Capabilities of the AFGL mosaic array spectrometer - Ten-micron spectra of bright infrared stars

1990 ◽  
Vol 102 ◽  
pp. 190 ◽  
Author(s):  
Paul D. Levan
Keyword(s):  
1998 ◽  
Vol 11 (1) ◽  
pp. 395-395
Author(s):  
S. Nishida ◽  
T. Tanabé ◽  
S. Matsumoto ◽  
T. Onaka ◽  
Y. Nakada ◽  
...  

A systematic near-infrared survey was made for globular clusters in the Magellanic Clouds. Two infrared stars were discovered in NGC419 (SMC) and NGC1783 (LMC). NGC419 and NGC1783 are well-studied rich globular clusters whose turn-off masses and ages are estimated MTO ~ 2.0 Mʘ and т ~1.2 Gyr for NGC419, and MT0 ~ 2.0 Mʘ and т ʘ 0.9 Gyr for NGC1783, respectively. The periods of the infrared light variations were determined to be 540 dfor NGC419IR1 and to be 480 d for NGC1783IR1, respectively. Comparison of the measurements with the period—if magnitude relation for carbon Miras in the LMC by Groenewegen and Whitelock(1996) revealed that the Kmagnitudes of the infrared stars were fainter by about 0.3 — 0.8 magnitude than those predicted by the P — K relation. This deviation can be explained if the infrared stars are surrounded by thick dust shells and are obscured even in the K band. The positions of NGC419IR1and NGC1783IR1 on the P — K diagram suggest that AGB stars with the main sequence masses of about 2 Mʘ start their heavy mass-loss when P ʘ 500 d.


1974 ◽  
pp. 183-197
Author(s):  
JOHN S. GLASBY
Keyword(s):  

1975 ◽  
Vol 67 ◽  
pp. 175-177
Author(s):  
V. V. Burdjuzha ◽  
T. V. Ruzmaikina

Supergiant infrared stars with OH maser emissions, like NML Cyg, VY CMa, and VX Sgr, are discussed assuming a model consisting of a star with a photospheric temperature of about 2000 K and a radius of R ∼ 2 × 1014 cm surrounded by a gas and dust shell. A possible similarity with OH Miras is mentioned.


1974 ◽  
Vol 190 ◽  
pp. 339 ◽  
Author(s):  
R. M. Humphreys ◽  
E. P. Ney

1971 ◽  
Vol 169 ◽  
pp. L123 ◽  
Author(s):  
Ellen G. Hardebeck ◽  
William J. Wilson
Keyword(s):  

1971 ◽  
Vol 15 ◽  
pp. 32-34
Author(s):  
A. Kruszewski ◽  
J. Smak

We know several infrared objects showing large intrinsic polarization (FORBES 1967, APPENZELLER and O’DELL 1967, KRUSZEWSKI 1968, SERKOWSKI 1969, SHAWL 1969, SHAWL and ZELLNER 1970, KRUSZEWSKI 1971, DYCK, FORBES and SHAWL 1971).In the following discussion I shall speak about the broad category of infrared stars which consists of reddest and coolest giants (M8 or later) and supergiants (M5 or later). This restriction is made because the yellow supergiants seem to have different polarization properties and these properties most likely extend to supergiants as late as M 2 or even M 4. Also it is not clear if normal red variables can be treated together with infrared objects.


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