Search Publications
Spatially resolved HST/STIS observations of Io's dayside equatorial atmosphere
Spencer, John R.; Jessup, Kandis Lea
We report on an investigation of the spatial distribution of Io's atmosphere, and its diurnal variability, using Hubble's Space Telescope Imaging Spectrograph (HST/STIS). From December 2010 to January 2012, we obtained spatially resolved limb-to-limb 2100-3100 Å spectra at low latitudes (<30°), with the STIS 0.1″ slit. Spectra taken at two cent…
Physical Conditions in the X-Ray Emission-line Gas in NGC 1068
Turner, T. J.; Kraemer, S. B.; Crenshaw, D. Michael +2 more
We present a detailed, photoionization modeling analysis of XMM-Newton/Reflection Grating Spectrometer observations of the Seyfert 2 galaxy NGC 1068. The spectrum, previously analyzed by Kinkhabwala et al., reveals a myriad of soft X-ray emission lines, including those from H- and He-like carbon, nitrogen, oxygen, and neon, and M- and L-shell iron…
Alfvénic waves in polar spicules
Koutchmy, S.; Ahangarzadeh Maralani, A. R.; Tavabi, E. +2 more
Context. For investigating spicules from the photosphere to coronal heights, the new Hinode/SOT long series of high-resolution observations from space taken in CaII H line emission offers an improved way to look at their remarkable dynamical behavior using images free of seeing effects. They should be put in the context of the huge amount of alrea…
Temperature and Electron Density Diagnostics of a Candle-flame-shaped Flare
Longcope, D. W.; McKenzie, D. E.; Plowman, J. E. +2 more
Candle-flame-shaped flares are archetypical structures that provide indirect evidence of magnetic reconnection. A flare resembling Tsuneta's famous 1992 candle-flame flare occurred on 2011 January 28; we present its temperature and electron density diagnostics. This flare was observed with Solar Dynamics Observatory/Atmospheric Imaging Assembly (S…
Infrared study of transitional disks in Ophiuchus with Herschel
André, Philippe; Ábrahám, Péter; Bouy, Hervé +7 more
Context. Observations of nearby star-forming regions with the Herschel Space Observatory complement our view of the protoplanetary disks in Ophiuchus with information about the outer disks.
Aims: The main goal of this project is to provide new far-infrared fluxes for the known disks in the core region of Ophiuchus and to identify potential tr…
Energy dependence of the band-limited noise in black hole X-ray binaries★
Stiele, H.; Yu, W.
Black hole low-mass X-ray binaries show a variety of variability features, which manifest as narrow peak-like structures superposed on broad noise components in power density spectra in the hard X-ray emission. In this work, we study variability properties of the band-limited noise component during the low-hard state for a sample of black hole X-r…
Cassini ISS astrometry of the Saturnian satellites: Tethys, Dione, Rhea, Iapetus, and Phoebe 2004-2012
Cooper, N. J.; Lainey, V.; Murray, C. D. +1 more
Context. The Cassini spacecraft has been orbiting Saturn since 2004 and has returned images of satellites with an astrometric resolution as high as a few hundred meters per pixel.
Aims: We used the images taken by the Narrow Angle Camera (NAC) of the Image Science Subsystem (ISS) instrument on board Cassini, for the purpose of astrometry.
The dayside reconnection voltage applied to Saturn's magnetosphere
Masters, A.
The ability of magnetic reconnection between interplanetary and planetary magnetic fields to drive a planetary magnetosphere can be quantified as the resulting voltage applied to the system. We present analytical model predictions of the dayside reconnection voltage at Saturn, a planet where solar wind driving has been the subject of debate. Model…
Estimating precipitation on early Mars using a radiative-convective model of the atmosphere and comparison with inferred runoff from geomorphology
Rauer, H.; Jaumann, R.; Tirsch, D. +5 more
We compare estimates of atmospheric precipitation during the Martian Noachian-Hesperian boundary 3.8 Gyr ago as calculated in a radiative-convective column model of the atmosphere with runoff values estimated from a geomorphological analysis of dendritic valley network discharge rates. In the atmospheric model, we assume CO2-H2
Origins of massive field stars in the Galactic Centre: a spectroscopic study
Morris, Mark R.; Wang, Q. Daniel; Dong, Hui +2 more
Outside of the known star clusters in the Galactic Centre, a large number of evolved massive stars have been detected; but their origins remain uncertain. We present a spectroscopic study of eight such stars, based on new Gemini Near-Infrared Spectrograph (GNIRS) and Near-IR Integral Field Spectrograph (NIFS) near-infrared observations. This work …