The peculiar chemical pattern of the WASP-160 binary system: signatures of planetary formation and evolution?
Emiliano Jofré, Romina Petrucci, Yilen Gómez Maqueo Chew, Ivan Ramírez, Carlos Saffe, Eder Martioli, Andrea Buccino, Martin Mašek, Luciano García, Eliab Canul, Mercedes Gómez
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Accepted for publication in AJ, 28 pages, 13 figures, 5 tables
Wide binary stars with similar components hosting planets provide a favorable opportunity for exploring the star-planet chemical connection. We perform a detailed characterization of the solar-type stars in the WASP-160 binary system. No planet has been reported yet around WASP-160A while WASP-160B is known to host a transiting Saturn-mass planet, WASP-160B b. For this planet, we also derive updated properties from both literature and new observations. Furthermore, using TESS photometry, we constrain the presence of transiting planets around WASP-160A and additional ones around WASP-160B. The stellar characterization includes, for the first time, the computation of high-precision differential atmospheric and chemical abundances of 25 elements based on high-quality Gemini-GRACES spectra. Our analysis reveals evidence of a correlation between the differential abundances and the condensation temperatures of the elements. In particular, we find both a small but significant deficit of volatiles and an enhancement of refractory elements in WASP-160B relative to WASP-160A. After WASP-94, this is the second stellar pair among the shortlist of planet-hosting binaries showing this kind of peculiar chemical pattern. Although we discuss several plausible planet formation and evolution scenarios for WASP-160A and B that could explain the observed chemical pattern, none of them can be conclusively accepted or rejected. Future high-precision photometric and spectroscopic follow-up, as well as high-contrast imaging observations, of WASP-160A and B, might provide further constraints on the real origin of the detected chemical differences.
Detection limits for close eclipsing and transiting sub-stellar and planetary companions to white dwarfs in the WASP survey
我们使用WASP（广角行星搜索）调查的光度数据来探索探测日食和在白矮星附近轨道上的褐矮星、气体巨星和陆地伴星的凌日信号的可能性。我们进行了广泛的蒙特卡罗模拟，我们发现，高斯随机噪声WASP是敏感的同伴小到月球轨道$V\sim$ 12白矮星。对于较暗的恒星，WASP对越来越大的天体很敏感。我们的灵敏度下降的协变噪声结构的存在下的数据，然而地球大小的机构仍然很容易检测到相对较低的S/N数据。我们在WASP档案中的194颗白矮星样本中搜索了日食和凌日信号，但是没有发现伴星的证据。我们用我们的结果对这类系统的频率设定了暂定的上限。虽然我们只能对地球大小或更小的伴星的可能频率施加微弱的限制，但棕矮星和气体巨星（半径为$\simeq$ R $_{jup}$），周期为$\leq$ 0.2天的肯定是罕见的（$<10\%$）。更严格的限制要求更大的白矮星样本，更高的观测节奏和连续覆盖。与WASP观测的节奏相比，白矮星的日食和凌日的持续时间很短，这似乎是限制主序星行星凌日调查的主要因素之一。
Origins of giant planets on tight orbits, so called hot Jupiters, are a long-lasting question in the planetary formation and evolution theory. The answer seems to be hidden in architectures of those systems that remain only partially understood. Using multi-sector time-series photometry from the Transiting Exoplanet Survey Satellite, we searched for additional planets in the KELT-18, KELT-23, KELT-24, Qatar-8, WASP-62, WASP-100, WASP-119, and WASP-126 planetary systems using both the transit technique and transit timing method. Our homogenous analysis has eliminated the presence of transiting …
Uninterrupted observations from space-borne telescopes provide the photometric precision that is required to detect shallow transits of small planets missed by ground-based surveys. We used data from the Transiting Exoplanet Survey Satellite (TESS) to search for nearby planetary companions in 12 planetary systems with hot Jupiters: HD 2685, Qatar-10, WASP-4, WASP-48, WASP-58, WASP-91, WASP-120, WASP-121, WASP-122, WASP-140, XO-6, and XO-7. We also applied the transit timing method based on homogeneously determined mid-transit times in order to search for non-transiting companions that could gr…
WASP-98 is a planetary system containing a hot Jupiter transiting a late-G dwarf. A fainter star 12 arcsec distant has previously been identified as a white dwarf, with a distance and proper motion consistent with a physical association with the planetary system. We present spectroscopy of the white dwarf, with the aim of determining its mass, radius and temperature and hence the age of the system. However, the spectra show the featureless continuum and lack of spectral lines characteristic of the DC class of white dwarfs. We therefore fitted theoretical white dwarf spectra to the ugriz appare…
Massive exoplanets on extremely tight orbits, such as WASP-12 b, induce equilibrium tides in their host stars. Following the orbital motion of the planet, the tidal fluid flow in the star can be detected with the radial velocity method. Its signature manifests as the second harmonics of the orbital frequency that mimics a non-zero orbital eccentricity. Using the new radial velocity measurements acquired with the HARPS-N spectrograph at the Telescopio Nazionale Galileo and combining them with the literature data, we show that the apparent eccentricity of WASP-12 b's orbit is non-zero at a 5.8 s…
We report measurements of the sky-projected spin--orbit angles for three transiting hot Jupiters: two of which are in nearly polar orbits, WASP-100b and WASP-109b, and a third in a low obliquity orbit, WASP-72b. We obtained these measurements by observing the Rossiter--McLaughlin effect over the course of the transits from high resolution spectroscopic observations made with the CYCLOPS2 optical fiber bundle system feeding the UCLES spectrograph on the Anglo-Australian Telescope. The resulting sky-projected spin--orbit angles are $λ= {-7^{\circ}}^{+11^{\circ}}_{-12^{\circ}}$, $λ= {79^{\circ}}^…
Exoplanet discoveries have demonstrated a vast range of planetary system architectures. The demographic of compact planetary systems are especially interesting from the perspective of planetary formation and the evolution of orbital dynamics. Another interesting demographic is that of giant planets in eccentric orbits, since these planets have likely had a dynamical history involving planet-planet scattering events. The WASP-47 system is particularly fascinating since it combines these two demographics, having both compact planetary orbits and a giant planet on an eccentric orbit within the sy…
We present the detection and characterization of the full-orbit phase curve and secondary eclipse of the ultra-hot Jupiter WASP-33b at optical wavelengths, along with the pulsation spectrum of the host star. We analyzed data collected by the Transiting Exoplanet Survey Satellite (TESS) in sector 18. WASP-33b belongs to a very short list of highly irradiated exoplanets that were discovered from the ground and were later visited by TESS. The host star of WASP-33b is of delta Scuti-type and shows nonradial pulsations in the millimagnitude regime, with periods comparable to the period of the prima…
Hot Jupiters are generally observed to lack close planetary companions, a trend that has been interpreted as evidence for high-eccentricity migration. We present the discovery and validation of WASP-132 c (TOI-822.02), a 1.85 $\pm$ 0.10 $R_{\oplus}$ planet on a 1.01 day orbit interior to the hot Jupiter WASP-132 b. Transiting Exoplanet Survey Satellite (TESS) and ground-based follow-up observations, in conjunction with vetting and validation analysis, enable us to rule out common astrophysical false positives and validate the observed transit signal produced by WASP-132 c as a planet. Running …
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
我们已经使用测光从WASP-南仪器，以确定5颗恒星显示行星一样的过渡，在他们的光变曲线。这些恒星的伴星的行星性质已经通过使用瑞士欧拉1.2米望远镜和TRAPPIST望远镜上的EulerCam仪器的测光以及CORALIE摄谱仪获得的光谱学得到证实。发现的行星是热木星系统，轨道周期在2.17到5.75天之间，质量从0.3 M $_{\rm Jup}$到1.2 M $_{\rm Jup}$，半径从1 R $_{\rm Jup}$到1.5 R $_{\rm Jup}$。这些行星围绕明亮的恒星（V = 11-13）运行，其光谱型在F9到G4之间。WASP-126是这个样本中最明亮的行星系，拥有一颗半径大的低质量行星（0.3 M $_{\rm Jup}$，0.95 R $_{\rm Jup}$），使其成为透射光谱学的良好目标。WASP-129 A的高密度表明它是一颗类似于HAT-P-11 A的富氦恒星。WASP-133与其他古老的G型恒星，特别是其他行星宿主恒星相比，具有更高的表面锂丰度。这些行星系是利用地面和空间设施进行后续观测以研究其大气和动力特性的良好目标。
Transits in the planetary system WASP-4 were recently found to occur 80s earlier than expected in observations from the TESS satellite. We present 22 new times of mid-transit that confirm the existence of transit timing variations, and are well fitted by a quadratic ephemeris with period decay dP/dt = -9.2 +/- 1.1 ms/yr. We rule out instrumental issues, stellar activity and the Applegate mechanism as possible causes. The light-time effect is also not favoured due to the non-detection of changes in the systemic velocity. Orbital decay and apsidal precession are plausible but unproven. WASP-4b i…
In this paper, we present high-resolution spectroscopic transit observations from ESPRESSO of the super-Neptune WASP-166~b. In addition to spectroscopic ESPRESSO data, we analyse photometric data from {\sl TESS} of six WASP-166~b transits along with simultaneous NGTS observations of the ESPRESSO runs. These observations were used to fit for the planetary parameters as well as assessing the level of stellar activity (e.g. spot crossings, flares) present during the ESPRESSO observations. We utilise the Reloaded Rossiter McLaughlin (RRM) technique to spatially resolve the stellar surface, charact…
WASP-52b is a low density hot Jupiter orbiting a moderately active K2V star. Previous low-resolution studies have revealed a cloudy atmosphere and found atomic Na above the cloud deck. Here we report the detection of excess absorption at the Na doublet, the H$α$ line, and the K D$_1$ line. We derived a high-resolution transmission spectrum based on three transits of WASP-52b, observed with the ultra stable, high-resolution spectrograph ESPRESSO at the VLT. We measure a line contrast of $1.09\pm 0.16$% for Na D$_1$, $1.31\pm 0.13$% for Na D$_2$, $0.86\pm 0.13$% for H$α$, and $0.46\pm 0.13$% for…
We perform a detailed study of six transiting planetary systems with relatively bright stars close enough to affect observations of these systems. Light curves are analysed taking into account the contaminating light and its uncertainty. We present and apply a method to correct the velocity amplitudes of the host stars for the presence of contaminating light. We determine the physical properties of six systems (WASP-20, WASP-70, WASP-8, WASP-76, WASP-2 and WASP-131) accounting for contaminating light. In the case of WASP-20 the measured physical properties are very different for the three scen…
We characterised five transiting planetary systems (HAT-P-3, HAT-P-12, HAT-P-22, WASP-39 and WASP-60) and determined their sky-projected planet orbital obliquity through the measurement of the RM effect. We used HARPS-N high-precision radial velocity measurements, gathered during transit events, to measure the RM effect in the target systems and determine the sky-projected angle between the planetary orbital plane and the stellar equator. The characterisation of stellar atmospheric parameters was performed exploiting the HARPS-N spectra, using line equivalent width ratios, and spectral synthes…
SALT observations of the Chromospheric Activity of Transiting Planet Hosts: Mass Loss and Star Planet Interactions
我们测量了四个热木星宿主WASP-43，WASP-51/HAT-P-30，WASP-72和WASP-103的色球活动，以寻找由近距离伴星引起的异常值。威尔逊山Ca II H&K S指数是利用南非大型望远镜的罗伯特·斯托比摄谱仪观测到的每颗恒星计算出来的。WASP-43的活动水平相对于它的年龄来说非常高，是所有已知主序星中最高的。我们发现了少量证据表明WASP-103的活性也高于系统年龄的预期。我们认为，WASP-43和WASP-103星-行星相互作用（SPI）可能会增强钙II H&K核心排放。WASP-51/HAT-P-30和WASP-72的活动水平非常低，后者低于主序星和演化星的基底包络线。这可以归因于行星质量损失引起的星周吸收，尽管ISM中的吸收也有贡献。四分之一的已知短周期行星宿主表现出异常低的活动水平，包括具有热木星和低质量伴星的系统。由于SPI可以提高和吸收可以抑制观测到的色球活动的恒星与接近的行星，他们的Ca II H&K活动水平是一个不可靠的年龄指标。由于行星质量损失的吸收而使活动受到抑制的系统是通过透射光谱学检查行星组成的关键目标。
We present the first results from MOPSS, The Michigan Optical Planetary Spectra Survey, aimed at creating a database of optical planetary transmission spectra all observed, reduced, and analyzed with a uniform method for the benefit of enabling comparative exoplanet studies. We discuss our methods, and present results for our first two targets observed with the Magellan Baade 6.5m telescope, one transit of the Hot Jupiter WASP-4b and two transits of the Hot Saturn WASP-52b. Both targets present flat, featureless spectra, corresponding to the presence of aerosols. We find that the cloud decks m…
We present broad-band photometry of eleven planetary transits of the hot Jupiter WASP-74b, using three medium-class telescopes and employing the telescope-defocussing technique. Most of the transits were monitored through I filters and one was simultaneously observed in five optical (U, g', r', i', z') and three near infrared (J, H, K) passbands, for a total of 18 light curves. We also obtained new high-resolution spectra of the host star. We used these new data to review the orbital and physical properties of the WASP-74 planetary system. We were able to better constrain the main system chara…
WASP-18 hosts a massive, very close-in Jupiter-like planet. Despite its young age ($<$1 Gyr), the star presents an anomalously low stellar activity level: the measured logR'$_{\rm HK}$ activity parameter lies slightly below the basal level; there is no significant time-variability in the logR'$_{\rm HK}$ value; there is no detection of the star in the X-rays. We present results of far-UV observations of WASP-18 obtained with COS on board of Hubble Space Telescope aimed at explaining this anomaly. From the star's spectral energy distribution, we infer the extinction (E(B-V) $\approx$ 0.01 mag) …
The hot Jupiter WASP-80b has been identified as a possible excellent target for detecting and measuring HeI absorption in the upper atmosphere. We observed 4 primary transits of WASP-80b in the optical and near-IR using the HARPS-N and GIANO-B high-resolution spectrographs, focusing on the HeI triplet. We further employed a three-dimensional hydrodynamic aeronomy model to understand the observational results. We did not find any signature of planetary absorption at the position of the HeI triplet with an upper limit of 0.7% (i.e. 1.11 planetary radii; 95% confidence level). We re-estimated the…
Transmission spectroscopy provides a powerful probe of the atmospheric properties of transiting exoplanets. To date, studies of exoplanets in transit have focused on inferring their atmospheric properties such as chemical compositions, cloud/haze properties, and temperature structures. However, surface inhomogeneities in the host stars of exoplanets in the form of cool spots and hot faculae can in principle imprint signatures on the observed planetary transit spectrum. Here we present Aura, a new retrieval paradigm for inferring both planetary and stellar properties from a transmission spectru…
To increase the sample size of future atmospheric characterization efforts, we build on the planetary infrared excess (PIE) technique that has been proposed as a means to detect and characterize the thermal spectra of transiting and non-transiting exoplanets using sufficiently broad wavelength coverage to uniquely constrain the stellar and planetary spectral components from spatially unresolved observations. We performed simultaneous retrievals of stellar and planetary spectra for the archetypal planet WASP-43b in its original configuration and a non-transiting configuration to determine the e…
