M-dwarf Eclipsing Binaries with Flare Activity

What is known about the masses of main-sequence stars from the analysis of binary orbits? Double-lined eclipsing binaries are the main source of very precise stellar masses and radii (e.g. Andersen 1997), contributing more than 100 determinations with better than 2% precision over the range 0.6 to 20 Mʘ. For lower-mass stars we are forced to turn to nearby systems with astrometric orbits (e.g. Henry et al. 1993). Not only is the number of good mass determinations from such systems smaller, but also the precision is generally poorer. We are approaching an era when interferometers should have a major impact by supplying good astrometric orbits for dozens of double-lined systems. Already we are beginning to see the sorts of results to expect from this (e.g. Torres et al. 1997). Figure 1. Mass vs. absolute V magnitude for eclipsing binaries (circles) and nearby astrometric binaries (squares) Figure 1 is an updated version of a diagram presented by Henry et al. (1993, their Figure 2). It shows the general run of mass determinations from about 10 Mʘ down to the substellar limit near 0.075 Mʘ. Ninety of the points in Figure 1 are for eclipsing binary masses from Andersen’s review (1991) and are plotted as open circles. The results for eclipsing binaries published since 1991 are plotted as 30 filled circles, adopting the same limit of 2% for the mass precision. In most cases the uncertainties are similar to the size of the symbols. Especially noteworthy is the pair of new points for CM Draconis (Metcalfe et al. 1996) with masses near 0.25 Mʘ. Together with the points for YY Geminorum near 0.6 Mʘ, these are the only M dwarfs that have precise mass determinations. For the most part we are forced to rely on nearby stars with astrometric orbits, to fill in the M dwarf region of the diagram. We have used filled squares in Figure 1 for 29 such systems from Henry et al. (1993), updated using 14 new parallaxes from Hipparcos and 4 from the new Yale Parallax Catalog (1995). Gliese 508 is not included, because it is now known to be a triple, while Gliese 67AB, 570BC, and 623AB are not included because there are not yet any direct measurements of the V magnitude difference for these systems.

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Double-lined M dwarf eclipsing binaries from Catalina Sky Survey and LAMOST

Research in Astronomy and Astrophysics ◽

10.1088/1674-4527/17/2/15 ◽

2017 ◽

Vol 17 (2) ◽

pp. 15 ◽

Cited By ~ 3

Author(s):

Chien-Hsiu Lee ◽

Chien-Cheng Lin

Keyword(s):

Eclipsing Binaries ◽

Sky Survey ◽

M Dwarf

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Low-mass eclipsing binaries in the WFCAM Transit Survey: the persistence of the M-dwarf radius inflation problem

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/sty541 ◽

2018 ◽

Vol 476 (4) ◽

pp. 5253-5267 ◽

Cited By ~ 8

Author(s):

Patricia Cruz ◽

Marcos Diaz ◽

Jayne Birkby ◽

David Barrado ◽

Brigitta Sipöcz ◽

...

Keyword(s):

Eclipsing Binaries ◽

Low Mass ◽

M Dwarf

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Stability of planetary, single M dwarf, and binary star companions to Kepler detached eclipsing binaries and a possible five-body system

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2532 ◽

2020 ◽

Vol 498 (3) ◽

pp. 4356-4364

Author(s):

A K Getley ◽

B Carter ◽

R King ◽

S O’Toole

Keyword(s):

Binary Stars ◽

Binary Star ◽

Eclipsing Binaries ◽

Body System ◽

Star System ◽

Flip Flop ◽

Eclipsing Binary ◽

Photometric Monitoring ◽

Eclipsing Binary Star ◽

M Dwarf

ABSTRACT In this study, we identify 11 Kepler systems (KIC 5255552, 5653126, 5731312, 7670617, 7821010, 8023317, 10268809, 10296163, 11519226, 11558882, and 12356914) with a flip-flop effect in the eclipse timing variations O − C diagrams of the systems, report on what these systems have in common and whether these systems are dynamically stable. These systems have previously reported high eccentric binary stars with highly eccentric third bodies/outer companions. We find that all of the additional bodies in the system are dynamically stable for the configurations previously reported and are therefore likely to exist as described. We also provide additional evidence of KIC 5255552 being a quadruple star system composed of an eclipsing binary pair and non-eclipsing binary pair with the possibility of a fifth body in the system. With the advent of the NASA’s Transiting Exoplanet Survey Satellite (TESS) exoplanet survey, its precision photometric monitoring offers an opportunity to help confirm more local eclipsing binary star companions, including planets.

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HST/FGS Trigonometric Parallaxes of M-dwarf Eclipsing Binaries

Publications of the Astronomical Society of the Pacific ◽

10.1088/1538-3873/ab7b91 ◽

2020 ◽

Vol 132 (1011) ◽

pp. 054201

Author(s):

Gerard T. van Belle ◽

Gail H. Schaefer ◽

Kaspar von Braun ◽

Edmund P. Nelan ◽

Zachary Hartman ◽

...

Keyword(s):

Eclipsing Binaries ◽

Trigonometric Parallaxes ◽

M Dwarf

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EDEN: Flare Activity of the Nearby Exoplanet-hosting M Dwarf Wolf 359 Based on K2 and EDEN Light Curves

The Astronomical Journal ◽

10.3847/1538-3881/abf933 ◽

2021 ◽

Vol 162 (1) ◽

pp. 11

Author(s):

Chia-Lung Lin ◽

Wen-Ping Chen ◽

Wing-Huen Ip ◽

Dániel Apai ◽

Alex Bixel ◽

...

Keyword(s):

Light Curves ◽

Flare Activity ◽

M Dwarf

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Eclipsing Binaries: Precise Clocks to Detect Extrasolar Planets

Proceedings of the International Astronomical Union ◽

10.1017/s174392131301274x ◽

2012 ◽

Vol 8 (S293) ◽

pp. 165-167

Author(s):

Emil Kundra ◽

Theodor Pribulla ◽

Martin Vaňko ◽

Ľubomír Hambálek

Keyword(s):

White Dwarf ◽

Extrasolar Planets ◽

Ccd Camera ◽

Eclipsing Binaries ◽

List Type ◽

Object Selection ◽

Low Mass ◽

Selection For ◽

Orbital Periods ◽

M Dwarf

AbstractProject Dwarf is a new observing campaign focused on the detection of substellar companions to low-mass (composed of late-type, subdwarf (sd) or/and white dwarf (WD) components) detached eclipsing binaries using minima timing. The crucial condition for the object selection for this campaign is possibility to determine times of the minima with high precision. This is naturally fullfilled for eclipsing binaries with deep and narrow minima or systems hosting a WD component showing fast ingress or egress.The observing project includes three groups of close eclipsing binaries indicating presence of substellar circum-binary components: (i)systems with K or/and M dwarf components(ii)systems with hot subdwarf (sd) and M dwarf components(iii)systems with white dwarf (WD) component(s). The sample of the eclipsing systems have orbital periods in range of 0.1 to almost 3 days and their brightness fits possibilities of small telescopes equipped with a low-end CCD camera and at least VRI filter set. Such kind of telescopes allow us to develop observing network including also amateur astronomers.

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High-resolution spectroscopy of flares and CMEs on AD Leonis

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936904 ◽

2020 ◽

Vol 637 ◽

pp. A13 ◽

Cited By ~ 4

Author(s):

P. Muheki ◽

E. W. Guenther ◽

T. Mutabazi ◽

E. Jurua

Keyword(s):

High Resolution ◽

Spectral Lines ◽

High Resolution Spectroscopy ◽

Flare Activity ◽

The Sun ◽

M Dwarfs ◽

Highly Active ◽

M Stars ◽

High Level ◽

M Dwarf

Context. Flares and coronal mass ejections (CMEs) are important for the evolution of the atmospheres of planets and their potential habitability, particularly for planets orbiting M stars at a distance <0.4 AU. Detections of CMEs on these stars have been sparse, and previous studies have therefore modelled their occurrence frequency by scaling up solar relations. However, because the topology and strength of the magnetic fields on M stars is different from that of the Sun, it is not obvious that this approach works well. Aims. We used a large number of high-resolution spectra to study flares, CMEs, and their dynamics of the active M dwarf star AD Leo. The results can then be used as reference for other M dwarfs. Methods. We obtained more than 2000 high-resolution spectra (R ~ 35 000) of the highly active M dwarf AD Leo, which is viewed nearly pole on. Using these data, we studied the behaviour of the spectral lines Hα, Hβ, and He I 5876 in detail and investigated asymmetric features that might be Doppler signatures of CMEs. Results. We detected numerous flares. The largest flare emitted 8.32 × 1031 erg in Hβ and 2.12 × 1032 erg in Hα. Although the spectral lines in this and other events showed a significant blue asymmetry, the velocities associated with it are far below the escape velocity. Conclusions. Although AD Leo shows a high level of flare activity, the number of CMEs is relatively low. It is thus not appropriate to use the same flare-to-CME relation for M dwarfs as for the Sun.

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NGTS and WASP photometric recovery of a single-transit candidate from TESS

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3212 ◽

2019 ◽

Cited By ~ 6

Author(s):

Samuel Gill ◽

Daniel Bayliss ◽

Benjamin F Cooke ◽

Peter J Wheatley ◽

Louise D Nielsen ◽

...

Keyword(s):

Radial Velocity ◽

Stellar Evolution ◽

Orbital Period ◽

Eclipsing Binaries ◽

Dwarf Star ◽

Velocity Measurements ◽

Eclipsing Binary ◽

Long Period ◽

M Dwarf

Abstract The Transiting Exoplanet Survey Satellite (TESS) produces a large number of single-transit event candidates, since the mission monitors most stars for only ∼27 days. Such candidates correspond to long-period planets or eclipsing binaries. Using the TESS Sector 1 full-frame images, we identified a 7750 ppm single-transit event with a duration of 7 hours around the moderately evolved F-dwarf star TIC-238855958 (Tmag=10.23, Teff=6280±85 K). Using archival WASP photometry we constrained the true orbital period to one of three possible values. We detected a subsequent transit-event with NGTS, which revealed the orbital period to be 38.20 d. Radial velocity measurements from the CORALIE Spectrograph show the secondary object has a mass of M2= 0.148 ± 0.003 M⊙, indicating this system is an F-M eclipsing binary. The radius of the M-dwarf companion is R2 = 0.171 ± 0.003 R⊙, making this one of the most well characterised stars in this mass regime. We find that its radius is 2.3-σ lower than expected from stellar evolution models.

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