A super-Earth and a sub-Neptune orbiting the bright, quiet M3 dwarf TOI-1266

We report the discovery and characterisation of a super-Earth and a sub-Neptune transiting the bright (K = 8.8), quiet, and nearby (37 pc) M3V dwarf TOI-1266. We validate the planetary nature of TOI-1266 b and c using four sectors of TESS photometry and data from the newly-commissioned 1-m SAINT-EX telescope located in San Pedro Mártir (México). We also include additional ground-based follow-up photometry as well as high-resolution spectroscopy and high-angular imaging observations. The inner, larger planet has a radius of R = 2.37−0.12+0.16 R⊕ and an orbital period of 10.9 days. The outer, smaller planet has a radius of R = 1.56−0.13+0.15 R⊕ on an 18.8-day orbit. The data are found to be consistent with circular, co-planar and stable orbits that are weakly influenced by the 2:1 mean motion resonance. Our TTV analysis of the combined dataset enables model-independent constraints on the masses and eccentricities of the planets. We find planetary masses of Mp = 13.5−9.0+11.0 M⊕ (<36.8 M⊕ at 2-σ) for TOI-1266 b and 2.2−1.5+2.0 M⊕ (<5.7 M⊕ at 2-σ) for TOI-1266 c. We find small but non-zero orbital eccentricities of 0.09−0.05+0.06 (<0.21 at 2-σ) for TOI-1266 b and 0.04 ± 0.03 (< 0.10 at 2-σ) for TOI-1266 c. The equilibrium temperatures of both planets are of 413 ± 20 and 344 ± 16 K, respectively, assuming a null Bond albedo and uniform heat redistribution from the day-side to the night-side hemisphere. The host brightness and negligible activity combined with the planetary system architecture and favourable planet-to-star radii ratios makes TOI-1266 an exquisite system for a detailed characterisation.

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TOI-150b and TOI-163b: two transiting hot Jupiters, one eccentric and one inflated, revealed by TESS near and at the edge of the JWST CVZ

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2433 ◽

2019 ◽

Vol 490 (1) ◽

pp. 1094-1110 ◽

Cited By ~ 3

Author(s):

Diana Kossakowski ◽

Néstor Espinoza ◽

Rafael Brahm ◽

Andrés Jordán ◽

Thomas Henning ◽

...

Keyword(s):

High Resolution ◽

Time Scale ◽

High Resolution Spectroscopy ◽

Spin Orbit ◽

Eccentric Orbit ◽

Hot Jupiters ◽

Eclipse Observations ◽

James Webb Space Telescope ◽

Hot Jupiter

Abstract We present the discovery of TYC9191-519-1b (TOI-150b, TIC 271893367) and HD271181b (TOI-163b, TIC 179317684), two hot Jupiters initially detected using 30-min cadence Transiting Exoplanet Survey Satellite (TESS) photometry from Sector 1 and thoroughly characterized through follow-up photometry (CHAT, Hazelwood, LCO/CTIO, El Sauce, TRAPPIST-S), high-resolution spectroscopy (FEROS, CORALIE), and speckle imaging (Gemini/DSSI), confirming the planetary nature of the two signals. A simultaneous joint fit of photometry and radial velocity using a new fitting package juliet reveals that TOI-150b is a $1.254\pm 0.016\ \rm {R}_ \rm{J}$, massive ($2.61^{+0.19}_{-0.12}\ \rm {M}_ \rm{J}$) hot Jupiter in a 5.857-d orbit, while TOI-163b is an inflated ($R_ \rm{P}$ = $1.478^{+0.022}_{-0.029} \,\mathrm{ R}_ \rm{J}$, $M_ \rm{P}$ = $1.219\pm 0.11 \, \rm{M}_ \rm{J}$) hot Jupiter on a P = 4.231-d orbit; both planets orbit F-type stars. A particularly interesting result is that TOI-150b shows an eccentric orbit ($e=0.262^{+0.045}_{-0.037}$), which is quite uncommon among hot Jupiters. We estimate that this is consistent, however, with the circularization time-scale, which is slightly larger than the age of the system. These two hot Jupiters are both prime candidates for further characterization – in particular, both are excellent candidates for determining spin-orbit alignments via the Rossiter–McLaughlin (RM) effect and for characterizing atmospheric thermal structures using secondary eclipse observations considering they are both located closely to the James Webb Space Telescope (JWST) Continuous Viewing Zone (CVZ).

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K2-19, The first K2 muti-planetary system showing TTVs

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316002386 ◽

2015 ◽

Vol 11 (A29A) ◽

pp. 51-56

Author(s):

S. C. C. Barros ◽

J. M. Almenara ◽

O. Demangeon ◽

M. Tsantaki ◽

A. Santerne ◽

...

Keyword(s):

System Architecture ◽

Planetary System ◽

Light Curves ◽

Dynamical Model ◽

Dynamic Simulations ◽

Short Period ◽

Resonant Systems ◽

The Individual ◽

The Masses ◽

Body Dynamic

AbstractIn traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.

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Radial velocity follow-up for confirmation and characterization of transiting exoplanets

Proceedings of the International Astronomical Union ◽

10.1017/s174392130802632x ◽

2008 ◽

Vol 4 (S253) ◽

pp. 129-139 ◽

Cited By ~ 11

Author(s):

François Bouchy ◽

Claire Moutou ◽

Didier Queloz ◽

Keyword(s):

High Resolution ◽

Radial Velocity ◽

Space Mission ◽

High Resolution Spectroscopy

AbstractRadial Velocity follow-up is essential to establish or exclude the planetary nature of a transiting companion as well as to accurately determine its mass. Here we present some elements of an efficient Doppler follow-up strategy, based on high-resolution spectroscopy, devoted to the characterization of transiting candidates. Some aspects and results of the radial velocity follow-up of the CoRoT space mission are presented in order to illustrate the strategy used to deal with the zoo of transiting candidates.

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K2-141 b

Astronomy and Astrophysics ◽

10.1051/0004-6361/201732217 ◽

2018 ◽

Vol 612 ◽

pp. A95 ◽

Cited By ~ 22

Author(s):

O. Barragán ◽

D. Gandolfi ◽

F. Dai ◽

J. Livingston ◽

C. M. Persson ◽

...

Keyword(s):

High Resolution ◽

Radial Velocity ◽

High Precision ◽

Orbital Period ◽

Total Mass ◽

Iron Composition ◽

Short Period

We report on the discovery of K2-141 b (EPIC 246393474 b), an ultra-short-period super-Earth on a 6.7 h orbit transiting an active K7 V star based on data from K2 campaign 12. We confirmed the planet’s existence and measured its mass with a series of follow-up observations: seeing-limited MuSCAT imaging, NESSI high-resolution speckle observations, and FIES and HARPS high-precision radial-velocity monitoring. K2-141 b has a mass of 5.31 ± 0.46 M⊕ and radius of 1.54−0.09+0.10 R⊕, yielding a mean density of 8.00−1.45+1.83 g cm−3 and suggesting a rocky-iron composition. Models indicate that iron cannot exceed ~70% of the total mass. With an orbital period of only 6.7 h, K2-141 b is the shortest-period planet known to date with a precisely determined mass.

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Hidden in Plain Sight: A double-lined White Dwarf Binary 26 pc away and a Distant Cousin

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab439 ◽

2021 ◽

Author(s):

Mukremin Kilic ◽

A Bédard ◽

P Bergeron

Keyword(s):

High Resolution ◽

Orbital Period ◽

White Dwarf ◽

White Dwarfs ◽

Model Atmosphere ◽

High Resolution Spectroscopy ◽

Low Mass ◽

Orbital Periods ◽

Velocity Changes ◽

Cool White Dwarfs

Abstract We present high-resolution spectroscopy of two nearby white dwarfs with inconsistent spectroscopic and parallax distances. The first one, PG 1632+177, is a 13th magnitude white dwarf only 25.6 pc away. Previous spectroscopic observations failed to detect any radial velocity changes in this star. Here, we show that PG 1632+177 is a 2.05 d period double-lined spectroscopic binary (SB2) containing a low-mass He-core white dwarf with a more-massive, likely CO-core white dwarf companion. After L 870-2, PG 1632+177 becomes the second closest SB2 white dwarf currently known. Our second target, WD 1534+503, is also an SB2 system with an orbital period of 0.71 d. For each system, we constrain the atmospheric parameters of both components through a composite model-atmosphere analysis. We also present a new set of NLTE synthetic spectra appropriate for modeling high-resolution observations of cool white dwarfs, and show that NLTE effects in the core of the Hα line increase with decreasing effective temperature. We discuss the orbital period and mass distribution of SB2 and eclipsing double white dwarfs with orbital constraints, and demonstrate that the observed population is consistent with the predicted period distribution from the binary population synthesis models. The latter predict more massive CO + CO white dwarf binaries at short (<1 d) periods, as well as binaries with several day orbital periods; such systems are still waiting to be discovered in large numbers.

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The SPEKTROSAT Mission

International Astronomical Union Colloquium ◽

10.1017/s0252921100012495 ◽

1990 ◽

Vol 115 ◽

pp. 295-301

Author(s):

Peter Predehl

Keyword(s):

High Resolution ◽

Field Of View ◽

High Resolution Spectroscopy ◽

Third Order ◽

X Ray ◽

Transmission Grating ◽

Important Diagnostic Tool ◽

Low Costs ◽

Better Than

AbstractHigh resolution spectroscopy will be an important diagnostic tool in future X-ray astronomy. SPEKTROSAT, the follow-up mission to ROSAT will be equipped with a transmission grating spectrometer with a spectral resolution of 0.2 Å over the wavelength range between 6 Å and 300 Å. Third order aberations are minimized by a mounting of the grating elements according to the Rowland-torus geometry. The ROSAT mirror system will be slightly changed by a redesign of the optical stops in order to reduce the field of view. The Focal Instrumentation has to be modified for a better match with the spectroscopic requirements. Since SPEKTROSAT is almost identical to ROSAT, this concept offers a large amount of science at relatively low costs. Its limiting line sensitivity will be about 20 times better than that of the EINSTEIN-OGS.

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The Hamburg/ESO Survey for Bright QSOs — Slitless Spectroscopy at High Resolution

Symposium - International Astronomical Union ◽

10.1017/s0074180900048427 ◽

1994 ◽

Vol 161 ◽

pp. 723-727 ◽

Cited By ~ 1

Author(s):

L. Wisotzki

Keyword(s):

High Resolution ◽

High Redshift ◽

Gravitational Lens ◽

High Resolution Spectroscopy ◽

Wide Angle ◽

X Rays ◽

Digital Revolution ◽

First Results ◽

Objective Prism

The digital revolution in the evaluation of photographic plates and the introduction of automated quasar search techniques have drastically increased the number of known QSOs over the past decade. However, most of these QSOs are so faint that their use is limited to statistical studies. The bright end of the quasar population is still dominated by objects selected in other wavebands, such as radio, X-rays, or even infrared. We have started in 1990 a wide-angle objective-prism survey (the Hamburg/ESO Survey, HES) using the 1 m ESO Schmidt telescope (Reimers 1990). The survey is intended to cover 5000 deg2, of which about a third has been acquired up to now. The prime goal is to compile a large sample of bright (B < 17.5) QSOs suited for detailed follow-up studies, in particular for high-resolution spectroscopy. Other objectives are to search for gravitational lens candidates and to directly measure the local luminosity function of quasars. In each Schmidt field, a spectral and a direct plate are scanned with the PDS 1010G microdensitometer at Hamburg, followed by an automated candidate selection and subsequent follow-up spectroscopy with the ESO 1.52 m and 3.6 m telescopes. A novel feature in our survey is the use of an objective-prism with a dispersion of 450 å/mm at Hγ, yielding a seeing-limited spectral resolution of 10–20 å FWHM. A full documentation of the survey techniques is in preparation. First results include the discoveries of the second-brightest QSO in the south (Wisotzki et al. 1991), and of a bright double QSO at high redshift, probably a gravitational lens (Wisotzki et al. 1993). In this contribution I want to show how a wide-angle quasar survey like the HES can benefit from the high resolution of the survey spectra.

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SOPHIE velocimetry of Kepler transit candidates

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834333 ◽

2019 ◽

Vol 623 ◽

pp. A104 ◽

Cited By ~ 1

Author(s):

G. Hébrard ◽

A. S. Bonomo ◽

R. F. Díaz ◽

A. Santerne ◽

N. C. Santos ◽

...

Keyword(s):

Radial Velocity ◽

Orbital Period ◽

Planetary System ◽

Giant Planet ◽

Eccentric Orbit ◽

Promising Candidate ◽

Single Star ◽

Orbital Periods ◽

Host Stars

Whereas thousands of transiting giant exoplanets are known today, only a few are well characterized with long orbital periods. Here we present KOI-3680b, a new planet in this category. First identified by the Kepler team as a promising candidate from the photometry of the Kepler spacecraft, we establish here its planetary nature from the radial velocity follow-up secured over 2 yr with the SOPHIE spectrograph at Observatoire de Haute-Provence, France. The combined analysis of the whole dataset allows us to fully characterize this new planetary system. KOI-3680b has an orbital period of 141.2417 ± 0.0001 days, a mass of 1.93 ± 0.20 MJup, and a radius of 0.99 ± 0.07 RJup. It exhibits a highly eccentric orbit (e = 0.50 ± 0.03) around an early G dwarf. KOI-3680b is the transiting giant planet with the longest period characterized so far around a single star; it offers opportunities to extend studies which were mainly devoted to exoplanets close to their host stars, and to compare both exoplanet populations.

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The TOI-763 system: sub-Neptunes orbiting a Sun-like star

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2502 ◽

2020 ◽

Vol 498 (3) ◽

pp. 4503-4517

Author(s):

M Fridlund ◽

J Livingston ◽

D Gandolfi ◽

C M Persson ◽

K W F Lam ◽

...

Keyword(s):

Light Curve ◽

Orbital Period ◽

Planetary System ◽

Space Mission ◽

The Sun ◽

Minimum Mass ◽

Dwarf Star ◽

Stellar Spectrum ◽

Transit Signals

ABSTRACT We report the discovery of a planetary system orbiting TOI-763(aka CD-39 7945), a V = 10.2, high proper motion G-type dwarf star that was photometrically monitored by the TESS space mission in Sector 10. We obtain and model the stellar spectrum and find an object slightly smaller than the Sun, and somewhat older, but with a similar metallicity. Two planet candidates were found in the light curve to be transiting the star. Combining TESS transit photometry with HARPS high-precision radial velocity (RV) follow-up measurements confirm the planetary nature of these transit signals. We determine masses, radii, and bulk densities of these two planets. A third planet candidate was discovered serendipitously in the RV data. The inner transiting planet, TOI-763 b, has an orbital period of Pb = 5.6 d, a mass of Mb = 9.8 ± 0.8 M⊕, and a radius of Rb = 2.37 ± 0.10 R⊕. The second transiting planet, TOI-763 c, has an orbital period of Pc = 12.3 d, a mass of Mc = 9.3 ± 1.0 M⊕, and a radius of Rc = 2.87 ± 0.11 R⊕. We find the outermost planet candidate to orbit the star with a period of ∼48 d. If confirmed as a planet, it would have a minimum mass of Md = 9.5 ± 1.6 M⊕. We investigated the TESS light curve in order to search for a mono transit by planet d without success. We discuss the importance and implications of this planetary system in terms of the geometrical arrangements of planets orbiting G-type stars.

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