A5069951612- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- History and Developments in Astronomy
- Astrophysical Phenomena and Observations
- Space Exploration and Technology
- Calibration and Measurement Techniques
- Inertial Sensor and Navigation
- Solar and Space Plasma Dynamics
- Scientific Research and Discoveries
- High-pressure geophysics and materials
- Climate variability and models
- Galaxies: Formation, Evolution, Phenomena
- Atmospheric Ozone and Climate
- Meteorological Phenomena and Simulations
- Infrared Target Detection Methodologies
- Nuclear physics research studies
- Geophysics and Gravity Measurements
- Sesquiterpenes and Asteraceae Studies
- nanoparticles nucleation surface interactions
- Economic and Technological Innovation
Hobart and William Smith Colleges
2015-2024
Cornell University
2023-2024
Max Planck Institute for Astronomy
2019
Max Planck Society
2019
University of Washington
2013-2017
Vanderbilt University
2009-2013
University of St Andrews
2006-2011
Queen's University Belfast
2011
University of Leicester
2011
Scottish Universities Physics Alliance
2009
The size of a planet is an observable property directly connected to the physics its formation and evolution. We used precise radius measurements from California-Kepler Survey (CKS) study distribution 2025 $\textit{Kepler}$ planets in fine detail. detect factor $\geq$2 deficit occurrence rate at 1.5-2.0 R$_{\oplus}$. This gap splits population close-in ($P$ < 100 d) small into two regimes: R$_P$ 1.5 R$_{\oplus}$ = 2.0-3.0 R$_{\oplus}$, with few between. Planets these regimes have nearly same...
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...
HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not.The documents may come from teaching institutions in France abroad, public private centers.L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de scientifiques niveau recherche, publiés ou non, émanant des établissements d'enseignement recherche français étrangers, laboratoires publics privés.
We have established precise planet radii, semimajor axes, incident stellar fluxes, and masses for 909 planets in 355 multi-planet systems discovered by Kepler. In this sample, we find that within a single system correlated sizes: each is more likely to be the size of its neighbor than drawn at random from distribution observed sizes. with three or planets, tend regular spacing: orbital period ratios adjacent pairs are correlated. Furthermore, smaller suggesting patterns sizes spacing linked...
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 the discovery of KELT-1b, first transiting low-mass companion from wide-field Kilodegree Extremely Little Telescope-North (KELT-North) survey. The V=10.7 primary is a mildly evolved, solar-metallicity, mid-F star. brown dwarf or super-massive planet with mass 27.23+/-0.50 MJ and radius 1.110+0.037-0.024 RJ, on very short period (P=1.21750007) circular orbit. KELT-1b receives large amount stellar insolation, an equilibrium temperature assuming zero albedo perfect redistribution...
We present the characterization of star KOI 961, an M dwarf with transit signals indicative three short-period exoplanets, originally discovered by Kepler Mission. proceed comparing 961 to Barnard's Star, a nearby, well-characterized mid-M dwarf. By colors, optical and near-infrared spectra, we find remarkable agreement between two, implying similar effective temperatures metallicities. Both are metal-poor compared Solar neighborhood, have low projected rotational velocity, high absolute...
Abstract We present the optical spectroscopic evolution of SN 2023ixf seen in subnight cadence spectra from 1.18 to 15 days after explosion. identify high-ionization emission features, signatures interaction with material surrounding progenitor star, that fade over first 7 days, rapid between observed within same night. compare lines and their relative strength those other supernovae early interaction, finding a close match 2020pni 2017ahn spectrum 2014G at later epochs. To physically...
In this Letter, we announce the discovery of a new dwarf galaxy, Leo T, in Local Group. It was found as stellar overdensity Sloan Digital Sky Survey Data Release 5 (SDSS DR5). The color-magnitude diagram T shows two well-defined features, which interpret red giant branch and sequence young, massive stars. As judged from fits to diagram, it lies at distance about 420 kpc has an intermediate-age population with metallicity [Fe/H]= -1.6, together young blue stars age 200 Myr. There is compact...
We present near-UV transmission spectroscopy of the highly irradiated transiting exoplanet WASP-12b, obtained with Cosmic Origins Spectrograph on Hubble Space Telescope. The spectra cover three distinct wavelength ranges: NUVA (2539-2580 {\AA}), NUVB (2655-2696 and NUVC (2770-2811 {\AA}). Three independent methods all reveal enhanced transit depths attributable to absorption by resonance lines metals in exosphere WASP-12b. Light curves total counts ranges show a detection at 2.5{\sigma}...
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...
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...
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...
Extended gas clouds have been previously detected surrounding the brightest known close-in transiting hot Jupiter exoplanets, HD 209458 b and 189733 b; we observed distant but more extreme system, WASP-12, with Hubble Space Telescope (HST). Near-UV (NUV) transits up to three times deeper than optical transit of WASP-12 reveal extensive diffuse gas, extending well beyond Roche lobe. The distribution absorbing varies between visits. deepest NUV are at wavelength ranges strong stellar...
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 twenty-three transit light curves and seven occultation for the ultra-short period planet WASP-43 b, in addition to eight new measurements of radial velocity star. Thanks this extensive data set, we improve significantly parameters system. Notably, largely improved precision on stellar density (2.41+-0.08 rho_sun) combined with constraining age be younger than a Hubble time allows us break degeneracy solution mentioned discovery paper. The resulting mass size are 0.717+-0.025...
We analyzed Kepler short-cadence M dwarf observations. Spectra from the ARC 3.5m telescope identify magnetically active (H$α$ in emission) stars. The stars are of mid-M spectral type, have numerous flares, and well-defined rotational modulation due to starspots. inactive early-M exhibit less starspot signature, fewer flares. A U-band energy scaling allows comparison flare frequency distributions with previous ground-based data. dwarfs span a large range energy, blurring distinction between...
We present the results of photometric surveys for stellar rotation in Hyades and Praesepe, using data obtained as part SuperWASP exoplanetary transit-search programme. determined accurate periods more than 120 sources whose cluster membership was confirmed by common proper motion colour–magnitude fits to clusters' isochrones. This allowed us determine effect magnetic braking on a wide range spectral types expected ages ∼600 Myr Praesepe. Both clusters show tight nearly linear relation...
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 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,...