J/ApJ/747/108 Rigel. I. MOST photometry and RV monitoring (Moravveji+, 2012)
Asteroseismology of the nearby SN-II progenitor: Rigel.
I. The MOST high-precision photometry and radial velocity monitoring.
Moravveji E., Guinan E.F., Shultz M., Williamson M.H., Moya A.
<Astrophys. J., 747, 108 (2012)>
=2012ApJ...747..108M 2012ApJ...747..108M
ADC_Keywords: Photometry ; Radial velocities ; Stars, giant
Keywords: asteroseismology - techniques: spectroscopic -
stars: individual: Rigel - Sun: oscillations - supergiants
Abstract:
Rigel (β Ori, B8 Ia) is a nearby blue supergiant displaying
α Cyg type variability, and is one of the nearest Type II
supernova progenitors. As such it is an excellent test bed to study
the internal structure of pre-core-collapse stars. In this study, for
the first time, we present 28 days of high-precision MOST photometry
and over six years of spectroscopic monitoring. We report 19
significant pulsation modes of signal-to-noise ratio, S/N ≳ 4.6 from
radial velocities, with variability timescales ranging from 1.21 to
74.7 days, which are associated with high-order low-degree gravity
modes. While the radial velocity variations show a degree of
correlation with the flux changes, there is no clear interplay between
the equivalent widths of different metallic and Hα lines.
Description:
Rigel was observed continuously with the MOST (Microvariability and
Oscillations of Stars) satellite (350-700nm) for 27.7 days from 2009
November 15 to December 13.
Rigel's optical spectrum has been monitored by the 2m Tennessee State
University Automatic Spectroscopic Telescope at Fairborn Observatory,
AZ (TSU/AST). A total of 2328 high-resolution (R∼30000 and 20000)
moderate signal-to-noise ratio (S/N∼50-150) echelle spectra
(4900-7100Å) were obtained. The spectra were secured over 334
nights starting from 2003 December 11 to 2010 February 14. The density
of time sampling was increased during the months centered on the MOST
observations. Simultaneous with MOST, 442 spectra were collected over
20 nights.
In conjunction with MOST photometry, 78 observations were collected
with the high-resolution (R∼65000) spectropolarimeter ESPaDOnS,
installed at the Canada-France-Hawaii Telescope, and its clone Narval
at Telescope Bernard Lyot (TBL, Pic du Midi).
Objects:
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RA (2000) DE Designation(s) (Periods: shortest,longest)
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05 14 32.27 -08 12 05.9 Rigel = HD 34085 (P=1.219) (P=74.74)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
data1.dat 20 31150 MOST (Microvariability and Oscillations of Stars)
space photometry
data2.dat 25 2328 Full AST radial velocity data set (Automatic
Spectroscopic Telescope at Fairborn Observatory)
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See also:
J/ApJS/190/203 : 3.6 years of DIRBE NIR stellar light curves (Price+, 2010)
J/ApJ/535/325 : Spectra of normal stars in the J-band (Wallace+ 2000)
J/ApJS/111/445 : Spectra of normal stars in the K band (Wallace+ 1997)
Byte-by-byte Description of file: data1.dat
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Bytes Format Units Label Explanations
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1- 9 F9.4 d HJD Heliocentric Julian Date (HJD-2450000)
11- 20 F10.8 mmag Dmag Relative MOST observed magnitude
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Byte-by-byte Description of file: data2.dat
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Bytes Format Units Label Explanations
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1- 13 F13.5 d HJD Heliocentric Julian Date
15- 19 F5.2 km/s RVel Radial velocity (1)
21- 25 F5.3 km/s e_RVel Error in RVel
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Note (1): Calculated using a gaussfit of 29 metallic lines.
Some of the wavelengths have been adjusted to make the computed radial
velocity for that line consistent with the average for all the lines
in the spectra. A +0.3km/s offset for the AST is already added.
------------------------------------------------------------------------
line ID from
------------------------------------------------------------------------
5015.720 HeI # 5015.679 Saul Adelman B6IV list
5018.448 FeII # 5018.448 Saul Adelman B6IV list
5032.444
5040.993 SiII # 5040.993 Saul Adelman B6IV list
5047.691 HeI # 5047.749 Saul Adelman B6IV list
5056.038 SiII # 5055.988 Saul Adelman B6IV list
5127.546 Fe # 5127.51 Ewa Niemczura & Gerald Handler HD_886
5169.040 FeII # 5169.040 Saul Adelman B6IV list
5260.202
5316.551 FeII # 5316.620 solar
5428.654
5432.812 SII # 5432.8 Ewa Niemczura & Gerald Handler HD_886
5453.879 SII # 5453.851 Saul Adelman B6IV list
5473.600 S # 5473.6 Ewa Niemczura & Gerald Handler HD_886
5509.730 S # 5509.7 Ewa Niemczura & Gerald Handler HD_886
5564.975
5606.162
5640.110 SII # 5640.0 Ewa Niemczura & Gerald Handler HD_886
5647.050 SII # 5647.0 Ewa Niemczura & Gerald Handler HD_886
5659.990 SII # 5660.0 Ewa Niemczura & Gerald Handler HD_886
5875.776 HeI # 5875.618 Ewa Niemczura & Gerald Handler HD_886
5978.906
6143.069 Ne # 6143.063 Ewa Niemczura & Gerald Handler HD_886
6347.075 SiII # 6347.091 Underhill B6 list
6371.350 SiII # 6371.355 solar
6402.260 Ne # 6402.246 Ewa Niemczura & Gerald Handler HD_886
6578.113 CII # 6578.030 Underhill B6 list
6582.962 CII # 6582.850 Underhill B6 list
6678.224 HeI # 6678.149 Underhill B6 list
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History:
From electronic version of the journal
References:
Moravveji et al. Paper II. 2012ApJ...749...74M 2012ApJ...749...74M
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 27-Sep-2013