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See detailHigh-precision photometry by telescope defocusing - III. The transiting planetary system WASP-2 star
Southworth, John; Mancini, L.; Novati, S Calchi et al

in Monthly Notices of the Royal Astronomical Society (2010), 408

ABSTRACT We present high-precision photometry of three transits of the extrasolar planetary system WASP-2, obtained by defocusing the telescopes, and achieving scatters of between 0.42 and 0.73 mmag ... [more ▼]

ABSTRACT We present high-precision photometry of three transits of the extrasolar planetary system WASP-2, obtained by defocusing the telescopes, and achieving scatters of between 0.42 and 0.73 mmag versus the best-fitting model. These data are modelled using the JKTEBOP code, and taking into account the light from the recently discovered faint star close to the system. The physical properties of the WASP-2 system are derived using tabulated predictions from five different sets of stellar evolutionary models, allowing both statistical and systematic error bars to be specified. We find the mass and radius of the planet to be M[SUB]b[/SUB] = 0.846 +/- 0.055 +/- 0.023M[SUB]Jup[/SUB] and R[SUB]b[/SUB] = 1.043 +/- 0.029 +/- 0.015R[SUB]Jup[/SUB]. It has a low equilibrium temperature of 1281 +/- 21K, in agreement with a recent finding that it does not have an atmospheric temperature inversion. The first of our transit data sets has a scatter of only 0.42mmag with respect to the best-fitting light-curve model, which to our knowledge is a record for ground-based observations of a transiting extrasolar planetary system. Based on data collected by MiNDSTEp with the Danish 1.54-m telescope at the ESO La Silla Observatory. E-mail: jkt@astro.keele.ac.uk ‡ Royal Society University Research Fellow. [less ▲]

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See detailHigh-precision photometry by telescope defocusing - IV. Confirmation of the huge radius of WASP-17 b
Southworth, John; Hinse, T. C.; Dominik, M. et al

in Monthly Notices of the Royal Astronomical Society (2012), 426

We present photometric observations of four transits in the WASP-17 planetary system, obtained using telescope defocusing techniques and with scatters reaching 0.5 mmag per point. Our revised orbital ... [more ▼]

We present photometric observations of four transits in the WASP-17 planetary system, obtained using telescope defocusing techniques and with scatters reaching 0.5 mmag per point. Our revised orbital period is 4.0 ± 0.6 s longer than previous measurements, a difference of 6.6σ, and does not support the published detections of orbital eccentricity in this system. We model the light curves using the JKTEBOP code and calculate the physical properties of the system by recourse to five sets of theoretical stellar model predictions. The resulting planetary radius, R[SUB]b[/SUB] = 1.932 ± 0.052 ± 0.010 R[SUB]Jup[/SUB] (statistical and systematic errors, respectively), provides confirmation that WASP-17 b is the largest planet currently known. All 14 planets with radii measured to be greater than 1.6 R[SUB]Jup[/SUB] are found around comparatively hot (T[SUB]eff[/SUB] > 5900 K) and massive (M[SUB]A[/SUB] > 1.15 M[SUB]&sun;[/SUB]) stars. Chromospheric activity indicators are available for eight of these stars, and all imply a low activity level. The planets have small or zero orbital eccentricities, so tidal effects struggle to explain their large radii. The observed dearth of large planets around small stars may be natural but could also be due to observational biases against deep transits, if these are mistakenly labelled as false positives and so not followed up. Based on data collected by MiNDSTEp with the Danish 1.54-m telescope at the ESO La Silla Observatory.Royal Society University Research Fellow. [less ▲]

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See detailHigh-precision photometry by telescope defocusing - V. WASP-15 and WASP-16
Southworth, John; Mancini, L.; Browne, P. et al

in Monthly Notices of the Royal Astronomical Society (2013), 434

We present new photometric observations of WASP-15 and WASP-16, two transiting extrasolar planetary systems with measured orbital obliquities but without photometric follow-up since their discovery papers ... [more ▼]

We present new photometric observations of WASP-15 and WASP-16, two transiting extrasolar planetary systems with measured orbital obliquities but without photometric follow-up since their discovery papers. Our new data for WASP-15 comprise observations of one transit simultaneously in four optical passbands using GROND on the MPG/European Southern Observatory (ESO) 2.2 m telescope, plus coverage of half a transit from DFOSC on the Danish 1.54 m telescope, both at ESO La Silla. For WASP-16 we present observations of four complete transits, all from the Danish telescope. We use these new data to refine the measured physical properties and orbital ephemerides of the two systems. Whilst our results are close to the originally determined values for WASP-15, we find that the star and planet in the WASP-16 system are both larger and less massive than previously thought. [less ▲]

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See detailHigh-precision photometry by telescope defocussing - II. The transiting planetary system WASP-4
Southworth, John; Hinse, T. C.; Burgdorf, M. J. et al

in Monthly Notices of the Royal Astronomical Society (2009)

We present and analyse light curves of four transits of the Southern hemisphere extrasolar planetary system WASP-4, obtained with a telescope defocused so the radius of each point spread function was 17 ... [more ▼]

We present and analyse light curves of four transits of the Southern hemisphere extrasolar planetary system WASP-4, obtained with a telescope defocused so the radius of each point spread function was 17 arcsec (44 pixels). This approach minimizes both random and systematic errors, allowing us to achieve scatters of between 0.60 and 0.88 mmag per observation over complete transit events. The light curves are augmented by published observations and analysed using the JKTEBOP code. The results of this process are combined with theoretical stellar model predictions to derive the physical properties of the WASP-4 system. We find that the mass and radius of the planet are M[SUB]b[/SUB] = 1.289[SUP]+0.090[/SUP][SUB]-0.090[/SUB][SUP]+0.039[/SUP][SUB]-0.000[/SUB]M[SUB]Jup[/SUB] and R[SUB]b[/SUB] = 1.371[SUP]+0.032[/SUP][SUB]-0.035[/SUB][SUP]+0.021[/SUP][SUB]-0.000[/SUB]R[SUB]Jup[/SUB], respectively (statistical and systematic uncertainties). These quantities give a surface gravity and density of g[SUB]b[/SUB] = 17.03[SUP]+0.97[/SUP][SUB]-0.54[/SUB]ms[SUP]-2[/SUP] and rho[SUB]b[/SUB] = 0.500[SUP]+0.032[/SUP][SUB]-0.021[/SUB][SUP]+0.000[/SUP][SUB]-0.008[/SUB] rho[SUB]Jup[/SUB], and fit the trends for short-period extrasolar planets to have relatively high masses and surface gravities. WASP-4 is now one of the best-quantified transiting extrasolar planetary systems, and significant further progress requires improvements to our understanding of the physical properties of low-mass stars. Based on data collected by MiNDSTEp with the Danish 1.54m telescope at the ESO La Silla Observatory. E-mail: jkt@astro.keele.ac.uk â ¡ Royal Society University Research Fellow. [less ▲]

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See detailHigh-Precision Spectroscopy of Pulsating Stars
Aerts, C.; Hekker, S.; Desmet, M. et al

in Precision Spectroscopy in Astrophysics, Proceedings of the ESO/Lisbon/Aveiro Conference held in Aveiro, Portugal, 11-15 September 2006. (2008)

We review methodologies currently available to interprete time series of high-resolution high-S/N spectroscopic data of pulsating stars in terms of the kind of (non-radial) modes that are excited. We ... [more ▼]

We review methodologies currently available to interprete time series of high-resolution high-S/N spectroscopic data of pulsating stars in terms of the kind of (non-radial) modes that are excited. We illustrate the drastic improvement of the detection treshold of line-profile variability thanks to the advancement of the instrumentation over the past two decades. This has led to the opportunity to interprete line-profile variations with amplitudes of order m/s, which is a factor 1000 lower than the earliest line-profile time series studies allowed for. [less ▲]

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See detailHigh-pressure study of the beta-to-alpha transition in Ga2O3
Machon, D.; McMillan, P. F.; Xu, Bin ULg et al

in Physical Review. B, Condensed Matter and Materials Physics (2006), 73(9),

The high-pressure behavior of Ga2O3 is studied up to 40 GPa using synchrotron x-ray diffraction and Raman spectroscopy in diamond anvil cells. A phase transformation from the monoclinic beta-phase (C2/m ... [more ▼]

The high-pressure behavior of Ga2O3 is studied up to 40 GPa using synchrotron x-ray diffraction and Raman spectroscopy in diamond anvil cells. A phase transformation from the monoclinic beta-phase (C2/m) is observed at a pressure above 20-22 GPa. The high-pressure polymorph is identified as the alpha-phase that is isostructural with corundum (R (3) over barc symmetry) from the x-ray diffraction data. However, considerable anion disorder is indicated by the appearance of broad bands in the Raman spectra. The experimental results are complemented by ab initio theoretical calculations of the energetics of the two structures and the lattice dynamics. [less ▲]

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See detailHigh-quality remeshing using harmonic maps
Geuzaine, Christophe ULg; Marchandise, E.; Remacle, J.-F.

in Proceedings of the 5th Advanced Computational Electromagnetics workshop (2010, July)

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See detailHigh-Quality Remeshing using Harmonic Maps
Geuzaine, Christophe ULg

Scientific conference (2010, March 30)

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See detailHigh-Quality Surface Remeshing Using Harmonic Maps
Remacle, J.-F.; Geuzaine, Christophe ULg; Compère, G. et al

in International Journal for Numerical Methods in Engineering (2010), 83(4), 403-425

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See detailHigh-rate of multiple genital HPV infections detected by DNA hybridization
Lauricella-Lefèbvre, M. A.; Piette, Jacques ULg; Lifrange, Eric ULg et al

in Journal of Medical Virology (1992), 36(4), 265-270

Cervical smears collected from 450 patients involved in a clinical follow-up of cervical human papillomaviruses (HPV) infections were screened for the presence of HPV 6b, 11, 16, and 18 DNA by both dot ... [more ▼]

Cervical smears collected from 450 patients involved in a clinical follow-up of cervical human papillomaviruses (HPV) infections were screened for the presence of HPV 6b, 11, 16, and 18 DNA by both dot blot and southern blot hybridization methods. Using very high stringency hybridization assays, the four HPV types could be easily distinguished by dot blotting. After a preliminary clinical sorting, 42.9% of the samples were found to be HPV-positive. Among the samples infected by a single HPV, type 16 was the most frequent (25.4% of the positive samples) followed by 6b (19.7%), 11 (8.3%), and 18 (7.2%). Double or even multiple infections by the different HPV types were detected at a very high rate (39.4% of the positive samples). [less ▲]

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See detailHigh-resolution Climatology of the North-East Atlantic using Data-Interpolating Variational Analysis
Troupin, Charles ULg; Machín, Francisco; Ouberdous, Mohamed ULg et al

Conference (2009, April 21)

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See detailHigh-resolution Climatology of the northeast Atlantic using Data-Interpolating Variational Analysis (DIVA)
Troupin, Charles ULg; Machin, Francis; Ouberdous, Mohamed ULg et al

in Journal of Geophysical Research (2010), 115(C08005), 20

Numerous climatologies are available at different resolutions and cover various parts of the global ocean. Most of them have a resolution too low to represent suitably regional processes and the methods ... [more ▼]

Numerous climatologies are available at different resolutions and cover various parts of the global ocean. Most of them have a resolution too low to represent suitably regional processes and the methods for their construction are not able to take into account the influence of physical effects (topographic constraints, boundary conditions, advection, etc.). A high-resolution atlas for temperature and salinity is developed for the northeast Atlantic Ocean on 33 depth levels. The originality of this climatology is twofold: (1) For the data set, data are collected on all major databases and aggregated to lead to an original data collection without duplicates, richer than the World Ocean Database 2005, for the same region of interest. (2) For the method, climatological fields are constructed using the variational method Data-Interpolating Variational Analysis. The formulation of the latter allows the consideration of coastlines and bottom topography, and has a numerical cost almost independent on the number of observations. Moreover, only a few parameters, determined in an objective way, are necessary to perform an analysis. The results show overall good agreement with the widely used World Ocean Atlas, but also reveal significant improvements in coastal areas. Error maps are generated according to different theories and emphasize the importance of data coverage for the creation of such climatological fields. Automatic outlier detection is performed, and its effects on the analysis are examined. The method presented here is very general and not dependent on the region, hence it may be applied for creating other regional atlas in different zones of the global ocean. [less ▲]

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See detailHigh-resolution clutter-power estimation for range-dependence compensation in conformal-array STAP
Ries, Philippe; Lapierre, Fabian D.; Lesturgie, Marc et al

Conference (2008)

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See detailHigh-resolution diatom/clay record in Lake Baikal from grey scale, and magnetic susceptibility over Holocene and Termination I
Boes, Xavier; Piotrowska, Natalia; Fagel, Nathalie ULg

in Global and Planetary Change (2005), 46(1-4), 299-313

Tracing past climate signals from Lake Baikal sediments with a "multi-annual' resolution by conventional techniques is a difficult challenge since the sedimentation rates from Termination I up to the ... [more ▼]

Tracing past climate signals from Lake Baikal sediments with a "multi-annual' resolution by conventional techniques is a difficult challenge since the sedimentation rates from Termination I up to the present range from 0.004 to 0.17 mm/year. In this paper, climate signals are reconstructed from three continuous sediment records from Vydrino Shoulder and Posolsky Bank in the Southern Basin, and Continent Ridge in the Northern Basin. For each coring site, a calendar age model was constructed using calibrated radiocarbon ages. The magnetic susceptibility is used to better constrain the age models over OIS4 to OIS1 The cores have been hardened using polymerized technique in order to allow the easy cut of thin sections that contain evidence for narrow biogenic/clayey laminations. The grey scale taken from the thin sections is used here as a high-resolution proxy record of diatom/clay ratio. The grey density values are qualitatively interpreted against the sediment components by optical microscopy from the thin sections. In the Northern Basin, the Continent station provides the best age model and sediment resolution over the Termination I period. In particular, four optima (i.e. Bolling, Allerod, Atlantic, and Subboreal) are indicated by substantial increases of the grey scale, whereas cold periods like the Younger Dryas correspond to lower grey scale values. We emphasize that the short-term variations in the grey scale at 20 mu m resolution could correspond to short climate responses in Lake Baikal sediments. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailHigh-resolution epiluminescence colorimetry of striae distensae.
Hermanns, J.-F.; Pierard, Gérald ULg

in Journal of the European Academy of Dermatology & Venereology (2006), 20(3), 282-7

BACKGROUND: Colours of striae distensae are often different from that of the surrounding skin. A close look using dermoscopy discloses distinct patterns of melanized networks at these sites. The aim of ... [more ▼]

BACKGROUND: Colours of striae distensae are often different from that of the surrounding skin. A close look using dermoscopy discloses distinct patterns of melanized networks at these sites. The aim of the study was to design a method of high-\resolution analytical analysis of the skin colours using the combination of photographic dermoscopy and small field reflectance colorimetry. METHODS: Clinical photographs were taken from striae distensae and their surrounding skin using a Dermaphot (Heine Optotechnik, Hersching, Germany). A final magnification of 125x was obtained on paper photographs. The reflectance colorimeter Visi-Chroma VC-100 (Biophotonics, Lessines, Belgium) was used to measure colours of the pigmentary networks in the L*a*b* system. Differential colour parameters (deltaE*ab, deltaL*, deltaa*, deltab*) were calculated for each case between the lesional and the surrounding normal skin, and between the melanized reticulated pattern and the enclosed lighter areas. RESULTS: Objective colorimetric assessments distinguished four distinct types, namely striae albae, striae rubrae, striae caeruleae and striae nigrae. The latter peculiar hyperpigmented type of striae distensae was specifically identified by epiluminescence examination in dark-skinned subjects. The fine-melanized honeycomb network present on the adjacent intact skin was reshaped inside striae in a streaky pattern perpendicular to the striae axis. Strong linear correlations were found between all combinations of deltaL* and deltab* evaluating colours of the reticulated and the honeycomb alveolar patterns both inside and outside the striae distensae. By contrast, no correlations were found between deltaa* and the other colorimetric parameters. CONCLUSION: The direct and/or indirect influences of melanocyte mechanobiology appear to have a prominent effect on the various colours of striae distensae. [less ▲]

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See detailHigh-Resolution GC Coupled to High-Resolution MS in the Analysis of Dioxins and Related Substances, Principles and Applications
Eppe, Gauthier ULg; De Pauw, Edwin ULg; Focant, Jean-François ULg

in Niessen, W. M. A. (Ed.) The Encyclopedia of Mass Spectrometry, Volume 8, Hyphenated Methods (2006)

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See detailHigh-resolution gene maps of horse chromosomes 14 and 21: Additional insights into evolution and rearrangements of HSA5 homologs in mammals.
Goh, Glenda; Raudsepp, T; Durkin, Keith ULg et al

in Genomics (2007), 89

High-resolution physically ordered gene maps for equine homologs of human chromosome 5 (HSA5), viz., horse chromosomes 14 and 21 (ECA14 and ECA21), were generated by adding 179 new loci (131 gene-specific ... [more ▼]

High-resolution physically ordered gene maps for equine homologs of human chromosome 5 (HSA5), viz., horse chromosomes 14 and 21 (ECA14 and ECA21), were generated by adding 179 new loci (131 gene-specific and 48 microsatellites) to the existing maps of the two chromosomes. The loci were mapped primarily by genotyping on a 5000-rad horse × hamster radiation hybrid panel, of which 28 were mapped by fluorescence in situ hybridization. The approximately fivefold increase in the number of mapped markers on the two chromosomes improves the average resolution of the map to 1 marker/0.9 Mb. The improved resolution is vital for rapid chromosomal localization of traits of interest on these chromosomes and for facilitating candidate gene searches. The comparative gene mapping data on ECA14 and ECA21 finely align the chromosomes to sequence/gene maps of a range of evolutionarily distantly related species. It also demonstrates that compared to ECA14, the ECA21 segment corresponding to HSA5 is a more conserved region because of preserved gene order in a larger number of and more diverse species. Further, comparison of ECA14 and the distal three-quarters region of ECA21 with corresponding chromosomal segments in 50 species belonging to 11 mammalian orders provides a broad overview of the evolution of these segments in individual orders from the putative ancestral chromosomal configuration. Of particular interest is the identification and precise demarcation of equid/Perissodactyl-specific features that for the first time clearly distinguish the origins of ECA14 and ECA21 from similar-looking status in the Cetartiodactyls. [less ▲]

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See detailHigh-Resolution Limb Observations of Proton Aurora
Chua, D. H.; Dymond, K. F.; Budzien, S. A. et al

Conference (2003, December 01)

The interaction of precipitating protons in the upper atmosphere involves charge exchange, ionization, elastic and inelastic collisions, and the deposition of energy from the bottom of the F-region to the ... [more ▼]

The interaction of precipitating protons in the upper atmosphere involves charge exchange, ionization, elastic and inelastic collisions, and the deposition of energy from the bottom of the F-region to the D-region of the ionosphere. These processes and the transport of incident protons through this range of altitudes has been described through a variety of modeling techniques but there has been a dearth of altitude-resolved observations of proton precipitation with which to validate such models. We present new limb observations of Doppler-shifted Lyman-α proton aurora emissions obtained by the High-resolution Ionospheric and Thermospheric Spectrograph (HITS) aboard the Advanced Research and Global Observation Satellite (ARGOS) that fill this niche. HITS performs limb scans that include tangent altitudes between 90 km and 400 km with approximately 5 km vertical resolution. The Doppler shifts of the proton aurora Lyman-α emissions are measured with 1.5 Angstrom resolution and are used to infer mean energies of the incident protons as a function of altitude. Observed energy-range (dE/dz) relations are compared to those predicted by a Monte Carlo simulation of proton transport in the upper atmosphere. [less ▲]

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See detailHigh-resolution measurements and modelling of the Cape Ghir upwelling filament during the CAIBEX survey
Troupin, Charles ULg; Sangrà, Pablo; Arístegui, Javier et al

Poster (2010, April 26)

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