A5032302846- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Calibration and Measurement Techniques
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- High-pressure geophysics and materials
- History and Developments in Astronomy
- Scientific Research and Discoveries
- Solar and Space Plasma Dynamics
- Astrophysical Phenomena and Observations
- Geophysics and Gravity Measurements
- Spectroscopy and Laser Applications
- Atmospheric Ozone and Climate
- Space Exploration and Technology
- Particle Detector Development and Performance
- Astronomical and nuclear sciences
- CCD and CMOS Imaging Sensors
- Pulsars and Gravitational Waves Research
- Molecular Spectroscopy and Structure
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
- Galaxies: Formation, Evolution, Phenomena
Keele University
2015-2024
Max Planck Institute for Astronomy
2019
Max Planck Society
2019
University of St Andrews
2013
KU Leuven
2010
Czech Academy of Sciences, Astronomical Institute
2006
Charles University
2006
Institute of Space Sciences
2006
Liverpool John Moores University
1999
University College London
1993-1994
The SuperWASP cameras are wide‐field imaging systems at the Observatorio del Roque de los Muchachos on island of La Palma in Canary Islands, and Sutherland Station South African Astronomical Observatory. Each instrument has a field view some 482 deg2 with an angular scale 13 7 pixel−1, is capable delivering photometry accuracy better than 1% for objects having V∼7.0–11.5. Lower quality data brighter V∼15.0 stored project archive. systems, while designed to monitor fields high cadence,...
Context. Several competing scenarios for planetary-system formation and evolution seek to explain how hot Jupiters came be so close their parent stars. Most planetary parameters evolve with time, making it hard distinguish between models. The obliquity of an orbit respect the stellar rotation axis is thought more stable than other such as eccentricity. planets, date, appear aligned axis; few misaligned planets far detected are massive (> 2MJ).
We report on the discovery of WASP-12b, a new transiting extrasolar planet with $R_{\rm pl}=1.79 \pm 0.09 R_J$ and $M_{\rm pl}=1.41 0.1 M_J$. The host star properties were derived from Monte Carlo Markov Chain analysis transit photometry radial velocity data. Furthermore, by comparing stellar spectrum theoretical spectra evolution models, we determined that is super-solar metallicity ([M/H]$=0.3^{+0.05}_{-0.15}$), late-F (T$_{\rm eff}=6300^{+200}_{-100}$ K) which evolving off zero age main...
The WASP (Wide Angle Search for Planets) project is an exoplanet transit survey that has been automatically taking wide field images since 2004. Two instruments, one in La Palma and the other South Africa, continually monitor night sky, building up light curves of millions unique objects. These are used to search characteristics exoplanetary transits. This first public data release (DR1) archive makes available all curve from 2004 2008 both Northern Southern hemispheres. A web interface...
We have detected low-amplitude radial-velocity variations in two stars, USNO-B1.0 1219-0005465 (GSC 02265-00107 = WASP-1) and 0964-0543604 00522-01199 WASP-2). Both stars were identified as being likely host of transiting exoplanets the 2004 SuperWASP wide-field transit survey. Using newly-commissioned spectrograph SOPHIE at Observatoire de Haute-Provence, we found that both objects exhibit reflex orbital with amplitudes characteristic planetary-mass companions in-phase photometric orbits....
We present a detailed spectroscopic study of 93 solar-type stars that are targets the NASA/Kepler mission and provide chemical composition each target. find overall metallicity is well-represented by Fe lines. Relative abundances light elements (CNO) alpha-elements generally higher for low-metallicity stars. Our analysis benefits from accurately measured surface gravity asteroseismic Kepler curves. The log g parameter known to better than 0.03 dex held fixed in analysis. compare our Teff...
The Rossiter-McLaughlin effect observed for transiting exoplanets often requires prior knowledge of the stellar projected equatorial rotational velocity. This is usually provided by measuring broadening spectral lines, however this method has uncertainties as lines are also broadened velocity fields in photosphere known macroturbulence. We have estimated accurate values from asteroseismic analyses main sequence stars Kepler. frequency splittings detected solar-like oscillations these...
We derive absolute dimensions of the early B-type detached eclipsing binary V453 Cygni (B0.4 IV + B0.7 IV, P=3.89d), a member open cluster NGC 6871. From analysis new, high-resolution, spectroscopy and UBV light curves Cohen (1974) we find masses to be 14.36 +/- 0.20 11.11 0.13 Msun, radii 8.55 0.06 5.49 Rsun, effective temperatures 26600 500 25 800 K for primary secondary stars, respectively. The surface gravities 3.731 0.012 4.005 0.015 indicate that Cyg is reaching end its main sequence...
We report the discovery of WASP-3b, third transiting exoplanet to be discovered by WASP and SOPHIE collaboration. WASP-3b transits its host star USNO-B1.0 1256−0285133 every 1.846 834 ± 0.000 002 d. Our high-precision radial velocity measurements present a variation with amplitude characteristic planetary-mass companion in phase light curve. Adaptive optics imaging shows no evidence for nearby stellar companions, line-bisector analysis excludes faint, unresolved binarity activity as cause...
We combine results from interferometry, asteroseismology and spectroscopy to determine accurate fundamental parameters of 23 bright solar-type stars, spectral type F5 K2 luminosity classes III–V. For some stars we can use direct techniques the mass, radius, effective temperature, compare with indirect methods that rely on photometric calibrations or spectroscopic analyses. asteroseismic information available in literature infer an mass accuracy 4–15 per cent. From radius 3 find evidence...
Most of our knowledge extrasolar planets rests on precise radial-velocity measurements, either for direct detection or confirmation the planetary origin photometric transit signals. This has limited exploration parameter space exoplanet hosts to solar- and later-type, sharp-lined stars. Here we extend realm stars with known companions include hot, fast-rotating Planet-like transits have previously been reported in light curve obtained by SuperWASP survey A5 star HD 15082 (WASP–33; V= 8.3, v...
The Kepler spacecraft is providing time series of photometric data with micromagnitude precision for hundreds A-F type stars. We present a first general characterization the pulsational behaviour stars as observed in light curves sample 750 candidate propose three main groups to describe variety pulsating stars: gamma Dor, delta Sct, and hybrid assign 63% our one groups, identify remaining part rotationally modulated/active stars, binaries, different spectral type, or that show no clear...
We report the discovery of transiting giant planet WASP-17b, least-dense currently known. It is 1.6 Saturn masses but 1.5-2 Jupiter radii, giving a density 6-14 per cent that Jupiter. WASP-17b in 3.7-day orbit around sub-solar metallicity, V = 11.6, F6 star. Preliminary detection Rossiter-McLaughlin effect suggests retrograde (lambda ~ -150 deg), indicative violent history involving planet-planet or star-planet scattering. WASP-17b's bloated radius could be due to tidal heating resulting...
We report on the discovery of a new extremely short period transiting extrasolar planet, WASP-19b. The planet has mass Mpl = 1.15 ± 0.08 MJ, radius Rpl 1.31 0.06 RJ, and orbital P 0.7888399 0.0000008 days. Through spectroscopic analysis, we determine host star to be slightly super-solar metallicity ([M/H] 0.1 dex) G-dwarf with Teff 5500 100 K. In addition, detect periodic, sinusoidal flux variations in light curve which are used derive rotation for Prot 10.5 0.2 relatively stellar suggests...
We present the discovery by WASP-South survey, in close collaboration with Euler and TRAPPIST telescopes, of WASP-121 b, a new remarkable short-period transiting hot Jupiter, whose planetary nature has been statistically validated PASTIS software. The planet mass $1.183_{-0.062}^{+0.064}$ $M_{\mathrm{Jup}}$, radius 1.865 $\pm$ 0.044 $R_{\mathrm{Jup}}$, transits every $1.2749255_{-0.0000025}^{+0.0000020}$ days an active F6-type main-sequence star ($V$=10.4, $1.353_{-0.079}^{+0.080}$...
The gaseous giant planets WASP-4b and WASP-5b are transiting 12-magnitude solar-type stars in the Southern hemisphere. aim of present work is to refine parameters these systems using high cadence VLT/FORS2 <i>z<i/>-band transit photometry high-resolution VLT/UVES spectroscopy. For WASP-4, new estimates for planet radius mass from a combined analysis our VLT data with previously published radial velocities <i>R<i/><sub><i>J<i/><sub/> <i>M<i/><sub><i>J<i/><sub/>, resulting density . host star...
We present seven new transiting hot Jupiters from the WASP-South survey. The planets are all typical orbiting stars F4 to K0 with magnitudes of V = 10.3 12.5. orbital periods in range 3.9--4.6 d, planetary masses 0.4--2.3 Mjup and radii 1.1--1.4 Mjup. In line known Jupiters, densities Jupiter-like inflated (rho 0.13--1.07 rho_jup). use increasing numbers investigate distribution their 3--4-d "pile-up".
We report the discovery of WASP-4b, a large transiting gas-giant planet with an orbital period 1.34 days. This is first to be discovered by SuperWASP-South observatory and CORALIE collaboration orbiting star brighter than 16th magnitude in southern hemisphere. A simultaneous fit high-quality light curves precision radial velocity measurements leads planetary mass 1.22+ 0.09−0.08 MJup radius 1.42+ 0.07−0.04 RJup. The host USNO-B1.0 0479–0948995, G7 V visual 12.5. As result short period,...
We report the discovery of <i>WASP-8b<i/>, a transiting planet <i>2.25<i/> <i>±<i/> 0.08 <i>M<i/><sub>Jup<sub/> on strongly inclined eccentric 8.15-day orbit, moving in retrograde direction to rotation its late-G host star. Evidence is found that star multiple stellar system with two other companions. The dynamical complexity indicates it may have experienced secular interactions such as Kozai mechanism or formation differs from "classical" disc-migration theory.
The nearly continuous light curves with micromagnitude precision provided by the space mission Kepler are revolutionising our view of pulsating stars. They have revealed a vast sea low-amplitude pulsation modes that were undetectable from Earth. long time base allows an accurate determination frequencies and amplitudes needed for in-depth asteroseismic modeling. However, study to be successful, first estimates stellar parameters need known they can not derived photometry itself. Input...