Search Publications
Observations of turbulence within reconnection jet in the presence of guide field
André, M.; Vaivads, A.; Sahraoui, F. +8 more
We present the first comprehensive observations of turbulence properties within high speed reconnection jet in the plasma sheet with moderate guide field. The power spectral density index is about -1.73 in the inertial range, and follows the value of -2.86 in the ion dissipation range. The turbulence is strongly anisotropic in the wave-vector spac…
Observations and simulations of longitudinal oscillations of an active region prominence
Chen, P. F.; Zhang, Q. M.; Xia, C. +1 more
Context. Filament longitudinal oscillations have been observed in Hα observations of the solar disk.
Aims: We intend to find an example of the longitudinal oscillations of a prominence, where the magnetic dip can be seen directly, and examine the restoring force of this type of oscillations.
Methods: We carry out a multiwavelength data a…
COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses. X. Modeling based on high-precision astrometry of a sample of 25 lensed quasars: consequences for ellipticity, shear, and astrometric anomalies
Magain, P.; Meylan, G.; Courbin, F. +2 more
Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant H0 based on the so-called time-delay technique, (ii) unveil substructures along the line-of-sight toward distant galaxies, and (iii) compare the shape and the slope of baryons and dark matter distributions i…
Is Titan's shape caused by its meteorology and carbon cycle?
Sotin, C.; Choukroun, M.
Titan's shape is characterized by a difference between the long equatorial radius and the polar radius that is several hundred meters larger than that predicted by the flattening due to its spin rate. The North polar region is covered by large mare filled with hydrocarbons, including ethane. Moreover global circulation models predict ethane precip…
Herschel-SPIRE Imaging Spectroscopy of Molecular Gas in M82
Cooray, A.; Isaak, K. G.; Lebouteiller, V. +14 more
We present new Herschel-SPIRE imaging spectroscopy (194-671 µm) of the bright starburst galaxy M82. Covering the CO ladder from J = 4 → 3 to J = 13 → 12, spectra were obtained at multiple positions for a fully sampled ~3 × 3 arcmin map, including a longer exposure at the central position. We present measurements of 12CO, 13
Planetary period oscillations in Saturn's magnetosphere: Evolution of magnetic oscillation properties from southern summer to post-equinox
Dougherty, M. K.; Lamy, L.; Andrews, D. J. +3 more
We investigate the evolution of the properties of planetary period magnetic field oscillations observed by the Cassini spacecraft in Saturn's magnetosphere over the interval from late 2004 to early 2011, spanning equinox in mid-2009. Oscillations within the inner quasi-dipolar region (L ≤ 12) consist of two components of close but distinct periods…
Solar Coronal Loops Resolved by Hinode and the Solar Dynamics Observatory
Warren, Harry P.; Ugarte-Urra, Ignacio; Brooks, David H.
Despite decades of studying the Sun, the coronal heating problem remains unsolved. One fundamental issue is that we do not know the spatial scale of the coronal heating mechanism. At a spatial resolution of 1000 km or more, it is likely that most observations represent superpositions of multiple unresolved structures. In this Letter, we use a comb…
The SL2S Galaxy-scale Gravitational Lens Sample. I. The Alignment of Mass and Light in Massive Early-type Galaxies at z = 0.2-0.9
Treu, Tommaso; Gavazzi, Raphaël; Marshall, Philip J. +2 more
We study the relative alignment of mass and light in a sample of 16 massive early-type galaxies at z = 0.2-0.9 that act as strong gravitational lenses. The sample was identified from deep multi-band images obtained as part of the Canada-France-Hawaii Telescope Legacy Survey and as part of the Strong Lensing Legacy Survey (SL2S). Higher resolution …
The Relation between Cool Cluster Cores and Herschel-detected Star Formation in Brightest Cluster Galaxies
Smith, G. P.; Altieri, B.; Valtchanov, I. +12 more
We present far-infrared (FIR) analysis of 68 brightest cluster galaxies (BCGs) at 0.08 < z < 1.0. Deriving total infrared luminosities directly from Spitzer and Herschel photometry spanning the peak of the dust component (24-500 µm), we calculate the obscured star formation rate (SFR). 22+6.2 -5.3% of the BCGs are…
Supergranules as Probes of the Sun's Meridional Circulation
Hathaway, David H.
Recent analysis revealed that supergranules (convection cells seen at the Sun's surface) are advected by the zonal flows at depths equal to the widths of the cells themselves. Here we probe the structure of the meridional circulation by cross-correlating maps of the Doppler velocity signal using a series of successively longer time lags between ma…