Last 7 days     Results 2301-2320 of 47636.   111 112 113 114 115 116 117 118 119 120 121   The far-ultraviolet main auroral emission at Jupiter – Part 1: Dawn–dusk brightness asymmetriesBonfond, Bertrand ; Gustin, Jacques ; Gérard, Jean-Claude et alin Annales Geophysicae (2015), 33The main auroral emission at Jupiter generally appears as a quasi-closed curtain centered around the magnetic pole. This auroral feature, which accounts for approximately half of the total power emitted ... [more ▼]The main auroral emission at Jupiter generally appears as a quasi-closed curtain centered around the magnetic pole. This auroral feature, which accounts for approximately half of the total power emitted by the aurorae in the ultraviolet range, is related to corotation enforcement currents in the middle magnetosphere. Early models for these currents assumed axisymmetry, but significant local time variability is obvious on any image of the Jovian aurorae. Here we use far-UV images from the Hubble Space Telescope to further characterize these variations on a statistical basis. We show that the dusk side sector is ~ 3 times brighter than the dawn side in the southern hemisphere and ~ 1.1 brighter in the northern hemisphere, where the magnetic anomaly complicates the interpretation of the measurements. We suggest that such an asymmetry between the dawn and the dusk sectors could be the result of a partial ring current in the nightside magnetosphere. [less ▲]Detailed reference viewed: 39 (13 ULg) Kepler's first view of O-star variability: K2 data of five O stars in Campaign 0 as a proof of concept for O-star asteroseismologyBuysschaert, B.; Aerts, C.; Bloemen, S. et alin Monthly Notices of the Royal Astronomical Society (2015), 453We present high-precision photometric light curves of five O-type stars observed with the refurbished Kepler satellite during its Campaign 0. For one of the stars, we also assembled high-resolution ground ... [more ▼]We present high-precision photometric light curves of five O-type stars observed with the refurbished Kepler satellite during its Campaign 0. For one of the stars, we also assembled high-resolution ground-based spectroscopy with the HERMES spectrograph attached to the 1.2 m Mercator telescope. The stars EPIC 202060097 (O9.5V) and EPIC 202060098 (O7V) exhibit monoperiodic variability due to rotational modulation with an amplitude of 5.6 and 9.3 mmag and a rotation period of 2.63 and 5.03 d, respectively. EPIC 202060091 (O9V) and EPIC 202060093 (O9V:pe) reveal variability at low frequency but the cause is unclear. EPIC 202060092 (O9V:p) is discovered to be a spectroscopic binary with at least one multiperiodic β Cep-type pulsator whose detected mode frequencies occur in the range [0.11, 6.99] d[SUP]-1[/SUP] and have amplitudes between 0.8 and 2.0 mmag. Its pulsation spectrum is shown to be fully compatible with the ones predicted by core-hydrogen burning O-star models. Despite the short duration of some 33 d and the limited data quality with a precision near 100 μmag of these first K2 data, the diversity of possible causes for O-star variability already revealed from campaigns of similar duration by the MOST and CoRoT satellites is confirmed with Kepler. We provide an overview of O-star space photometry and give arguments why future K2 monitoring during Campaigns 11 and 13 at short cadence, accompanied by time-resolved high-precision high-resolution spectroscopy, opens up the possibility of in-depth O-star seismology. [less ▲]Detailed reference viewed: 19 (6 ULg) KIC 4768731: a bright long-period roAp star in the Kepler fieldSmalley, B.; Niemczura, E.; Murphy, S. J. et alin Monthly Notices of the Royal Astronomical Society (2015), 452We report the identification of 61.45 d[SUP]-1[/SUP] (711.2 μHz) oscillations, with amplitudes of 62.6 μmag, in KIC 4768731 (HD 225914) using Kepler photometry. This relatively bright (V = 9.17 ... [more ▼]We report the identification of 61.45 d[SUP]-1[/SUP] (711.2 μHz) oscillations, with amplitudes of 62.6 μmag, in KIC 4768731 (HD 225914) using Kepler photometry. This relatively bright (V = 9.17) chemically peculiar star with spectral type A5 Vp SrCr(Eu) has previously been found to exhibit rotational modulation with a period of 5.21 d. Fourier analysis reveals a simple dipole pulsator with an amplitude that has remained stable over a 4-yr time span, but with a frequency that is variable. Analysis of high-resolution spectra yields stellar parameters of T[SUB]eff[/SUB] = 8100 ± 200 K, log g = 4.0 ± 0.2, [Fe/H] = +0.31 ± 0.24 and v sin i = 14.8 ± 1.6 km s[SUP]-1[/SUP]. Line profile variations caused by rotation are also evident. Lines of Sr, Cr, Eu, Mg and Si are strongest when the star is brightest, while Y and Ba vary in antiphase with the other elements. The abundances of rare earth elements are only modestly enhanced compared to other roAp stars of similar T[SUB]eff[/SUB] and log g. Radial velocities in the literature suggest a significant change over the past 30 yr, but the radial velocities presented here show no significant change over a period of 4 yr. [less ▲]Detailed reference viewed: 8 (0 ULg) Chronos and Topos: The Inheritance of the Here-Now in Gail Jones’s Five BellsBelleflamme, Valérie-Anne Conference (2015, October 01)In an interview, Australian novelist, essayist, and academic Gail Jones claimed an interest in psycho-geography, i.e. “in the idea,” as she puts it, “that we must walk around our own place with an active ... [more ▼]In an interview, Australian novelist, essayist, and academic Gail Jones claimed an interest in psycho-geography, i.e. “in the idea,” as she puts it, “that we must walk around our own place with an active intelligence and with a degree of radical attention to what is there.” Taking Sydney as an example, Jones insists on the importance of looking at the city’s “shapes, its motions,” of attending to its “sounds, corridors between spaces, the unexpected.” It is, she continues, “about apprehending things through shapes and signs.” Sydney, to her, is a place haunted by its colonial inheritance, and Australia, more generally, is a “colony of trauma”, a place where “there is always a tension between remembering and forgetting.” Thus time and space are merged, or to put it as Jones does, “within the material spaces of a city are these immaterial traces of something else.” Along the same lines, Jones distinguishes between a vertical and a horizontal history: on the one hand, she explains, “there is the history that seems to be unfolding and moving forward,” while on the other hand there is a “plunging down into the interiority of the place, into its lost history.” This merging together of time and space, of history and geography is an inherent attribute of cosmopolitanism as it finds an echo in Jones’s novel Five Bells, which takes place on a single day in cosmopolitan Sydney and draws together four characters with their different national backgrounds, haunting histories and memories, all converging on Circular Quay, an Aboriginal site also marked as the place where Captain Cook first set foot. Focusing on the characters’ migrant perceptions of this historical and iconic site, my paper will seek to investigate how Jones draws on the trope of temporal and spatial inheritance in Five Bells to offer “ethical understanding” as an alternative to today’s embattled conception of Australian national identity. [less ▲]Detailed reference viewed: 18 (6 ULg) Impact of metabolic engineering strategies on phenotypic heterogeneityBrognaux, Alison ; Delepierre, Anissa ; Baert, Jonathan et alConference (2015, October 01)Detailed reference viewed: 15 (4 ULg) Prediction of Allogeneic Hematopoietic Stem-Cell Transplantation Mortality 100 Days After Transplantation Using a Machine Learning Algorithm: A European Group for Blood and Marrow Transplantation Acute Leukemia Working Party Retrospective Data Mining StudySHOUVAL, Roni; LABOPIN, Myriam; BONDI, Ori et alin Journal of Clinical Oncology (2015), 33(28), 3144-3152Purpose: Allogeneic hematopoietic stem-cell transplantation (HSCT) is potentiallu curative for acute leukemia (AL), but carries considerable risk. Machine learning algorithms, which are part of the data ... [more ▼]Purpose: Allogeneic hematopoietic stem-cell transplantation (HSCT) is potentiallu curative for acute leukemia (AL), but carries considerable risk. Machine learning algorithms, which are part of the data mining (DM) approach, may serve for transplantation-related mortality risk prediction. Patients and Methods: This work is a retrospective DM study on a cohort of 28,236 adult HSCT recipients from the AL registry of the European Group for Blood and Marrow Transplantation. The primary objective was prediction of overall mortality (OM) at 100 days after HSCT. Secondary objectives were estimation of nonrelapse mortality, leukemia-free survival, and overall survival at 2 years. Donor, recipient, and procedural characteristics were alalyzed. The alternating decision tree machine learning algorithm was applied for model development on 70 % of the data set and validated on the remaining data. [less ▲]Detailed reference viewed: 16 (1 ULg) DGTs, a complementary tool towards more efficient biomonitoring practicesRichir, Jonathan ; Lepoint, Gilles ; Donnay, Annick et alConference (2015, October 01)Among the diversity of contaminants, trace elements (TEs) remain of concern because of their persistence, their ability to accumulate in biota and their toxicity. The direct measurement of their dissolved ... [more ▼]Among the diversity of contaminants, trace elements (TEs) remain of concern because of their persistence, their ability to accumulate in biota and their toxicity. The direct measurement of their dissolved concentrations only gives punctual and fluctuating information, and often remains below detection limits of analytical methods. The more appropriate use of sentinel organisms, or bioindicators, to monitor TEs has thus often been preferred in environmental surveys. The introduction of the diffusive gradients in thin films (DGTs) technique has however participated to progressively change this binary view - bioindicator vs water - of the coastal monitoring of TEs, and DGTs rapidly became a relevant complementary tool to bioindicators, has illustrated below. In the framework of the STARECAPMED project, the ecology and the ecotoxicology of TEs were studied in the seagrass Posidonia oceanica (L.) Delile and the mussel Mytilus galloprovincialis Lamarck, 1819. DGTs (free- and pore-water probes) were deployed before sampling of organisms. TEs were also analyzed in suspended matter (dissolved and suspended-particulate TE speciation). Studies were performed in the Calvi Bay (Corsica, France), northwestern Mediterranean. TE concentrations in organisms and suspended matter or in DGT resins were measured by DRC-ICP-MS after HNO3/H202 mineralization or after a 24h elution in HNO3 1M, respectively. (1) TE bioaccumulation was first seasonally studied in P. oceanica over 3 years. Dissolved TE concentrations monitored with DGTs were low to very low. TE bioaccumulation dynamics in P. oceanica could thus be linked to the natural physiological cycle of the plant, in clean environmental conditions. (2) To complement that field survey, isolated seagrasses were in situ contaminated with TEs at environmental relevant concentrations. Through the use of DGTs, TE uptake kinetics were modelled for seagrasses exposed to know bioavailable concentrations of contaminants, as were loss kinetics during the following depuration phase. The TE sequestration ability of a healthy P. oceanica meadow facing sudden trace metal contamination events could also be quantified. (3) The deployment of pore-water DGT probes in bare-sand or seagrass colonized sediments further showed that, through its stabilizing function of the seabed, P. oceanica maintained higher TE levels in the pore-water. P. oceanica meadows thus offer a significant “depuration-filtering” ecological service along highly anthropized Mediterranean coasts. M. galloprovincialis are widely used in large spatial scale coastal monitoring surveys. (4) The deployment of caged mussels together with DGTs showed that the little contaminated water body of the Calvi Bay was relatively homogenous. It also allowed to calculate TE bioaccumulation towards mussels in reference conditions, and to compare it to native mussel populations. (5) Finally, during a 5 months mussel caging survey, mussels and suspended matter were collected weekly to monthly, such as were deployed DGTs. The physiological status of mussels, the speciation of TEs between their dissolved and suspended-particulate phases, and their relative influence on TE bioaccumulation dynamics in mussels were investigated. In conclusion, these case studies properly demonstrate how DGT probes can be used as a relevant and complementary tool to bioindicators. Their concomitant use should therefore be privileged in monitoring surveys. [less ▲]Detailed reference viewed: 29 (2 ULg) La prise en charge interdisciplinaire des patients lithiasiques réduit-elle à long terme le taux de geste urologique pour récidive ?Castiglione, Vincent ; Pieroni, Laurence; Conort, Pierre et alPoster (2015, October 01)Certains patients lithiasiques sont hautement récidivants, malgré les progrès considérables en urologie et une prise en charge des facteurs de risque. Nous avons fait l’hypothèse qu’une prise en charge ... [more ▼]Certains patients lithiasiques sont hautement récidivants, malgré les progrès considérables en urologie et une prise en charge des facteurs de risque. Nous avons fait l’hypothèse qu’une prise en charge interdisciplinaire au long court dédiée au diagnostic du processus lithogène, à l’analyse des causes de récidive, et à la détermination d'objectifs chiffrés de prévention, réduirait le nombre de gestes chirurgicaux pour récidive lithiasique et améliorerait ainsi la qualité de vie des patients. [less ▲]Detailed reference viewed: 29 (8 ULg) The K2-ESPRINT Project I: Discovery of the Disintegrating Rocky Planet K2-22b with a Cometary Head and Leading TailSanchis-Ojeda, R.; Rappaport, S.; Pallé, E. et alin Astrophysical Journal (2015), 812(2), 112We present the discovery of a transiting exoplanet candidate in the K2 Field-1 with an orbital period of 9.1457 hr: K2-22b. The highly variable transit depths, ranging from ∼0% to 1.3%, are suggestive of ... [more ▼]We present the discovery of a transiting exoplanet candidate in the K2 Field-1 with an orbital period of 9.1457 hr: K2-22b. The highly variable transit depths, ranging from ∼0% to 1.3%, are suggestive of a planet that is disintegrating via the emission of dusty effluents. We characterize the host star as an M-dwarf with Teff ≃ 3800 K. We have obtained ground-based transit measurements with several 1-m class telescopes and with the GTC. These observations (1) improve the transit ephemeris; (2) confirm the variable nature of the transit depths; (3) indicate variations in the transit shapes; and (4) demonstrate clearly that at least on one occasion the transit depths were significantly wavelength dependent. The latter three effects tend to indicate extinction of starlight by dust rather than by any combination of solid bodies. The K2 observations yield a folded light curve with lower time resolution but with substantially better statistical precision compared with the ground-based observations. We detect a significant “bump” just after the transit egress, and a less significant bump just prior to transit ingress. We interpret these bumps in the context of a planet that is not only likely streaming a dust tail behind it, but also has a more prominent leading dust trail that precedes it. This effect is modeled in terms of dust grains that can escape to beyond the planet's Hill sphere and effectively undergo “Roche lobe overflow,” even though the planet's surface is likely underfilling its Roche lobe by a factor of 2. [less ▲]Detailed reference viewed: 34 (10 ULg) Evidence for two spatially separated UV continuum emitting regions in the Cloverleaf broad absorption line quasarSluse, Dominique ; Hutsemekers, Damien ; Anguita, T. et alin Astronomy and Astrophysics (2015), 582Testing the standard Shakura-Sunyaev model of accretion is a challenging task because the central region of quasars where accretion takes place is unresolved with telescopes. The analysis of microlensing ... [more ▼]Testing the standard Shakura-Sunyaev model of accretion is a challenging task because the central region of quasars where accretion takes place is unresolved with telescopes. The analysis of microlensing in gravitationally lensed quasars is one of the few techniques that can test this model, yielding to the measurement of the size and of temperature profile of the accretion disc. We present spectroscopic observations of the gravitationally lensed broad absorption line quasar H1413+117, which reveal partial microlensing of the continuum emission that appears to originate from two separated regions: a microlensed region, corresponding the compact accretion disc; and a non-microlensed region, more extended and contributing to at least 30% of the total UV-continuum flux. Because this extended continuum is occulted by the broad absorption line clouds, it is not associated with the host galaxy, but rather with light scattered in the neighbourhood of the central engine. We measure the amplitude of microlensing of the compact continuum over the rest-frame wavelength range 1000-7000 Å. Following a Bayesian scheme, we confront our measurements to microlensing simulations of an accretion disc with a temperature varying as T ∝ R[SUP]-1/ν[/SUP]. We find a most likely source half-light radius of R[SUB]1/2[/SUB] = 0.61 × 10[SUP]16[/SUP]cm (i.e., 0.002 pc) at 0.18 μm, and a most-likely index of ν = 0.4. The standard disc (ν = 4/3) model is not ruled out by our data, and is found within the 95% confidence interval associated with our measurements. We demonstrate that, for H1413+117, the existence of an extended continuum in addition to the disc emission only has a small impact on the inferred disc parameters, and is unlikely to solve the tension between the microlensing source size and standard disc sizes, as previously reported in the literature. Based on observations made with ESO Telescopes at the Paranal Observatory (Chile). ESO program ID: 386.B-0337.Appendices A and B are available in electronic form at http://www.aanda.org [less ▲]Detailed reference viewed: 12 (1 ULg) À quels dieux sacrifier et adresser des prières pour avoir de belles et abondantes récoltes ? Quelques réflexions sur les dieux karpophoroi et consorts.Lebreton, Sylvain Conference (2015, October 01)Detailed reference viewed: 14 (2 ULg) Single cell analysis of the activity of the electron transport chain : a promising way to assess the effect of metabolic engineering strategiesBaert, Jonathan ; Delepierre, Anissa ; Brognaux, Alison et alConference (2015, October 01)Detailed reference viewed: 3 (1 ULg) The Subaru Coronagraphic Extreme Adaptive Optics System: Enabling High-Contrast Imaging on Solar-System ScalesJovanovic, N.; Martinache, F.; Guyon, O. et alin Publications of the Astronomical Society of the Pacific (2015), 127The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument is a multipurpose high-contrast imaging platform designed for the discovery and detailed characterization of exoplanetary systems and ... [more ▼]The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument is a multipurpose high-contrast imaging platform designed for the discovery and detailed characterization of exoplanetary systems and serves as a testbed for high-contrast imaging technologies for ELTs. It is a multiband instrument which makes use of light from 600 to 2500 nm, allowing for coronagraphic direct exoplanet imaging of the inner 3λ/D from the stellar host. Wavefront sensing and control are key to the operation of SCExAO. A partial correction of low-order modes is provided by Subaru's facility adaptive optics system with the final correction, including high-order modes, implemented downstream by a combination of a visible pyramid wavefront sensor and a 2000-element deformable mirror. The well-corrected NIR (y-K bands) wavefronts can then be injected into any of the available coronagraphs, including but not limited to the phase-induced amplitude apodization and the vector vortex coronagraphs, both of which offer an inner working angle as low as 1λ/D. Noncommon path, low-order aberrations are sensed with a coronagraphic low-order wavefront sensor in the infrared (IR). Low noise, high frame rate NIR detectors allow for active speckle nulling and coherent differential imaging, while the HAWAII 2RG detector in the HiCIAO imager and/or the CHARIS integral field spectrograph (from mid-2016) can take deeper exposures and/or perform angular, spectral, and polarimetric differential imaging. Science in the visible is provided by two interferometric modules: VAMPIRES and FIRST, which enable subdiffraction limited imaging in the visible region with polarimetric and spectroscopic capabilities respectively. We describe the instrument in detail and present preliminary results both on-sky and in the laboratory. [less ▲]Detailed reference viewed: 8 (1 ULg) Transcriptionally active HPV infection in the cervical squamo-columnar junctionHerfs, Michael Conference (2015, October 01)Detailed reference viewed: 16 (2 ULg) Halomethyl-cobalt(bis-acetylacetonate) for the controlled synthesis of functional polymersDemarteau, Jérémy ; Kermagoret, Anthony; German, Ian et alin Chemical Communications (2015), 51(76), 14334-14337Novel organocobalt complexes featuring weak C–CoL2 bonds (L = acetylacetonate) are prepared and used as sources of halomethyl radicals. They permit the precision synthesis of a-halide functionalized and ... [more ▼]Novel organocobalt complexes featuring weak C–CoL2 bonds (L = acetylacetonate) are prepared and used as sources of halomethyl radicals. They permit the precision synthesis of a-halide functionalized and telechelic polymers in organic media or in water. Substitution of halide by azide allows derivatization of polymers using the CuAAC click reaction. [less ▲]Detailed reference viewed: 45 (20 ULg) Synthèse du débat politique. Journée de réflexion au Sénat de Belgique: «Démocratie représentative : vers la fin d’un modèle ? Diagnostic et remèdes»Verjans, Pierre in Compte-rendu du Sénat de Belgique (2015, October 01)Les réflexions des responsables politiques en réaction aux interventions des scientifiques peuvent être interprétées en fonction de grille d'analyse de science politique, notamment celle d'Amartya Sen et ... [more ▼]Les réflexions des responsables politiques en réaction aux interventions des scientifiques peuvent être interprétées en fonction de grille d'analyse de science politique, notamment celle d'Amartya Sen et celle de Bernard Manin. [less ▲]Detailed reference viewed: 25 (2 ULg) Long-term activity and outburst of comet C/2013 A1 (Siding Spring) from narrow-band photometry and long-slit spectroscopyOpitom, Cyrielle ; Guilbert-Lepoutre, A.; Jehin, Emmanuel et alE-print/Working paper (2015)In this paper, we present a unique data set of more than one year's worth of regular observations of comet C/2013 A1(Siding Spring) with TRAPPIST in Chile, along with low-resolution spectra obtained with ... [more ▼]In this paper, we present a unique data set of more than one year's worth of regular observations of comet C/2013 A1(Siding Spring) with TRAPPIST in Chile, along with low-resolution spectra obtained with the ESO/VLT FORS 2 instrument. The comet made a close approach to Mars on October 19, 2014 and was then observed by many space and ground-based telescopes. We followed the evolution of the OH, NH, CN, $\mathrm{C_3}$, and $\mathrm{C_2}$ production rates as well as the $Af\rho$ parameter as a proxy for the dust production. We detected an outburst two weeks after perihelion, with gas and dust production rates being multiplied by a factor five within a few days. By modelling the shape of the CN and $\mathrm{C_2}$ radial profiles, we determined that the outburst happened around on November 10 around 15:30 UT ($\pm$ 5h) and measured a gas ejection velocity of $1.1\pm0.2$ km/s. We used a thermal evolution model to reproduce the activity pattern and outburst. Our results are consistent with the progressive formation of a dust mantle explaining the shallow dependence of gas production rates, which may be partially blown off during the outburst. We studied the evolution of gas composition, using various ratios such as CN/OH, $\mathrm{C_2}$/OH, or $\mathrm{C_3}$/OH, which showed little or no variation with heliocentric distance including at the time of the outburst. This indicates a relative level of homogeneity of the nucleus composition. [less ▲]Detailed reference viewed: 14 (5 ULg) Characterization of the K2-19 Multiple-Transiting Planetary System via High-Dispersion Spectroscopy, AO Imaging, and Transit Timing VariationsNarita, Norio; Hirano, Teruyuki; Fukui, Akihiko et alE-print/Working paper (2015)K2-19 (EPIC201505350) is an interesting planetary system in which two transiting planets with radii ~ 7 $R_{Earth}$ (inner planet b) and ~ 4 $R_{Earth}$ (outer planet c) have orbits that are nearly in a 3 ... [more ▼]K2-19 (EPIC201505350) is an interesting planetary system in which two transiting planets with radii ~ 7 $R_{Earth}$ (inner planet b) and ~ 4 $R_{Earth}$ (outer planet c) have orbits that are nearly in a 3:2 mean-motion resonance. Here, we present results of ground-based follow-up observations for the K2-19 planetary system. We have performed high-dispersion spectroscopy and high-contrast adaptive-optics imaging of the host star with the HDS and HiCIAO on the Subaru 8.2m telescope. We find that the host star is relatively old (>8 Gyr) late G-type star ($T_{eff}$ ~ 5350 K, $M_s$ ~ 0.9 $M_{Sun}$, and $R_{s}$ ~ 0.9 $R_{Sun}$). We do not find any contaminating faint objects near the host star which could be responsible for (or dilute) the transit signals. We have also conducted transit follow-up photometry for the inner planet with KeplerCam on the FLWO 1.2m telescope, TRAPPISTCAM on the TRAPPIST 0.6m telescope, and MuSCAT on the OAO 1.88m telescope. We confirm the presence of transit-timing variations, as previously reported by Armstrong and coworkers. We model the observed transit-timing variations of the inner planet using the synodic chopping formulae given by Deck & Agol (2015). We find two statistically indistinguishable solutions for which the period ratios ($P_{c}/P_{b}$) are located slightly above and below the exact 3:2 commensurability. Despite the degeneracy, we derive the orbital period of the inner planet $P_b$ ~ 7.921 days and the mass of the outer planet $M_c$ ~ 20 $M_{Earth}$. Additional transit photometry (especially for the outer planet) as well as precise radial-velocity measurements would be helpful to break the degeneracy and to determine the mass of the inner planet. [less ▲]Detailed reference viewed: 15 (2 ULg) The HARPS search for southern extra-solar planets. XXXVIII. Bayesian re-analysis of three systems. New super-Earths, unconfirmed signals, and magnetic cyclesDíaz, R. F.; Ségransan, D.; Udry, S. et alE-print/Working paper (2015)We present the analysis of the entire HARPS observations of three stars that host planetary systems: HD1461, HD40307, and HD204313. The data set spans eight years and contains more than 200 nightly ... [more ▼]We present the analysis of the entire HARPS observations of three stars that host planetary systems: HD1461, HD40307, and HD204313. The data set spans eight years and contains more than 200 nightly averaged velocity measurements for each star. This means that it is sensitive to both long-period and low-mass planets and also to the effects induced by stellar activity cycles. We modelled the data using Keplerian functions that correspond to planetary candidates and included the short- and long-term effects of magnetic activity. A Bayesian approach was taken both for the data modelling, which allowed us to include information from activity proxies such as $\log{(R'_{\rm HK})}$ in the velocity modelling, and for the model selection, which permitted determining the number of significant signals in the system. The Bayesian model comparison overcomes the limitations inherent to the traditional periodogram analysis. We report an additional super-Earth planet in the HD1461 system. Four out of the six planets previously reported for HD40307 are confirmed and characterised. We discuss the remaining two proposed signals. In particular, we show that when the systematic uncertainty associated with the techniques for estimating model probabilities are taken into account, the current data are not conclusive concerning the existence of the habitable-zone candidate HD40307 g. We also fully characterise the Neptune-mass planet that orbits HD204313 in 34.9 days. [less ▲]Detailed reference viewed: 16 (0 ULg) New and updated convex shape models of asteroids based on optical data from a large collaboration networkHanuš, J.; Ďurech, J.; Oszkiewicz, D. A. et alE-print/Working paper (2015)Asteroid modeling efforts in the last decade resulted in a comprehensive dataset of almost 400 convex shape models and their rotation states. This amount already provided a deep insight into physical ... [more ▼]Asteroid modeling efforts in the last decade resulted in a comprehensive dataset of almost 400 convex shape models and their rotation states. This amount already provided a deep insight into physical properties of main-belt asteroids or large collisional families. We aim to increase the number of asteroid shape models and rotation states. Such results are an important input for various further studies such as analysis of asteroid physical properties in different populations, including smaller collisional families, thermophysical modeling, and scaling shape models by disk-resolved images, or stellar occultation data. This provides, in combination with known masses, bulk density estimates, but constrains also theoretical collisional and evolutional models of the Solar System. We use all available disk-integrated optical data (i.e., classical dense-in-time photometry obtained from public databases and through a large collaboration network as well as sparse-in-time individual measurements from a few sky surveys) as an input for the convex inversion method, and derive 3D shape models of asteroids, together with their rotation periods and orientations of rotation axes. The key ingredient is the support of more that one hundred observers who submit their optical data to publicly available databases. We present updated shape models for 36 asteroids, for which mass estimates are currently available in the literature or their masses will be most likely determined from their gravitational influence on smaller bodies, which orbital deflection will be observed by the ESA Gaia astrometric mission. This was achieved by using additional optical data from recent apparitions for the shape optimization. Moreover, we also present new shape model determinations for 250 asteroids, including 13 Hungarias and 3 near-Earth asteroids. [less ▲]Detailed reference viewed: 26 (5 ULg)