A far-infrared survey of bow shocks and detached shells around AGB stars and red supergiants (Corrigendum)

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.

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Evolved massive stars at low-metallicity

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935916 ◽

2019 ◽

Vol 629 ◽

pp. A91 ◽

Cited By ~ 6

Author(s):

Ming Yang ◽

Alceste Z. Bonanos ◽

Bi-Wei Jiang ◽

Jian Gao ◽

Panagiotis Gavras ◽

...

Keyword(s):

Massive Star ◽

Far Infrared ◽

Asymptotic Giant Branch ◽

Initial Mass ◽

Agb Stars ◽

Proper Motions ◽

Future Studies ◽

Low Metallicity ◽

Different Color ◽

Yellow Supergiant

We present a clean, magnitude-limited (IRAC1 or WISE1 ≤ 15.0 mag) multiwavelength source catalog for the Small Magellanic Cloud (SMC) with 45 466 targets in total, with the purpose of building an anchor for future studies, especially for the massive star populations at low-metallicity. The catalog contains data in 50 different bands including 21 optical and 29 infrared bands, retrieved from SEIP, VMC, IRSF, AKARI, HERITAGE, Gaia, SkyMapper, NSC, Massey (2002, ApJS, 141, 81), and GALEX, ranging from the ultraviolet to the far-infrared. Additionally, radial velocities and spectral classifications were collected from the literature, and infrared and optical variability statistics were retrieved from WISE, SAGE-Var, VMC, IRSF, Gaia, NSC, and OGLE. The catalog was essentially built upon a 1″ crossmatching and a 3″ deblending between the Spitzer Enhanced Imaging Products (SEIP) source list and Gaia Data Release 2 (DR2) photometric data. Further constraints on the proper motions and parallaxes from Gaia DR2 allowed us to remove the foreground contamination. We estimate that about 99.5% of the targets in our catalog are most likely genuine members of the SMC. Using the evolutionary tracks and synthetic photometry from MESA Isochrones & Stellar Tracks and the theoretical J − KS color cuts, we identified 1405 red supergiant (RSG), 217 yellow supergiant, and 1369 blue supergiant candidates in the SMC in five different color-magnitude diagrams (CMDs), where attention should also be paid to the incompleteness of our sample. We ranked the candidates based on the intersection of different CMDs. A comparison between the models and observational data shows that the lower limit of initial mass for the RSG population may be as low as 7 or even 6 M⊙ and that the RSG is well separated from the asymptotic giant branch (AGB) population even at faint magnitude, making RSGs a unique population connecting the evolved massive and intermediate stars, since stars with initial mass around 6 to 8 M⊙ are thought to go through a second dredge-up to become AGB stars. We encourage the interested reader to further exploit the potential of our catalog.

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MSX Sources in the LMC: Dust-Enshrouded AGB Stars, Post-AGB Stars and PN

Symposium - International Astronomical Union ◽

10.1017/s0074180900208061 ◽

2003 ◽

Vol 209 ◽

pp. 52-52

Author(s):

P. R. Wood ◽

M. Cohen

Keyword(s):

Near Infrared ◽

Point Sources ◽

Agb Stars ◽

Large Numbers ◽

Red Supergiants ◽

Selection Of

The Midcourse Space (MSX) Experiment (Price 1995) detected large numbers of point sources in the LMC at 8.28 μm (Egan et al. 2001). Near-infrared J H K L imaging and monitoring of the 504 MSX sources in a region of size 3° x 3.5° covering most of the LMC bar has been carried out. Spectra have been taken for most of the post-AGB stars and a selection of the AGB stars and red supergiants.

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Rapid grain growth in post-AGB disc systems from far-infrared and sub-millimetre photometry

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa425 ◽

2020 ◽

Vol 494 (2) ◽

pp. 2925-2936

Author(s):

P Scicluna ◽

F Kemper ◽

A Trejo ◽

J P Marshall ◽

S Ertel ◽

...

Keyword(s):

Grain Growth ◽

Time Scales ◽

Far Infrared ◽

Asymptotic Giant Branch ◽

Growth Time ◽

Agb Stars ◽

Keplerian Orbits ◽

Dust Evolution ◽

Astronomical Dust ◽

Protoplanetary Discs

ABSTRACT The time-scales on which astronomical dust grows remain poorly understood, with important consequences for our understanding of processes like circumstellar disc evolution and planet formation. A number of post-asymptotic giant branch (AGB) stars are found to host optically thick, dust- and gas-rich circumstellar discs in Keplerian orbits. These discs exhibit evidence of dust evolution, similar to protoplanetary discs; however, since post-AGB discs have substantially shorter lifetimes than protoplanetary discs, they may provide new insights on the grain-growth process. We examine a sample of post-AGB stars with discs to determine the far-infrared and sub-millimetre spectral index by homogeneously fitting a sample of data from Herschel, the Submillimeter Array (SMA), and the literature. We find that grain growth to at least hundreds of micrometres is ubiquitous in these systems, and that the distribution of spectral indices is more similar to that of protoplanetary discs than debris discs. No correlation is found with the mid-infrared colours of the discs, implying that grain growth occurs independently of the disc structure in post-AGB discs. We infer that grain growth to ∼millimetre sizes must occur on time-scales <<105 yr, perhaps by orders of magnitude, as the lifetimes of these discs are expected to be ≲105 yr and all objects have converged to the same state. This growth time-scale is short compared to the results of models for protoplanetary discs including fragmentation and may provide new constraints on the physics of grain growth.

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Visual and Near-Infrared Photometry of Nearby Dwarf Spheroidals

Symposium - International Astronomical Union ◽

10.1017/s0074180900204506 ◽

1999 ◽

Vol 192 ◽

pp. 455-458 ◽

Cited By ~ 1

Author(s):

F. Kerschbaum ◽

W. Nowotny ◽

J. Hron ◽

M. Schultheis

Keyword(s):

Near Infrared ◽

Broad Band ◽

Feasibility Studies ◽

Asymptotic Giant Branch ◽

Agb Stars ◽

Faint Object ◽

Nearby Galaxies ◽

Dwarf Spheroidals ◽

Faint Object Spectrograph ◽

Infrared Survey

This paper is based on photometry from two different observational approaches. Both are of an explorative character and act as feasibility studies. For the future we plan to use these methods to study Asymptotic Giant Branch (AGB) stars in nearby galaxies.First, we present results on broad-band photometry in Bessell V and I, as well as narrow-band measurements in the Wing 778 nm and 812 nm filters of a galactic globular cluster using the new Austrian Oe-FOSC (Oesterreich Faint Object Spectrograph and Camera), a copy of the ESO Instrument EFOSC mounted on our 1.5 m-telescope.The second part of the contribution deals with the possibilities of using Gunn I, J and KS measurements originating from the DENIS (DEep Near Infrared Survey of the Southern Sky) project on similar objects. A few southern dwarf spheroidals already observed within DENIS (covering now some 40% of the southern hemisphere) are selected.

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A Cryogenically-Cooled, Balloon-Borne Far Infrared Survey Telescope

10.1117/12.957080 ◽

1979 ◽

Author(s):

Murray F. Campbell

Keyword(s):

Far Infrared ◽

Infrared Survey

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On the atmospheric structure and fundamental parameters of red supergiants

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314006930 ◽

2014 ◽

Vol 9 (S307) ◽

pp. 280-285

Author(s):

M. Wittkowski ◽

B. Arroyo-Torres ◽

J. M. Marcaide ◽

F. J. Abellan ◽

A. Chiavassa ◽

...

Keyword(s):

Water Vapor ◽

Near Infrared ◽

Unsolved Problem ◽

Agb Stars ◽

Fundamental Parameters ◽

Atmospheric Structure ◽

Spatially Extended ◽

Red Supergiants ◽

Hydrostatic Model ◽

Molecular Layers

AbstractWe present near-infrared spectro-interferometric studies of red supergiant (RSG) stars using the VLTI/AMBER instrument, which are compared to previously obtained similar observations of AGB stars. Our observations indicate spatially extended atmospheric molecular layers of water vapor and CO, similar as previously observed for Mira stars. Data of VY~CMa indicate that the molecular layers are asymmetric, possibly clumpy. Thanks to the spectro-interferometric capabilities of the VLTI/AMBER instrument, we can isolate continuum bandpasses, estimate fundamental parameters of our sources, locate them in the HR diagram, and compare their positions to recent evolutionary tracks. For the example of VY CMa, this puts it close to evolutionary tracks of initial mass 25-32 M⊙. Comparisons of our data to hydrostatic model atmospheres, 3d simulations of convection, and 1d dynamic model atmospheres based on self-excited pulsation models indicate that none of these models can presently explain the observed atmospheric extensions for RSGs. The mechanism that levitates the atmospheres of red supergiant is thus a currently unsolved problem.

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Far-infrared survey of the galactic plane

The Astrophysical Journal ◽

10.1086/183302 ◽

1980 ◽

Vol 239 ◽

pp. L101 ◽

Cited By ~ 14

Author(s):

T. Nishimura ◽

F. J. Low ◽

R. F. Kurtz

Keyword(s):

Galactic Plane ◽

Far Infrared ◽

Infrared Survey

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OH mainline maser polarisation properties of post-AGB stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312007053 ◽

2012 ◽

Vol 8 (S287) ◽

pp. 250-251

Author(s):

Jessica M. Chapman ◽

Ioannis Gonidakis ◽

Rachel M. Deacon ◽

Anne Green

Keyword(s):

Far Infrared ◽

Agb Stars ◽

Evolved Stars

AbstractThe Parkes 64-m telescope was used to study the OH mainline polarisation properties at 1665 and 1667 MHz for a sample of 36 evolved stars, identified by their far-infrared and OH 1612 MHz maser properties as likely post-AGB stars.

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