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Cepheid parallaxes and the Hubble constant
van Leeuwen, Floor; Whitelock, Patricia A.; Feast, Michael W. +1 more
Revised Hipparcos parallaxes for classical Cepheids are analysed together with 10 Hubble Space Telescope (HST)-based parallaxes. In a reddening-free V, I relation we find that the coefficient of logP is the same within the uncertainties in our Galaxy as in the Large Magellanic Cloud (LMC), contrary to some previous suggestions. Cepheids in the inn…
Continuous Plasma Outflows from the Edge of a Solar Active Region as a Possible Source of Solar Wind
Golub, Leon; DeLuca, Edward E.; Harra, Louise K. +18 more
The Sun continuously expels a huge amount of ionized material into interplanetary space as the solar wind. Despite its influence on the heliospheric environment, the origin of the solar wind has yet to be well identified. In this paper, we report Hinode X-ray Telescope observations of a solar active region. At the edge of the active region, locate…
The Stellar Mass Tully-Fisher Relation to z = 1.2 from AEGIS
Weiner, Benjamin J.; Faber, S. M.; Lotz, Jennifer M. +12 more
We combine newly measured rotation velocities, velocity dispersions, and stellar masses to construct stellar mass Tully-Fisher relations (M*TFRs) for 544 galaxies with strong emission lines at 0.1<z<1.2 from the All-Wavelength Extended Groth Strip International Survey (AEGIS) and the Deep Extragalactic Evolutionary Probe 2 (DEEP2)…
Present and Future Observing Trends in Atmospheric Magnetoseismology
Erdélyi, R.; Banerjee, D.; O'Shea, E. +1 more
With modern imaging and spectral instruments observing in the visible, EUV, X-ray, and radio wavelengths, the detection of oscillations in the solar outer atmosphere has become a routine event. These oscillations are considered to be the signatures of a wave phenomenon and are generally interpreted in terms of magnetohydrodynamic (MHD) waves. With…
Hubble Space Telescope time-series photometry of the planetary transit of HD 189733: no moon, no rings, starspots
Bouchy, F.; Moutou, C.; Pont, F. +7 more
We monitored three transits of the giant gas planet around the nearby K dwarf HD 189733 with the ACS camera on the Hubble Space Telescope. The resulting very-high accuracy lightcurve (signal-to-noise ratio near 15 000 on individual measurements, 35 000 on 10-min averages) allows a direct geometric measurement of the orbital inclination, radius rat…
Virtis: An Imaging Spectrometer for the Rosetta Mission
Langevin, Y.; Rauer, H.; Bellucci, G. +42 more
The VIRTIS (Visual IR Thermal Imaging Spectrometer) experiment has been one of the most successful experiments built in Europe for Planetary Exploration. VIRTIS, developed in cooperation among Italy, France and Germany, has been already selected as a key experiment for 3 planetary missions: the ESA-Rosetta and Venus Express and NASA-Dawn. VIRTIS o…
The Variable Rotation Period of the Inner Region of Saturn’s Plasma Disk
Gurnett, D. A.; Persoon, A. M.; Dougherty, M. K. +4 more
We show that the plasma and magnetic fields in the inner region of Saturn’s plasma disk rotate in synchronism with the time-variable modulation period of Saturn’s kilometric radio emission. This relation suggests that the radio modulation has its origins in the inner region of the plasma disk, most likely from a centrifugally driven convective ins…
Evolution of the solar wind proton temperature anisotropy from 0.3 to 2.5 AU
Maksimovic, Milan; Landi, Simone; Hellinger, Petr +5 more
We report an analysis of the proton temperature anisotropy evolution from 0.3 to 2.5 AU based on the Helios and Ulysses observations. With increasing distance the fast wind data show a path in the parameter space (β $\parallel$ p , T $\perp$ p /T $\parallel$ p ). The first part of the trajectory is well describe…
Reconnection of Magnetic Fields: Magnetohydrodynamics and Collisionless Theory and Observations
Priest, E. R.; Birn, J.
Preface; Part I. Introduction: 1.1 The Sun E. R. Priest; 1.2 Earth's magnetosphere J. Birn; Part II. Basic Theory of MHD Reconnection: 2.1 Classical theory of two-dimensional reconnection T. G. Forbes; 2.2 Fundamental concepts G. Hornig; 2.3 Three-dimensional reconnection in the absence of magnetic null points G. Hornig; 2.4 Three-dimensional reco…
Cosmological constraints from the 100-deg2 weak-lensing survey
Hoekstra, Henk; Heymans, Catherine; Mellier, Yannick +7 more
We present a cosmic shear analysis of the 100-deg2 weak-lensing survey, combining data from the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys. Spanning ~100 deg2, with a median source redshift z~ 0.78, this combined survey allows us to place tight joint constraints on the matter density parameter Ωm, and the …