bluuebunny/crossref_metadata_2025_split huggingface dataset:
New transiting exoplanets from the SuperWASP-North survey
Authors: Faedi Francesca , Barros Susana C. C. , Pollacco Don , Simpson Elaine K. , McCormac James , Moulds Victoria , Watson Chris , Todd Ian , Keenan F. , Fitzsimmons Alan , Chew Yilen Gómez Maqueo ,   the WASP Consortium
Published: November 2011

AbstractThe Wide Angle Search for Planet (WASP) project is one of the leading projects in the discovery of transiting exoplanets. We present 1) the current status of the WASP-North survey, 2) our recent exoplanet discoveries, and 3) we exemplify how these results fit into our understanding of transiting exoplanet properties and how they can help to understand exoplanet diversity.
Composition of transiting and transiting-only super-Earths
Authors: Valencia Diana 
Published: November 2011

AbstractThe relatively recent detections of the first three transiting super-Earths mark the beginning of a subfield within exoplanets that is both fruitful and challenging. The first step into characterizing these objects is to infer their composition given the degenerate character of the problem. The calculations show that Kepler-10b has a composition between an Earth-like and a Mercury-like (enriched in iron) composition. In contrast, GJ 1214b is too large to be solid, and has to have a volatile envelope. Lastly, while three of the four reported mass estimates of CoRoT-7b allow for a rocky composition, one forbids it and can only be reconciled with significant amounts of water vapor. In addition to these three transiting low-mass planets, there are now more than one thousand Kepler planets with only measured radius. Even without a mass measurement (“transiting-only”) it is still possible to place constraints on the amount of volatile content of the highly-irradiated planets, as their envelopes, if present, are flared. Using Kepler-9d as an example, we estimate its water vapor, or hydrogen and helium content to be less than 50% or 0.1% by mass respectively.
The origin of retrograde hot Jupiters
Authors: Naoz Smadar , Farr Will M. , Lithwick Yoram , Rasio Frederic A. 
Published: November 2011

AbstractMany hot Jupiters are observed to be misaligned with respect to the rotation axis of the star (as measured through the Rossiter–McLaughlin effect) and some (about ~ 25%) even appear to be in retrograde orbits. We show that the presence of an additional, moderately inclined and eccentric massive planet in the system can naturally explain close, inclined, eccentric, and even retrograde orbits. We have derived a complete and accurate treatment of the secular dynamics including both the key octupole-order effects and tidal friction. The flow of angular momentum from the inner orbit to the orbit of the perturber can lead to both high eccentricities and inclinations, and even flip the inner orbit. In our treatment the component of the inner orbit's angular momentum perpendicular to the stellar equatorial plane can change sign; a brief excursion to very high eccentricity during the chaotic evolution of the inner orbit can then lead to rapid “tidal capture,” forming a retrograde hot Jupiter. Previous treatments of the secular dynamics focusing on stellar-mass perturbers would not allow for such an outcome, since in that limit the component of the inner orbit's angular momentum perpendicular to the stellar equatorial plane is strictly conserved. Thus, the inclination of the planet's orbit could not change from prograde to retrograde.
Evolution of spin direction of accreting magnetic protostars and spin-orbit misalignment in exoplanetary systems
Authors: Lai Dong , Foucart Francois , Lin Douglas N. C. 
Published: November 2011

AbstractRecent observations have shown that in many exoplanetary systems the spin axis of the parent star is misaligned with the planet's orbital axis. These have been used to argue against the scenario that short-period planets migrated to their present-day locations due to tidal interactions with their natal discs. However, this interpretation is based on the assumption that the spins of young stars are parallel to the rotation axes of protostellar discs around them. We show that the interaction between a magnetic star and its circumstellar disc can (although not always) have the effect of pushing the stellar spin axis away from the disc angular momentum axis toward the perpendicular state and even the retrograde state. Planets formed in the disc may therefore have their orbital axes misaligned with the stellar spin axis, even before any additional planet-planet scatterings or Kozai interactions take place. In general, magnetosphere–disc interactions lead to a broad distribution of the spin–orbit angles, with some systems aligned and other systems misaligned.
A roadmap towards habitable exoplanets by the Blue Dots Initiative
Authors: du Foresto V. Coudé ,   the Blue Dots participants
Published: November 2011

AbstractThis paper is an abridged version of the report produced by the Blue Dots initiative, whose activities include the elaboration of a roadmap towards the spectroscopic characterization of habitable exoplanets. The full version of the Blue Dots report can be downloaded at http://www.blue-dots.net/spip.php?article105. While the roadmap will need to be updated regularly, it is expected that the methodology developed within Blue Dots will provide a durable framework for the elaboration of future revisions.
The Gaia astrometric survey for exoplanets in the solar neighborhood
Authors: Busonero Deborah 
Published: November 2011

AbstractThe Gaia astrometric mission holds the promise for crucial contributions to almost every subject of astrophysics and astronomy, including planetary systems astrophysics. We focus on the potential of the Gaia mission as perfect tool for a complete screening of nearby stars in search for exoplanets. We build our dissertation on the most recent results of the satellites astrometric payload performances and data reduction capabilities. We put the identified capabilities in context by illustrating the outstanding contribution to planetary sciences, in combination with nowadays and next decade exoplanets search programs, as a complement to other indirect and direct methods for the detection and characterization of planetary systems. We conclude by highlighting the crucial improvements in the optimization of the target lists of future dedicated observatory projects.
How common are Earth-Moon planetary systems?
Authors: Elser Sebastian , Stadel Joachim , Moore Ben , Morishima Ryuji 
Published: November 2011

AbstractThe Earth's comparatively massive moon, formed via a giant impact on the proto-Earth, has played an important role in the development of life on our planet. Here we study how frequently Earth-Moon planetary systems occur. We derive limits on the collision parameters that may guarantee the formation of a circumplanetary disk after a protoplanet collision that could form a satellite. Based on a large set of simulations, we observe potential moon forming impacts and conclude that giant impacts with the required energy and orbital parameters for producing a binary planetary system occur frequently with more than one in ten terrestrial planets hosting a massive moon.
Long-term stability of the dead-zone in proto-planetary disks
Authors: Flock Mario , Turner Neal , Dzyurkevich Natalia , Klahr Hubert 
Published: November 2011

AbstractWe present 3D global non-ideal MHD simulations with a self consistent dynamic evolution of ionization fraction of the gas as result of reduced chemical network. We include X-ray ionization from the star as well as cosmic ray ionization. Based on local gas density and temperature in our chemical network, we determine the magnetic resistivity, which is fed back in MHD simulations. Parameters for dust size and abundance are chosen to have accreting layers and a laminar “dead” mid-plane.
High-contrast polarimetric imaging of the protoplanetary disk around AB Aurigae
Authors: Fukagawa M. , Wisniewski J. P. , Hashimoto J. , Okamoto Y. , Grady C. A. , Muto T. , Inutsuka S.-I. , Hodapp K. W. , Kudo T. , Momose M. , Shibai H. , Tamura M. ,   the SEEDS Team
Published: November 2011

AbstractWe present the spatially-resolved polarization measurements for the disk around the Herbig Ae star, AB Aurigae. The images were obtained in J, H, and Ks bands with the coronagraphic camera HiCIAO on the Subaru Telescope. The inner region beyond 30 AU from the star was imaged, which reveals an azimuthal dip, a radial gap at around 80 AU, and complex spiral-like emission in polarized light.
Volatiles and refratories in solar analogs: No terrestial planet connection
Authors: González Hernández Jonay I. , Israelian Garik , Santos Nuno C. , Sousa Sergio , Delgado-Mena Elisa , Neves Vasco , Udry Stéphane 
Published: November 2011

AbstractWe have analysed very high-quality HARPS and UVES spectra of 95 solar analogs, 24 hosting planets and 71 without detected planets, to search for any possible signature of terrestial planets in the chemical abundances of volatile and refractory elements with respect to the solar abundances.We demonstrate that stars with and without planets in this sample show similar mean abundance ratios, in particular, a sub-sample of 14 planet-host and 14 “single” solar analogs in the metallicity range 0.14 < [Fe/H] < 0.36. In addition, two of the planetary systems in this sub-sample, containing each of them a super-Earth-like planet with masses in the range ~ 7-11 Earth masses, have different volatile-to-refratory abundance ratios to what would be expected from the presence of a terrestial planets.Finally, we check that after removing the Galactic chemical evolution effects any possible difference in mean abundances, with respect to solar values, of refratory and volatile elements practically dissappears.
Forming short-period earth-like planets via a collision-merger scenario
Authors: Jin Sheng , Ji Jianghui , Tinney Chris G. 
Published: November 2011

AbstractWe present a new formation mechanism to produce short-period Earth-like planets in the late stage of planet formation, through a collision-merger scenario. In this scenario, a planetary embryo is directly thrown into a close-in orbit after a collision with another embryo, and then the larger merged body is seized by the central star as a hot Earth-like planet.
Exoplanet discovery and characterisation through robotic follow-up of microlensing events: Season 2010 results
Authors: Street Rachel A. , Tsapras Yiannis , Horne Keith , Snodgrass Colin , Bramich Daniel M. , Dominik Martin , Hawkins Eric , Browne Paul , Han Cheongho , Steele Iain , Dodds Peter , Liebig Christine 
Published: November 2011

AbstractMicrolensing searches for planets are sensitive to small, cold exoplanets from 1–6 AU from their host stars and therefore probe an important part of parameter space. Other techniques would require many years of observations, often from space, to detect similar systems. Microlensing events can be characterised from only ground-based observations over a relatively short (≤100d) timescales. LCOGT and SUPA/St Andrews are building a robotic global network of telescopes that will be well suited to follow these events. Here we present preliminary results of the Galactic Bulge observing season 2010 March–October.
Modeling giant planets and brown dwarfs
Authors: Becker Andreas , Nettelmann Nadine , Kramm Ulrike , Lorenzen Winfried , French Martin , Redmer Ronald 
Published: November 2011

AbstractWe present new results in modeling the interiors of Giant Planets (GP) and Brown Dwarfs (BD). In general models of the interior rely on equation of state data for planetary materials which have considerable uncertainties in the high-pressure domain. Our calculations are based on ab initio equation of state (EOS) data for hydrogen, helium, hydrogen-helium mixtures and water as the representative of all heavier elements or ices using finite-temperature density functional theory molecular dynamics (FT-DFT-MD) simulations. We compare results for the BD Gliese 229B calculated with Saumon-Chabrier-Van Horn EOS (SCVH95) and our EOS data.
A new look at NICMOS transmission spectroscopy: No conclusive evidence for molecular features
Authors: Gibson Neale P. , Pont Frederic , Aigrain Suzanne 
Published: November 2011

AbstractWe present a re-analysis of archival HST/NICMOS transmission spectroscopy of the exoplanet system, HD 189733, from which detections of several molecules have been claimed. As expected, we can replicate the transmission spectrum previously published when we use an identical model for the systematic effects, although the uncertainties are larger as we use a residual permutation algorithm in an effort to account for instrumental systematics. We also find that the transmission spectrum is considerably altered when slightly changing the instrument model, and conclude that the NICMOS transmission spectrum is too dependent on the method used to remove systematics to be considered a robust detection of molecular species, given that there is no physical reason to believe that the baseline flux should be modelled as a linear function of any chosen set of parameters.
Hot Jupiters and the evolution of stellar angular momentum
Authors: Damiani Cilia , Lanza Antonino F. 
Published: November 2011

AbstractA close-in massive planet affects the angular momentum of its host star through tidal and magnetic interactions. The transiting planets allow us to study the distribution of the spin and orbital angular momenta in star-planet systems. Considering a sample of about 70 systems, we find that stars having an effective temperature between 6000 and 6700 K and a rotation period shorter than 10 days show a rotation synchronized with the orbit of their hot Jupiters or have a rotation period twice the orbital period of their planets. Such rotational behaviours cannot be explained on the basis of tidal interactions alone. Besides, the gyrochronology relationship for those systems holds if an angular momentum loss rate smaller by about 30 percent than in stars without hot Jupiters is assumed.
Starspots and spin-orbit alignment in the WASP-4 exoplanetary system
Authors: Sanchis-Ojeda Roberto , Winn Joshua N. , Holman Matthew J. , Carter Joshua A. , Osip David J. , Fuentes Cesar I. 
Published: November 2011

AbstractWe present the photometric analysis of 4 transits of the exoplanet WASP-4b, obtained with the Baade 6.5m telescope, one of the two Magellan telescopes at Las Campanas. The light curves have a photometric precision of 0.5 mmag and a time sampling of 30s. This high precision has allowed us to detect several “spot anomalies”: temporary brightenings due to the occultation of a starspot on the transit chord. By analyzing these anomalies we find the sky-projected stellar obliquity to be λ = 1°+12°−14°. The small value suggests that the planet migration mechanism preserved the initially low obliquity, or that tidal evolution has realigned the system.
Stellar noise and planet detection. I. Oscillations, granulation and sun-like spots
Authors: Dumusque Xavier , Santos Nuno C. , Udry Stéphane , Lovis Cristophe , Bonfils Xavier 
Published: November 2011

AbstractSpectrographs like HARPS can now reach a sub-ms−1 precision in radial-velocity (RV) (Pepe & Lovis 2008). At this level of accuracy, we start to be confronted with stellar noise produced by 3 different physical phenomena: oscillations, granulation phenomena (granulation, meso- and super-granulation) and activity. On solar type stars, these 3 types of perturbation can induce ms−1 RV variation, but on different time scales: 3 to 15 minutes for oscillations, 15 minutes to 1.5 days for granulation phenomena and 10 to 50 days for activity. The high precision observational strategy used on HARPS, 1 measure per night of 15 minutes, on 10 consecutive days each month, is optimized, due to a long exposure time, to average out the noise coming from oscillations (Dumusque et al. 2011a) but not to reduce the noise coming from granulation and activity (Dumusque et al. 2011a and Dumusque et al. 2011b). The smallest planets found with this strategy (Mayor et al. 2009) seems to be at the limit of the actual observational strategy and not at the limit of the instrumental precision. To be able to find Earth mass planets in the habitable zone of solar-type stars (200 days for a K0 dwarf), new observational strategies, averaging out simultaneously all type of stellar noise, are required.
Gravitation Astrometric Measurement Experiment (GAME)
Authors: Gai Mario , Vecchiato Alberto , Sozzetti Alessandro , Ligori Sebastiano , Lattanzi Mario G. 
Published: November 2011

AbstractGAME (Gravitation Astrometric Measurement Experiment) is a mission concept based on astronomical techniques for high precision measurements of interest to Fundamental Physics and cosmology, in particular the γ and β parameters of the Parameterized Post-Newtonian formulation of gravitation theories extending the General Relativity.High precision astrometry also provides the light deflection induced by the quadrupole moment of Jupiter and Saturn, and, by high precision determination of the orbits of Mercury and high elongation asteroids, the PPN parameter β.The astrometric and photometric capabilities of GAME may also provide crucial complementary information on a selected set of known exo-planets.
The Italian contribution to the Gaia data processing and archiving
Authors: Martino Michele , Ciampolini Armando , Messineo Rosario , Mulone Angelo , Pigozzi Enrico , Icardi Vilma , Solitro Filomena , Castronuovo Marco M. , Lattanzi Mario G. , Morbidelli Roberto , Drimmel Ronald , Sarasso Maria , Busonero Deborah , Crosta Mariateresa , Gardiol Daniele , Vecchiato Alberto ,   the Italian Gaia Team
Published: November 2011

AbstractGaia is an ESA Cornerstone mission, scheduled to be launched in spring 2013, dedicated to precisely measure the positions and motions of over a billion stars in our galaxy: the Milky Way. Gaia Data Processing Center Turin (DPCT), the Italian DPC, is hosted and operated at ALTEC in Turin. The primary objective of DPCT is to provide the infrastructure and operations support to the Astrometric Verification Unit (AVU) activities for CU3 and the Italian participation to the Gaia data processing tasks. DPCT will archive all of the data, produced for and delivered to DPAC as part of the Italian contribution to the activities of CU4, CU5, CU7, and CU8.
Analysis of the community structure of abyssal kinetoplastids revealed similar communities at larger spatial scales
Authors: Salani Faezeh Shah , Arndt Hartmut , Hausmann Klaus , Nitsche Frank , Scheckenbach Frank 
Published: November 2011

Abstract
Knowledge of the spatial scales of diversity is necessary to evaluate the mechanisms driving biodiversity and biogeography in the vast but poorly understood deep sea. The community structure of kinetoplastids, an important group of microbial eukaryotes belonging to the Euglenozoa, from all abyssal plains of the South Atlantic and two areas of the eastern Mediterranean was studied using partial small subunit ribosomal DNA gene clone libraries. A total of 1364 clones from 10 different regions were retrieved. The analysis revealed statistically not distinguishable communities from both the South-East Atlantic (Angola and Guinea Basin) and the South-West Atlantic (Angola and Brazil Basin) at spatial scales of 1000–3000 km, whereas all other communities were significantly differentiated from one another. It seems likely that multiple processes operate at the same time to shape communities of deep-sea kinetoplastids. Nevertheless, constant and homogenous environmental conditions over large spatial scales at abyssal depths, together with high dispersal capabilities of microbial eukaryotes, maintain best the results of statistically indistinguishable communities at larger spatial scales.
Epigenetic priors for identifying active transcription factor binding sites
Authors: Cuellar-Partida Gabriel , Buske Fabian A. , McLeay Robert C. , Whitington Tom , Noble William Stafford , Bailey Timothy L. 
Published: November 2011

Abstract
Motivation Accurate knowledge of the genome-wide binding of transcription factors in a particular cell type or under a particular condition is necessary for understanding transcriptional regulation. Using epigenetic data such as histone modification and DNase I, accessibility data has been shown to improve motif-based in silico methods for predicting such binding, but this approach has not yet been fully explored.
Results We describe a probabilistic method for combining one or more tracks of epigenetic data with a standard DNA sequence motif model to improve our ability to identify active transcription factor binding sites (TFBSs). We convert each data type into a position-specific probabilistic prior and combine these priors with a traditional probabilistic motif model to compute a log-posterior odds score. Our experiments, using histone modifications H3K4me1, H3K4me3, H3K9ac and H3K27ac, as well as DNase I sensitivity, show conclusively that the log-posterior odds score consistently outperforms a simple binary filter based on the same data. We also show that our approach performs competitively with a more complex method, CENTIPEDE, and suggest that the relative simplicity of the log-posterior odds scoring method makes it an appealing and very general method for identifying functional TFBSs on the basis of DNA and epigenetic evidence.
Availability and implementation: FIMO, part of the MEME Suite software toolkit, now supports log-posterior odds scoring using position-specific priors for motif search. A web server and source code are available at http://meme.nbcr.net. Utilities for creating priors are at http://research.imb.uq.edu.au/t.bailey/SD/Cuellar2011.
Contact: t.bailey@uq.edu.au
Supplementary information: Supplementary data are available at Bioinformatics online.