bluuebunny/crossref_metadata_2025_split huggingface dataset:
Martian Surface Composition as Determined by the MGS Thermal Emission Spectrometer
Authors: Ruff Steve R. , Christensen Philip R. , Bandfield Joshua L. , Hamilton Victoria E. , Kieffer Hugh H. , Morris Richard V. , Lane Melissa D. , Malin Michael C. 
Published: March 2016

AbstractThe surface composition of Mars has been investigated using the Thermal Emission Spectrometer (TES) instrument during the mapping phase of the Mars Global Surveyor mission. The TES has mapped ~85% of the Martian surface at a resolution of 3-9 km. Separation of the atmospheric dust, water-ice cloud, CO2, water vapor, and surface components has been accomplished using radiative transfer and deconvolution. Two distinct surface compositional units have been mapped; (1) a basalt with plagioclase feldspar, Ca-rich pyroxene, minor sheet silicates; and (2) a basaltic andesite with silica glass, plagioclase, and minor pyroxene. Three large-scale (100’s km) accumulations of hematite have been found in Sinus Meridiani, Aram Chaos and Ophir/Candor Chasms. These regions are interpreted to be formed by aqueous precipitation under either ambient or hydrothermal conditions. No surfaces with detectable abundances of carbonate have been found. The albedo of the surface has been mapped with an absolute accuracy of ~1-2% and significant changes in surface albedo have occurred from the orbital measurements obtained by the Viking IRTM instrument.
Missions to Phobos and Other Minor Bodies
Authors: Avduevsky Vsevolod S. , Akim Efraim L. , Eneev Timur M. , Marov Mikhail Ya. , Kulikov Stanislav D. , Kremnev Roald S. , Popov Garry A. 
Published: March 2016

AbstractA space mission to Mars’ moon Phobos with a space vehicle of new generation currently developed by the Russian Aerospace Agency is discussed. The vehicle design incorporates innovative SEP technology focused on small propulsion electric engines which significantly improve the mission energetic capability. The project is optimized around a sample return (PSR) from Phobos and also offers an opportunity for rendezvous/sample return missions from several asteroids, comets, and NEO. Scenario, rationale, and basic profile of PSR mission are presented.
Modelling of the Coherent Backscattering Opposition Effect: Comparison to Planetary Phase Curves
Authors: Kaasalainen Sanna , Muinonen Karri , Piironen Jukka 
Published: March 2016

AbstractWe study the opposition effect of icy planetary satellites by means of a Monte Carlo simulation of the coherent backscattering opposition effect for spherical objects covered with locally plane parallel media.
A Classical Cycle of Activity in the North Tropical Region of Jupiter, 1996-1999
Authors: Rogers John , Foulkes Michael , Mettig Hans-Joerg 
Published: March 2016

AbstractJupiter’s North Equatorial Belt (NEB) occasionally undergoes cycles of activity that consist of rapid broadening of the dark belt to the north, often accompanied by cyclonic bright “rift” activity, followed by development of large circulations in the expanded northern part (cyclonic dark “barges” and anticyclonic bright “portholes”), and a reddish colour across the belt (Rogers 1995). In 1996 there was a classic NEB broadening event with typical evolution over the following years. The broadening to the north began in 1996 April and spread around the belt by the summer. By 1997 April, there was an array of “barges” and “portholes” (white ovals) all around the broadened NEB, and increased redness of the belt. During 1997 the northern extension gradually reverted towards the normal bright albedo for this latitude, but the barges and ovals persisted. Indeed they still persist in 1999/00. Features in 1998/99/00 have included a rapidly-prograding white oval which destroyed barges ahead of it and had retrograding dark spots created following it; these retrograding spots have circulated as was observed in Voyager maps.
OB Associations, Open Clusters, and the Luminosity Calibration of the Nearer Stars
Authors: Brown Anthony 
Published: March 2016

AbstractIn the context of the luminosity calibration of the nearer stars I discuss the Hipparcos results on distances to nearby OB associations and open clusters. The shortcomings and assumptions in the analyses used to derive these results are pointed out and for the open clusters a comparison is made with results obtained from main sequence fitting. I conclude that given the considerable uncertainties in the latter technique there is no convincing evidence that the Hipparcos based distances to open clusters beyond the Hyades should not be trusted.
Luminosity Calibrations with Hipparcos: Theoretical Point of View
Authors: Lebreton Yveline 
Published: March 2016

AbstractHipparcos provided us with valuable observational material that can be used to anchor more firmly the Galactic and extragalactic distance scales. A calibration which is applicable to all stars must allow for differences in chemical composition and other properties, which may require the use of theoretical models. I discuss some difficulties encountered in the calibration procedure that are related (1) to the determinations of stellar temperatures, luminosities and chemical compositions, (2) to remaining weaknesses of theoretical stellar models, and (3) to the transformations of the model outputs from the (Mbol, Teff) plane into any colour-magnitude or colour-colour diagram.
HIPPARCOS and the Calibration of the MK System
Authors: Garrison R.F. 
Published: March 2016

AbstractThe HIPPARCOS satellite has provided astronomy with a wonderful legacy. We now have high-quality parallaxes for some of the yellow and red giants as well as for some of the A and F main sequence standards. It is now possible to compare field giants with those in globular clusters and to resolve some of the discrepancies. Hipparcos luminosities are being compared with various existing MK calibrations and the most glaring (i.e. interesting) inconsistencies will be discussed.
Red Clump Stars – Further Improved Distance Indicator
Authors: Garnavich P.M. , Stanek K. 
Published: March 2016

AbstractThe ideal distance indicator would be a standard candle abundant enough to provide many examples within reach of parallax measurements and sufficiently bright to be seen out to Local Group galaxies. The red clump stars closely match this description. These are the metal rich equivalent of the better known horizontal branch stars, and their brightness dispersion is only 0.2 mag (one sigma) in the Solar neighborhood. Using Hipparcos to calibrate a large, local sample, the red clump method has been used to measure accurate distances to the Galactic center (Paczyński & Stanek 1998), M31 (Stanek & Garnavich 1998), LMC (Udalski et al. 1998; Stanek et al. 1998; Udalski 1999) and some clusters in our Galaxy (e.g. 47Tuc: Kaluzny et al. 1998). As with all the distance indicators, the main worry lies in the possible systematics of the method, in particular, the brightness dependence on the stellar metallicity and age. These dependences have come under close scrutiny and, indeed, the population effects on the red clump brightness appear small and calibratable. Perhaps the most controversial result from the red clump method is the estimation of a “short” distance to the Large Magellanic Cloud (Udalski et al. 1998; Stanek, Zaritsky & Harris 1998; Udalski 2000). This distance to the LMC is shorter by 12% than the “standard” value, and has very important implications for the Cepheid distance scale and the determination of the Hubble constant.
Magnetic Fields in Young Galaxies
Authors: Nordlund Åke , Rögnvaldsson Örnólfur 
Published: March 2016

AbstractWe have studied the fate of initial magnetic fields in the hot halo gas out of which the visible parts of galaxies form, using three-dimensional numerical MHD-experiments. The halo gas undergoes compression by several orders of magnitude in the subsonic cooling flow that forms the cold disk. The magnetic field is carried along and is amplified considerably in the process, reaching μG levels for reasonable values of the initial ratio of magnetic to thermal energy density.
Recent Results on Magnetic Fields in the Milky Way
Authors: Wielebinski R. , Reich W. , Fürst E. 
Published: March 2016

AbstractOf all the methods available to observe magnetic fields in the Milky Way, the mapping of linear polarization at cm wavelengths has proven to be most successful. The instruments that have contributed most of the new data are the 100 m Effelsberg telescope and the Parkes 64 m dish. Their Galactic plane surveys gave us a new conception of the linear polarization distribution. A new Effelsberg 1.4 GHz ‘medium latitude polarization survey’ now being made gives us data about large sections of the Galaxy. Polarization maps of selected regions of the Galaxy are now being made at several frequencies up to 32 GHz. Data from Westerbork at ∼ 325 MHz, as well as data from the Canadian Galactic Plane Survey (CGPS) at 1.4 GHz give new exciting information.
Dark Matter: Astronomical Aspects
Authors: Trimble Virginia 
Published: March 2016

AbstractThe chief evidence for appreciable dark matter in the universe comes from the monotonic increase in mass to light ratios measured for various astronomical systems as one looks on larger and larger length scales. Though the evidence comes from photons, most of the dark matter is non-photonic, and, for that matter, non-baryonic. There remain several questions about the nature and behavior of dark matter to which conventional astronomical observations are (probably) relevant. The most germain to this JD is whether astronomers have seen decay or annihilation products from dark matter particles, to which the current answer seems to be no. We look at a few of the others.
Recent Advances in Ground-Based Observation of Mercury
Authors: Warell J. 
Published: March 2016

AbstractThe last decade has seen an efficient use of ground-based telescopes for remote-sensing studies of Mercury’s surface at optical, infrared and microwave wavelengths. This has resulted in a substantially improved knowledge of its regolith composition, material and light scattering properties and structures on the poorly known hemisphere. This paper summarizes recent observations and results on the regolith properties of Mercury.
The BepiColombo Mission
Authors: Schulz Rita , Falkner Peter , Peacock Anthony , Erd Christian , Rando Nicola , Kraft Stefan 
Published: March 2016

AbstractBepiColombo is an interdisciplinary mission to the planet Mercury which will provide the detailed information necessary to understand Mercury and its magnetospheric environment. The mission is envisaged to consist of three spacecrafts, the Mercury Planetary Orbiter (MPO), the Mercury Magnetospheric Orbiter (MMO) and the Mercury Surface Element (MSE). The mission went through a re-assessment with the aim of optimizing resources and and advancing the scientific return. Various mission scenarios were investigated and new pay load concepts were adopted. The newly defined mission will be presented focusing on the launch scenario and the MPO reference payload.
Summaries of Papers Presented at Joint Discussion Session 4: Astrophysical Impact of Abundances in Globular Cluster Stars
Authors: Da Costa G. S. , D’Antona F. , Gratton R. G. 
Published: March 2016

AbstractIn this contribution we give summaries of the oral and poster papers presented in Joint Discussion Session 4, Astrophysical Impact of Abundances in Globular Cluster Stars, at the XXVth IAU General Assembly. The full text of the papers can be found in Volume 75, issue 2, of the MEMORIE della Società Astronomica Italiana (Journal of the Italian Astronomical Society; see the web address: <sait.oat.ts.astro.it>).
From Young to Old: Spectral Models for Star Cluster Systems
Authors: Alvensleben Uta Fritze – v. , Anders Peter , de Grijs Richard 
Published: March 2016

AbstractEvolutionary synthesis models for star clusters of various metallicities, including gaseous emission during the lifetime of the ionizing stars, are used to model star cluster systems comprising two populations: an old metal-poor globular cluster (GC) population similar to that of the Milky Way halo, and a second GC population of arbitrary metallicity. We investigate the time evolution of color distributions and luminosity functions for the two GC populations and compare with observations of E/SO galaxies. We show that multi-passband data for GC populations give clues to the relative ages and metallicities of the two subpopulations, and help constrain formation scenarios for their parent galaxies.
Formation of Globular Clusters in Galaxy Mergers
Authors: Bekki Kenji , Couch Warrick J. , Forbes Duncan A. , Beasley M. A. 
Published: March 2016

AbstractOur numerical simulations first demonstrate that the pressure of ISM in a major merger becomes so high (> 105 kB K cm-3) that GMCs in the merger can collapse to form globular clusters (GCs) within a few Myr. The star formation efficiency within a GMC in galaxy mergers can rise up from a few percent to ~ 80 percent, depending on the shapes and the temperature of the GMC. This implosive GC formation due to external high pressure of warm/hot ISM can be more efficient in the tidal tails or the central regions of mergers. The developed clusters have King-like profiles with an effective radius of a few pc. The structural, kinematical, and chemical properties of these GC systems can depend on the orbital and chemical properties of major mergers.
Dynamical Evolution of Globular Cluster Systems
Authors: Vesperini E. 
Published: March 2016

AbstractI present the results of a number of simulations of the dynamical evolution of globular cluster systems (GCS) in elliptical galaxies including the effects of two-body relaxation, dynamical friction, stellar evolution and the effects of the tidal field of the host galaxy. The results of detailed models for the evolution of the M87 GCS are also presented. A significant number of clusters are disrupted by evolutionary processes and the properties of many of the clusters which survive are effected by dynamical evolution. In spite of large differences in the efficiency of evolutionary processes in different galaxies, the final galaxy-to-galaxy variation of the GCS mean mass and its radial variation within individual galaxies in my simulations are small and consistent with observations. The effects of dissolution of low-concentration clusters due to mass loss through stellar evolution are also discussed and are shown to play an important role in the evolution of a power-law GCS mass function (GCMF), similar to that observed in young cluster systems in merging galaxies, towards a final GCMF with properties consistent with observations.
Multi-Color Observations of Young Star Clusters
Authors: Anders Peter , Alvensleben Uta Fritze – v. , de Grijs Richard 
Published: March 2016

AbstractWe present a new set of evolutionary synthesis models of our GALEV code, specifically developed to include the gaseous emission of presently forming star clusters, in combination with an advanced tool to compare large model grids with multi-color broad-band observations of YSC systems. Tests and first applications are presented.
2dF Spectroscopy of Globular Clusters in M104
Authors: Bridges Terry , Zepf Steve , Rhode Katherine , Freeman Ken 
Published: March 2016

AbstractWe have found 56 new globular clusters in M104 from 2dF multi-fiber spectroscopy, doubling the number of confirmed clusters, and extending the spatial coverage to 50 kpc radius. We find no significant rotation in the total sample, or for subsets split by color or radius. However, there are hints that the blue clusters have a higher rotation than the red clusters, and for counter-rotation of clusters at large radius. We find a total mass of M ~ 1 × 1012M⊙ and a (M/L)B =30 out to 50 kpc radius, which is strong evidence for a dark matter halo in M104.
Globular Cluster Formation in Galaxy Mergers
Authors: Li Yuexing , Mac Low Mordecai-Mark , Klessen Ralf S. 
Published: March 2016

AbstractWe present preliminary results of a high resolution simulation of globular cluster formation in a galaxy merger using GADGET (Springel et al. 2001). A barotropic equation of state (Li et al 2003) is implemented to include effects of cooling and heating. After one orbital period, a dozen proto-globular clusters are identified in the tidal tails.
Joint Discussion 9: Astrotomography
Authors: Cameron Andrew Collier , Schwope Axel , Vrielmann Sonja 
Published: March 2016

AbstractEven in the new millenium, many astronomical objects cannot be resolved spatially with any available telescope. Most stars are too small and galaxies are too far away to be imaged directly or in detail in the foreseeable future. However, advances in data-analysis techniques allow us now to create detailed indirect images using tomographic methods. These images provide unprecedented insights into fundamental processes that drive the evolution of stars and galaxies, such as accretion and magnetic-field generation, on length scales that are of great physical importance but which are otherwise inaccessible.Joint Discussion 09 was held on two half-days during the General Assembly. The main proceedings will be published in full in a special issue of Astronomische Nachrichten, to which the reader is referred, early in 2004. Here we give only a brief listing of subjects addressed and the titles of talks presented at the meeting.
Clusters in the Optical
Authors: Lubin Lori M. 
Published: March 2016

AbstractI present a brief review of studies of galaxy clusters in the optical. Clusters of galaxies were historically detected in the optical, and this selection provided the first large, statistical samples of clusters. I describe how these samples have been instrumental in characterizing the properties of the local cluster population, tracing large scale structure, and constraining cosmology. More sophisticated cluster detection techniques in the optical have now made it possible to detect large numbers of clusters up to z ~ 1.4. I describe these advances and discuss how large-area and deep surveys are being used to determine the evolution in the global cluster properties and the properties of cluster galaxy populations.
Radio Halo and Relic Sources in Galaxy Clusters
Authors: Wu Kinwah , Johnston-Hollitt Melanie , Hunstead Richard 
Published: March 2016

AbstractWe review briefly the general properties of halo and relic sources in galaxy clusters. We also present a polarized radiative transfer algorithm which is useful for calculations of polarized radio emission from halos, relics and active galaxies in a magnetized intra-cluster medium.
A New Scenario for the Formation of Massive Stellar Clusters
Authors: Palouš Jan , Tenorio-Tagle Guillermo , Silich Sergiy , Medina-Tanco Gustavo A. , Muñoz-Tuñon Casiana 
Published: March 2016

AbstractA new scenario is proposed, in which the continuous creation of stars results into a highly concentrated massive (globular cluster-like) stellar system. We assume that the collapse of a massive cloud leads to the formation of first stars. Their winds and terminal supernova explosions create a standing, small radius, cold and dense shell, where the next stars form. The shell is in steady state location, which is due to a detailed balance established between the ram pressure from the collapsing cloud, the gravitational force exerted on the shell and the ram pressure of the stellar wind from the forming cluster. In this contribution we show that the standing shell remains stable against Rayleigh -Taylor instability, and discuss future prospects of this work.
Asteroseismology: From Dream to Reality
Authors: Kurtz D. W. 
Published: March 2016

AbstractWith the resounding success of Helioseismology in determining the interior structure and rotation of the Sun, and in providing unprecedented studies of the interaction of pulsation and magnetic fields in the solar atmosphere, astronomers have been delighted, after decades of disappointing attempts, with the recent discovery of solar-like oscillations in ξHya, β Hyi, αCen, η Boo and νInd. There is now true seismology of a variety of solar-like stars. Asteroseismology also studies stars with a wide variety of interior and surface conditions. For two decades asteroseismic techniques have been applied to many pulsating stars across the HR Diagram. This review describes for non-specialists pulsation modes in stars and discusses a selection of some of the successes already accomplished in asteroseismology.
Excitation of P-Modes in the Sun and Stars
Authors: Stein Robert , Georgobiani Dali , Trampedach Regner , Ludwig Hans-Günter , Nordlund Åke 
Published: March 2016

AbstractP-mode oscillations in the Sun and stars are excited stochasticly by Reynolds stress and entropy fluctuations produced by convection in their outer envelopes. The excitation increases with increasing effective temperature (until envelope convection ceases in the F stars) and also increases with decreasing gravity.
Observational Results of Full-Disc Helioseismology
Authors: New Roger 
Published: March 2016

AbstractEver since the discovery of the low-degree p modes was announced by Claverie et al. (1979), full-disc helioseismology – seismology of the Sun based on the study of sunlight integrated across the entire disc – has contributed very significantly to our understanding of the deep solar interior and the origin and nature of the oscillation modes which probe it. This paper touches on the principal observational techniques used for full-disc helioseismology and outlines key results and their implications.
Large Interstellar and Cometary Biomolecules
Authors: Snyder Lewis E. 
Published: March 2016

AbstractThe relevance of hot molecular cores (HMCs) to the solar nebula has been strengthened as evidence emerges for a hot core phase in low mass star formation regions. Consequently, interferometric studies of large highly saturated molecules of biological interest (biomolecules) in HMCs have been extended to comets. A key goal is the interferometric detection and mapping of large biomolecules, which could be formed along chemical pathways similar to those for HMC species.
Implications of Ice Morphology for Comet Formation
Authors: Collings M. P. , Dever J. W. , McCoustra M. R. S. , Fraser H. J. 
Published: March 2016

AbstractLaboratory surface science under ultra-high vacuum (UHV) conditions allows us to simulate the growth of ices in astrophysical environments. Using the techniques of temperature programmed desorption (TPD), reflection-absorption infrared spectroscopy (RAIRS) and micro-balance methods, we have studied binary ice systems consisting of water (H2O) and variety of other species including carbon monoxide (CO), at astrophysically relevant conditions of temperature and pressure. We present results that demonstrate that the morphology of water ice has an important influence on the behavior of such systems, by allowing processes such as diffusion and trapping that can not be understood through a knowledge of the binding energies of the species alone. Through an understanding of the implications of water ice morphology on the behavior of ice mixtures in the interstellar environment, additional constraints can be placed on the thermodynamic conditions and ice compositions during comet formation.
Models of Collapsing Clouds and Star-Forming Regions as Analogs of the Solar Nebula
Authors: Caselli Paola 
Published: March 2016

AbstractTo fully understand the formation and the evolution of the Solar Nebula, the physical and chemical characteristics of the “pre-solar” cloud should be known. Here, I review recent findings on the study of starless and pre-stellar cores, pointing out the importance of molecular freeze out in the chemical and dynamical evolution of star forming regions.
The Structure of the Solar Nebula From Cometary Composition
Authors: Bockelée-Morvan D. , Hersant F. , Gautier D. , Huré J.-M. 
Published: March 2016

AbstractThis paper presents an interpretation of cometary compositional data in the frame of an evolutionary 2D turbulent model of the Solar Nebula: D/H ratios, crystalline silicates and N2/CO deficiency.