Five transiting hot Jupiters discovered using WASP-South,Euler, and TRAPPIST: WASP-119 b, WASP-124 b, WASP-126 b, WASP-129 b, and WASP-133 b

Abstract

We have used photometry from the WASP-South instrument to identify 5 stars showing planet-like transits in their light curves. The planetary nature of the companions to these stars has been confirmed using photometry from the EulerCam instrument on the Swiss Euler 1.2-m telescope and the TRAPPIST telescope, and spectroscopy obtained with the CORALIE spectrograph. The planets discovered are hot Jupiter systems with orbital periods in the range 2.17 to 5.75 days, masses from 0.3 M Jup to 1.2 M Jup and with radii from 1 R Jup to 1.5 R Jup . These planets orbit bright stars (V = 11-13) with spectral types in the range F9 to G4. WASP-126 is the brightest planetary system in this sample and hosts a low-mass planet with a large radius (0.3 M Jup , 0.95 R Jup ), making it a good target for transmission spectroscopy. The high density of WASP-129 A suggests that it is a helium-rich star similar to HAT-P-11 A. WASP-133 A has an enhanced surface lithium abundance compared to other old G-type stars, particularly other planet host stars. These planetary systems are good targets for follow-up observations with ground-based and space-based facilities to study their atmospheric and dynamical properties. Key words. planetary systems IntroductionGround-based transit surveys such as WASP (Pollacco et al. 2008), HAT (Bakos et al. 2004), HAT-South (Bakos et al. 2013) and KELT (Pepper et al. 2008) have identified the majority of bright hot Jupiter planetary systems that have been studied in detail using observations with large ground-based telescopes and space-based instrumentation. Although space-based surveys such as Kepler-K2 (Howell et al. 2014), TESS (Ricker et al. 2015 and PLATO (Rauer et al. 2014) will produce much higher quality photometry than is possible from the ground, it is advantageous to identify as many planetary systems as possible in the areas of the sky that will be observed by these missions so that the observing strategy can be optimised. This was clearly demonstrated by the recent discovery that WASP-47 is a very rare example of a multiple-planet system containing a hot Jupiter (Becker et al. 2015;Neveu-VanMalle et al. 2016). This discovery was only possible because this known Full Tables 2 and 3 are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/591/A55 planetary system was prioritised for high-cadence observations with Kepler-K2. These high-cadence observations made it possible to detect the transit time variations produced by the gravitational interactions between the planets in this system. The discovery that WASP-47 is a multi-planet system also demonstrates that detailed obervations of apparently normal hot Jupiter systems continue to reveal unexpected properties of this diverse group of planetary systems.Here we present the discovery of 5 hot-Jupiter planetary systems in the southern hemisphere. Section 2 describes the observations we have obtained, Sect. 3 describes our analysis of the host stars, the stella...

eleanor: An Open-source Tool for Extracting Light Curves from the TESS Full-frame Images

“…We use the batman (Kreidberg 2015) transit fitting software package, following the methods from Mandel & Agol (2002), to derive planet parameters from the eleanor light curves and compare our results with the known parameters. The planet parameters we derived are consistent with values quoted in Maxted et al (2016) and Stassun et al (2017) for the WASP planets, and with Huang et al (2018) and Gandolfi et al (2018) We complete a more extensive Markov Chain Monte Carlo (MCMC) analysis for WASP-126b (Maxted et al 2016) using emcee (Foreman-Mackey et al 2013), an implementation of the affine-invariant ensemble sampler of Goodman & Weare (2010). We initialized our MCMC run with the best-fit parameters from a single batman fit and ran it for 200 steps, to complete a burn-in.…”

A Search for Multiplanet Systems with TESS Using a Bayesian N-body Retrieval and Machine Learning

“…The inclination value of the transiting planet is adopted from the phase folded light curve fit while the inclination of the perturbing planet is fixed to 90 degrees. The eccentricity of two transiting planets, WASP-18 b and WASP-126 b, are both set to 0 (Nymeyer et al 2011;Maxted et al 2016). The eccentricity of the perturbing planet is however left as a free parameter.…”

“…The first target of interest is WASP-126 because it shows subtle periodic structure in the residuals of the linear ephemeris. WASP-126 b is a 0.28 M Jup mass planet at an orbital period of 3.28 day around a G2 5800K star (Maxted et al 2016). Not much is known beyond the initial discovery of WASP-126 b however it does have a large scale height (∼650 km) and would be an interesting candidate for atmospheric characterization.…”

Comparison of the power-2 limb-darkening law from the STAGGER-grid to Kepler light curves of transiting exoplanets

“…, a 4 . These coefficients may be fixed or the effective temperature used for the interpolation, T eff,ld , can be included as a free parameter in the fit (e.g., Maxted et al 2016).…”