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Uva-DARE (Digital Academic Repository) UvA-DARE (Digital Academic Repository) Mass loss and evolution of asymptotic giant branch stars in the Magellanic Clouds van Loon, J.T. Publication date 1999 Link to publication Citation for published version (APA): van Loon, J. T. (1999). Mass loss and evolution of asymptotic giant branch stars in the Magellanic Clouds. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:27 Sep 2021 Chapterr 7 ISOO observations of obscured Asymptoticc Giant Branch stars in the Largee Magellanic Cloud NormanNorman R. Trams, Jacco Th. van Loon, L.B.F.M. Waters, Albert A. Zijlstra, Cecile Loup, PatriciaPatricia A. Whitelock, M.A.T. Groenewegen, Joris A.D.L. Blommaert, Ralf Siebenmorgen, A. Heske,Heske, Michael W. Feast, 1999, A&A Main Journal in press Wee present ISO photometric and spectroscopic observations of a sample of 57 bright Asymptotic Giantt Branch stars and red supergiants in the Large Magellanic Cloud, selected on the basis of IRASS colours indicative of high mass-loss rates. PHOT-P and PHOT-C photometry at 12, 25 andd 60 ^m and CAM photometry at 12 /xm are used in combination with quasi-simultaneous ground-basedd near-IR photometry to construct colour-colour diagrams for all stars in our sam- ple.. PHOT-S and CAM-CVF spectra in the 3 to 14 /im region are presented for 23 stars. From thee colour-colour diagrams and the spectra, we establish the chemical types of the dust around 499 stars in this sample. Many stars have carbon-rich dust. The most luminous carbon star in thee Magellanic Clouds has also a (minor) oxygen-rich component. OH/IR stars have silicate absorptionn with emission wings. The unique dataset presented here allows a detailed study of aa representative sample of thermal-pulsing AGB stars with well-determined luminosities. 7.11 Introduction Onee of the least expected achievements of the Infra-Red Astronomical Satellite (IRAS; Neuge- bauerr et al. 1984) was the detection of a large number of mid-IR point sources in the Large Magellanicc Cloud (LMC) just above its limits of sensitivity (IRAS Point Source Catalogue; Schweringg k Israel 1990). Many of these are candidates for intermediate-mass stars at the tip off the Asymptotic Giant Branch (AGB). Their lives drawing to a close, these stars are shedding 4 -1 theirr stellar mantles at rates of up to 10~ M0 yr . Their dusty circumstellar envelopes (CSEs) obscuree the optical light from the star and become very bright IR objects. The details of the evolutionn and mass loss of AGB stars are poorly understood. The study of galactic samples off AGB stars is severely hampered by the difficulty to determine accurate distances to stars in thee Milky Way. The distance to the LMC, however, is well known and hence luminosities and mass-losss rates of AGB stars in the LMC may be determined with a high degree of accuracy. 81 1 82 2 ChapterChapter 7 Tablee 7J IRAS detected stars observed with ISO: names (LI stands for LI-LMC (Schwering & Israel 1990), TRM is from Reid et al. (1990), HV iss from Payne-Gaposchkin (1971), SP is from Sanduleak & Philip (1970) and WOH is from Westerlund et al. (1981); sources will be referenced hereafterr by their bold-faced names), ISO pointing coordinates (J2000), and references: 1: Hodge & Wright (1969); 2: Eggen (1971); 3: Wright && Hodge (1971); 4: Dachs (1972); 5: Sandage & Tammann(1974); 6: Glass (1979); 7: Humphreys (1979); 8: Blanco et al. (1980); 9: Feast el al.(1980);; 10: Bessell & Wood (1983); 11: Wood et al. (1983); 12: Rebeirot et al. (1983); 13: Prevot et al (1985); 14: Elias et al. (1985); 15: Woodett al. (1985); 16: Elias et al (1986); 17: Woodet al. (1986); 18: Reid et al. (1988); 19: Reid (1989); 20: Hughes (1989); 21: Hughes & Woodd (1990); 22: Reid et al. (1990); 23: Hughes et al. (1991); 24: Wood et al. (1992); 25: Roche et al. (1993); 26: Groenewegen et al (1995); 27:: Zijlstra et al. (1996); 28: Ritossaet al. (1996); 29: van Loon et al. (1996); 30: van Loon et al. (1997); 31: Loup et al. (1997); 32: Oestreicher (1997);; 33: van Loonet al. (1998a); 34: Groenewegen & Blommaert (1998); 35: van Loon el al. (1998b); 36: van Loon et al. (1999) LI I IRAS S TRM M HV V RAA (2000) Decll (2000) Otherr names References s IRASIRAS detected stars 1825 5 04286-6937 7 -- -- 044 28 30.3 -699 3049 -- 27.31,33 3 1844 4 04374-6831 1 -- -- 044 37 22.8 -688 25 03 -- 27,31,33 3 4 4 04407-7000 0 -- -- 044 40 28.4 -699 55 13 -- 27,31,33 3 57 7 04496-6958 8 -- -- 044 49 18.6 -699 53 14 -- 27,31,33,34,36 6 60 0 04498-6842 2 -- -- 044 49 41.4 -688 37 50 -- 27,31,33,36 6 77 7 04509-6922 2 -- -- 044 50 40.2 -699 17 33 -- 24.27.28,33,36 6 92 2 04516-6902 2 -- -- 044 51 28.4 -688 57 53 -- 24,27,33 3 121 1 04530-6916 6 -- -- 044 52 45.3 -699 1153 -- 24.27.28 8 141 1 04539-6821 1 -- -- 044 53 46.3 -688 16 12 -- 27.31,33 3 153 3 04544-6849 9 -- -- 044 54 14.4 -688 44 13 SP777 30-6.WO HH SG66 12,13,20,21,27,31 1 159 9 04545-7000 0 -- -- 044 54 09.8 -699 56 00 -- 24.27 7 181 1 04553-6825 5 -- -- 044 55 10.1 -688 20 35 WOHG64 4 16,17,19,24,25,27.29.31.33.35,36 6 198 8 04557-6753 3 -- -- 044 55 38.9 -677 49 10 -- 27,31,33 3 203 3 04559-6931 1 -- 12501 1 044 55 41.6 -699 26 25 SP777 31-20,WO HH SG097 11,12.13,20,22,27.32,33 3 297 7 05003-6712 2 -- -- 055 00 18.9 -677 08 02 -- 27.30.31,33,36 6 310 0 05009-6616 6 -- -- 055 01 03.8 -666 1240 -- 27.31,33.36 6 383 3 05042-6720 0 48 8 888 8 055 04 14.3 -677 16 17 SP777 29-33.WO HH SGI40 5.6,7,11.14.18.22.31,32 2 570 0 05112-6755 5 4 4 -- 055 11 10.1 -677 52 17 -- 22,27.31.33.36 6 571 1 05113-6739 9 24 4 -- 055 11 13.7 -677 36 35 -- 22.27.31.33 3 578 8 -- 72 2 -- 055 11 41.2 -66511 12 -- 22,27.31.33 3 612 2 05128-6728 8 43 3 2360 0 055 12 46.4 -677 19 37 SP777 37-24,WO HH SGI93 3,5,6,7,11,14,18,22,31 1 1880 0 05128-6455 5 -- -- 055 13 04.6 -644 51 40 -- 27,31,33.36 6 663 3 05148-6730 0 36 6 916 6 055 14 49.9 -677 27 19 SP777 37-35,WO HH SG204 1,2,4,6,7,11,18,22,31,32 2 793 3 05190-6748 8 20 0 -- 055 18 56.7 -677 45 06 -- 22.27,31.33 3 -- -- 88 8 -- 055 20 20.9 -666 36 00 -- 22.27,31.33,34,36 6 -- -- 45 5 -- 055 28 16.3 -677 20 55 -- 22.27.31.33 3 1157 7 05295-7121 1 -- -- 055 28 40.8 -711 19 13 -- 27,31 1 1130 0 05289-6617 7 99 9 -- 055 29 02.6 -666 1531 -- 22.27.31 1 1145 5 -- -- 5870 0 055 29 03.5 -699 06 47 SP777 47-17.WO HH SG331 9,11,20,31 1 1153 3 05294-7104 4 -- -- 055 28 47.8 -71022 29 -- 24,27.33 1 1164 4 05298-6957 7 -- -- 055 29 24.5 -699 55 14 -- 24,27,31.36 6 1177 7 05300-6651 1 79 9 -- 055 30 04.2 -666 49 23 -- 22,27.31,36 6 1238 8 05316-6604 4 101 1 -- 055 31 45.9 -666 03 51 WOHH SG374 22,27.31 1 1281 1 05327-6757 7 5 5 996 6 055 32 36.0 -677 55 08 SP777 46-59,WO HH SG388 7,11,17,18,22.31 1 1286 6 05329-6708 8 60 0 -- 055 32 52.5 -677 06 25 -- 17,22.24,26,27,31.33.36 6 1345 5 05348-7024 4 -- -- 055 34 16.1 -700 22 53 -- 27,31,33 3 1382 2 05360-6648 8 77 7 -- 055 36 03.3 -666 4647 -- 22.27,31,33 3 1506 6 05402-6956 6 -- -- 055 39 44.6 -699 55 18 -- 24,27 7 1756 6 05506-7053 3 -- -- 055 50 09.1 -700 53 12 -- 27.31.33 3 1790 0 05558-7000 0 -- -- 055 55 20.8 -70000 05 -- 27,31 1 1795 5 05568-6753 3 -- -- 055 56 38.7 -677 53 39 -- 27,31 1 Earlyy explorations of the IRAS data in combination with ground-based near-IR observations resultedd in the first identifications of mid-IR sources in the LMC with obscured AGB stars (Reidd et al.
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