchmusterung' of the Magellanic Clouds organized by deBoer (1988, 1989).
| Infrared observations of the Magellanic Clouds. I - The Small Magellanic Cloud
Results of IRAS pointed observations in four infrared wavelength bands(12, 25, 60, and 100 microns) for the SMC are presented. Maps withorthogonal scan directions are shown, and a source list containing 219infrared sources is extracted from the data. Comparison with the IRASPoint Source Catalog (PSC) shows that only three entries in this catalogare spurious. All 13 entries in the IRAS Small Scale Structure Catalog(SSS) in the SMC are confirmed. Seventy-two new infrared sources, notincluded in either the PSC or in the SSS are found. The present SMCinfrared source list is compared to other object lists. Two blueglobular clusters, 28 SAO stars, and seven planetary nebulae areidentified. No SMC stars are found. In general there is a goodcorrelation of infrared emission with the distributiion of H II regionsand dark clouds.
| Sir John Herschel's Observations of Stars in the Small Magellanic Cloud
Not Available
| A sample of old-disk-population red giants.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88..426E&db_key=AST
| Starlight polarization in the Magellanic cloud regions.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...24..357S&db_key=AST
| Photometry of bright stars in the Small Magellanic Cloud.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&A.....9...95D&db_key=AST
| Fundamental data for southern stars (First list)
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1957MNRAS.117..534E&db_key=AST
|
Добавить новую статью
Внешние ссылки
- - Внешних ссылок не найдено -
Добавить внешнюю ссылку
Группы:
|
Наблюдательные данные и астрометрия
| Созвездие: | Тукан |
| Прямое восхождение: | 01h05m07.94s |
| Склонение: | -71°44'02.2" |
| Видимая звёздная величина: | 7.364 |
| Расстояние: | 236.967 парсек |
| Собственное движение RA: | 103.7 |
| Собственное движение Dec: | 47.5 |
| B-T magnitude: | 8.777 |
| V-T magnitude: | 7.481 |
Каталоги и обозначения:
|
