J/AJ/158/177 Near-resonance in a system of sub-Neptunes from TESS (Quinn+, 2019)
Near-resonance in a system of sub-Neptunes from TESS.
Quinn S.N., Becker J.C., Rodriguez J.E., Hadden S., Huang C.X.,
Morton T.D., Adams F.C., Armstrong D., Eastman J.D., Horner J., Kane S.R.,
Lissauer J.J., Twicken J.D., Vanderburg A., Wittenmyer R., Ricker G.R.,
Vanderspek R.K., Latham D.W., Seager S., Winn J.N., Jenkins J.M., Agol E.,
Barkaoui K., Beichman C.A., Bouchy F., Bouma L.G., Burdanov A.,
Campbell J., Carlino R., Cartwright S.M., Charbonneau D.,
Christiansen J.L., Ciardi D., Collins K.A., Collins K.I., Conti D.M.,
Crossfield I.J.M., Daylan T., Dittmann J., Doty J., Dragomir D., Ducrot E.,
Gillon M., Glidden A., Goeke R.F., Gonzales E.J., Helminiak K.G.,
Horch E.P., Howell S.B., Jehin E., Jensen E.L.N., Kielkopf J.F.,
Kristiansen M.H., Law N., Mann A.W., Marmier M., Matson R.A., Matthews E.,
Mazeh T., Mori M., Murgas F., Murray C., Narita N., Nielsen L.D.,
Ottoni G., Palle E., Pawlaszek R., Pepe F., de Leon J.P., Pozuelos F.J.,
Relles H.M., Schlieder J.E., Sebastian D., Segransan D., Shporer A.,
Stassun K.G., Tamura M., Udry S., Waite I., Winters J.G., Ziegler C.
<Astron. J., 158, 177-177 (2019)>
=2019AJ....158..177Q 2019AJ....158..177Q (SIMBAD/NED BibCode)
ADC_Keywords: Exoplanets ; Models
Keywords: Transit photometry - Mini Neptunes - Super Earths - Exoplanets
Abstract:
We report the Transiting Exoplanet Survey Satellite detection of a
multi-planet system orbiting the V=10.9 K0 dwarf TOI-125. We find
evidence for up to five planets, with varying confidence. Three transit
signals with high signal-to-noise ratio correspond to sub-Neptune-sized
planets (2.76, 2.79, and 2.94 R⊕), and we statistically validate
the planetary nature of the two inner planets (Pb=4.65 days,
Pc=9.15 days). With only two transits observed, we report the outer
object (P.03=19.98 days) as a planet candidate with high signal-to-noise
ratio. We also detect a candidate transiting super-Earth (1.4 R⊕)
with an orbital period of only 12.7 hr and a candidate Neptune-sized planet
(4.2 R⊕) with a period of 13.28 days, both at low signal-to-noise
ratio. This system is amenable to mass determination via radial velocities
and transit-timing variations, and provides an opportunity to study planets
of similar size while controlling for age and environment. The ratio of
orbital periods between TOI-125 b and c (Pc/Pb=1.97) is slightly lower
than an exact 2:1 commensurability and is atypical of multiple planet
systems from Kepler, which show a preference for period ratios just wide
of first-order period ratios. A dynamical analysis refines the allowed
parameter space through stability arguments and suggests that despite
the nearly commensurate periods, the system is unlikely to be in resonance.
Description:
To evaluate the dynamical stability and orbital evolution of the three
planets in the TOI-125 system, we performed 3000 numerical simulations
using the N-body code Mercury6 (Chambers 1999MNRAS.304..793C 1999MNRAS.304..793C), altered
to include the effect of general relativistic precession. The simulations
were performed using a hybrid symplectic and Bulirsch-Stoer (B-S)
integrator with a time-step of 30 minutes for a total integration time
of slightly more than 1 million years per integration (which is roughly
80 million orbits of the innermost planet), and energy was conserved
to better than one part in 109 (for energy changes due to the integrator).
For each integration, we drew one link from the EXOFASTv2 transit fit
posterior, and assigned planet and star properties equal to those in
the chosen posterior link.
Objects:
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RA (ICRS) DE Designation(s)
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01 34 22.73 -66 40 33.0 TOI 125 = TYC 8856-192-1
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig9.dat 115 8990 Results of simulation used to create Figure 9
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See also:
J/ApJ/809/77 : Transiting Exoplanet Survey Satellite (TESS) (Sullivan+, 2015)
J/AJ/156/102 : The TESS Input Catalog and Candidate Target List
(Stassun+, 2018)
J/ApJS/239/2 : Simulated exoplanets from TESS list of targets (Barclay+, 2018)
Byte-by-byte Description of file: fig9.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- N [0/8989] Row index
6- 44 A39 --- Res Resonant behavior
46- 49 I4 --- Trial [4501/7867] Trial number
51- 53 A3 --- Stab [yes no] Whole system stable?
55- 69 F15.7 yr End [2.1548928/1000614.648] End time of simulation
71- 78 F8.6 AU a [0.049433/0.14511] Initial semi-major axis
80- 87 F8.6 --- e [7.1e-05/0.502095] Initial orbital eccentricity
89- 95 F7.4 deg i [87.5434/89.9991] Initial orbital inclination
97-104 E8.2 --- Mp/M* [1.1e-05/0.000102] Planet-star mass ratio
106-113 F8.4 deg peri [0.0416/359.746] Initial longitude of periastron
115 I1 --- pl [0/2] Planet number
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 16-Dec-2019