Simultaneous follow-up of planetary transits: revised physical properties for the planetary systems HAT-P-16 and WASP-21

Context. By now more than 300 planets transiting their host star have been found, and much effort is being put into measuring the properties of each system. Light curves of planetary transits often contain deviations from a simple transit shape, and it is generally difficult to differentiate between anomalies of astrophysical nature (e.g. starspots) and correlated noise due to instrumental or atmospheric effects. Our solution is to observe transit events simultaneously with two telescopes located at different observatories. Aims. Using this observational strategy, we look for anomalies in the light curves of two transiting planetary systems and accurately estimate their physical parameters. Methods. We present the first photometric follow-up of the transiting planet HAT-P-16 b, and new photometric observations of WASP-21 b, obtained simultaneously with two medium-class telescopes located in different countries, using the telescope defocussing technique. We modeled these and other published data in order to estimate the physical parameters of the two planetary systems. Results. The simultaneous observations did not highlight particular features in the light curves, which is consistent with the low activity levels of the two stars. For HAT-P-16, we calculated a new ephemeris and found that the planet is 1.3 \sigma colder and smaller (Rb = 1.190 \pm 0.037 RJup) than the initial estimates, suggesting the presence of a massive core. Our physical parameters for this system point towards a younger age than previously thought. The results obtained for WASP-21 reveal lower values for the mass and the density of the planet (by 1.0 \sigma and 1.4 \sigma respectively) with respect to those found in the discovery paper, in agreement with a subsequent study. We found no evidence of any transit timing variations in either system.Comment: 8 pages, 6 figures, accepted for publication in A&

New transit observations for HAT-P-30 b, HAT-P-37 b, TrES-5 b, WASP-28 b, WASP-36 b, and WASP-39 b

We present new transit light curves for planets in six extrasolar planetary systems. They were acquired with 0.4-2.2 m telescopes located in west Asia, Europe, and South America. When combined with literature data, they allowed us to redetermine system parameters in a homogeneous way. Our results for individual systems are in agreement with values reported in previous studies. We refined transit ephemerides and reduced uncertainties of orbital periods by a factor between 2 and 7. No sign of any variations in transit times was detected for the planets studied.Comment: Submitted to Acta Astronomic

High-precision photometry by telescope defocussing - VI. WASP-24, WASP-25 and WASP-26

The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013/) under grant agreement nos. 229517 and 268421. This publication was supported by grants NPRP 09-476-1-078 and NPRP X-019-1-006 from Qatar National Research Fund (a member of Qatar Foundation). TCH acknowledges financial support from the Korea Research Council for Fundamental Science and Technology (KRCF) through the Young Research Scientist Fellowship Programme and is supported by the KASI (Korea Astronomy and Space Science Institute) grant 2012-1-410-02/2013-9-400-00. SG, XW and XF acknowledge the support from NSFC under the grant no. 10873031. The research is supported by the ASTERISK project (ASTERoseismic Investigations with SONG and Kepler) funded by the European Research Council (grant agreement no. 267864). DR, YD, AE, FF (ARC), OW (FNRS research fellow) and J Surdej acknowledge support from the Communauté française de Belgique – Actions de recherche concertées – Académie Wallonie-Europe.We present time series photometric observations of 13 transits in the planetary systems WASP-24, WASP-25 and WASP-26. All three systems have orbital obliquity measurements, WASP-24 and WASP-26 have been observed with Spitzer, and WASP-25 was previously comparatively neglected. Our light curves were obtained using the telescope-defocussing method and have scatters of 0.5–1.2 mmag relative to their best-fitting geometric models. We use these data to measure the physical properties and orbital ephemerides of the systems to high precision, finding that our improved measurements are in good agreement with previous studies. High-resolution Lucky Imaging observations of all three targets show no evidence for faint stars close enough to contaminate our photometry. We confirm the eclipsing nature of the star closest to WASP-24 and present the detection of a detached eclipsing binary within 4.25 arcmin of WASP-26.Publisher PDFPeer reviewe

Modelling and control of a variable-length flexible beam on inspection ground robot

Stabilising an inverted pendulum on a cart is a well-known control problem. This paper proposes the mechanical and control design for solving the oscillation problem of a variable-length flexible beam mounted on a mobile robot. The system under consideration is the robot PovRob, used at the European Organization for Nuclear Research (CERN) for visual and remote inspection tasks of particle accelerators. The flexible beam mounted on the robot houses cameras and sensors. The innovative aspect of the approach concerns the use of actuated masses mounted at the end of the rod, which induces an impulsive moment due to their inertia and angular acceleration. The modelling of the flexible rod has been suitably simplified in a lumped-parameter system, with dynamic parameters related to the rod’s flexibility. A linearisation of the dynamic model allows a linear-quadratic control to stabilise the system. Experimental results support the identification and the validation of the dynamic model, while simulation results evaluate the performances of the designed control law

WASP-167b/KELT-13b: Joint discovery of a hot Jupiter transiting a rapidly-rotating F1V star

peer reviewedWe report the joint WASP/KELT discovery of WASP-167b/KELT-13b, a transiting hot Jupiter with a 2.02-d orbit around a $V$ = 10.5, F1V star with [Fe/H] = 0.1 $\pm$ 0.1. The 1.5 R$_{\rm Jup}$ planet was confirmed by Doppler tomography of the stellar line profiles during transit. We place a limit of $<$ 8 M$_{\rm Jup}$ on its mass. The planet is in a retrograde orbit with a sky-projected spin-orbit angle of $\lambda = -165^{\circ} \pm 5^{\circ}$. This is in agreement with the known tendency for orbits around hotter stars to be more likely to be misaligned. WASP-167/KELT-13 is one of the few systems where the stellar rotation period is less than the planetary orbital period. We find evidence of non-radial stellar pulsations in the host star, making it a $\delta$-Scuti or $\gamma$-Dor variable. The similarity to WASP-33, a previously known hot-Jupiter host with pulsations, adds to the suggestion that close-in planets might be able to excite stellar pulsations

Faint source star planetary microlensing : the discovery of the cold gas giant planet OGLE-2014-BLG-0676Lb

We report the discovery of a planet — OGLE-2014-BLG-0676Lb— via gravitational microlensing. Observations for the lensing event were made by the MOA, OGLE, Wise, RoboNET/LCOGT, MiNDSTEp and μFUN groups. All analyses of the light curve data favour a lens system comprising a planetary mass orbiting a host star. The most favoured binary lens model has a mass ratio between the two lens masses of (4.78 ± 0.13) × 10−3. Subject to some important assumptions, a Bayesian probability density analysis suggests the lens system comprises a 3.09 (+1.02/−1.12) MJ planet orbiting a 0.62(+0.20/−0.22) M⊙ host star at a deprojected orbital separation of 4.40 (+2.16/−1.46) AU. The distance to the lens system is 2.22 (+0.96/−0.83) kpc. Planet OGLE-2014-BLG-0676Lb provides additional data to the growing number of cool planets discovered using gravitational microlensing against which planetary formation theories may be tested. Most of the light in the baseline of this event is expected to come from the lens and thus high-resolution imaging observations could confirm our planetary model interpretation.PostprintPeer reviewe

Complex AGN feedback in the Teacup galaxy: A powerful ionised galactic outflow, jet-ISM interaction, and evidence for AGN-triggered star formation in a giant bubble

\ua9 2023 The Authors. Context. The z ∼ 0.1 type-2 QSO J1430+1339, known as the Teacup , is a complex galaxy showing a loop of ionised gas ∼10 kpc in diameter, co-spatial radio bubbles, a compact (∼1 kpc) jet, and outflow activity. Its closeness offers the opportunity to study in detail the intricate interplay between the central supermassive black hole (SMBH) and the material in and around the galaxy, both the interstellar medium (ISM) and circumgalactic medium (CGM). Aims. We characterise the spatially resolved properties and effects of the galactic ionised gas outflow and compare them with those of the radio jet and with theoretical predictions to infer its acceleration mechanism. Methods. We used VLT/MUSE optical integral field spectroscopic observations to obtain flux, kinematic, and excitation maps of the extended (up to ∼100 kpc) ionised gas and to characterise the properties of stellar populations. We built radial profiles of the outflow properties as a function of distance from the active nucleus, from kiloparsec up to tens of kiloparsec scales, at ∼1 kpc resolution. Results. We detect a velocity dispersion enhancement (≲300 km s-1) elongated over several kiloparsecs perpendicular to the radio jet, the active galactic nucleus (AGN) ionisation lobes, and the fast outflow, similar to what is found in other galaxies hosting compact, low-power jets, indicating that the jet strongly perturbs the host ISM during its passage. We observe a decreasing trend with distance from the nucleus for the outflow properties (mass outflow rate, kinetic rate, momentum rate). The mass outflow rate drops from around 100 M\ub7 yr-1 in the inner 1-2 kpc to \ue2\uc3 \uc2‰ \ub20.1 M\ub7 yr-1 at 30 kpc. The mass outflow rate of the ionised outflow is significantly higher (∼1-8 times) than the molecular one, in contrast with what is often quoted in AGN. Based on energetic and morphological arguments, the driver of the multi-phase outflow is likely a combination of AGN radiation and the jet, or AGN radiation pressure on dust alone. The outflow mass-loading factor is ∼5-10 and the molecular gas depletion time due to the multi-phase outflow is ≲108 yr, indicating that the outflow can significantly affect the star formation and the gas reservoir in the galaxy. However, the fraction of the ionised outflow that is able to escape the dark matter halo potential is likely negligible. We detect blue-coloured continuum emission co-spatial with the ionised gas loop. Here, stellar populations are younger (≳100-150 Myr) than in the rest of the galaxy (∼0.5-1 Gyr). This constitutes possible evidence for star formation triggered at the edge of the bubble due to the compressing action of the jet and outflow (positive feedback ), as predicted by theory. All in all, the Teacup constitutes a rich system in which AGN feedback from outflows and jets, in both its negative and positive flavours, co-exist

New Transit Observations for HAT-P-30 b, HAT-P-37 b, TrES-5 b, WASP-28 b, WASP-36 b and WASP-39 b

We present new transit light curves for planets in six extrasolar planetary systems. They were acquired with 0.4–2.2 m telescopes located in west Asia, Europe, and South America. When combined with literature data, they allowed us to redetermine system parameters in a homogeneous way. Our results for individual systems are in agreement with values reported in previous studies. We refined transit ephemerides and reduced uncertainties of orbital periods by a factor between 2 and 7. No sign of any variations in transit times was detected for the planets studied.Fil: Maciejewski, G.. Nicolaus Copernicus University; PoloniaFil: Dimitrov, D.. Bulgarian Academy Of Sciences; BulgariaFil: Mancini, L.. Max Planck Institute for Astronomy; Alemania. Osservatorio Astrofisico Di Torino; Italia. Istituto Nazionale di Astrofisica; ItaliaFil: Southworth, J.. Keele University; Reino UnidoFil: Ciceri, S.. Max Planck Institute For Astronomy; AlemaniaFil: D'Ago, G.. Istituto Internazionale per gli Alti Studi ; ItaliaFil: Bruni, I.. Osservatorio Astrofisico di Bologna; Italia. Istituto Nazionale di Astrofisica; ItaliaFil: Raetz, St.. Universitat Erlangen-nurmberg. Astronomisches Institut-dr. Karl Remeis-sternwarte & Ecap; Alemania. European Space Agency; Países BajosFil: Nowak, G.. Instituto de Astrofísica de Canarias; España. Nicolaus Copernicus University; Polonia. Universidad de La Laguna; EspañaFil: Ohlert, J.. University of Applied Sciences; Alemania. Michael Adrian Observatorium; AlemaniaFil: Puchalski, D.. Nicolaus Copernicus University; PoloniaFil: Saral, G.. Istanbul University; Turquía. University Of Geneva (ug);Fil: Derman, E.. Ankara University; TurquíaFil: Petrucci, Romina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Jofré, E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Seeliger, M.. Universitat Erlangen-nurmberg. Astronomisches Institut-dr. Karl Remeis-sternwarte & Ecap; AlemaniaFil: Henning, T.. Max Planck Institute for Astronomy; Alemani

Complex AGN feedback in the Teacup galaxy. A powerful ionised galactic outflow, jet-ISM interaction, and evidence for AGN-triggered star formation in a giant bubble

The $z$~0.1 type-2 QSO J1430+1339 (the 'Teacup') is a complex galaxy showing a loop of ionised gas ~10 kpc in diameter, co-spatial radio bubbles, a compact (~1 kpc) jet, and outflow activity. We used VLT/MUSE optical integral field spectroscopic observations to characterise the properties and effects of the galactic ionised outflow from kpc up to tens of kpc scales and compare them with those of the radio jet. We detect a velocity dispersion enhancement (>300 km/s) elongated over several kpc perpendicular to the radio jet, the AGN ionisation lobes, and the fast outflow, similar to what is found in other galaxies hosting compact, low-power jets, indicating that the jet strongly perturbs the host ISM. The mass outflow rate decreases with distance from the nucleus, from around 100 $M_\odot$/yr in the inner 1-2 kpc to <0.1 $M_\odot$/yr at 30 kpc. The ionised mass outflow rate is ~1-8 times higher than the molecular one, in contrast with what is often quoted in AGN. The driver of the multi-phase outflow is likely a combination of AGN radiation and the jet. The outflow mass-loading factor (~5-10) and the molecular gas depletion time (<10$^8$ yr) indicate that the outflow can significantly affect the star formation and the gas reservoir in the galaxy. However, the fraction of the ionised outflow that is able to escape the dark matter halo potential is likely negligible. We detect blue-coloured continuum emission co-spatial with the ionised gas loop. Here, stellar populations are younger (<100-150 Myr) than in the rest of the galaxy (~0.5-1 Gyr). This constitutes possible evidence for star formation triggered at the edge of the bubble due to the compressing action of the jet and outflow ('positive feedback'), as predicted by theory. All in all, the Teacup constitutes a rich system in which AGN feedback from outflows and jets, in both its negative and positive flavours, co-exist.Comment: 26 pages, 16 figures; Astronomy & Astrophysics, in pres

Faint-source-star planetary microlensing: the discovery of the cold gas-giant planet OGLE-2014-BLG-0676Lb

We report the discovery of a planet – OGLE-2014-BLG-0676Lb– via gravitational microlensing. Observations for the lensing event were made by the following groups: Microlensing Observations in Astrophysics; Optical Gravitational Lensing Experiment; Wise Observatory; RoboNET/Las Cumbres Observatory Global Telescope; Microlensing Network for the Detection of Small Terrestrial Exoplanets; and μ-FUN. All analyses of the light-curve data favour a lens system comprising a planetary mass orbiting a host star. The most-favoured binary lens model has a mass ratio between the two lens masses of (4.78 ± 0.13) × 10−3. Subject to some important assumptions, a Bayesian probability density analysis suggests the lens system comprises a 3.09+1.02 −1.12 MJ planet orbiting a 0.62+0.20 −0.22 M host star at a deprojected orbital separation of 4.40+2.16 −1.46 au. The distance to the lens system is 2.22+0.96 −0.83 kpc. Planet OGLE- 2014-BLG-0676Lb provides additional data to the growing number of cool planets discovered using gravitational microlensing against which planetary formation theories may be tested. Most of the light in the baseline of this event is expected to come from the lens and thus high-resolution imaging observations could confirm our planetary model interpretation