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See detailOrbital and spectral characterization of the benchmark T-type brown dwarf HD 19467B
Maire, Anne-Lise ULiege; Molaverdikhani, K.; Desidera, S. et al

in Astronomy and Astrophysics (2020), 639

Context. Detecting and characterizing substellar companions for which the luminosity, mass, and age can be determined independently is of utter importance to test and calibrate the evolutionary models due ... [more ▼]

Context. Detecting and characterizing substellar companions for which the luminosity, mass, and age can be determined independently is of utter importance to test and calibrate the evolutionary models due to uncertainties in their formation mechanisms. HD 19467 is a bright and nearby star hosting a cool brown dwarf companion detected with radial velocities and imaging, making it a valuable object for such studies. <BR /> Aims: We aim to further characterize the orbital, spectral, and physical properties of the HD 19467 system. <BR /> Methods: We present new high-contrast imaging data with the SPHERE and NaCo instruments. We also analyze archival data from the instruments HARPS, NaCo, HIRES, UVES, and ASAS. Furthermore, we use proper motion data of the star from HIPPARCOS and Gaia. <BR /> Results: We refined the properties of the host star and derived an age of 8.0[SUP]+2.0[/SUP][SUB]-1.0[/SUB] Gyr based on isochrones, gyrochronology, and chemical and kinematic arguments. This age estimate is slightly younger than previous age estimates of ~9-11 Gyr based on isochrones. No orbital curvature is seen in the current imaging, radial velocity, and astrometric data. From a joint fit of the data, we refined the orbital parameters for HD 19467B, including: a period of 398[SUP]+95[/SUP][SUB]-93[/SUB] yr, an inclination of 129.8[SUP]+8.1[/SUP][SUB]-5.1[/SUB] deg, an eccentricity of 0.56 ± 0.09, a longitude of the ascending node of 134.8 ± 4.5 deg, and an argument of the periastron of 64.2[SUP]+5.5[/SUP][SUB]-6.3[/SUB] deg. We assess a dynamical mass of 74[SUP]+12[/SUP][SUB]-9[/SUB] M[SUB]J[/SUB]. The fit with atmospheric models of the spectrophotometric data of the companion indicates an atmosphere without clouds or with very thin clouds, an effective temperature of 1042[SUP]+77[/SUP][SUB]-71[/SUB] K, and a high surface gravity of 5.34[SUP]+0.8[/SUP][SUB]-0.9[/SUB] dex. The comparison to model predictions of the bolometric luminosity and dynamical mass of HD 19467B, assuming our system age estimate, indicates a better agreement with the Burrows et al. (1997, ApJ, 491, 856) models; whereas, the other evolutionary models used tend to underestimate its cooling rate. <P />The reduced images shown in Fig. 3 are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz- bin/cat/J/A+A/639/A47">http://cdsarc.u-strasbg.fr/viz- bin/cat/J/A+A/639/A47</A> <P />Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 1100.C-0481, 0100.C-0234, 096.C-0602, 072.C-0488, 183.C-0972, 084.D-0965, 188.C-0265, 192.C-0852, and 0100.D-0444. [less ▲]

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See detailThree short-period Jupiters from TESS. HIP 65Ab, TOI-157b, and TOI-169b
Nielsen, L. D.; Brahm, R.; Bouchy, F. et al

in Astronomy and Astrophysics (2020), 639

We report the confirmation and mass determination of three hot Jupiters discovered by the Transiting Exoplanet Survey Satellite (TESS) mission: HIP 65Ab (TOI-129, TIC-201248411) is an ultra-short-period ... [more ▼]

We report the confirmation and mass determination of three hot Jupiters discovered by the Transiting Exoplanet Survey Satellite (TESS) mission: HIP 65Ab (TOI-129, TIC-201248411) is an ultra-short-period Jupiter orbiting a bright (V = 11.1 mag) K4-dwarf every 0.98 days. It is a massive 3.213 ± 0.078 M[SUB]J[/SUB] planet in a grazing transit configuration with an impact parameter of b = 1.17[SUB]-0.08[/SUB][SUP]+0.10[/SUP]. As a result the radius is poorly constrained, 2.03[SUB]-0.49[/SUB][SUP]+0.61[/SUP]R[SUB]J[/SUB]. The planet's distance to its host star is less than twice the separation at which it would be destroyed by Roche lobe overflow. It is expected to spiral into HIP 65A on a timescale ranging from 80 Myr to a few gigayears, assuming a reduced tidal dissipation quality factor of Q[SUB]s[/SUB][SUP]'[/SUP] = 10[SUP]7[/SUP] - 10[SUP]9[/SUP]. We performed a full phase-curve analysis of the TESS data and detected both illumination- and ellipsoidal variations as well as Doppler boosting. HIP 65A is part of a binary stellar system, with HIP 65B separated by 269 AU (3.95 arcsec on sky). TOI-157b (TIC 140691463) is a typical hot Jupiter with a mass of 1.18 ± 0.13 M[SUB]J[/SUB] and a radius of 1.29 ± 0.02 R[SUB]J[/SUB]. It has a period of 2.08 days, which corresponds to a separation of just 0.03 AU. This makes TOI-157 an interesting system, as the host star is an evolved G9 sub-giant star (V = 12.7). TOI-169b (TIC 183120439) is a bloated Jupiter orbiting a V = 12.4 G-type star. It has a mass of 0.79 ±0.06 M[SUB]J[/SUB] and a radius of 1.09[SUB]-0.05[/SUB][SUP]+0.08[/SUP]R[SUB]J[/SUB]. Despite having the longest orbital period (P = 2.26 days) of the three planets, TOI-169b receives the most irradiation and is situated on the edge of the Neptune desert. All three host stars are metal rich with [Fe / H] ranging from 0.18 to0.24. [less ▲]

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See detailHATS-47b, HATS-48Ab, HATS-49b, and HATS-72b: Four Warm Giant Planets Transiting K Dwarfs
Hartman, J. D.; Jordán, Andrés; Bayliss, D. et al

in Astronomical Journal (2020), 159

We report the discovery of four transiting giant planets around K dwarfs. The planets HATS-47b, HATS-48Ab, HATS-49b, and HATS-72b have masses of 0.369[SUB]-0.021[/SUB][SUP]+0.031[/SUP] M_{J}, 0.243[SUB]-0 ... [more ▼]

We report the discovery of four transiting giant planets around K dwarfs. The planets HATS-47b, HATS-48Ab, HATS-49b, and HATS-72b have masses of 0.369[SUB]-0.021[/SUB][SUP]+0.031[/SUP] M_{J}, 0.243[SUB]-0.030[/SUB][SUP]+0.022[/SUP] M_{J}, 0.353[SUB]-0.027[/SUB][SUP]+0.038[/SUP] M_{J}, and 0.1254± 0.0039 M_{J}, respectively, and radii of 1.117± 0.014 R_{J}, 0.800± 0.015 R_{J}, 0.765± 0.013 R_{J}, and 0.7224± 0.0032 R_{J}, respectively. The planets orbit close to their host stars with orbital periods of 3.9228 days, 3.1317 days, 4.1480 days, and 7.3279ays, respectively. The hosts are main-sequence K dwarfs with masses of 0.674[SUB]-0.012[/SUB][SUP]+0.016[/SUP] M_{☉}, 0.7279 ± 0.0066 M_{☉}, 0.7133± 0.0075 M_{☉}, and 0.7311± 0.0028, and with V-band magnitudes of V=14.829± 0.010, 14.35± 0.11, 14.998± 0.040 and 12.469± 0.010. The super-Neptune HATS-72b (a.k.a. WASP-191b and TOI 294.01) was independently identified as a transiting planet candidate by the HATSouth, WASP, and TESS surveys, and we present a combined analysis of all of the data gathered by each of these projects (and their follow-up programs). An exceptionally precise mass is measured for HATS-72b thanks to high-precision radial velocity (RV) measurements obtained with VLT/ESPRESSO, FEROS, HARPS, and Magellan/PFS. We also incorporate TESS observations of the warm Saturn─hosting systems HATS-47 (a.k.a. TOI 1073.01), HATS-48A, and HATS-49. HATS-47 was independently identified as a candidate by the TESS team, while the other two systems were not previously identified from the TESS data. The RV orbital variations are measured for these systems using Magellan/PFS. HATS-48A has a resolved 5.4" neighbor in Gaia DR2, which is a common-proper-motion binary star companion to HATS-48A with a mass of 0.22 M_{☉} and a current projected physical separation of ∼1400 au. [less ▲]

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See detailSPHERE+: Imaging young Jupiters down to the snowline
Boccaletti, A.; Chauvin, G.; Mouillet, D. et al

E-print/Working paper (2020)

SPHERE (Beuzit et al,. 2019) has now been in operation at the VLT for more than 5 years, demonstrating a high level of performance. SPHERE has produced outstanding results using a variety of operating ... [more ▼]

SPHERE (Beuzit et al,. 2019) has now been in operation at the VLT for more than 5 years, demonstrating a high level of performance. SPHERE has produced outstanding results using a variety of operating modes, primarily in the field of direct imaging of exoplanetary systems, focusing on exoplanets as point sources and circumstellar disks as extended objects. The achievements obtained thus far with SPHERE (~200 refereed publications) in different areas (exoplanets, disks, solar system, stellar physics...) have motivated a large consortium to propose an even more ambitious set of science cases, and its corresponding technical implementation in the form of an upgrade. The SPHERE+ project capitalizes on the expertise and lessons learned from SPHERE to push high contrast imaging performance to its limits on the VLT 8m-telescope. The scientific program of SPHERE+ described in this document will open a new and compelling scientific window for the upcoming decade in strong synergy with ground-based facilities (VLT/I, ELT, ALMA, and SKA) and space missions (Gaia, JWST, PLATO and WFIRST). While SPHERE has sampled the outer parts of planetary systems beyond a few tens of AU, SPHERE+ will dig into the inner regions around stars to reveal and characterize by mean of spectroscopy the giant planet population down to the snow line. Building on SPHERE's scientific heritage and resounding success, SPHERE+ will be a dedicated survey instrument which will strengthen the leadership of ESO and the European community in the very competitive field of direct imaging of exoplanetary systems. With enhanced capabilities, it will enable an even broader diversity of science cases including the study of the solar system, the birth and death of stars and the exploration of the inner regions of active galactic nuclei. [less ▲]

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See detailThree Short Period Jupiters from TESS
Nielsen, L. D.; Brahm, R.; Bouchy, F. et al

E-print/Working paper (2020)

We report the confirmation and mass determination of three hot Jupiters discovered by the Transiting Exoplanet Survey Satellite (TESS) mission: HIP 65Ab (TOI-129, TIC-201248411) is an ultra-short-period ... [more ▼]

We report the confirmation and mass determination of three hot Jupiters discovered by the Transiting Exoplanet Survey Satellite (TESS) mission: HIP 65Ab (TOI-129, TIC-201248411) is an ultra-short-period Jupiter orbiting a bright (V=11.1 mag) K4-dwarf every 0.98 days. It is a massive 3.213 +/- 0.078 Mjup planet in a grazing transit configuration with impact parameter b = 1.17 +0.10/-0.08. As a result the radius is poorly constrained, 2.03 +0.61/-0.49 Rjup. We perform a full phase-curve analysis of the TESS data and detect both illumination- and ellipsoidal variations as well as Doppler boosting. HIP 65A is part of a binary stellar system, with HIP 65B separated by 269 AU (3.95 arcsec on sky). TOI-157b (TIC 140691463) is a typical hot Jupiter with a mass 1.18 +/- 0.13 Mjup and radius 1.29 +/- 0.02 Rjup. It has a period of 2.08 days, which corresponds to a separation of just 0.03 AU. This makes TOI-157 an interesting system, as the host star is an evolved G9 sub-giant star (V=12.7). TOI-169b (TIC 183120439) is a bloated Jupiter orbiting a V=12.4 G-type star. It has a mass of 0.79 +/- 0.06 Mjup and radius 1.09 +0.08/-0.05 Rjup. Despite having the longest orbital period (P=2.26 days) of the three planets, TOI-169b receives the most irradiation and is situated on the edge of the Neptune desert. All three host stars are metal rich with Fe/H ranging from 0.18 - 0.24. [less ▲]

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See detailVLT/SPHERE exploration of the young multiplanetary system PDS70
Mesa, D.; Keppler, M.; Cantalloube, F. et al

in Astronomy and Astrophysics (2019), 632

Context. PDS 70 is a young (5.4 Myr), nearby ( 113 pc) star hosting a known transition disk with a large gap. Recent observations with SPHERE and NACO in the near-infrared (NIR) allowed us to detect a ... [more ▼]

Context. PDS 70 is a young (5.4 Myr), nearby ( 113 pc) star hosting a known transition disk with a large gap. Recent observations with SPHERE and NACO in the near-infrared (NIR) allowed us to detect a planetary mass companion, PDS 70 b, within the disk cavity. Moreover, observations in H[SUB]α[/SUB] with MagAO and MUSE revealed emission associated to PDS 70 b and to another new companion candidate, PDS 70 c, at a larger separation from the star. PDS 70 is the only multiple planetary system at its formation stage detected so far through direct imaging. <BR /> Aims: Our aim is to confirm the discovery of the second planet PDS 70 c using SPHERE at VLT, to further characterize its physical properties, and search for additional point sources in this young planetary system. <BR /> Methods: We re-analyzed archival SPHERE NIR observations and obtained new data in Y, J, H and K spectral bands for a total of four different epochs. The data were reduced using the data reduction and handling pipeline and the SPHERE data center. We then applied custom routines (e.g., ANDROMEDA and PACO) to subtract the starlight. <BR /> Results: We re-detect both PDS 70 b and c and confirm that PDS 70 c is gravitationally bound to the star. We estimate this second planet to be less massive than 5 M[SUB]Jup[/SUB] and with a T[SUB]eff[/SUB] around 900 K. Also, it has a low gravity with logg between 3.0 and 3.5 dex. In addition, a third object has been identified at short separation ( 0.12'') from the star and gravitationally bound to the star. Its spectrum is however very blue, meaning that we are probably seeing stellar light reflected by dust and our analysis seems to demonstrate that it is a feature of the inner disk. We cannot however completely exclude the possibility that it is a planetary mass object enshrouded by a dust envelope. In this latter case, its mass should be of the order of a few tens of M[SUB]⊕[/SUB]. Moreover, we propose a possible structure for the planetary system based on our data, and find that this structure cannot be stable on a long timescale. <P />The reduced images are also available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz- bin/cat/J/A+A/632/A25">http://cdsarc.u-strasbg.fr/viz- bin/cat/J/A+A/632/A25</A> <P />Based on observation made with European Southern Observatory (ESO) telescopes at Paranal Observatory in Chile, under programs ID 095.C-0298(B), 1100.C-0481(D), 1100.C-0481(L) and 1100.C-0481(M). [less ▲]

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See detailRefPlanets: Search for reflected light from extra-solar planets with SPHERE/ZIMPOL
Hunziker, S.; Schmid, H. M.; Mouillet, D. et al

in Astronomy and Astrophysics (2019), in press

RefPlanets is a guaranteed time observation (GTO) programme that uses the Zurich IMaging POLarimeter (ZIMPOL) of SPHERE/VLT for a blind search for exoplanets in wavelengths from 600-900 nm. The goals of ... [more ▼]

RefPlanets is a guaranteed time observation (GTO) programme that uses the Zurich IMaging POLarimeter (ZIMPOL) of SPHERE/VLT for a blind search for exoplanets in wavelengths from 600-900 nm. The goals of this study are the characterization of the unprecedented high polarimetic contrast and polarimetric precision capabilities of ZIMPOL for bright targets, the search for polarized reflected light around some of the closest bright stars to the Sun and potentially the direct detection of an evolved cold exoplanet for the first time. For our observations of Alpha Cen A and B, Sirius A, Altair, Eps Eri and Tau Ceti we used the polarimetric differential imaging (PDI) mode of ZIMPOL which removes the speckle noise down to the photon noise limit for angular separations >0.6". We describe some of the instrumental effects that dominate the noise for smaller separations and explain how to remove these additional noise effects in post-processing. We then combine PDI with angular differential imaging (ADI) as a final layer of post-processing to further improve the contrast limits of our data at these separations. For good observing conditions we achieve polarimetric contrast limits of 15.0-16.3 mag at the effective inner working angle of about 0.13", 16.3-18.3 mag at 0.5" and 18.8-20.4 mag at 1.5". The contrast limits closer in (<0.6") depend significantly on the observing conditions, while in the photon noise dominated regime (>0.6"), the limits mainly depend on the brightness of the star and the total integration time. We compare our results with contrast limits from other surveys and review the exoplanet detection limits obtained with different detection methods. For all our targets we achieve unprecedented contrast limits. Despite the high polarimetric contrasts we are not able to find any additional companions or extended polarized light sources in the data that has been taken so far. [less ▲]

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See detailOrbital and spectral analysis of the benchmark brown dwarf HD 4747B
Peretti, S.; Ségransan, D.; Lavie, B. et al

in Astronomy and Astrophysics (2019), 631

Context. The study of high-contrast imaged brown dwarfs and exoplanets depends strongly on evolutionary models. To estimate the mass of a directly imaged substellar object, its extracted photometry or ... [more ▼]

Context. The study of high-contrast imaged brown dwarfs and exoplanets depends strongly on evolutionary models. To estimate the mass of a directly imaged substellar object, its extracted photometry or spectrum is used and adjusted with model spectra together with the estimated age of the system. These models still need to be properly tested and constrained. HD 4747B is a brown dwarf close to the H burning mass limit, orbiting a nearby (d = 19.25 ± 0.58 pc), solar-type star (G9V); it has been observed with the radial velocity method for over almost two decades. Its companion was also recently detected by direct imaging, allowing a complete study of this particular object. <BR /> Aims: We aim to fully characterize HD 4747B by combining a well-constrained dynamical mass and a study of its observed spectral features in order to test evolutionary models for substellar objects and to characterize its atmosphere. <BR /> Methods: We combined the radial velocity measurements of High Resolution Echelle Spectrometer (HIRES) and CORALIE taken over two decades and high-contrast imaging of several epochs from NACO, NIRC2, and SPHERE to obtain a dynamical mass. From the SPHERE data we obtained a low-resolution spectrum of the companion from Y to H band, and two narrow band-width photometric measurements in the K band. A study of the primary star also allowed us to constrain the age of the system and its distance. <BR /> Results: Thanks to the new SPHERE epoch and NACO archival data combined with previous imaging data and high- precision radial velocity measurements, we were able to derive a well- constrained orbit. The high eccentricity (e = 0.7362 ± 0.0025) of HD 4747B is confirmed, and the inclination and the semi-major axis are derived (i = 47.3 ± 1.6°, a = 10.01 ± 0.21 au). We derive a dynamical mass of m[SUB]B[/SUB] = 70.0 ± 1.6 M[SUB]Jup[/SUB], which is higher than a previous study but in better agreement with the models. By comparing the object with known brown dwarfs spectra, we derive a spectral type of L9 and an effective temperature of 1350 ± 50 K. With a retrieval analysis we constrain the oxygen and carbon abundances and compare them with the values from the HR 8799 planets. <P />Based on observations made with the instrument SPHERE (Prog. ID 198.C-0209) and NaCo (Prog. ID 081.C-0917(A)) at the Paranal observatory and with the CORALIE echelle spectrograph mounted on the 1.2 m Swiss telescope at La Silla Observatory. [less ▲]

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See detailWASP-South hot Jupiters: WASP-178b, WASP-184b, WASP-185b, and WASP-192b
Hellier, Coel; Anderson, D. R.; Barkaoui, Khalid ULiege et al

in Monthly Notices of the Royal Astronomical Society (2019), 490

We report on four new transiting hot Jupiters discovered by the WASP- South survey. WASP-178b transits a V = 9.9, A1V star with T[SUB]eff[/SUB] = 9350 ± 150 K, the second-hottest transit host known. It ... [more ▼]

We report on four new transiting hot Jupiters discovered by the WASP- South survey. WASP-178b transits a V = 9.9, A1V star with T[SUB]eff[/SUB] = 9350 ± 150 K, the second-hottest transit host known. It has a highly bloated radius of 1.81 ± 0.09 R[SUB]Jup[/SUB], in line with the known correlation between high irradiation and large size. With an estimated temperature of 2470 ± 60 K, the planet is one of the best targets for studying ultrahot Jupiters that is visible from the Southern hemisphere. The three host stars WASP-184, WASP-185, and WASP-192 are all post-main-sequence G0 stars of ages 4-8 Gyr. The larger stellar radii (1.3-1.7 M[SUB]☉[/SUB]) mean that the transits are relatively shallow (0.7-0.9 per cent) even though the planets have moderately inflated radii of 1.2-1.3 R[SUB]Jup[/SUB]. WASP-185b has an eccentric orbit (e = 0.24) and a relatively long orbital period of 9.4 d. A star that is 4.6 arcsec from WASP-185 and 4.4 mag fainter might be physically associated. [less ▲]

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See detailWASP-169, WASP-171, WASP-175, and WASP-182: three hot Jupiters and one bloated sub-Saturn mass planet discovered by WASP-South
Nielsen, L. D.; Bouchy, F.; Turner, O. D. et al

in Monthly Notices of the Royal Astronomical Society (2019), 489(2), 2478-2487

We present the discovery of four new giant planets from the Wide Angle Search for Planets-South (WASP-South), three hot Jupiters and one bloated sub-Saturn mass planet: WASP-169b, WASP-171b, WASP-175b ... [more ▼]

We present the discovery of four new giant planets from the Wide Angle Search for Planets-South (WASP-South), three hot Jupiters and one bloated sub-Saturn mass planet: WASP-169b, WASP-171b, WASP-175b, and WASP-182b. Besides the discovery photometry from WASP-South we use radial velocity measurements from CORALIE and HARPS and follow-up photometry from EulerCam, TRAPPIST-North and -South, and SPECULOOS. WASP-169b is a low-density Jupiter (M=0.561 ± 0.061 {M_Jup}, R=1.304^{+0.150}_{-0.073} {R_Jup}) orbiting a V = 12.17 F8 subgiant in a 5.611 d orbit. WASP-171b is a typical hot Jupiter (M=1.084 ± 0.094 {M_Jup}, R=0.98^{+0.07}_{-0.04} {R_Jup}, P = 3.82 d) around a V = 13.05 G0 star. We find a linear drift in the radial velocities of WASP-171 spanning 3.5 yr, indicating the possibility of an additional outer planet or stellar companion. WASP-175b is an inflated hot Jupiter (M = 0.99 ± 0.13 M[SUB]Jup[/SUB], R = 1.208 ± 0.081 R[SUB]Jup[/SUB], P = 3.07 d) around a V = 12.04 F7 star, which possibly is part of a binary system with a star 7.9 arcsec away. WASP-182b is a bloated sub-Saturn mass planet (M = 0.148 ± 0.011 M[SUB]Jup[/SUB], R = 0.850 ± 0.030 R[SUB]Jup[/SUB]) around a metal-rich V = 11.98 G5 star ([Fe/H] = 0.27 ± 0.11). With an orbital period of P = 3.377 d, it sits right in the apex of the sub-Jovian desert, bordering the upper and lower edge of the desert in both the mass-period and radius-period plane. WASP-169b, WASP- 175b, and WASP-182b are promising targets for atmospheric characterization through transmission spectroscopy, with expected transmission signals of 121, 150, and 264 ppm, respectively. [less ▲]

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See detailSuperWASP dispositions and false positive catalogue
Schanche, N.; Collier Cameron, A.; Almenara, J. M. et al

in Monthly Notices of the Royal Astronomical Society (2019), 488

SuperWASP, the Northern hemisphere WASP observatory, has been observing the skies from La Palma since 2004. In that time, more than 50 planets have been discovered with data contributions from SuperWASP ... [more ▼]

SuperWASP, the Northern hemisphere WASP observatory, has been observing the skies from La Palma since 2004. In that time, more than 50 planets have been discovered with data contributions from SuperWASP. In the process of validating planets, many false-positive candidates have also been identified. The TESS telescope is set to begin observations of the northern sky in 2019. Similar to the WASP survey, the TESS pixel size is relatively large (13 arcsec for WASP and 21 arcsec for TESS), making it susceptible to many blended signals and false detections caused principally by grazing and blended stellar eclipsing binary systems. In order to reduce duplication of effort on targets, we present a catalogue of 1 041 Northern hemisphere SuperWASP targets that have been rejected as planetary transits through follow-up observation. [less ▲]

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See detailWASP-180Ab: Doppler tomography of an hot Jupiter orbiting the primary star in a visual binary
Temple, L. Y.; Hellier, C.; Anderson, D. R. et al

in Monthly Notices of the Royal Astronomical Society (2019)

We report the discovery and characterisation of WASP-180Ab, a hot Jupiter confirmed by the detection of its Doppler shadow and by measuring its mass using radial velocities. We find the 0.9 ± 0.1 M[SUB ... [more ▼]

We report the discovery and characterisation of WASP-180Ab, a hot Jupiter confirmed by the detection of its Doppler shadow and by measuring its mass using radial velocities. We find the 0.9 ± 0.1 M[SUB]Jup[/SUB], 1.24 ± 0.04 R[SUB]Jup[/SUB] planet to be in a misaligned, retrograde orbit around an F7 star with T[SUB]eff[/SUB] = 6500 K and a moderate rotation speed of vsin i[SUB]⋆[/SUB] = 19.9 km s[SUP]-1[/SUP]. The host star is the primary of a V = 10.7 binary, where a secondary separated by ̃5″ (̃1200 AU) contributes ̃ 30% of the light. WASP-180Ab therefore adds to a small sample of transiting hot Jupiters known in binary systems. A 4.6-day modulation seen in the WASP data is likely to be the rotational modulation of the companion star, WASP-180B. [less ▲]

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See detailWASP-166b: a bloated super-Neptune transiting a V = 9 star
Hellier, Coel; Anderson, D. R.; Triaud, A. H. M. J. et al

in Monthly Notices of the Royal Astronomical Society (2019), 488

We report the discovery of WASP-166b, a super-Neptune planet with a mass of 0.1 M[SUB]Jup[/SUB] (1.9 M[SUB]Nep[/SUB]) and a bloated radius of 0.63 R[SUB]Jup[/SUB]. It transits a V = 9.36, F9V star in a 5 ... [more ▼]

We report the discovery of WASP-166b, a super-Neptune planet with a mass of 0.1 M[SUB]Jup[/SUB] (1.9 M[SUB]Nep[/SUB]) and a bloated radius of 0.63 R[SUB]Jup[/SUB]. It transits a V = 9.36, F9V star in a 5.44-d orbit that is aligned with the stellar rotation axis (sky-projected obliquity angle λ = 3 ± 5 deg). Variations in the radial-velocity measurements are likely the result of magnetic activity over a 12-d stellar rotation period. WASP-166b appears to be a rare object within the `Neptune desert'. [less ▲]

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See detailThree hot-Jupiters on the upper edge of the mass-radius distribution: WASP-177, WASP-181, and WASP-183
Turner, Oliver D.; Anderson, D. R.; Barkaoui, K. et al

in Monthly Notices of the Royal Astronomical Society (2019), 485

We present the discovery of three transiting planets from the WASP survey, two hot-Jupiters: WASP-177 b (˜0.5 M[SUB]Jup[/SUB], ˜1.6 R[SUB]Jup[/SUB]) in a 3.07-d orbit of a V = 12.6 K2 star, WASP-183 b (˜0 ... [more ▼]

We present the discovery of three transiting planets from the WASP survey, two hot-Jupiters: WASP-177 b (˜0.5 M[SUB]Jup[/SUB], ˜1.6 R[SUB]Jup[/SUB]) in a 3.07-d orbit of a V = 12.6 K2 star, WASP-183 b (˜0.5 M[SUB]Jup[/SUB], ˜1.5 R[SUB]Jup[/SUB]) in a 4.11-d orbit of a V = 12.8 G9/K0 star; and one hot-Saturn planet WASP-181 b (˜0.3 M[SUB]Jup[/SUB], ˜1.2 R[SUB]Jup[/SUB]) in a 4.52-d orbit of a V = 12.9 G2 star. Each planet is close to the upper bound of mass-radius space and has a scaled semimajor axis, a/R[SUB]*[/SUB], between 9.6 and 12.1. These lie in the transition between systems that tend to be in orbits that are well aligned with their host-star's spin and those that show a higher dispersion. [less ▲]

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See detailHint of curvature in the orbital motion of the exoplanet 51 Eridani b using 3 yr of VLT/SPHERE monitoring
Maire, Anne-Lise ULiege; Rodet, L.; Cantalloube, F. et al

in Astronomy and Astrophysics (2019), 624

Context. The 51 Eridani system harbors a complex architecture with its primary star forming a hierarchical system with the binary GJ 3305AB at a projected separation of 2000 au, a giant planet orbiting ... [more ▼]

Context. The 51 Eridani system harbors a complex architecture with its primary star forming a hierarchical system with the binary GJ 3305AB at a projected separation of 2000 au, a giant planet orbiting the primary star at 13 au, and a low-mass debris disk around the primary star with possible cold and warm components inferred from the spectral energy distribution. <BR /> Aims: We aim to better constrain the orbital parameters of the known giant planet. <BR /> Methods: We monitored the system over three years from 2015 to 2018 with the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instrument at the Very Large Telescope (VLT). <BR /> Results: We measure an orbital motion for the planet of 130 mas with a slightly decreasing separation ( 10 mas) and find a hint of curvature. This potential curvature is further supported at 3σ significance when including literature Gemini Planet Imager (GPI) astrometry corrected for calibration systematics. Fits of the SPHERE and GPI data using three complementary approaches provide broadly similar results. The data suggest an orbital period of 32[SUB]-9[/SUB][SUP]+17[/SUP] yr (i.e., 12[SUB]-2[/SUB][SUP]+4[/SUP] au in semi-major axis), an inclination of 133[SUB]-7[/SUB][SUP]+14[/SUP] deg, an eccentricity of 0.45[SUB]-0.15[/SUB][SUP]+0.10[/SUP], and an argument of periastron passage of 87[SUB]-30[/SUB][SUP]+34[/SUP] deg [mod 180°]. The time at periastron passage and the longitude of node exhibit bimodal distributions because we do not yet detect whether the planet is accelerating or decelerating along its orbit. Given the inclinations of the orbit and of the stellar rotation axis (134-144°), we infer alignment or misalignment within 18° for the star-planet spin- orbit. Further astrometric monitoring in the next 3-4 yr is required to confirm at a higher significance the curvature in the motion of the planet, determine if the planet is accelerating or decelerating on its orbit, and further constrain its orbital parameters and the star-planet spin-orbit. <P />The fitted orbits and the histogram distributions of the orbital parameters are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A+A/624/A118">http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A+A/624/A118</A>Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 095.C-0298, 096.C-0241, 198.C-0209, and 1100.C-0481. [less ▲]

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See detailThe EBLM Project VI. The mass and radius of five low-mass stars in F+M binaries discovered by the WASP survey
Gill, Samuel; Maxted, Pierre F.L.; Evans, J. A. et al

in Astronomy and Astrophysics (2019)

Some M-dwarfs around F-/G-type stars have been measured to be hotter and larger than predicted by stellar evolution models. Inconsistencies between observations and models need addressing with more mass ... [more ▼]

Some M-dwarfs around F-/G-type stars have been measured to be hotter and larger than predicted by stellar evolution models. Inconsistencies between observations and models need addressing with more mass, radius and luminosity measurements of low-mass stars to test and refine evolutionary models. Our aim is to measure the masses, radii and ages of the stars in five low-mass eclipsing binary systems discovered by the WASP survey. We use WASP photometry to establish eclipse-time ephemerides and to obtain initial estimates for the transit depth and width. Radial velocity measurements were simultaneously fitted with follow-up photometry to find the best-fitting orbital solution. This solution was combined with measurements of atmospheric parameters to interpolate evolutionary models and estimate the mass of the primary star, and the mass and radius of the M-dwarf companion. We assess how the best fitting orbital solution changes if an alternative limb- darkening law is used and quantify the systematic effects of unresolved companions. We also gauge how the best-fitting evolutionary model changes if different values are used for the mixing length parameter and helium enhancement. We report the mass and radius of five M-dwarfs and find little evidence of inflation with respect to evolutionary models. The primary stars in two systems are near the ``blue hook'' stage of their post sequence evolution, resulting in two possible solutions for mass and age. We find that choices in helium enhancement and mixing- length parameter can introduce an additional 3-5\,\% uncertainty in measured M-dwarf mass. Unresolved companions can introduce an additional 3-8\% uncertainty in the radius of an M-dwarf, while the choice of limb- darkening law can introduce up to an additional 2\% uncertainty. [less ▲]

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See detailWASP-190b: Tomographic Discovery of a Transiting Hot Jupiter
Temple, L. Y.; Hellier, C.; Almleaky, Y. et al

in Astronomical Journal (2019), 157

We report the discovery of WASP-190b, an exoplanet on a 5.37 day orbit around a mildly evolved F6 IV-V star with V = 11.7, {T}[SUB]eff[/SUB]} = 6400 ± 100 K, M [SUB]*[/SUB] = 1.35 ± 0.05 M [SUB]⊙[/SUB ... [more ▼]

We report the discovery of WASP-190b, an exoplanet on a 5.37 day orbit around a mildly evolved F6 IV-V star with V = 11.7, {T}[SUB]eff[/SUB]} = 6400 ± 100 K, M [SUB]*[/SUB] = 1.35 ± 0.05 M [SUB]⊙[/SUB], and R [SUB]*[/SUB] = 1.6 ± 0.1 R [SUB]⊙[/SUB]. The planet has a radius of R [SUB]P[/SUB] = 1.15 ± 0.09 R [SUB]Jup[/SUB] and a mass of M [SUB]P[/SUB] = 1.0 ± 0.1 M [SUB]Jup[/SUB], making it a mildly inflated hot Jupiter. It is the first hot Jupiter confirmed via Doppler tomography with an orbital period of >5 days. The orbit is also marginally misaligned with respect to the stellar rotation, with λ = 21° ± 6° measured using Doppler tomography. [less ▲]

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See detailDiscovery of three new transiting hot Jupiters: WASP-161 b, WASP-163 b and WASP-170 b
Barkaoui, K.; Burdanov, Artem ULiege; Hellier, C. et al

in Astronomical Journal (2019), 157(2),

We present the discovery by the WASP-South transit survey of three new transiting hot Jupiters, WASP-161 b, WASP-163 b and WASP-170 b. Follow-up radial velocities obtained with the Euler/CORALIE ... [more ▼]

We present the discovery by the WASP-South transit survey of three new transiting hot Jupiters, WASP-161 b, WASP-163 b and WASP-170 b. Follow-up radial velocities obtained with the Euler/CORALIE spectrograph and high-precision transit light curves obtained with the TRAPPIST-North, TRAPPIST-South, SPECULOOS-South, NITES, and Euler telescopes have enabled us to determine the masses and radii for these transiting exoplanets. WASP-161\,b completes an orbit around its $V=11.1$ F6V-type host star in 5.406 days, and has a mass and radius of $2.5\pm 0.2$$M_{Jup}$ and $1.14\pm 0.06$ $R_{Jup}$ respectively. WASP-163\,b has an orbital period of 1.609 days, a mass of $1.9\pm0.2$ $M_{Jup}$, and a radius of $1.2\pm0.1$ $R_{Jup}$. Its host star is a $V=12.5$ G8-type dwarf. WASP-170\,b is on a 2.344 days orbit around a G1V-type star of magnitude $V=12.8$. It has a mass of $1.7\pm0.2$ $M_{Jup}$ and a radius of $1.14\pm0.09$ $R_{Jup}$. Given their irradiations ($\sim10^9$ erg.s$^{-1}$.cm$^{-2}$) and masses, the three new planets sizes are in good agreement with classical structure models of irradiated giant planets. [less ▲]

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See detailSpectral and orbital characterisation of the directly imaged giant planet HIP 65426 b
Cheetham, A. C.; Samland, M.; Brems, S. S. et al

in Astronomy and Astrophysics (2019), 622

HIP 65426 b is a recently discovered exoplanet imaged during the course of the SPHERE-SHINE survey. Here we present new L' and M' observations of the planet from the NACO instrument at the VLT from the ... [more ▼]

HIP 65426 b is a recently discovered exoplanet imaged during the course of the SPHERE-SHINE survey. Here we present new L' and M' observations of the planet from the NACO instrument at the VLT from the NACO-ISPY survey, as well as a new Y -H spectrum and K-band photometry from SPHERE-SHINE. Using these data, we confirm the nature of the companion as a warm, dusty planet with a mid-L spectral type. From comparison of its SED with the BT-Settl atmospheric models, we derive a best-fit effective temperature of T[SUB]eff[/SUB] = 1618 ± 7 K, surface gravity log g = 3.78[SUB]-0.03[/SUB][SUP]+0.04[/SUP] and radius R = 1.17 ± 0.04R[SUB]J[/SUB] (statistical uncertainties only). Using the DUSTY and COND isochrones we estimate a mass of 8 ± 1M[SUB]J[/SUB]. Combining the astrometric measurements from our new datasets and from the literature, we show the first indications of orbital motion of the companion (2.6σ significance)and derive preliminary orbital constraints. We find a highly inclined orbit (i = 1.07[SUB]-10[/SUB][SUP]+13[/SUP] deg) with an orbital period of 800[SUB]-400[/SUB][SUP]+1200[/SUP] yr. We also report SPHERE sparse aperture masking observations that investigate the possibility that HIP 65426 b was scattered onto its current orbit by an additional companion at a smaller orbital separation. From this data we rule out the presence of brown dwarf companions with masses greater than 16 M[SUB]J[/SUB] at separations larger than 3 AU, significantly narrowing the parameter space for such a companion. <P />Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 199.C-0065 (PI: Launhardt), 198.C-0209 (PI: Beuzit) and 1100.C-0481 (PI: Beuzit). [less ▲]

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See detailSPHERE dynamical and spectroscopic characterization of HD 142527B
Claudi, R.; Maire, Anne-Lise ULiege; Mesa, D. et al

in Astronomy and Astrophysics (2019), 622

<BR /> Aims: HD 142527 is one of the most frequently studied Herbig Ae/Be stars with a transitional disk that hosts a large cavity that is up to about 100 au in radius. For this reason, it has been ... [more ▼]

<BR /> Aims: HD 142527 is one of the most frequently studied Herbig Ae/Be stars with a transitional disk that hosts a large cavity that is up to about 100 au in radius. For this reason, it has been included in the guaranteed time observation (GTO) SpHere INfrared survey for Exoplanets (SHINE) as part of the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) at the Very Large Telescope (VLT) in order to search for low-mass companions that might explain the presence of the gap. SHINE is a large survey within about 600 young nearby stars are observed with SPHERE with the aim to constrain the occurrence and orbital properties of the giant planet population at large (> 5 au) orbital separation around young stars. <BR /> Methods: We used the IRDIFS observing mode of SPHERE (IRDIS short for infrared dual imaging and spectrograph plus IFS or integral field spectrograph) without any coronagraph in order to search for and characterize companions as close as 30 mas of the star. Furthermore, we present the first observations that ever used the sparse aperture mask (SAM) for SPHERE both in IRDIFS and IRDIFS_EXT modes. All the data were reduced using the dedicated SPHERE pipeline and dedicated algorithms that make use of the principal component analysis (PCA) and reference differential imaging (RDI) techniques. <BR /> Results: We detect the accreting low-mass companion HD 142527B at a separation of 73 mas (11.4 au) from the star. No other companions with mass greater than 10 M[SUB]J[/SUB] are visible in the field of view of IFS (̃100 au centered on the star) or in the IRDIS field of view (̃400 au centered on the star). Measurements from IFS, SAM IFS, and IRDIS suggest an M6 spectral type for HD 142527B, with an uncertainty of one spectral subtype, compatible with an object of M = 0.11 ± 0.06 M[SUB]☉[/SUB] and R = 0.15 ± 0.07 R[SUB]☉[/SUB]. The determination of the mass remains a challenge using contemporary evolutionary models, as they do not account for the energy input due to accretion from infalling material. We consider that the spectral type of the secondary may also be earlier than the type we derived from IFS spectra. From dynamical considerations, we further constrain the mass to 0.26[SUP]+0.16[/SUP][SUB]-0.14[/SUB] M[SUB]☉[/SUB], which is consistent with both our spectroscopic analysis and the values reported in the literature. Following previous methods, the lower and upper dynamical mass values correspond to a spectral type between M2.5 and M5.5 for the companion. By fitting the astrometric points, we find the following orbital parameters: a period of P = 35 - 137 yr; an inclination of i = 121 - 130°, a value of Ω = 124 - 135° for the longitude of node, and an 68% confidence interval of ̃18 - 57 au for the separation at periapsis. Eccentricity and time at periapsis passage exhibit two groups of values: ̃0.2-0.45 and ̃0.45-0.7 for e, and ̃2015-2020 and ̃2020-2022 for T[SUB]0[/SUB]. While these orbital parameters might at first suggest that HD 142527B is not the companion responsible for the outer disk truncation, a previous hydrodynamical analysis of this system showed that they are compatible with a companion that is able to produce the large cavity and other observed features. <P />Based on observations collected at the European Organisation for astronomical research in the southern emisphere under ESO programmes 095.C-0298, 096.C-0241, 097.C-0865 and 189.C-0209.The reduced images are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A+A/622/A96">http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A+A/622/A96</A> [less ▲]

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