J/AJ/160/32 beta Cephei light curves from KELT project (Labadie-Bartz+, 2020)
New beta Cephei stars from the KELT project.
Labadie-Bartz J., Handler G., Pepper J., Balona L., De Cat P., Stevens D.J.,
Lund M.B., Stassun K.G., Rodriguez J.E., Siverd R.J., James D.J., Kuhn R.B.
<Astron. J., 160, 32 (2020)>
=2020AJ....160...32L 2020AJ....160...32L
ADC_Keywords: Surveys; Stars, variable; Photometry, VRI; Spectral types;
Asteroseismology
Keywords: Beta Cepheid variable stars ; Asteroseismology ;
Stellar oscillations ; Multi-periodic variable stars ;
Pulsating variable stars ; Short period variable stars ;
Early-type variable stars ; Light curves ;
Light curve classification ; Surveys ; B stars
Abstract:
We present the results of a search for Galactic β Cephei stars,
which are massive pulsating stars with both pressure modes and mixed
modes. Thus, these stars can serve as benchmarks for seismological
studies of the interiors of massive stars. We conducted the search by
performing a frequency analysis on the optical light curves of known
O- and B-type stars with data from the Kilodegree Extremely Little
Telescope exoplanet survey. We identify 113 β Cephei stars, of
which 86 are new discoveries, which altogether represent a 70%
increase in the number currently known. An additional 97 candidates
are identified. Among our targets, we find five new eclipsing binaries
and 22 stars with equal frequency spacings suggestive of rotational
splitting of nonradial pulsation modes. Candidates for runaway stars
among our targets and a number of interesting individual objects are
discussed. Most of the known and newly discovered β Cephei stars
will be observed by the Transiting Exoplanet Survey Satellite mission,
providing by far the most comprehensive observational data set of
massive main-sequence pulsating stars of sufficient quality for
detailed asteroseismic studies. Future analysis of these light curves
has the potential to dramatically increase our understanding of the
structure of stellar interiors and the physical processes taking place
therein.
Description:
The Kilodegree Extremely Little Telescope (KELT) is a photometric
survey designed to discover transiting exoplanets orbiting stars in
the magnitude range of 7≲V≲12, with light curves for ∼4.9 million
objects across ∼70% of the sky. The KELT survey employs two
small-aperture (42mm) wide-field (26°x26°) telescopes, with a
northern location at Winer Observatory in Arizona in the United
States, and a southern location at the South African Astronomical
Observatory near Sutherland, South Africa. The effective passband is
roughly equivalent to a broad R-band filter.
Raw data are the direct products of the difference imaging pipeline.
We also have a detrending procedure using the TFA algorithm from
Kovacs+ (2002A&A...391..369K 2002A&A...391..369K), which removes common trends to the data
analogous to the Kepler Cotrending Basis Vectors (CBVs).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 115 113 β Cephei stars identified in this work
table2.dat 115 97 Candidate β Cephei stars identified in this
work
table3.dat 115 31 Candidate β Cephei rejected in this work
tableb1.dat 52 477 Frequencies and amplitudes determined for the
β Cephei stars
tableb2.dat 52 221 Frequencies and amplitudes determined for the
candidate β Cephei stars
tableb3.dat 52 64 Frequencies and amplitudes determined for the
rejected stars
fig7/* . 409 Individual light curves in MRT format
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See also:
B/mk : Catalogue of Stellar Spectral Classifications (Skiff,2009- )
III/67 : Catalogue of Be stars (Jaschek+, 1982)
III/135 : Henry Draper Catalogue and Extension (Cannon+ 1918-1924; ADC 1989)
III/190 : WEB Catalog of Radial Velocities (Duflot+ 1995)
III/182 : HDE Charts: positions, proper motions (Nesterov+ 1995)
III/231 : The Tycho-2 Spectral Type Catalog (Wright+, 2003)
III/254 : 2nd Cat. of RVs with Astrometric Data (Kharchenko+, 2007)
III/260 : General Catalogue of Ap and Am stars (Renson+ 2009)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
J/AN/283/109 : Star positions in the region of alpha Per (Heckmann+, 1956)
J/A+A/286/136 : Radial velocities of four beta Cep variables (Aerts+, 1994)
J/A+AS/122/51 : B to G stars calibration in Geneva photometry (Kunzli+,1997)
J/A+A/368/912 : Polarization & rotational velocities Be stars (Yudin, 2001)
J/ApJ/573/359 : Rotational velocities of B stars from BSC (Abt+, 2002)
J/A+A/393/965 : Intrinsic frequencies of pulsating B stars (de Cat+, 2002)
J/MNRAS/331/45 : New periodic variables (Koen+, 2002)
J/A+A/415/241 : Geneva photometry of HD 129929 (Aerts+, 2004)
J/ApJS/158/193 : Catalog of Galactic β Cephei stars (Stankov+, 2005)
J/BaltA/14/1 : Vilnius photometry in a Cam area (Zdanavicius+, 2005)
J/ApJ/648/580 : Rotational velocities in 19 open clusters (Huang+, 2006)
J/AJ/134/1570 : Rotational velocities of OB stars (Daflon+, 2007)
J/A+A/463/243 : Variations of O-B stars in Mercator obs. (De Cat+, 2007)
J/AN/328/889 : Mean Radial Velocities of open clusters (Kharchenko+, 2007)
J/A+A/477/917 : Beta Cephei stars in the ASAS-3 data. II. (Pigulski+, 2008)
J/A+A/506/111 : Frequency analysis of HD 180642 (V1449 Aql) (Degroote+,2009)
J/AJ/138/813 : Speckle interferometer at Mount Wilson Obs. (Hartkopf+,2009)
J/A+A/506/95 : Fourier analysis of HD 49330 CoRoT light curve (Huat+, 2009)
J/ApJS/186/191 : VI photometry and spectroscopy in h+χ Per (Currie+,2010)
J/ApJ/722/605 : A stellar rotation census of B stars (Huang+, 2010)
J/A+A/533/A70 : New β Cep stars in NGC 637 (Handler+, 2011)
J/MNRAS/410/190 : Young runaway stars within 3kpc (Tetzlaff+, 2011)
J/AJ/144/130 : Rotational velocities of nearby HIP B stars (Braganca+,2012)
J/MNRAS/424/1925 : Spectrocopic Binarity of O and B type stars (Chini+, 2012)
J/AJ/144/158 : Prop. of B and Be stars in h and χ Persei (Marsh+, 2012)
J/A+A/560/A16 : Comparison of evolutionary tracks (Martins+, 2013)
J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)
J/AJ/146/102 : Multi-freq. fit of periodic B stars NGC884 (Saesen+, 2013)
J/A+A/580/A23 : Stroemgren-Crawford uvbyβ photometry (Paunzen, 2015)
J/MNRAS/465/2432 : MiMeS magnetic analysis of O-type stars (Grunhut+, 2017)
J/AJ/153/252 : Photo. variability of BeSS-KELT stars (Labadie-Bartz+, 2017)
J/A+A/597/A22 : Massive O- and B-type stars velocities (Simon-Diaz+, 2017)
J/other/AstBu/73.178 : Magnetic fields of CP stars (2011) (Romanyuk+, 2018)
J/AJ/156/102 : The TESS Input Catalog Candidate Target (Stassun+, 2018)
J/ApJS/241/32 : OB stars from the LAMOST DR5 spectra (Liu+, 2019)
http://redcliffcottage.co.za/tess/ : TESS catalog of stars
Byte-by-byte Description of file: table[123].dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Star identifier
17- 25 I09 --- TIC TIC Identifier
27- 33 F7.4 d-1 Freq [2.9/22.2] Primary frequency
35- 38 F4.1 mmag Amp [0.6/44.6] Amplitude
40- 40 A1 --- f_Amp [d] d=Amplitudes may be largely suppressed
42- 43 I2 --- Nm [0/12] Number of modes
45- 46 I2 h RAh Hour of Right Ascension (J2000)
48- 49 I2 min RAm Minute of Right Ascension (J2000)
51- 55 F5.2 s RAs Second of Right Ascension (J2000)
57- 57 A1 --- DE- Sign of the Declination (J2000)
58- 59 I2 deg DEd Degree of Declination (J2000)
61- 62 I2 arcmin DEm Arcminute of Declination (J2000)
64- 67 F4.1 arcsec DEs Arcsecond of Declination (J2000)
69- 73 F5.2 mag Vmag [3.6/12.4] V band magnitude
75- 84 A10 --- SpT Spectral Type
86- 86 A1 --- r_SpT [a-j] Reference flag on SpT; if non
indicated, SpT are from B. Skiff (B/mk) (1)
88- 92 A5 --- Known Known to be a β Cephei star? (2)
94-104 A11 --- Cluster Member of known cluster
106-115 A10 --- f_Name Flag on Star (3)
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Note (1): References as follows:
a = Liu+, 2019, J/ApJS/241/32
b = spectral type corresponds to the temperature reported in
Huang & Gies 2006, J/ApJ/648/580
c = Currie+, 2010, J/ApJS/186/191
d = Stephenson & Sanduleak, 1971PW&SO...1....1S 1971PW&SO...1....1S
e = Renson & Manfroid, 2009, III/260
f = Wright+, 2003, III/231
g = Cannon & Pickering, 1993, III/135
h = Ikhsanov, 1959IzKry..21..229I 1959IzKry..21..229I
i = Houk & Swift, 1999mctd.book.....H 1999mctd.book.....H
j = Nesterov+, 1995, III/182
Note (2): Citations for known ΒCephei as follows:
SH05 = Stankov & Handler 2005, J/ApJS/158/193
H05 = Handler, 2005IBVS.5667....1H 2005IBVS.5667....1H
PP08 = Pigulski & Pojmanski, 2008, J/A+A/477/917
H09 = Huat+, 2009, J/A+A/506/95
JSH09 = Jurcsik+, 2009IBVS.5881....1J 2009IBVS.5881....1J
HM11 = Handler & Meingast, 2011, J/A+A/533/A70
S13 = Saesen+, 2013, J/AJ/146/102
KE02 = Koen & Eyer (2002MNRAS.331...45K 2002MNRAS.331...45K).
Note (3): Flags as follows:
M = discussed in the main paper text
A = commented upon in the Appendix
blend = indicates at there are bright nearby sources contributing flux
in the aperture used by KELT (and likewise with TESS).
nei. = the signal comes from a neighboring star;
sat. = saturation effects cause the signal;
eHe = extreme helium star;
Dsct = δ Scuti pulsation;
SPB = slowly pulsating B star.
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Byte-by-byte Description of file: tableb[123].dat
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Bytes Format Units Label Explanations
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2- 10 I09 --- TIC TIC identifier
12 A1 --- f_TIC [bd] d=Amplitudes may be largely suppressed
14- 22 A9 --- ID Frequency ID (or IDs)
24- 32 F9.6 d-1 Freq [0.005/37.4]? Frequency
34- 41 F8.6 d-1 e_Freq [1e-06/0.0002]? Uncertainty in Freq (1)
43- 47 F5.2 mmag Amp [0.4/46]? Amplitude
49- 52 F4.2 mmag e_Amp [0.06/1]? Uncertainty in Amp (1)
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Note (1): Formal error estimates determined according to
Montgomery & O'Donoghue, 1999DSSN...13...28M 1999DSSN...13...28M
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 12-Oct-2020