bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic fields in dwarfs versus early-type galaxies
Authors: Chyży Krzysztof T. 
Published: October 2010

AbstractAccording to a recent systematic study of dwarf irregular galaxies the production of their magnetic fields appears to be regulated mainly by the surface density of the galactic star-formation rate. Magnetic fields in nearby dwarfs are typically weak, with the mean value of the total field strength three times smaller than in the normal spirals. Dwarfs with stronger fields reveal vivid star-forming activity, have clear signs of current or recent gravitational interactions, are more massive and evolved systems. Recently discovered strong regular fields in an early-type ringed galaxy NGC 4736 also indicates that even without spiral density waves an effective generation of strong magnetic fields is possible in any type of galaxy if only starburst characteristics are reached.
Magnetic turbulence in clusters of galaxies
Authors: Enßlin T. A. , Clarke T. , Vogt C. , Waelkens A. , Schekochihin A. A. 
Published: October 2010

AbstractGalaxy clusters are large laboratories for magnetic plasma turbulence and therefore permit us to confront our theoretical concepts of magnetogenesis with detailed observations. Magnetic turbulence in clusters can be studied via the radio-synchrotron emission from the intra-cluster medium in the form of cluster radio relics and halos. The power spectrum of turbulent magnetic fields can be examined via Faraday rotation analysis of extended radio sources. In case of the Hydra A cool core, the observed magnetic spectrum can be understood in terms of a turbulence-mediated feedback loop between gas cooling and the jet activity of the central galaxy. Finally, methods to measure higher-order statistics of the magnetic field using Stokes-parameter correlations are discussed, which permit us to determine the power spectrum of the magnetic tension force. This fourth-order statistical quantity offers a way to discriminate between different magnetic turbulence scenarios and different field structures using radio polarimetric observations.
NEI Modelling of the ISM - Turbulent Dissipation and Hausdorff Dimension
Authors: de Avillez Miguel A. , Breitschwerdt Dieter 
Published: October 2010

AbstractHigh-resolution non-ideal magnetohydrodynamical simulations of the turbulent magnetized ISM, powered by supernovae types Ia and II at Galactic rate, including self-gravity and non-equilibriuim ionization (NEI), taking into account the time evolution of the ionization structure of H, He, C, N, O, Ne, Mg, Si, S and Fe, were carried out. These runs cover a wide range (from kpc to sub-parsec) of scales, providing resolution independent information on the injection scale, extended self-similarity and the fractal dmension of the most dissipative structures.
A Summary of 3-D Reconstructions of the Whole Heliosphere Interval and Comparison with in-Ecliptic Solar Wind Measurements from STEREO, ACE, and Wind Instrumentation
Authors: Bisi Mario M. , Jackson B. V. , Clover J. M. , Hick P. P. , Buffington A. , Tokumaru M. 
Published: October 2010

AbstractWe present a summary of results from simultaneous Solar-Terrestrial Environment Laboratory (STELab) Interplanetary Scintillation (IPS), STEREO, ACE, and Wind observations using three-dimensional reconstructions of the Whole Heliosphere Interval – Carrington rotation 2068. This is part of the world-wide IPS community's International Heliosphysical Year (IHY) collaboration. We show the global structure of the inner heliosphere and how our 3-D reconstructions compare with in-ecliptic spacecraft measurements.
On Cosmic Rays, IP Structures and Geospace Consequences During WHI
Authors: Lago A. Dal , Guarnieri F. L. , da Silva M. R. , Gonzalez W. D. , Braga C. R. , Schuch N. J. , Munakata K. , Kato C. , Bieber J. W. , Kuwabara T. , Tokumaru M. , Duldig M. L. , Humble J. E. 
Published: October 2010

AbstractThis work presents some observations during the period of the Whole Heliosphere Interval (WHI) of the effects of interplanetary (IP) structures on the near-Earth space using three sets of observations: magnetic field and plasma from the Advanced Composition Explorer (ACE) satellite, ground-based cosmic ray data from the Global Muon Detection Network (GMDN) and geomagnetic indices (Disturbance storm-time, Dst, and auroral electrojet index, AE). Since WHI was near minimum solar activity, high speed streams and corotating interaction regions (CIRs) were the dominant structures observed in the interplanetary space surrounding Earth. Very pronounced geomagnetic effects are shown to be correlated to CIRs, especially because they can cause the so-called High-Intensity Long-Duration Continuous AE Activity (HILDCAAs) - Tsurutani and Gonzalez (1987). At least a few high speed streams can be identified during the period of WHI. The focus here is to characterize these IP structures and their geospace consequences.
WHI High-Speed Streams at Geospace
Authors: Maris G. , Maris O. 
Published: October 2010

AbstractThe fast solar wind analysis during the Whole Heliospheric Interval (Carrington Rotation no. 2068: March 20 - April 16, 2008) is herein presented. The analysis is based on the data recorded by space experiments aboard the ACE and SOHO missions. The high-speed streams in the solar wind were determined by their main parameters: duration, maximum velocity, velocity gradient. The fast solar wind was also analyzed during the preceding and following Carrington Rotations, nos. 2067 and 2069, respectively. The main properties of the rapid streams and their solar sources were analysed in terms of the present solar minimum phase. The geospace response to the fast streams was evaluated using the geomagnetic index dynamics. A comparative analysis of the high-speed streams registered during Whole Heliospheric Interval with the ones determined during Whole Sun Month was also made.
The Future of IHY Campaigns: Transition to the International Space Weather Initiative
Authors: Raulin Jean-Pierre , Davila Joseph M. , Bogdan Thomas , Yumoto Kiyohumi , Leibacher John 
Published: October 2010

AbstractWe will present the relevant activities performed during the International Heliophysical Year (IHY) program during the 5 year period 2004 - 2008. The IHY was a major international effort that involved the deployment of new instrumentation, new observations from the ground and in space, and a strong education component. Under the United Nations Office for Outer Space program called Basic Space Science Initiative (UNBSSI), instrument arrays have been deployed to provide global measurements of heliophysical phenomena. As a result, significant scientific and educational collaborations emerged between the organizing groups and the host country teams. In view of the great successes achieved by the IHY during these years, we propose to continue the highly successful collaboration with the UN program to study the universal processes in the solar system that affect the interplanetary and terrestrial environments, and to continue to coordinate the deployment and operation of new and existing instrumentation arrays aimed at understanding the impacts of Space Weather on Earth and the near-Earth environment. To this end, we propose a new program, the International Space Weather Initiative (ISWI). The ISWI strongly complements the International Living With a Star (ILWS) program, providing more attention nationally, regionally, and internationally for the ILWS program. Based on a three-year program activity, the ISWI would provide the opportunity for scientists around the world to participate in this exciting quest to understand the effect of space disturbances on our Earth environment.
Astronomy in Antarctica in 2009
Authors: Burton Michael G. 
Published: October 2010

AbstractThis article summarises the subject matter of Special Session 3 at IAU General Assembly XXVII in Rio de Janeiro, Brazil, which took place on August 6-7, 2009. In it, we overview the state of Astronomy in Antarctica as it is in 2009. Significant astronomical activity is now taking place at four stations on the Antarctic plateau (South Pole, Domes A, C & F), as well as at the coastal station of McMurdo.
Astronomy and Astrophysics from Antarctica: a new SCAR Scientific Research Program
Authors: Storey J. W. V. 
Published: October 2010

AbstractIn July 2008 the IAU became a union member of the ICSU body SCAR—the Scientific Committee on Antarctic Research. At the same time, SCAR initiated a Planning Group to establish a Scientific Research Program in Astronomy and Astrophysics from Antarctica. Broadly stated, the objectives of Astronomy and Astrophysics from Antarctica are to coordinate astronomical activities in Antarctica in a way that ensures the best possible outcomes from international investment in Antarctic astronomy, and maximizes the opportunities for productive interaction with other disciplines.
The LUCAS program: detecting vegetation and traces of life in the Earthshine
Authors: Briot Danielle , Arnold Luc , Jacquemoud Stéphane , Schneider Jean , Agabi Karim , Aristidi Eric , Berthier Jérôme , Bondoux Erick , Challita Zalpha , Petermann Denis , Pouzenc Cyprien , Rocher Patrick 
Published: October 2010

AbstractThe aim of the LUCAS program is to observe chlorophyll and atmospheric molecules in the Earthshine spectrum in order to prepare the detection of life in terrestrial extrasolar planets to be discovered. Actually, observations from Antarctica offer a unique possibility to study the variations of Earthshine spectrum during Earth rotation while various parts of Earth are facing the Moon. Special instrumentation for the LUCAS program was designed and put in the Concordia station in the Dome C. Observations are in progress.
Site testing on the Greenland Ice Cap
Authors: Andersen M. I. , Pedersen K. , Sørensen A. N. 
Published: October 2010

AbstractWe present a site testing program initiated at the SUMMIT station on the Greenland Ice Cap. A DIMM was mounted in the SWISS tower, 39 m above the ice level, during a period of 3 weeks in the late Arctic summer 2008. Tracking Polaris, the DIMM obtained continuous seeing measurements. The campaign was hampered by poor weather and the measured seeing was fluctuating, suggesting that the boundary layer was very unstable. However, during short periods, the un-calibrated seeing went below 0″.5, indicating that the free atmosphere seeing above Greenland is not significantly different from what is found above the Antarctic plateau.
CSTAR and future plans for Dome A
Authors: Cui Xiangqun 
Published: October 2010

AbstractThe first set of Chinese Antarctic telescopes at Dome A is called CSTAR. It consists of four 14.5 cm wide-field telescopes and was installed at Dome A during the traverse of 2007/2008. CSTAR successfully operated for 135 days in 2008 and for more than 200 days in 2009. This paper briefly introduces recent developments in Chinese Antarctic astronomy and their international collaborative activities. It also describes future plans for Dome A, as the building of Kunlun Station began in January of this year.
The great oxidation of Earth's atmosphere
Authors: Musielak Zdzislaw E. , Cuntz Manfred , Roy Dipanjan 
Published: October 2010

AbstractA simplified model of the Earth's atmosphere consisting of three nonlinear differential equations with a driving force was developed by Goldblatt et al. (2006). They found a steady-state solution that exhibits bistability and identified its upper value with the great oxidation of the Earth's atmosphere. Noting that the driving force in their study was a step function, it is the main goal of this paper to investigate the stability of the model by considering two different more realistic driving forces. The stability analysis is performed by using Lyapunov exponents. Our results show that the model remains stable and it does not exhibit any chaotic behavior.
Selection of most promising CoRoT candidates for radial-velocity follow-up
Authors: Da Silva Ronaldo , Silva-Valio Adriana 
Published: October 2010

AbstractWe used the method of Silva & Cruz (2006), which distinguishes between planetary and stellar companions by fitting transit light curves, to select the most promising CoRoT candidates to be monitored with radial-velocity measurements. Testing this method on the light curves of confirmed CoRoT exoplanetary systems shows that the estimated radius for such planets is smaller than 2 RJup, while for most of the light curves in which no planet has been detected, the secondary companion has an estimated radius larger than 2 RJup. We present preliminary results concerning other light curves for which no planet has been detected yet.
Modelling extrasolar planetary atmospheres
Authors: Allard France 
Published: October 2010

AbstractThe atmospheres of close-in Extrasolar Giant Planets (EGPs) experience important stellar radiation, raising the question of the heat redistribution around the planetary surface and of the importance of photochemistry effects for their spectral properties. They experience mass loss via quasi-thermal escape of their lightest elements. They rotate and experience tidal effects. Model atmospheres struggle to include even part of this complexity. Some address the dynamics of the atmospheres as a whole (3D) as subjected to rotation, or as patches of the surface (wind studies), compromising on the details of the composition and radiative/convective properties. Others solve the composition and radiative/convective properties, compromising on dynamical effects such as rotation. In this paper, we review existing model atmospheres for EGPs, and present the first high spatial resolution local (as opposed to global) 2/3D radiation hydrodynamic simulations of EGP atmospheres including dust cloud formation.
The discovery of glycolaldehyde in a star forming region
Authors: Beltràn Maria T. , Codella Claudio , Viti Serena , Neri Roberto , Cesaroni Riccardo 
Published: October 2010

AbstractGlycolaldehyde is the simplest of the monosaccharide sugars and is directly linked to the origins of life. We report on the detection of glycolaldehyde (CH2OHCHO) towards the hot molecular core G31.41+0.31 through observations with the IRAM PdBI (Plateau de Bure Interferomter) at 1.4, 2.1, and 2.9 mm.
The SEE-COAST concept
Authors: Boccaletti Anthony , Sozzetti Alessandro , Schneider Jean , Baudoz Pierre , Tinetti Giovanna , Stam Daphne 
Published: October 2010

AbstractThe SEE COAST concept is designed with the objective to characterize extrasolar planets and possibly Super Earths via spectro-polarimetric imaging in reflected light. A space mission complementary to ground-based near IR planet finders is a first secure step towards the characterization of planets with mass and atmosphere comparable to that of the Earth. The accessibility to the Visible spectrum is unique and with important scientific returns.
Accretion Disks in the Sub-Stellar Realm: Properties and Evolution
Authors: Jayawardhana Ray 
Published: October 2010

AbstractIt is now well established that young brown dwarfs harbor accretion disks –and thus undergo a T Tauri phase– similar to their low-mass stellar counterparts. The supporting evidence includes infrared and millimeter observations of the dust component as well as optical and infrared spectra with signatures of gas accretion and outflow. Recent findings suggest that disks are common even around young planetary mass objects. The ubiquity of circum-sub-stellar disks not only hints at a common formation scenario for PMOs, brown dwarfs and stars, but also offers a new regime for investigating processes such as episodic accretion, grain growth and disk clearing.
Circumstellar disks in high-mass star environments: the early solar system
Authors: Montmerle Thierry , Gounelle Matthieu , Meynet Georges 
Published: October 2010

AbstractThe early solar system represents the only case we have of a circumstellar disk that can be investigated “in situ” -albeit 4.6 Gyr after its formation. Meteorites studies give mounting evidence for an intense irradiation phase of the young circumsolar disk by energetic particles, and also for contamination by products of high-mass stellar and/or explosive nucleosynthesis. We thus discuss the conditions of the birth of the solar system in a high-mass star environment.
Warm and hot circumstellar gas in V1647 Ori during the 2008-2009 outburst
Authors: Carmona A. , Audard M. , van den Ancker M. , van der Plas G. , Goto M. , Fedele D. 
Published: October 2010

AbstractThe pre-main sequence star V1647 Ori started a new outburst in August 2008. From October 2008 to February 2009 we monitored V1647 Ori, obtaining quasi-simultaneous VLT-CRIRES near-IR spectroscopy, VLT-VISIR mid-IR spectroscopy and VLT-FORS2 optical spectroscopy. We studied the evolution of H2 and CO emission from hot and warm gas and Hα and forbidden line-emission during the initial outburst phase of V1647 Ori. Hα is observed in emission displaying P-Cygni profiles with blue-shifted absorption up to –700 km/s, suggesting the presence of a high velocity wind (Fig. 1a). [OI] emission at 6300 Å is observed displaying a blue-shifted emission shoulder, indicating the presence of material moving away from the star (Fig. 1b). We detect H2 1-0 S(1) and CO (P4 to P14 and P30-P38) ro-vibrational lines centered at the velocity of the star at all epochs (Fig. 1c & d). This strongly suggests that the H2 and CO emission originates from a disk and not from a warm outflow. The H2 1–0 S(0) and 2-1 S(1) ro-vibrational lines at 2.22 and 2.24 μm and the pure-rotational H2 0–0 S(1) and 0–0 S(2) lines at 17 and 12 μm were not detected in our spectra. Changes in the Hα and [OI] profiles and the H2 and CO emission observed do not correlate. We modeled the H2 and CO line profiles assuming emission from a flat disk in keplerian rotation with line intensity decreasing with radius (I ~ I0(R/Rmin)−α). We found that the disk of V1647 Ori is observed nearly face-on and that the line emission is produced within a fraction of an AU of the star (Fig. 1d).
Prospects for planet formation in multiple stellar systems
Authors: Duchêne Gaspard 
Published: October 2010

AbstractAs I review here, planet formation in multiple stellar systems is far from exceptional. However, it appears that binaries with projected separation in the 5–100 AU range have different initial conditions and end result properties than wider systems, probably because they undergo different physical processes. In addition, very tight binaries, with projected separation less than a few AU, seem to fulfill all the known requirements to form planetary systems, suggesting that circumbinary planets are very likely to exist.
The Role of Multiplicity in Protoplanetary Disk Evolution
Authors: Kraus Adam L. , Ireland Michael J. 
Published: October 2010

AbstractInteractions with close stellar or planetary companions can significantly influence the evolution and lifetime of protoplanetary disks. It has recently become possible to search for these companions, directly studying the role of multiplicity in protoplanetary disk evolution. We have described an ongoing survey to directly detect these stellar and planetary companions in nearby star-forming regions. Our program uses adaptive optics and sparse aperture mask interferometry to achieve typical contrast limits of Δ K=5-6 at the diffraction limit (5–8 MJup at 5–30 AU), while also detecting similar-flux binary companions at separations as low as 15 mas (2.5 AU). In most cases, our survey has found no evidence of companions (planetary or binary) among the well-known “transitional disk” systems; if the inner clearings are due to planet formation, as has been previously suggested, then this paucity places an upper limit on the mass of any resulting planet. Our survey also has uncovered many new binary systems, with the majority falling among the diskless (WTTS) population. This disparity suggests that disk evolution for close (5–30 AU) binary systems is very different from that for single stars. As we show in Figure 1, most circumbinary disks are cleared by ages of 1–2 Myr, while most circumstellar disks are not. These diskless binary systems have biased the disk frequency downward in previous studies. If we remove our new systems from those samples, we find that the disk fraction for single stars could be higher than was previously suggested.
Stellar and brown dwarf properties from numerical simulations
Authors: Bate Matthew R. 
Published: October 2010

AbstractWe review the statistical properties of stars and brown dwarfs obtained from the first hydrodynamical simulation of star cluster formation to produce more than a thousand stars and brown dwarfs while simultaneously resolving the lowest mass brown dwarfs (those with masses set by the opacity limit for fragmentation), binaries with separations down to ~ 1 AU, and discs with radii greater than ~ 10 AU. In particular, we present the eccentricity distribution of the calculation's very-low-mass and brown dwarf binaries which has not been previously published.
New and old roles for narrowband Hα
Authors: Drew Janet E. 
Published: October 2010

AbstractUntil recently, Hα has been seen as the tracer of ionized gas, picking out both star formation and the late stages of stellar evolution. This has been reaffirmed, spectacularly, by the recent WHAM and SHS surveys. But the advent of large-area digital detectors creates a new role for narrowband Hα as a direct, simultaneous, measure of intrinsic stellar colour and reddening when e.g. r'-Hα is combined with a nearby broad band colour e.g. r'- i'. This new capability has been clearly demonstrated by the nearly-complete IPHAS survey.
Billions of stars: the near infrared view of the Plane with UKIDSS and VISTA
Authors: Lucas Philip W. , Samuel David 
Published: October 2010

AbstractThe UKIDSS Galactic Plane Survey (GPS) is surveying the northern and equatorial plane in the J, H and K bands. Here we report initial results from searches for new clusters and star formation regions. 248 clusters have been detected by our Bayesian search, of which 127 are new. A visual inspection of the images is also proving successful. A cross match with Spitzer-GLIMPSE to find clusters of Young Stellar Objects is being attempted. No new globular clusters are detected except for two likely candidates already detected by Mercer et al. in GLIMPSE.
ATLASGAL, the APEX Telescope Large Area Survey of the Galaxy
Authors: Schuller F. , Menten K. M. , Wyrowski F. , Beuther H. , Bontemps S. , Bronfman L. , Contreras Y. , Henning T. , Motte F. , Schilke P. , Walmsley M. , Zavagno A. 
Published: October 2010

AbstractSubmillimeter continuum emission traces high molecular column densities and, thus, dense cloud regions in which new stars are forming. Surveys of the Galactic plane in such emission have the potential of delivering an unbiased view of high-mass star formation throughout the Milky Way. Here we present the scope, current status and first results of ATLASGAL, an ongoing survey of the Galactic plane using the Large APEX Bolometer Camera (LABOCA) on the Atacama Pathfinder Experiment (APEX) telescope at the Chajnantor plateau in Chile. Aimed at mapping 360 square degrees at 870 μm, with a uniform sensitivity of 50 mJy/beam, this survey will provide the first unbiased sample of cold dusty clumps in the Galaxy at submillimeter wavelengths. These will be targets for molecular line follow-up observations and high resolution studies with ALMA and the EVLA.
Exploring Extinction and Structure in the Milky Way Disk With 2MASS and Spitzer
Authors: Zasowski G. , Majewski S. R. , Nidever D. L. , Indebetouw R. 
Published: October 2010

AbstractWe present new maps of the distribution of both dust and stars across the Galactic disk, based largely on an improved analysis of 2MASS and Spitzer-IRAC data. The infrared extinction law is rederived throughout the disk and we found strong longitudinal variations in both diffuse and dense environments that we incorporate in our analysis.