J/A+A/708/A343 B supergiants in the LMC (Kalari+, 2026)
The incidence of LBV variability in the Large Magellanic Cloud.
Kalari V.M., Vink J.S., Furey C., Salinas R., Udalski A., Pawlak M.
<Astron. Astrophys. 708, A343 (2026)>
=2026A&A...708A.343K 2026A&A...708A.343K (SIMBAD/NED BibCode)
ADC_Keywords: Magellanic Clouds ; Stars, variable ; Stars, B-type ;
Stars, supergiant ; MK spectral classification ; Optical
Keywords: stars: massive - stars: variables: S Doradus - Magellanic Clouds
Abstract:
Luminous blue variables (LBVs) exhibit unique variability features,
characterized by episodic outbursts (>1mag) accompanied by
spectroscopic changes (S Dor variables). It is debated if all massive
stars undergo an LBV-like phase during their evolution, or instead
LBVs are exotic phenomena.
We aim to quantify the incidence of LBV-like variability in the blue
supergiant (BSgs) population of the Large Magellanic Cloud (LMC) using
the OGLE survey.
Here, we extend previous work in the Small Magellanic Cloud to the
LMC, where we examine the light curves of 87 B Supergiants (BSgs) (out
of 254 known BSgs) spanning timescales of twenty years, and 37 objects
across a three year timescale for aperiodic variations resembling
known S Dor variables.
One blue supergiant, [ST92] 4-13, shows S Dor type photometric
variations. New spectra of this object reveals a potential change in
spectral type compared to the literature classification. However,
based on its spectral characteristics and low luminosity and mass, we
do not currently classify it as an LBV.
Our study highlights the need to classify bona fide LBVs as stars
undergoing both photometric and spectroscopic variations. Based on
currently known stellar population of S Dor variables in the LMC, the
lifetime of the S Dor phase is at most ∼103yrs, in agreement with
our duty cycle study based on OGLE data in the SMC. This is orders of
magnitude shorter than assumed in literature. Our discovery of
LBV-like variability at low luminosities may suggest that S,Dor
variations could arise from Eddington limit related physics over a
wide range of stellar masses, rather than being linked to a unique
evolutionary stage.
Description:
B supergiants in the Large Magellanic Cloud, including those having
multi- epoch OGLE or Gaia photometry. Coordinates are given in the
J2000 epoch. Survey ID refers to either the OGLE ID when the object
has OGLE data, or Gaia DR3 identifier when there is Gaia multi-epoch
photometry. ID refers to the identifier from Bonanos et al.
(2009AJ....138.1003B 2009AJ....138.1003B, Cat. J/AJ/138/1003).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 162 254 B supergiants in the Large Magellanic Cloud
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See also:
J/AJ/138/1003 : IR photometry of massive LMC stars (Bonanos+, 2009)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Name Object name
16- 32 F17.14 deg RAdeg Right Ascension (J2000)
34- 51 F18.14 deg DEdeg Declination (J2000)
53- 66 A14 --- SpType Spectral type
68- 81 A14 --- Survey OGLE/Gaia DR3
83-126 A44 --- SurveyID OGLE ID when the object has OGLE data, or
Gaia DR3 identifier when there is
Gaia multi-epoch photometry
128-157 A30 --- SName SIMBAD Name
159-162 I4 --- IDB09 Identified in Bonanos et al.
(2009AJ....138.1003B 2009AJ....138.1003B. Cat. J/AJ/138/1003)
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Acknowledgements:
Venu Kalari, venu.kalari(at)noirlab.edu
License: CC-BY-4.0 [see https://spdx.org/licenses/]
(End) Patricia Vannier [CDS] 25-Mar-2026