Search Publications
Hydraulic modeling of a distributary channel of Athabasca Valles, Mars, using a high-resolution digital terrain model
Muller, Jan-Peter; Warner, Nicholas H.; Gupta, Sanjeev +2 more
Estimating magnitudes of flow rates in outflow channels has a central role in developing understanding of the paleohydrology of Mars. The typical approach to flow estimation is to identify geomorphic features, which indicate bankfull levels, and then use a hydraulic model to convert these levels into flow rates. Data constraints have meant that im…
In situ mass spectrometry during the Lutetia flyby
Wurz, P.; Altwegg, K.; Balsiger, H. +12 more
During the Rosetta flyby at asteroid Lutetia the ROSINA instrument tried to detect a thin exosphere of the asteroid. Although the instrument is sensitive enough to detect even very tenuous gases at a density level of 1 cm-3 the Lutetia exosphere could not be unambiguously detected due to spacecraft outgassing, which was not constant bec…
Dynamic modeling of cusp ion structures
Raeder, J.; Trattner, K. J.; Connor, H. J.
Dispersed ion structures observed near the magnetosphere cusps have long been used to infer locations and properties of reconnection at the Earth's magnetopause. However, observations are often difficult to interpret since spacecraft move relative to a cusp ion structure, creating temporal and spatial ambiguity in the observations. Models of cusp …
Detection of New Point Sources in WMAP 7 Year Data Using Internal Templates and Needlets
Scodeller, Sandro; Hansen, Frode K.; Marinucci, Domenico
We have developed a new needlet-based method to detect point sources in cosmic microwave background (CMB) maps and have applied it to the Wilkinson Microwave Anisotropy Probe (WMAP) 7 year data. We use both the individual frequency channels as well as internal templates, the latter being the difference between pairs of frequency channels and hence…
Spectral and spatial observations of microwave spikes and zebra structure in the short radio burst of May 29, 2003
Yan, Y.; Meshalkina, N. S.; Tan, C. +2 more
Context. The unusual radio burst of May 29, 2003 connected with the M1.5 flare in AR 10368 has been analyzed. It was observed by the Solar Broadband Radio Spectrometer (SBRS/Huairou station, Beijing) in the 5.2-7.6 GHz range. It proved to be only the third case of a neat zebra structure appearing among all observations at such high frequencies. De…
Waves as the Source of Apparent Twisting Motions in Sunspot Penumbrae
Solanki, S. K.; Bharti, L.; Hirzberger, J. +2 more
The motion of dark striations across bright filaments in a sunspot penumbra has become an important new diagnostic of convective gas flows in penumbral filaments. The nature of these striations has, however, remained unclear. Here, we present an analysis of small-scale motions in penumbral filaments in both simulations and observations. The simula…
The vertical distribution of the Venus NO nightglow: Limb profiles inversion and one-dimensional modeling
Bertaux, J. -L.; Gérard, J. -C.; Soret, L. +2 more
Ultraviolet (UV) spectra of the δ (190-240 nm) and γ (225-270 nm) bands of the nitric oxide (NO) molecule have been measured on the nightside of the atmosphere of Venus with the Spectroscopy for Investigation of Characteristics of the Atmosphere of Venus (SPICAV) instrument on board Venus Express (VEX). Excited NO molecules on the nightside of the…
Hot gas in groups: NGC 5328 and the intriguing case of NGC 4756 with XMM-Newton
Wolter, A.; Marino, A.; Trinchieri, G. +2 more
Context. Environment appears to have a strong influence on the fundamental properties of galaxies, modifying both their morphologies and their star formation histories. Similarly, galaxies play a role in determining the properties of the hot intergalactic medium in groups, heating and enriching it through a variety of mechanisms. NGC 5238 and NGC …
Observations of Outflowing Ultraviolet Absorbers in NGC 4051 with the Cosmic Origins Spectrograph
Turner, T. J.; Kraemer, S. B.; Crenshaw, D. M. +6 more
We present new Hubble Space Telescope (HST)/Cosmic Origins Spectrograph (COS) observations of the narrow-line Seyfert 1 galaxy NGC 4051. These data were obtained as part of a coordinated observing program including X-ray observations with the Chandra/High Energy Transmission Grating (HETG) spectrometer and Suzaku. We detected nine kinematic compon…
Magnetic Topology of a Naked Sunspot: Is It Really Naked?
Sainz Dalda, A.; Tarbell, T. D.; Vargas Domínguez, S.
The high spatial, temporal, and spectral resolution achieved by Hinode instruments gives much better understanding of the behavior of some elusive solar features, such as pores and naked sunspots. Their fast evolution and, in some cases, their small sizes have made their study difficult. The moving magnetic features (MMFs) have been studied during…