Search Publications
New Insight into Short-wavelength Solar Wind Fluctuations from Vlasov Theory
Belmont, G.; Sahraoui, F.; Goldstein, M. L.
The nature of solar wind (SW) turbulence below the proton gyroscale is a topic that is being investigated extensively nowadays, both theoretically and observationally. Although recent observations gave evidence of the dominance of kinetic Alfvén waves (KAWs) at sub-ion scales with ω < ωci, other studies suggest that the KAW mode cann…
Calibrating 100 Years of Polar Faculae Measurements: Implications for the Evolution of the Heliospheric Magnetic Field
DeLuca, Edward E.; Zhang, Jie; Muñoz-Jaramillo, Andrés +1 more
Although the Sun's polar magnetic fields are thought to provide important clues for understanding the 11 year sunspot cycle, including the observed variations of its amplitude and period, the current database of high-quality polar field measurements spans relatively few sunspot cycles. In this paper, we address this deficiency by consolidating Mou…
An analysis of open-basin lake deposits on Mars: Evidence for the nature of associated lacustrine deposits and post-lacustrine modification processes
Mustard, John F.; Goudge, Timothy A.; Head, James W. +1 more
A large number of candidate open-basin lakes (low-lying regions with both inlet valleys and an outlet valley) have been identified and mapped on Mars and are fed by valley network systems that were active near the Noachian-Hesperian boundary. The nature of processes that modified the open-basin lake interiors subsequent to lacustrine activity, and…
XMM-Newton Detects a Hot Gaseous Halo in the Fastest Rotating Spiral Galaxy UGC 12591
Bregman, Joel N.; Anderson, Michael E.; Miller, Jon M. +1 more
We present our XMM-Newton observation of the fastest rotating spiral galaxy UGC 12591. We detect hot gas halo emission out to 80 kpc from the galaxy center, and constrain the halo gas mass to be smaller than 4.5 × 1011 M ⊙. We also measure the temperature of the hot gas as T = 0.64 ± 0.03 keV. Combining our x-ray constraints …
Kepler observations of flaring in A-F type stars
Balona, L. A.
Optical flares on early F- and A-type stars have never been observed with certainty. Inspection of several thousands of these stars in the Kepler public archives resulted in the discovery of flares in 25 G-type and 27 F-type stars. Because A-type stars are thought not to be active, the detection of flares on 19 A-type stars from a sample of nearly…
The Star Formation in Radio Survey: GBT 33 GHz Observations of Nearby Galaxy Nuclei and Extranuclear Star-forming Regions
Helou, G.; Murphy, E. J.; Armus, L. +7 more
We present 33 GHz photometry of 103 galaxy nuclei and extranuclear star-forming complexes taken with the Green Bank Telescope as part of the Star Formation in Radio Survey. Among the sources without evidence for an active galactic nucleus, and also having lower frequency radio data, we find a median thermal fraction at 33 GHz of ≈76% with a disper…
The Evolution of Lyα-emitting Galaxies between z = 2.1 and z = 3.1
Gronwall, Caryl; Gawiser, Eric; Ciardullo, Robin +11 more
We describe the results of a new, wide-field survey for z = 3.1 Lyα emitters (LAEs) in the Extended Chandra Deep Field South (ECDF-S). By using a nearly top-hat 5010 Å filter and complementary broadband photometry from the MUSYC survey, we identify a complete sample of 141 objects with monochromatic fluxes brighter than 2.4 × 10-17 erg …
An icy Kuiper belt around the young solar-type star HD 181327
Pinte, C.; Ménard, F.; Duchêne, G. +18 more
Context. HD 181327 is a young main sequence F5/F6 V star belonging to the
Aims: We aim to study the dust properties in the belt in d…
Supermagnetosonic subsolar magnetosheath jets and their effects: from the solar wind to the ionospheric convection
Dandouras, I.; Vaivads, A.; Lucek, E. A. +7 more
It has recently been proposed that ripples inherent to the bow shock during radial interplanetary magnetic field (IMF) may produce local high speed flows in the magnetosheath. These jets can have a dynamic pressure much larger than the dynamic pressure of the solar wind. On 17 March 2007, several jets of this type were observed by the Cluster spac…
Morphology of the cloud tops as observed by the Venus Express Monitoring Camera
Crisp, David; Almeida, Miguel; Esposito, Larry W. +14 more
Since the discovery of ultraviolet markings on Venus, their observations have been a powerful tool to study the morphology, motions and dynamical state at the cloud top level. Here we present the results of investigation of the cloud top morphology performed by the Venus Monitoring Camera (VMC) during more than 3 years of the Venus Express mission…