J/ApJ/834/207 Periodicity & magnitude of Kepler LCs variation (Mehrabi+, 2017)
Magnetic activity analysis for a sample of G-type main sequence Kepler targets.
Mehrabi A., He H., Khosroshahi H.
<Astrophys. J., 834, 207-207 (2017)>
=2017ApJ...834..207M 2017ApJ...834..207M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, G-type ; Photometry ; Magnetic fields ; Stars, masses ;
Stars, diameters
Keywords: stars: activity; stars: magnetic field; stars: rotation;
stars: solar-type
Abstract:
The variation of a stellar light curve owing to rotational modulation
by magnetic features (starspots and faculae) on the star's surface can
be used to investigate the magnetic properties of the host star. In
this paper, we use the periodicity and magnitude of the light-curve
variation as two proxies to study the stellar magnetic properties for
a large sample of G-type main sequence Kepler targets, for which the
rotation periods were recently determined. By analyzing the
correlation between the two magnetic proxies, it is found that: (1)
the two proxies are positively correlated for most of the stars in our
sample, and the percentages of negative, zero, and positive
correlations are 4.27%, 6.81%, and 88.91%, respectively; (2) negative
correlation stars cannot have a large magnitude of light-curve
variation; and (3) with the increase of rotation period, the relative
number of positive correlation stars decreases and the negative
correlation one increases. These results indicate that stars with
shorter rotation period tend to have positive correlation between the
two proxies, and a good portion of the positive correlation stars have
a larger magnitude of light-curve variation (and hence more intense
magnetic activities) than negative correlation stars.
Description:
The light-curve data of Kepler are divided into 18 quarters (Q0-Q17;
2009-2013). Each quarter (except Q0, Q1, and Q17) contains about three
months of continuous data. We process the light-curve data of each
quarter separately.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 58 4094 The correlation, mean values of iAC, mean value
of Reff, period, mass, radius, and effective
temperature of the Kepler stars
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/AJ/130/873 : Properties of BQS objects in the SDSS DR3 area (Jester+, 2005)
J/AJ/142/112 : KIC photometric calibration (Brown+, 2011)
J/A+A/529/A89 : Kepler satellite variability study (Debosscher+, 2011)
J/AJ/141/50 : White-light flares on cool stars from Kepler (Walkowicz+, 2011)
J/ApJS/199/30 : Effective temperature scale for KIC stars (Pinsonneault+, 2012)
J/other/Nat/485.478 : Superflares on solar-type stars (Maehara+, 2012)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/A+A/557/L10 : Rotation periods of 12000 Kepler stars (Nielsen+, 2013)
J/A+A/560/A4 : Rotation periods of active Kepler stars (Reinhold+, 2013)
J/ApJS/209/5 : Superflares of Kepler stars. I. (Shibayama+, 2013)
J/ApJ/781/124 : Granulation model for 508 KIC stars (Cranmer+, 2014)
J/ApJS/211/2 : Revised properties of Q1-16 Kepler targets (Huber+, 2014)
J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)
J/MNRAS/447/2714 : Flare stars across the H-R diagram (Balona+, 2015)
J/ApJ/829/23 : Stellar flares from Q0-Q17 Kepler LCs (Davenport, 2016)
J/ApJS/229/30 : Revised properties of Q1-17 Kepler targets (Mathur+, 2017)
http://archive.stsci.edu/kepler/ : MAST Kepler access
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC Unique Kepler ID
10- 17 F8.5 --- Cor Correlation between two magnetic proxies
19- 25 F7.5 --- iAC [0.05/0.5] Mean value of degree of periodicity;
see equation 2 (iAC)
27- 33 F7.5 --- Reff [/0.3] Mean value of fluctuation amplitude;
see equation 4 (Reff)
35- 40 F6.3 d Per [4.5/30] The rotation period (1)
42- 47 F6.4 Msun Mass [0.8/1.3] The mass of star (1)
49- 53 F5.3 Rsun Rad [0.6/3.4] The radius of star (2)
55- 58 I4 K Teff [5310/6680] The effective surface temperature (2)
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Note (1): The rotation period and mass values of the stars are taken from the
catalog of McQuillan+ (2014, J/ApJS/211/24).
Note (2): Effective temperature (Teff) and radius are obtained from the Kepler
Input Catalog (KIC) (Brown+ 2011, J/AJ/142/112).
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History:
From electronic version of the journal
(End) Prepared by [ADS], Emmanuelle Perret [CDS] 31-Jul-2017