J/A+A/614/A12 VLTI/PIONIER observations of CE Tauri (Montarges+, 2018)
The convective photosphere of the red supergiant CE Tauri.
I. VLTI/PIONIER H band interferometric imaging.
Montarges M., Norris R., Chiavassa A., Tessore B., Lebre A., Baron F.
<Astron. Astrophys. 614, A12 (2018)>
=2018A&A...614A..12M 2018A&A...614A..12M (SIMBAD/NED BibCode)
ADC_Keywords: Interferometry ; Stars, supergiant ; Stars, M-type ;
Stars, late-type
Keywords: stars: individual: CE Tau - stars: imaging - supergiants -
stars: mass-loss - infrared: Stars - techniques: interferometric
Abstract:
Red supergiant stars represent one of the latest stages of the
evolution of massive stars. Their photospheric convection may play an
important role in the launching mechanism of their mass loss. Yet, its
characteristics and dynamics are poorly constrained.
By observing red supergiant stars with near infrared interferometry at
different epochs, we expect to unveil the evolution of bright
convective features on their stellar surface.
We observed the M2Iab-Ib red supergiant star CE Tau with the
VLTI/PIONIER instrument in the H band at two different epochs
separated by one month.
We derive the angular diameter of the star, basic stellar parameters
and reconstruct two reliable images of its H band photosphere. The
contrast of the convective pattern of the reconstructed images is
5±1% and 6±1 % for our two epochs of observation.
The stellar photosphere shows few changes between the two epochs. The
contrast of the convective pattern is below the average contrast
variations obtained on 30 randomly chosen snapshots of the best
matching 3D radiative hydrodynamics simulation: 23±1% for the
original simulation images, and 16±1% for the maps degraded to
the reconstruction resolution. We offer two hypotheses to explain this
observation: CE Tau may be experiencing a quiet convective activity
episode or it could be a consequence of its warmer effective
temperature (hence its smaller radius) compared to the simulation.
Description:
Reconstructed images obtained with the SQUEEZE algorithm on the red
supergiant star CE Tauri from VLTI/PIONIER observations and derived
basic stellar parameters
Objects:
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RA (2000) DE Designation(s)
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05 32 12.75 +18 35 39.2 CE Tau = * 119 Tau
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stel_par.dat 107 2 Stellar parameters compiled from Sect. 4.1.2 of
the article
list.dat 97 4 List of fits images
fits/* . 4 Individual fits images
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Byte-by-byte Description of file: stel_par.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Name Name of the star
8- 10 A3 --- Month Month of observation
12- 15 I4 --- Year Year of observation
17- 19 I3 Rsun Radius Stellar radius
21- 22 I2 Rsun e_Radius Error on the stellar radius
24- 30 E7.2 W/m2 Fbol Bolometric flux
32- 39 E8.2 W/m2 e_Fbol Error on the bolometric flux
41- 44 I4 K Teff Effective temperature
46- 48 I3 K e_Teff Error on the effective temperature
50- 53 F4.2 [Lsun] logL Luminosity
55- 58 F4.2 [Lsun] e_logL Lower error on the luminosity
60- 63 F4.2 [Lsun] E_logL Upper error on the luminosity
65- 69 F5.2 Msun Mcur Current mass
71- 74 F4.2 Msun e_Mcur Lower error on the current mass
76- 79 F4.2 Msun E_Mcur Upper error on the current mass
81- 84 F4.2 [cm/s2] logg Effective gravity
86- 89 F4.2 [cm/s2] e_logg Lower error on the effective gravity
91- 94 F4.2 [cm/s2] E_logg Upper error on the effective gravity
96- 99 F4.1 Myr Age Age of the star
101-103 F3.1 Myr e_Age Lower error on the age
105-107 F3.1 Myr E_Age Upper error on the age
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 8 F8.5 deg RAdeg Right Ascension of center (J2000)
9- 17 F9.5 deg DEdeg Declination of center (J2000)
19- 20 I2 --- Nx Number of pixels along X-axis
22- 23 I2 --- Ny Number of pixels along Y-axis
25- 26 I2 Kibyte size Size of FITS file
28- 38 A11 --- FileName Name of FITS file, in subdirectory fits
40- 97 A58 --- Title Title of the FITS file
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Acknowledgements:
Miguel Montarges, miguel.montarges(at)obspm.fr
(End) Miguel Montarges [KU Leuven, Belgium], Patricia Vannier [CDS] 07-Feb-2018