Search Publications
Damping of Slow MHD Coronal Loop Oscillations by Shocks
Verwichte, E.; Haynes, M.; Arber, T. D. +1 more
The damping of slow magnetoacoustic coronal loop oscillations by shock dissipation is investigated. Observations of large-amplitude slow-mode observations made by SUMER show a clear dependency of the damping rate on the oscillation amplitude. Fully nonlinear MHD simulations of slow-mode oscillations in the presence of thermal conduction are perfor…
GALEX Spectroscopy of SN 2005ay Suggests Ultraviolet Spectral Uniformity among Type II-P Supernovae
Smith, G. P.; Gal-Yam, A.; Kirshner, R. P. +24 more
We present the initial results from our GALEX program designed to obtain ultraviolet (UV) spectra of nearby core-collapse supernovae (SNe). Our first target, SN 2005ay in the nearby galaxy NGC 3938, is a typical member of the SN II-P subclass. Our spectra show remarkable similarity to those of the prototypical Type II-P SN 1999em, and resemble als…
Analysis of Interplanetary Coronal Mass Ejection Parameters as a Function of Energetics, Source Location, and Magnetic Structure
Reinard, A. A.
We describe a study of how ICME parameters vary as function of source location, associated flare magnitude, and magnetic structure. The strongest compositional enhancements are found to occur in events originating in central longitudes of the Sun, those with large associated flares, and those that are identified as magnetic clouds. In situ velocit…
On contamination and completeness in z >= 5 Lyman-break galaxy surveys
Lehnert, Matthew D.; Stanway, Elizabeth R.; Bremer, Malcolm N.
A large population of z > 5 Lyman-break galaxies has been identified in recent years. However, the high-redshift galaxies selected by different surveys are subject to a variety of selection effects - some overt, others more subtle. We present an analysis of sample completeness and contamination issues in high-redshift surveys, focusing on surve…
Optical identifications of five INTEGRAL hard X-ray sources in the Galactic plane
Bikmaev, I. F.; Sunyaev, R. A.; Sakhibullin, N. A. +4 more
The results of optical identifications of five hard X-ray sources in the Galactic plane from the INTEGRAL all-sky survey are presented. The X-ray data on one source (IGR J20216+4359) are published for the first time. The optical observations were performed with the 1.5-m RTT-150 telescope (Turkish National Observatory, Antalya, Turkey) and the 6-m…
Mechanics of Seismic Emission from Solar Flares
Lindsey, C.; Donea, A. -C.
Instances of seismic transients emitted into the solar interior in the impulsive phases of some solar flares offer a promising diagnostic tool, both for understanding the physics of solar flares and for the general development of local helioseismology. Among the prospective contributors to flare acoustic emission that have been considered are: i) …
Millisecond Microwave Spikes: Statistical Study and Application for Plasma Diagnostics
Rozhansky, I. V.; Fleishman, G. D.; Huang, G. -L.
We analyze a dense cluster of solar radio spikes registered at 4.5-6 GHz by the Purple Mountain Observatory spectrometer (Nanjing, China), operating in the 4.5-7.5 GHz range with 5 ms temporal resolution. To handle the data from the spectrometer, we developed a new technique that uses a nonlinear multi-Gaussian spectral fit based on χ2 …
The Effect of Magnetic Reconnection and Writhing in a Partial Filament Eruption
Liu, Rui; Alexander, David; Gilbert, Holly R. +1 more
We present observations from 2007 March 2 of a partial filament eruption characterized by two distinct phases of writhing motions: a quasi-static, slowly evolving phase followed by a rapid kinking phase showing a bifurcation of the filament. The quasi-static kinking motions are observed before there is any heating or flaring evident in EUV or soft…
Results from the ESA SREM monitors and comparison with existing radiation belt models
Nieminen, P.; Hajdas, W.; Bühler, P. +3 more
The Standard Radiation Environment Monitor (SREM) is a simple particle detector developed for wide application on ESA satellites. It measures high-energy protons and electrons of the space environment with a 20° angular resolution and limited spectral information. Of the ten SREMs that have been manufactured, four have so far flown. The first mode…
The early-type galaxies NGC 1407 and NGC 1400 - I. Spatially resolved radial kinematics and surface photometry
Forbes, Duncan A.; Proctor, Robert N.; Brough, Sarah +2 more
This is the first paper of a series focused on investigating the star formation and evolutionary history of the two early-type galaxies NGC 1407 and NGC 1400. They are the two brightest galaxies of the NGC 1407 (or Eridanus-A) group, one of the 60 groups studied as part of the Group Evolution Multi-wavelength Study.
Here, we present new high …