J/ApJ/728/48 Multicolor eclipse data for 6 new binaries (Kraus+, 2011)
The Mass-Radius(-Rotation?) relation for low-mass stars.
Kraus A.L., Tucker R.A., Thompson M.I., Craine E.R., Hillenbrand L.A.
<Astrophys. J., 728, 48 (2011)>
=2011ApJ...728...48K 2011ApJ...728...48K
ADC_Keywords: Binaries, eclipsing ; Stars, M-type ; Stars, masses ;
Photometry, VRI
Keywords: binaries: eclipsing - stars: fundamental parameters -
stars: late-type - stars: low-mass - stars: rotation
Abstract:
We present the discovery and characterization of six new M dwarf
eclipsing binary systems. The 12 stars in these eclipsing systems have
masses spanning 0.38-0.59M☉ and orbital periods of 0.6-1.7 days,
with typical uncertainties of ∼0.3% in mass and ∼0.5%-2.0% in radius.
Combined with six known systems with high-precision measurements, our
results reveal an intriguing trend in the low-mass regime. For stars
with M=0.35-0.80M☉, components in short-period binary systems
(P≲1 day; 12 stars) have radii which are inflated by up to 10%
(µ=4.8±1.0%) with respect to evolutionary models for low-mass
main-sequence stars, whereas components in longer-period systems (>1.5
days; 12 stars) tend to have smaller radii (µ=1.7±0.7%).
Description:
All six systems were identified in the variability catalog of the
First MOTESS-GNAT variable star survey (MG1; Kraus et al. 2007,
Cat. J/AJ/134/1488). MG1 is a deep, wide-field imaging survey which
was conducted with the Moving Object and Transient Event Search System
(MOTESS).
We obtained low-resolution optical spectra of the candidates selected
in MG1 to distinguish true M dwarfs from reddened early-type stars,
yielding ∼30 M dwarfs which were likely EBs. All of our spectra were
obtained with the Double Spectrograph on the Hale 5m telescope at
Palomar Observatory. Spectra presented here were obtained with a
spectral resolution of R∼1250 over a wavelength range of 6400-8800Å.
Finally, we performed intensive photometric monitoring of each system
with small telescopes to confirm its eclipsing nature and establish
its period.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 112 6 New M-dwarf eclipsing binaries
table4.dat 34 2833 Multicolor eclipse data
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See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2012)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
I/284 : The USNO-B1.0 Catalog (Monet+ 2003)
J/A+A/526/A29 : ASAS low-mass EB* light curves (Helminiak+, 2011)
J/AJ/141/78 : Low-mass eclipsing binaries in KIC (Coughlin+, 2011)
J/ApJ/684/635 : New low-mass eclipsing binary from SDSS-II (Blake+, 2008)
J/AJ/134/2340 : Membership of Praesepe and Coma Berenices (Kraus+, 2007)
J/AJ/134/1488 : MG1 Variable Star Catalog (MG1-VSC) (Kraus+, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [MG1-]
5- 11 I7 --- MG1 Source name (G1)
13- 14 I2 h RAh Hour of right ascension (J2000)
16- 17 I2 min RAm Minute of right ascension (J2000)
19- 22 F4.1 s RAs Second of right ascension (J2000)
24 A1 --- DE- [+] Sign of declination (J2000)
25- 26 I2 deg DEd [3] Degree of declination (J2000)
28- 29 I2 arcmin DEm Arcminute of declination (J2000)
31- 32 I2 arcsec DEs Arcsecond of declination (J2000)
34- 37 F4.1 mag Rmag MG1 R-band magnitude (1)
39- 43 F5.2 mag Ksmag [11.6/13.3] 2MASS Ks-band magnitude (with
uncertainties of ∼0.2mag)
45- 49 F5.2 mag mbol Bolometric magnitude (with uncertainties of
∼0.05mag) (2)
51- 53 I3 mas/yr pmRA Proper motion along RA (µRA) (2)
55- 57 I3 mas/yr pmDE Proper motion along DE (µDE) (2)
59 I1 mas/yr e_pm Uncertainty along each axis (2)
61- 64 A4 --- SpT MK best-fit spectral type (2)
66- 68 F3.1 --- e_SpT Spectral type uncertainty (2)
70- 78 F9.7 d Per [0.6/1.8] Orbital period (from table 8)
80- 88 F9.7 d e_Per Per uncertainty (from table 8)
90- 94 F5.3 Msun M1 Mass of A component (from table 8)
96-100 F5.3 Msun e_M1 M1 uncertainty (from table 8)
102-106 F5.3 Msun M2 Mass of B component (from table 8)
108-112 F5.3 Msun e_M2 M2 uncertainty (from table 8)
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Note (1): The photometric uncertainties are ∼0.1-0.2mag for MG1 R and are
systematic since it is calibrated into the less well-defined USNOB1.0
R magnitude system.
Note (2): The derived properties (mbol, µ, and SpT) were calculated using
the multi-catalog data mining procedure we described in Kraus &
Hillenbrand (2007, Cat. J/AJ/134/2340).
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 I7 --- MG1 Source name (G1)
9 A1 --- Filt [IRV] Filter used (I, R or V)
11- 21 F11.6 d HJD [4547.6/4783.9] Heliocentric Julian Date
(HJD-2450000)
23- 28 F6.3 mag Dmag Differential magnitude in Filt (1)
30- 34 F5.3 mag e_Dmag Photometric uncertainty in Delmag (2)
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Note (1): With respect to the average of all measurements taken outside of the
eclipse, such that the magnitude outside of eclipse is M=0.
Note (2): Corresponding to the photon counting statistics for the source and
background. In our light curve fits, we replaced this measurement
with the observed scatter outside of eclipse (Table 3) if the
observed scatter was larger, indicating that other noise sources
dominated.
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Global notes:
Note (G1): From MG1 variable star catalog; Kraus et al. 2007,
Cat. J/AJ/134/1488, <MOTESS-GNAT NNNNNNN> in Simbad.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 04-Sep-2012