bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamical Evolution of Globular Cluster Systems
Authors: Vesperini E.
Published: March 2016

I 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

We 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

We 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.
Abundances in LMC and SMC Globular Clusters
Authors: Johnson Jennifer A. , Ivans Inese I. , Stetson Peter B. , Hesser James E. , Bolte Michael
Published: March 2016

We present results for abundances in four old Magellanic Cloud clusters based on high-resolution spectroscopy of individual giants.
Globular Cluster Formation in Galaxy Mergers
Authors: Li Yuexing , Mac Low Mordecai-Mark , Klessen Ralf S.
Published: March 2016

We 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

Even 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

I 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

We 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

A 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

With 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

P-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

Ever 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.
A Review of the Distance and Structure of the Large Magellanic Cloud
Authors: Alves David R.
Published: March 2016

The debate about the distance to the Large Magellanic Cloud (LMC) has an epic history full of controversial and dramatic claims (i.e., see review by Walker 2003), and yet in recent years a standard distance modulus has emerged due primarily to the completion of the Hubble Space Telescope (HST) Key Project to measure the Hubble constant (Preedman et al. 2001). The adopted standard distance modulus,µ0 = 18.5±0.1 mag, yields H0 = 71±10 km s−1 Mpc−1 (total error) in excellent agreement with that derived from the Wilkinson Microwave Anisotropy Probe: H0 72±5 km s−1 Mpc−1 (Spergel et al. 2003), which lends considerable support to its accuracy.
Direct DEBs in M31 and M33
Authors: Macri Lucas M.
Published: March 2016

The DIRECT project (as in “direct distances”) started in 1996 with the long-term goal of obtaining distances to two important galaxies in the cosmological distance ladder – M31 and M33 – using detached eclipsing binaries (DEBs) and Cepheids. These two nearby galaxies are the stepping stones in most of the current effort to understand the evolving universe at large scales. Not only are they essential to the calibration of the extragalactic distance scale, but they also constrain population synthesis models for early galaxy formation and evolution. However, accurate distances are essential to make these calibrations free from large systematic uncertainties.
Eclipsing Spectroscopic Binaries in the SMC
Authors: Hilditch Ron W. , Harries Tim J. , Howarth Ian D.
Published: March 2016

The OGLE survey of the SMC has discovered ~1500 eclipsing binaries thereby providing an excellent platform to study the evolution of close binary systems through case A and case B mass-exchange processes. The complementary spectroscopic radial-velocity studies of these binaries are now in progress and are revealing many interesting systems which challenge current theoretical models of close binary star evolution. These studies also provide excellent direct determinations of distances to these binary stars leading to an improved understanding of the mean distance to the SMC and its 3-D structure. Comparisons between these binary-star distances and other methods of determining the mean distance to the SMC will also be made.
Contact Binaries of the W UMa Type as Distance Tracers
Authors: Rucinski Slavek M.
Published: March 2016

Contact binary stars of the W UMa-type (also known as W) are unique objects: The luminosity, produced almost exclusively in the more massive component is efficiently distributed through the common envelope so that the surface brightness is practically identical over the whole visible surface of the binary. Mass ratios are known to span the whole wide range, from almost unity to very small values, as small as q = 0.066. Typically, the primary component provides the luminosity, while both components provide the radiating area. The range of the primary masses is moderate and corresponds to Main Sequence spectral types from middle A to early K and roughly maps into the orbital-period range of about 1.5 days to 0.22 days.
Massive Binaries in the Magellanic Clouds
Authors: Niemela Virpi S.
Published: March 2016

We present results of our ongoing observing program on search and studies of massive stars (O and WR type) in binary systems in our neighbor galaxies, the Magellanic Clouds. Radial velocity orbits are presented for two new binaries, one in the Small Magellanic Cloud and another in the Large Magellanic Cloud, and improved orbits for previously known systems. We compare orbital parameters of selected binaries containing O and WR type components. We also discuss the present status of knowledge for massive binary stars in the Magellanic Clouds and the problems encountered in their orbital studies such as stellar winds the ubiquitous tendency to be born in multiple systems.
Extragalactic Eclipsing Binaries: Astrophysical Laboratories
Authors: Ribas Ignasi
Published: March 2016

Eclipsing binaries (EBs) have long been known for providing accurate stellar fundamental properties, such as masses and radii. These are obtained from the modeling of light and radial velocity curves and, with input data of good quality, uncertainties of a few percent in the components’ physical properties are now routinely achieved. Additionally, a number of other observables are determined for eclipsing binaries using techniques similar to those employed for single stars: Effective temperatures from multi-wavelength photometric analysis and chemical abundances from detailed spectroscopic modeling. Thus, EB systems provide a complete characterization of the physical properties of their components, with the added constraint that both stars should have identical age. Also worth mentioning is the ubiquity of EB systems among all kinds of stars. Main sequence stars, variable stars, giants, supergiants, and compact objects, to name a few, are found as members of EBs. This makes EBs excellent “laboratories” for stellar astrophysics. A number of studies have exploited this fact and carried out detailed analysis of galactic EB systems (e.g. Andersen et al. 1991; Clausen 1991; Claret & Giménez 1993; Schröder et al. 1997; Guinan et al. 2000). A few areas where EBs play a crucial role in astrophysics are stellar structure and evolution, tidal evolution, stellar atmospheres, binary evolution in interactive systems,…
Large Interstellar and Cometary Biomolecules
Authors: Snyder Lewis E.
Published: March 2016

The 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

Laboratory 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.
The Nature of Diatomic Sulfur in Comets
Authors: Boice D. C. , Reylé Céline
Published: March 2016

Diatomic sulfur was first discovered in comets during the close approach to Earth of comet IRAS-Araki-Alcock (C/1983 HI). The spatial distribution of S2 was restricted to within a few hundred kilometers of the nucleus, consistent with S2 being a parent molecule. This molecule has been detected in comets Hyakutake (C/1996 B2), Lee (C/1999 HI), and recently in Ikeya-Zhang (C/2002 CI), leading to the conclusion that S2 is ubiquitous in comets.
Models of Collapsing Clouds and Star-Forming Regions as Analogs of the Solar Nebula
Authors: Caselli Paola
Published: March 2016

To 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

This 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.
The Star Formation History of Damped Lyman-Alpha Systems
Authors: Wolfe Arthur M.
Published: March 2016

The C II* technique for measuring star formation rates (SFRs) in damped Lya systems (DLAs) is described. We measure cooling rates of the gas from the strength of C II* 1335.7 absorption lines, and infer heating rates by assuming the gas is heated by the grain photoelectric mechanism. Since the heating rates depend on the intensity of FUV radiation, we deduce the SFRs per unit area, which are comparable to the value in the Milky Way disk. From DLA statistics we obtain the SFRs per unit comoving volume at z=[1.6,4.5], which are similar to the rates in Lyman Break Galaxies. Implications such as the presence of a two-phase medium, metal production, and feedback processes are described. The model is tested and found to be consistent with observations.
The First Results from “Solar X-ray Spectrometer (SOXS)” Mission
Authors: Jain Rajmal , Dave Hemant , Sreekumar P. , Shah A. B. , Vadher N. M. , Manian K. S. B. , Ubale G. P. , Shah V. M. , Shah K. J. , Kayasth S. L. , Patel V. D. , Kumar Sumit , Deshpande M. R.
Published: March 2016

“Solar X-ray Spectrometer (SOXS)” mission on-board GSAT-2 Indian spacecraft was launched on 08 May 2003 by GSLV-D2 and deployed in geostationery orbit to study the X-ray emission from solar flares with high spectral and temporal resolution. The SOXS consists of two independent payloads viz. SOXS Low Energy Detector (SLD) payload, and SOXS High Energy Detector (SHD) payload. The SLD consists of two solid state detectors Si PIN and CZT, which cover the energy range from 4-60 keV, while the SHD has NaI(Tl)/CsI(Na) sandwiched phoswich detector that covers energy range from 20 keV to 10 MeV. We present very briefly the science objectives and instrumentation of SLD payload. After the successful In-orbit Tests (IOT), the first light was fed into SLD payload on 08 June 2003 when the solar flare was already in progress. We briefly present the first results from the SLD payload.
New Results on X-ray Models and Atomic Data
Authors: Kaastra Jelle S. , Mewe Rolf , Raassen Ton
Published: March 2016

We discuss the most recent developments of the spectral analysis package SPEX. We report on the progress made in updating the atomic data that are used in the spectroscopic code. We also present a set of spectral models that are used for the analysis of high-resolution X-ray spectra of photo-ionized plasmas such as occur in active galactic nuclei. These models include absorption line spectroscopy of photoionized layers. The importance and diagnostic power of inner-shell transitions is shown. We illustrate our results with several examples of observed spectra obtained with the XMM-Newton and Chandra grating spectrometers.
Spectral Modeling with APEC
Authors: Brickhouse Nancy S. , Smith Randall K.
Published: March 2016

The Astrophysical Plasma Emission Code (APEC) collaboration now provides public models for X-ray spectra of collisional equilibrium plasmas. These models facilitate the diagnosis of temperature, density, elemental abundance, charge state, and optical depth. We report benchmarking studies of the APEC models from the Emission Line Project, a project to test these models using high quality stellar coronal spectra. We discuss the implications of the benchmarked atomic data for non-equilibrium collisional models as well. Finally, we discuss the extension of APEC to other applications, such as opacity models for AGN.
NIFS Atomic Numerical Databases
Authors: Murakami Izumi , Kato Takako
Published: March 2016

We have compiled the atomic and molecular numerical databases which are available through internet. The databases provide basic atomic data, such as collisional ionization and excitation cross sections, which are important for modeling and diagnosing astrophysical plasmas.
Central Regions of AGNs Probed by the Neutral Hydrogen
Authors: Morganti Raffaella
Published: March 2016

The physical and kinematical conditions of the gas surrounding an active galactic nucleus (AGN) offer key diagnostics for understanding the processes occurring in the inner few kpc around the nucleus. Neutral hydrogen can give important insights on these regions. Apart from probing the presence of gas in relatively settled conditions (i.e. circumnuclear disks/tori) it can also trace the presence of extreme outflows. Some examples of these phenomena are briefly presented.
ISO Observations of Comets
Authors: Bockelée-Morvan Dominique
Published: March 2016

The Infrared Space Observatory (ISO) offered us the opportunity to observe celestial bodies from 2.4 to 196 microns. A wealth of new results were obtained for comets. Spectroscopic investigations have shown band fluorescence emissions for H2O, CO and CO2, and rotational line emissions for H2O. High resolution spectra of water vapor around 2.7 microns in comets C/1995 01 (Hale-Bopp) and 103P/Hartley 2 have permitted measurement of the water rotational temperature and ortho-to-para ratio. The thermal region of the spectra showed the signatures of crystalline, Mg-rich olivine and emission features attributed to water ice. Broad band photometry of the coma allowed to investigate several properties of cometary dust, such has color temperature, size distribution and production rate. For several comets, it was possible to separate the nuclear and coma contribution in infrared images obtained from the ISO camera. Inferences concerning the nucleus size and albedo were obtained.
High Resolution X-ray Spectroscopy: Is It Interesting? Is It Possible?
Authors: Cash Webster
Published: March 2016

The diffraction grating spectra from Chandra and XMM-Newton have given the astronomical community a huge step forward in x-ray spectroscopy of celestial sources. They have proven the scientific richness of the field. But the spectra have resolution of only 300 to 1000 – low by the standards of the visible and the ultraviolet. We discuss some of the exciting new science that can be addressed if spectral resolution of up to 10,000 (or more) can be achieved in the x-ray. We then show how practical, high efficiency, high resolution x-ray spectrographs can be built for high throughput missions like Constellation-X and XEUS.
The Future for UV Spectroscopy of the ISM at High Resolution
Authors: Jenkins Edward B.
Published: March 2016

In the post-HST era, advanced missions for performing UV spectroscopy must excel in many ways. We must not overlook the importance of high wavelength resolution for investigating absorption lines from gas systems in the Galaxy and beyond. We consider here some basic principles on this topic, both scientific and technical.
Chemistry of Diffuse Clouds and Circumstellar Envelopes
Authors: Lucas Robert
Published: March 2016

We present and review recent millimeter-wave observations with interferometers, in particular, with the Plateau de Bure interferometer, that stress the importance of high-frequency resolution for studying the chemistry of diffuse interstellar clouds and of post main-sequence circumstellar envelopes. The future impact of new instruments, such as the Atacama Large Millimeter and submillimeter Array (ALMA), is also investigated.
Spectral-Line Surveys at Millimeter and Submillimeter Wavelengths: Impact of Spectral Resolution
Authors: Ziurys L. M.
Published: March 2016

Millimeter and submillimeter astronomy has achieved very high spectral resolution (λ/Δλ ≥ 106-107) over the past 20 years. Broad-band spectral-line surveys at these wavelengths have only taken partial advantage of these capabilities. Such surveys could be more effective with an increase in spectral resolution, accompanied by improvement in the stability and bandwidth of spectrometers and the employment of single-sideband detectors.
Deep Searches for High Redshift Molecular Absorption
Authors: Curran S. J. , Webb J. K. , Murphy M. T. , Kuno N.
Published: March 2016

Millimetre-band scans of the frequency space towards optically dim quasars is potentially a highly efficient method for detecting new high red-shift molecular absorption systems. Here we describe scans towards 7 quasars over wide bandwidths (up to 23 GHz) with sensitivity limits sufficient to detect the 4 redshifted absorbers already known. With wider frequency bands, highly efficient searches of large numbers of possibly obscured objects will yield many new molecular absorbers.
CO J = 7 → 6 Emission in the Large Magellanic Cloud
Authors: Kim Sungeun , Walsh Wilfred , Xiao Kecheng , Lane Adair P. , Stark Antony A.
Published: March 2016

We present the first detection of 12CO (J = 7 → 6) emission in the Magellanic Clouds toward the 30 Doradus region using the Antarctic Sub-millimeter Telescope and Remote Observatory (AST/RO).
A Gas and Dust Rich Giant Elliptical Galaxy
Authors: Krause O. , Lisenfeld U. , Klaas U. , Lemke D. , Haas M. , Stickel M.
Published: March 2016

The bolometric luminosity of LFIR = 2×1012 L⊙ makes ISOSS J 15079+7247 one of the most luminous and unusual galaxies detected by the 170 μm ISOPHOT Serendipity Survey (ISOSS). The detection of CO (1-0) emission identifies a giant elliptical galaxy at redshift z = 0.2136 as the counterpart of the FIR source. The derived high gas mass of 3 × 1010 M⊙ favours the picture that the dust emission is associated with this elliptical galaxy. The ultraluminous IR emission can be explained by a hidden starburst in the center of the elliptical. This is supported by the strength of non-thermal radio continuum emission. The huge dust mass of 5×108 M⊙ corresponds to a visual extinction of AV ~ 1000 mag, being consistent with the non-detection of any signatures of a strong starburst in ISOSS J 15079+7247 in optical spectra.
The Abundant Irregular Satellites of the Giant Planets
Authors: Sheppard Scott S. , Jewitt David C.
Published: March 2016

Irregular satellites have eccentric orbits that can be highly inclined or even retrograde relative to the equatorial planes of their planets. These objects cannot have formed by circumplanetary accretion as did the regular satellites which follow un-inclined, nearly circular, pro-grade orbits. Instead, they are likely products of early capture from heliocentric orbit. The study of the irregular satellites provides a unique window on processes operating in the young solar system. Recent discoveries around Jupiter (45 new satellites), Saturn (13), Uranus (9), and Neptune (5) have almost increased the number of known irregular satellites by a factor of ten and suggest that the gas and ice giant planets all have fairly similar irregular satellite systems. Dynamical groupings were most likely produced by collisional shattering of precursor objects after capture by their planets. Jupiter is considered as a case of special interest. Its proximity allows us to probe the fainter, smaller irregular satellites to obtain large population statistics in order to address the questions of planet formation and capture.
Is Amalthea a Captured Trojan Asteroid of Jupiter?
Authors: Prentice Andrew J. R.
Published: March 2016

The Galileo spacecraft has found Jupiter’s inner regular moon Amalthea to be a porous assemblage of rock and ice. This and other factors point to Amalthea having first condensed in a solar orbit.
Charon/Pluto Light Ratio
Authors: Clancy K. B. , Elliot J. L. , Person M. J.
Published: March 2016

Prediction of the occultations of the stars P126 and P131.1 by Pluto on 2002 July 20 (UT) and August 21 (UT), respectively (Clancy et al. 2002, BAAS 34, 1212) involved astrometric data sets spanning more than three months that were acquired on several telescopes. Pluto’s position in each frame was determined relative to a UCAC astrometric reference network (Zacharias et al. 2000, AJ 120, 2131) with a dual-source point-spread function (PSF) model that was fit to the blended Pluto-Charon image. The relative position of Charon from Pluto was fixed in the PSF using values from the JPL Horizons ephemeris, and the light ratio fixed at values from resolved photometric observations of Pluto and Charon presented in Buie, Tholen, and Wasserman (1993, Icarus 125, 233). Although the final predictions proved to be quite accurate (see http://occult.mit.edu/research/occultations/Candidates/Predictions/P126.html and http://occult.mit.edu/research/occultations/Candidates/Predictions/P131.1.html), empirical corrections were made to the offset of Pluto from its ephemeris. These corrections were based on the residuals of Pluto’s measured position from its ephemeris, which were sinusoidal. The consistency of the fitted residual phase and amplitude between all prediction data sets implies either an incorrect Charon to Pluto mass ratio was used for calculating Charon’s ephemeris, or that we used incorrect Charon/Pluto light ratios in this reduction. Resolved images of Pluto-Charon were taken over a period of six days (2003 April) in nine filters at the Magellan 6.5-m Clay telescope in order to uncover the cause of these residuals. Combined with other Magellan Pluto frames taken in 2001 and 2002, the images were fit with a dual-source PSF model. The Charon/Pluto light ratio determined from the PSF modeling was then plotted against orbital phase and fit with a sinusoidal model for each filter. A strong trend with wavelength was found for the mean light ratio of Charon to Pluto. This trend partially explains the residuals found, as the astrograph and CTIO data were taken in a filter of mean wavelength ~720nm, whereas the Buie et al. resolved light curve was obtained in the F555W filter of mean wavelength ~537 nm. This trend can account for 0.026” of the 0.053” residual amplitude. However, if the only other effect were an erroneous Charon/Pluto mass ratio, the remaining residual would imply a mass ratio of 0.086 rather than 0.120 (as used in the JPL Horizons ephemeris). A value of 0.086 does not agree with recent mass ratio measurements (0.157 ± 0.003 by Young et al. 1994, Icarus 108, 186; 0.124 ± 0.008 by Null and Owen 1996, AJ, 111, 1368; and 0.122 ± 0.008 by Olkin et al. 2003, Icarus 164, 254), thus more work must be done in these analyses to understand the cause of these residuals. This work was funded at MIT in part by NASA Grant NAG5-10444 and NSF Grant AST-0073447.
Origin and Distribution of Water Amongst the Inner Planets
Authors: Prentice Andrew J. R.
Published: March 2016

A new model for the origin and bulk chemical composition of the inner planets, especially for their water content, is reported.
Winds in Venus’ Lower Mesosphere
Authors: Widemann Thomas , Lellouch Emmanuel
Published: March 2016

Dynamics of Venus’ mesosphere (70-110 km) is characterized by the coexistence of two different wind regimes: (1) between 70 and 85 km the vertical amplitude decrease of Venus’ zonal retrograde super-rotation; (2) between 85 and 110 km, a stable, sub-solar to anti-solar (SSAS) flow, driven by solar EUV heating. On July 7-14, 2001 and July 31 – August 4, 2002 we observed Venus with the Aurélie spectrometer on the 1.5-m telescope at Observatoire de Haute-Provence, France. The spectra cover the visible 8660-8730 Å range, in the 5v3 band of 12C16O2, at a resolving power of about 120,000. Seven regions were observed on Venus’ illuminated side at ~ 75° phase angle. About 28 lines from the P and R branches of the 5v3 band were detected and used for wind velocity measurements with an accuracy of 15 to 25 ms-1.
Antarctic Cosmic Ray Astronomy
Authors: Duldig Marc
Published: March 2016

Cosmic ray observations related to Antarctica commenced in the austral summer of 1947-48 from sub-Antarctic Heard and Macquarie Islands and from the HMAS Wyatt Earp. Muon telescope observations from Mawson station, Antarctica, followed from 1955. The International Geophysical Year was the impetus for the installation of a number of neutron monitors around Antarctica, observing the lowest energy cosmic rays accessible by ground based instruments. In 1971 a new observatory was built at Mawson including the only underground muon telescope system at polar latitudes in either hemisphere. Over more than half a century, cosmic ray astronomy has been undertaken from Antarctica and its surrounding regions and these observations have been critical to our growing understanding of the heliosphere.
Beyond Dome C
Authors: Storey J.W.V. , Ashley M.C.B. , Burton M.G. , Lawrence J.S.
Published: March 2016

A well-focused research program over the past decade has shown that the South Pole has many remarkable characteristics that are particularly favorable for astronomy. These include the very cold, dry atmosphere and the vanishingly small free-air turbulence. Dome C, site of the new French/Italian station Concordia, has all of these attributes plus the added advantage of very low ground-level wind speeds. Higher on the plateau, locations such as the 4200 m high Dome A may well represent the ultimate ground based astronomical observing sites.
Helioseismology from South Pole: Past, Present and Future
Authors: Jefferies Stuart M.
Published: March 2016

The austral summer of 2002/03 marked the beginning of a new era for helioseismology from South Pole with the running of an experiment to seismically probe the solar atmosphere.
Earth as an Extrasolar Planet: South Pole Advantages
Authors: Traub Wesley A. , Stark Antony A. , Jucks Kenneth W. , Kilston Steven , Turner Edwin L. , Seager Sara
Published: March 2016

We could observe the Earth as an extra-solar planet, viewing Earthshine on the dark side of the Moon, at the Pole, in winter.
Addressing Confusion in Double Star Nomenclature: The Washington Multiplicity Catalog
Authors: Hartkopf William I. , Mason Brian D.
Published: March 2016

The Washington Multiplicity Catalog (WMC) project is an effort to address the often conflicting nomenclature schemes used by astronomers in different fields of double and multiple star research, by compiling a catalog of all known binary and multiple systems, then assigning a consistent (insofar as possible) component designation to each component. Components are treated in the same manner whether stellar or sub-stellar (e.g., brown dwarf, exosolar planet) in nature. This effort was begun shortly before the 2000 IAU General Assembly in Manchester, UK. A sample version of the planned catalog was presented at IAU Colloquium 191, held in Mérida, México in February 2003, and a modified version of this sample will be presented at the July 2003 GA in Sydney, Australia. Finally, if the nomenclature and catalog format are agreed upon, a full-sky version of the catalog will be created in time for the 2006 GA in Prague.
The Viewpoint from Commission 40
Authors: Manchester Richard N.
Published: March 2016

Although Very Long Baseline Interferometry has resolved a few binary stellar systems, pulsars provide the main source of binary and multiple stars through radio astronomy techniques. There are about 85 binary pulsars and two multiple systems known. Currently there is no formal system of designating these companions.
Astronomy Education Research Down Under
Authors: Broadfoot John M. , Ginns Ian S.
Published: March 2016

There are many problems associated with the teaching and learning of astronomy that require further investigation (Taylor k, Barker 2000). Students’ difficulties with visualization, mental modeling and conceptual restructuring have been reported by a number of researchers. Aspects of these important areas of research are examined in the paper. However, there has been limited focused research in the specific area of astronomy teaching (Taylor & Barker 2000; Treagust & Smith 1989). For example, the value of strategies that engage students in challenging their prior beliefs and intuitive ideas, thus enabling them to perceive patterns and grapple with frame of reference problems, and construct acceptable models of celestial phenomena, must be assessed. Such strategies might incorporate or re-enact historical discoveries (Noble 1999) thus engaging students in thinking about astronomical phenomena from an intuitive position.
A Contemporary Review of K-16 Astronomy Education Research
Authors: Bailey Janelle M. , Slater Timothy F.
Published: March 2016

Astronomy education research (AER) uses the systematic techniques honed in science education and physics education research to understand what and how students learn about astronomy, and determine how instructors can create more productive learning environments for their students. A recent review of the literature in this area revealed a number of articles that could be classified into four major categories: research into student understanding, research on instructional methods, research on teacher understanding, and descriptions of curriculum materials.
Implementing the Astronomy Education Research
Authors: Fucili Leonarda
Published: March 2016

I think there is nothing like the study of astronomy to capture the imaginations of our students, to make them understand phenomena, and to introduce them to the fundamental ideas and methods of science and mathematics. In my presentation, I will examine my research on effective teaching and learning of astronomy at the elementary school level, and how I have implemented my research in my work with students, teachers, and curriculum.
Astronomy, Pseudoscience, and Rational Thinking
Authors: Narlikar Jayant V.
Published: March 2016

In 1944, three years before India became independent of the British rule, Jawaharlal Nehru wrote in his now famous book Discovery of India: ”The impact of science and the modern world have brought a greater appreciation of facts, a more critical faculty, a weighing of evidence, a refusal to accept tradition merely because it is tradition”. But even today it is strange how we suddenly become overwhelmed by tradition, and the critical faculties of even intelligent people cease to function. He then went on to express the hope that ”Only when we are politically and economically free will the mind function normally and critically”.
Explaining medical disputes in Chinese public hospitals: the doctor–patient relationship and its implications for health policy reforms
Authors: He Alex Jingwei , Qian Jiwei
Published: March 2016

In recent years China has witnessed a surge in medical disputes, including many widely reported violent riots, attacks, and protests in hospitals. This is the result of a confluence of inappropriate incentives in the health system, the consequent distorted behaviors of physicians, mounting social distrust of the medical profession, and institutional failures of the legal framework. The detrimental effects of the damaged doctor–patient relationship have begun to emerge, calling for rigorous study and serious policy intervention. Using a sequential exploratory design, this article seeks to explain medical disputes in Chinese public hospitals with primary data collected from Shenzhen City. The analysis finds that medical disputes of various forms are disturbingly widespread and reveals that inappropriate internal incentives in hospitals and the heavy workload of physicians undermine the quality of clinical encounters, which easily triggers disputes. Empirically, a heavy workload is associated with a larger number of disputes. A greater number of disputes are associated with higher-level hospitals, which can afford larger financial settlements. The resolution of disputes via the legal channel appears to be unpopular. This article argues that restoring a healthy doctor–patient relationship is no less important than other institutional aspects of health care reform.
Stigma towards people with mental disorders and its components – a perspective from multi-ethnic Singapore
Authors: Subramaniam M. , Abdin E. , Picco L. , Pang S. , Shafie S. , Vaingankar J. A. , Kwok K. W. , Verma K. , Chong S. A.
Published: March 2016

Aims.

The current study aimed to: (i) describe the extent of overall stigma as well as the differences in stigma towards people with alcohol abuse, dementia, depression, schizophrenia and obsessive compulsive disorder, as well as (ii) establish the dimensions of stigma and examine its correlates, in the general population of Singapore, using a vignette approach.

Methods.

Data for the current study came from a larger nation-wide cross-sectional study of mental health literacy conducted in Singapore. The study population comprised Singapore Residents (Singapore Citizens and Permanent Residents) aged 18–65 years who were living in Singapore at the time of the survey. All respondents were administered the Personal and Perceived scales of the Depression Stigma scale and the Social Distance scale to measure personal stigma and social distance, respectively. Weighted mean and standard error of the mean were calculated for continuous variables, and frequencies and percentages for categorical variables. Exploratory structural equation modelling and confirmatory factor analysis were used to establish the dimensions of stigma. Multivariable linear regressions were conducted to examine factors associated with each of the stigma scale scores.

Results.

The mean age of the respondents was 40.9 years and gender was equally represented (50.9% were males). The findings from the factor analysis revealed that personal stigma formed two distinct dimensions comprising ‘weak-not-sick’ and ‘dangerous/unpredictable’ while social distance stigma items loaded strongly into a single factor. Those of Malay and Indian ethnicity, lower education, lower income status and those who were administered the depression and alcohol abuse vignette were significantly associated with higher weak-not-sick scores. Those of Indian ethnicity, 6 years of education and below, lower income status and those who were administered the alcohol abuse vignette were significantly associated with higher dangerous/unpredictable scores. Those administered the alcohol abuse vignette were associated with higher social distance scores.

Conclusion.

This population-wide study found significant stigma towards people with mental illness and identified specific groups who have more stigmatising attitudes. The study also found that having a friend or family member with similar problems was associated with having lower personal as well as social distance stigma. There is a need for well-planned and culturally relevant anti-stigma campaigns in this population that take into consideration the findings of this study.
Parp mutations protect against mitochondrial dysfunction and neurodegeneration in a PARKIN model of Parkinson’s disease
Authors: Lehmann S , Costa A C , Celardo I , Loh S H Y , Martins L M
Published: March 2016

The co-enzyme nicotinamide adenine dinucleotide (NAD+) is an essential co-factor for cellular energy generation in mitochondria as well as for DNA repair mechanisms in the cell nucleus involving NAD+-consuming poly (ADP-ribose) polymerases (PARPs). Mitochondrial function is compromised in animal models of Parkinson’s disease (PD) associated with PARKIN mutations. Here, we uncovered alterations in NAD+salvage metabolism inDrosophila parkinmutants. We show that a dietary supplementation with the NAD+precursor nicotinamide rescues mitochondrial function and is neuroprotective. Further, by mutatingParpinparkinmutants, we show that this increases levels of NAD+and its salvage metabolites. This also rescues mitochondrial function and suppresses dopaminergic neurodegeneration. We conclude that strategies to enhance NAD+levels by administration of dietary precursors or the inhibition of NAD+-dependent enzymes, such as PARP, that compete with mitochondria for NAD+could be used to delay neuronal death associated with mitochondrial dysfunction.
Tuning the photo-response in monolayer MoS2 by plasmonic nano-antenna
Authors: Li Jiu , Ji Qingqing , Chu Saisai , Zhang Yanfeng , Li Yan , Gong Qihuang , Liu Kaihui , Shi Kebin
Published: March 2016

Monolayer molybdenum disulfide (MoS2) has recently attracted intense interests due to its remarkable optical properties of valley-selected optical response, strong nonlinear wave mixing and photocurrent/photovoltaic generation and many corresponding potential applications. However, the nature of atomic-thin thickness of monolayer MoS2 leads to inefficient light-matter interactions and thereby hinders its optoelectronic applications. Here we report on the enhanced and controllable photo-response in MoS2 by utilizing surface plasmonic resonance based on metallic nano-antenna with characteristic lateral size of 40 × 80 nm. Our nano-antenna is designed to have one plasmonic resonance in the visible range and can enhance the MoS2 photoluminescence intensity up to 10 folds. The intensity enhancement can be effectively tuned simply by the manipulation of incident light polarization. In addition, we can also control the oscillator strength ratio between exciton and trion states by controlling polarization dependent hot carrier doping in MoS2. Our results demonstrate the possibility in controlling the photo-response in broad two-dimensional materials by well-designed nano-antenna and facilitate its coming optoelectronic applications.
Genome-wide significant results identified for plasma apolipoprotein H levels in middle-aged and older adults
Authors: Mather Karen A. , Thalamuthu Anbupalam , Oldmeadow Christopher , Song Fei , Armstrong Nicola J. , Poljak Anne , Holliday Elizabeth G. , McEvoy Mark , Kwok John B. , Assareh Amelia A. , Reppermund Simone , Kochan Nicole A. , Lee Teresa , Ames David , Wright Margaret J. , Trollor Julian N. , Schofield Peter W. , Brodaty Henry , Scott Rodney J. , Schofield Peter R. , Attia John R. , Sachdev Perminder S.
Published: March 2016

Apolipoprotein H (ApoH) is a multi-functional plasma glycoprotein that has been associated with negative health outcomes. ApoH levels have high heritability. We undertook a genome-wide association study of ApoH levels using the largest sample to date and replicated the results in an independent cohort (total N = 1,255). In the discovery phase, a meta-analysis of two cohorts, the Sydney Memory and Ageing Study (Sydney MAS) and the Older Australian Twins Study (OATS) (n = 942) revealed genome-wide significant results in or near the APOH gene on chromosome 17 (top SNP, rs7211380, p = 1 × 10−11). The results were replicated in an independent cohort, the Hunter Community Study (p < 0.002) (n = 313). Conditional and joint analysis (COJO) confirmed the association of the chromosomal 17 region with ApoH levels. The set of independent SNPs identified by COJO explained 23% of the variance. The relationships between the top SNPs and cardiovascular/lipid/cognition measures and diabetes were assessed in Sydney MAS, with suggestive results observed for diabetes and cognitive performance. However, replication of these results in the smaller OATS cohort was not found. This work provides impetus for future research to better understand the contribution of genetics to ApoH levels and its possible impacts on health.
‘Crystal Genes’ in Metallic Liquids and Glasses
Authors: Sun Yang , Zhang Feng , Ye Zhuo , Zhang Yue , Fang Xiaowei , Ding Zejun , Wang Cai-Zhuang , Mendelev Mikhail I. , Ott Ryan T. , Kramer Matthew J. , Ho Kai-Ming
Published: March 2016

We analyze the underlying structural order that transcends liquid, glass and crystalline states in metallic systems. A genetic algorithm is applied to search for the most common energetically favorable packing motifs in crystalline structures. These motifs are in turn compared to the observed packing motifs in the actual liquid or glass structures using a cluster-alignment method. Using this method, we have revealed the nature of the short-range order in Cu64Zr36 glasses. More importantly, we identified a novel structural order in the Al90Sm10 system. In addition, our approach brings new insight into understanding the origin of vitrification and describing mesoscopic order-disorder transitions in condensed matter systems.