J/AJ/166/73 Line identifications for α Sex (Monier+, 2023)
The Unexpected Optical and Ultraviolet Variability of the Standard Star.
Monier R., Bowman D.M., Lebreton Y., Deal M.
<Astron. J., 166, 73 (2023)>
=2023AJ....166...73M 2023AJ....166...73M
ADC_Keywords: Stars, A-type; Abundances; Optical
Keywords: A giant stars
Abstract:
The analysis of the available Transiting Exoplanet Survey Satellite
(TESS) light curves of αSex (HD87887) reveals low-frequency
pulsations with a period of about 9.1hr in this spectroscopic A0III
standard star. The IUE observations in 1992 December reveal large flux
variations both in the far-UV and in the mid-UV, which are accompanied
by variations of the brightness in the V band recorded by the the Fine
Error Sensor on board IUE. The ultraviolet variability could be due to
an eclipse by an hitherto undetected companion of smaller radius,
possibly 2.5R☉, but this needs confirmation by further monitoring
possibly with TESS. An abundance determination yields solar abundances
for most elements. Only carbon and strontium are underabundant and
titanium, vanadium, and baryum mildly overabundant. Identification is
provided for most of the lines absorbing more than 2% in the optical
spectrum of αSex. Stellar evolution modeling shows that
αSex is near the terminal-age main sequence, and its mass,
radius, and age are estimated to be M=2.57±0.32M☉,
R=3.07±0.90R☉, A=385±77Myr, respectively.
Description:
The TESS mission observed αSex in sectors 8, 35 and 45 in its
short cadence (i.e., 2 minutes) mode. We retrieved both the simple
aperture photometry (SAP) and predata search conditioning (PDC-SAP)
2minute light curves from the Mikulski Archive for Space Telescopes,
which are extracted from the target pixel files using NASA's SPOC
pipeline.
Objects:
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RA (2000) DE Designation(s)
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10 07 56.28 +00 22 18.0 HD87887 = * alf Sex
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 47 477 Line identifications for α Sex
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See also:
B/polarbase : PolarBase spectropolarimetric (ESPaDOnS, NARVAL) (Petit+, 2014)
II/215 : uvby-beta Catalogue (Hauck+ 1997)
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
J/ApJ/573/359 : Rotational velocities of B stars from BSC (Abt+, 2002)
J/A+A/393/897 : Rotational velocities of A-type stars II. (Royer+, 2002)
J/A+A/406/987 : Elemental abundances of three CP stars (Pintado+, 2003)
J/MNRAS/389/869 : Multiplicity among bright stellar systems (Eggleton+, 2008)
J/MNRAS/427/343 : Infrared excesses of Hipparcos stars (McDonald+, 2012)
J/PASP/126/469 : PolarBase catalogue of stellar spectra (Petit+, 2014)
J/AJ/153/16 : Calibrator stars cat. for interferometers (Swihart+, 2017)
J/MNRAS/490/4040 : δScuti & γDoradus stars in TESS (Antoci+, 2019)
J/other/NatAs/3.760 : Blue supergiants low-freq gravity waves (Bowman+, 2019)
J/A+A/623/A72 : Bin Hipparcos stars from Gaia pm anomaly (Kervella+, 2019)
J/MNRAS/485/2380 : Gaia-derived luminosities Kepler A/F stars (Murphy+, 2019)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 F8.3 0.1nm OWave [3900/6679]? Observed wavelength; Angstroms
10- 17 F8.3 0.1nm LWave [3900/6679]? Laboratory wavelength; Angstroms
19- 24 A6 --- Species Species identifier
26- 31 F6.3 [-] loggf [-4.29/1.16]? log oscillatory strength
33- 42 F10.3 --- Elow [0/199942]? Lower energy
44- 47 A4 --- Ref Reference
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 12-Mar-2024