Tracers of Chromospheric Structure I: Observations of Ca II K and H alpha in M DwarfsWe report on our observing program to capture simultaneous spectra of Ca II and Balmer lines in a sample of nearby M3 dwarfs. Our goal is to investigate the chromospheric temperature structure…Lucianne M. Walkowicz, Suzanne L. Hawley·Nov 11, 2008SaveLearn
The Galactic Stellar DiscThe study of the Milky Way stellar discs in the context of galaxy formation is discussed. In particular we explore the properties of the Milky Way disc using a new sample of about 550 dwarf stars for…S. Feltzing, T. Bensby·Nov 11, 2008SaveLearn
An 80-kpc Lyman-alpha halo around a high redshift type-2 QSOWe announce the discovery of an extended emission line region associated with a high redshift type-2 QSO. The halo, which was discovered in our new wide-field narrow-band survey, resides at z = 2.85…Daniel J. B. Smith, Matt J. Jarvis, Chris Simpson et al.·Nov 11, 2008SaveLearn
Metal-Absorption Column Densities in Fast Radiative ShocksIn this paper we present computations of the integrated metal-ion column densities produced in the post-shock cooling layers behind fast, radiative shock-waves. For this purpose, we have constructed…Orly Gnat, Amiel Sternberg·Nov 11, 2008SaveLearn
Magnetic layers and neutral points near rotating black holeMagnetic layers are narrow regions where the field direction changes sharply. They often occur in the association with neutral points of the magnetic field. We show that an organised field can…V. Karas, O. Kopacek·Nov 11, 2008SaveLearn
Non-steady Accretion in ProtostarsObservations indicate that mass accretion rates onto low-mass protostars are generally lower than the rates of infall to their disks; this suggests that much of the protostellar mass must be accreted…Zhaohuan Zhu, Lee Hartmann, Charles Gammie·Nov 11, 2008SaveLearn
Revisiting the formation History of the minor-axis dust lane galaxy NGC1947In this paper we present a detailed study of the peculiar early-type galaxy NGC1947. The main goal of this work is to constrain the dynamical status and the formation history of NGC1947 by comparing…M. Spavone, E. Iodice, R. Calvi et al.·Nov 11, 2008SaveLearn
The X-Ray Environment During the Epoch of Terrestrial Planet Formation: Chandra Observations of h PerseiWe describe Chandra/ACIS-I observations of the massive ~ 13--14 Myr-old cluster, h Persei, part of the famous Double Cluster (h and chi Persei) in Perseus. Combining the list of Chandra-detected…Thayne Currie, Nancy Remage Evans, Brad Spitzbart et al.·Nov 11, 2008SaveLearn
Factor analysis of the long gamma-ray burstsWe study statistically 197 long gamma-ray bursts, detected and measured in detail by the BATSE instrument of the Compton Gamma-Ray Observatory. In the sample 10 variables, describing for any burst…Z. Bagoly, L. Borgonovo, A. Meszaros et al.·Nov 11, 2008SaveLearn
Impact of low-frequency p modes on the inversions of the internal rotation of the SunWe used the m-averaged spectrum technique ("collapsogram") to extract the low-frequency solar p-mode parameters of low- and intermediate-angular degrees (l ≤ 35) in long time series of…D. Salabert, A. Eff-Darwich, R. Howe et al.·Nov 11, 2008SaveLearn
Six White Dwarfs with Circumstellar SilicatesSpitzer Space Telescope spectra reveal 10 micron silicate emission from circumstellar dust orbiting six externally-polluted white dwarfs. Micron-size glasses with an olivine stoichiometry can account…M. Jura, J. Farihi, B. Zuckerman·Nov 11, 2008SaveLearn
The data mining: An analysis of 20 eclipsing binary light-curves observed by the INTEGRAL/OMCTwenty eclipsing binaries were selected for an analysis from a huge database of observations made by the INTEGRAL/OMC camera. The photometric data were processed and analyzed, resulting in a first…P. Zasche·Nov 11, 2008SaveLearn
Are AGN the Best Factories for High Energy Particles and Photons?The main properties of AGN are reviewed, focussing on the accretion process and on the question of whether AGN are the best factories of ultra high energy particles and photons. I recall the large…Suzy Collin·Nov 11, 2008SaveLearn
Spectropolarimetery of umbral fine structures from Hinode: Evidence for magnetoconvectionWe present spectropolarimetric analysis of umbral dots and a light bridge fragment that show dark lanes in G-band images. Umbral dots show upflow as well as associated positive Stokes V area…Lokesh Bharti, Chandan Joshi, S. N. A. Jaaffrey et al.·Nov 11, 2008SaveLearn
A Global Study of X-ray BinariesWe present preliminary results on a global study of X-ray binaries using 14 Ms of data from the Rossi X-ray Timing Explorer satellite. Our initial study on GX 339-4 is recapped as an introduction to…Robert Dunn, Rob Fender, Elmar Koerding et al.·Nov 11, 2008SaveLearn
Effect of Central Mass Concentration on the Formation of Nuclear Spirals in Barred GalaxiesWe have performed smoothed particle hydrodynamics (SPH) simulations to study the response of the central kiloparsec region of a gaseous disk to the imposition of nonaxisymmetric bar potentials. The…Parijat Thakur, H. B. Ann, Ing-Guey Jiang·Nov 11, 2008SaveLearn
The nearby eclipsing stellar system delta Velorum - I. Origin of the infrared excess from VISIR and NACO imaging- Context: The triple stellar system delta Vel system presents a significant infrared excess, whose origin is still being debated. A large infrared bow shock has been discovered using Spitzer/MIPS…Pierre Kervella, Frédéric Thévenin, Monika Petr-Gotzens·Nov 11, 2008SaveLearn
MAGIC upper limits to the VHE gamma-ray flux of 3C454.3 in high emission stateWe report upper limits to the very high energy flux (E>100 GeV) of the flat spectrum radio quasar 3C454.3 (z=0.859) derived by the Cherenkov telescope MAGIC during the high states of July/August and…H. Anderhub, S. Vercellone, I. Donnarumma et al.·Nov 11, 2008SaveLearn
Simulating weak lensing on CMB mapsWe present a fast, arbitrarily accurate method to simulate the effect of gravitational lensing of the Cosmic Microwave Background anisotropies and polarization fields by large scale structures. We…S. Basak, S. Prunet, K. Benabed·Nov 11, 2008SaveLearn
Tests of AMiBA Data IntegrityWe describe methods used to validate data from the Y.T. Lee Array for Microwave Background Anisotropy (AMiBA), an interferometric array designed to measure the Sunyaev-Zel'dovich effect and the…Hiroaki Nishioka, Fu-Cheng Wang, Jiun-Huei Proty Wu et al.·Nov 11, 2008SaveLearn
A highly collimated jet from the low mass proto-star NGC1333 IRAS 4BWe imaged the protostars of the nearby region NGC1333 IRAS 4 in the water maser line at 22.2 GHz by using the VLBA in phase referencing at milliarcsecond scale over four epochs spaced by one month to…J. -F. Desmurs, C. Codella, J. Santiago-Garcia et al.·Nov 11, 2008SaveLearn
Revealing the fastest component of the DG Tau outflow through X-raysSome T Tauri stars show a peculiar X-ray spectrum that can be modelled by two components with different absorbing column densities. We seek to explain the soft X-ray component in DG Tau, the best…H. M. Guenther, S. P. Matt, Z. -Y. Li·Nov 11, 2008SaveLearn
A Flaring X-ray Source with an Halpha-bright Counterpart toward the SMCWe report the discovery of a flaring X-ray source with an optical counterpart with Halpha emission and red-excess, in the direction of the SMC. A 100 ksec X-ray observation with Chandra detected a…Silas Laycock, Jeremy J. Drake·Nov 11, 2008SaveLearn
Discovery of photospheric CaX emission lines in the far-UV spectrum of the hottest known white dwarf (KPD0005+5106)For the first time, we have identified photospheric emission lines in the far-UV spectrum of a white dwarf. They were discovered in the Far Ultraviolet Spectroscopic Explorer spectrum of the hot…K. Werner, T. Rauch, J. W. Kruk·Nov 11, 2008SaveLearn
The VVDS-VLA Deep Field - IV: Radio-optical properties(abridged) We use the 1.4 GHz VIMOS-VLA Deep Survey and the optical VVDS and the CFHT-LS to compare the properties of radio loud galaxies with respect to the whole population of optical galaxies. The…S. Bardelli, E. Zucca, M. Bolzonella et al.·Nov 11, 2008SaveLearn