Search Publications
Data-driven Magnetohydrodynamic Model for Active Region Evolution
Liu, Yang; Wu, S. T.; Hoeksema, J. Todd +1 more
We present a self-consistent, three-dimensional, magnetohydrodynamics model together with time-dependent boundary conditions based on the projected method of characteristics at the source surface (photosphere) to accommodate the observations. The new physics included in this model are differential rotation, meridional flow, effective diffusion, an…
Titan's near magnetotail from magnetic field and electron plasma observations and modeling: Cassini flybys TA, TB, and T3
André, N.; Lewis, G. R.; Russell, C. T. +14 more
The first close Titan encounters TA, TB, and T3 of the Cassini mission at almost the same Saturnian local time ∼1030 and in the same spatial region downstream of Titan have enabled us to study the formation of the tail of its induced magnetosphere. The study is based on magnetic field and electron plasma observations as well as three-dimensional m…
RHESSI Observation of Chromospheric Evaporation
Liu, Wei; Liu, Siming; Jiang, Yan Wei +1 more
We present analyses of the spatial and spectral evolution of hard X-ray emission observed by RHESSI during the impulsive phase of an M1.7 flare on 2003 November 13. In general, as expected, the loop top (LT) source dominates at low energies, while the footpoint (FP) sources dominate the high-energy emission. At intermediate energies, both the LT a…
Global distribution of total ozone on Mars from SPICAM/MEX UV measurements
Montmessin, F.; Fedorova, A.; Korablev, O. +4 more
The dual UV/IR spectrometer SPICAM on board the European mission Mars Express is dedicated to monitoring the Martian atmosphere and has recorded spectra for more than one Martian year, from January 2004 to April 2006, over a large range of latitudes and longitudes. SPICAM UV spectra were recorded on the day side in a nadir geometry, in the 110-320…
Stellar occultations observed by SPICAM on Mars Express
Bertaux, Jean-Loup; Korablev, Oleg; Quémerais, Eric +4 more
Spectroscopy for the Investigation of the Characteristics of the Atmosphere of Mars (SPICAM) is the first instrument orbiting a planet other than Earth that is dedicated to the technique of stellar occultation. During the first year of operation on board Mars Express, SPICAM observed more than 500 star occultations, yielding vertical profiles of C…
Reflectance spectra and chemical structure of Titan's tholins: Application to the analysis of Cassini Huygens observations
Quirico, E.; Schmitt, B.; Coll, P. +7 more
Titan's tholins are used as analogs of Titan's aerosols and N-rich organic solids present on many icy surfaces. However, it is not clear whether or not they are relevant analogs, and which kind of tholins should be used among a wide set available in literature. This paper presents reflectance spectral data of two tholins selected as end-members of…
Observing the Modification of the Acoustic Cutoff Frequency by Field Inclination Angle
McIntosh, Scott W.; Jefferies, Stuart M.
We use observations of a sunspot from the Transition Region and Coronal Explorer (TRACE) spacecraft to demonstrate observationally the modification of the acoustic cutoff frequency in the lower solar chromosphere by the changing the inclination of the magnetic field as first predicted theoretically by Bel & Leroy.
Interferometric 890 µm Images of High-Redshift Submillimeter Galaxies
Le Floc'h, E.; Yun, M. S.; Scott, D. +12 more
We present high-resolution 890 µm images of two 20 mJy submillimeter galaxies, SMM J123711+622212 and MIPS J142824.0+352619, obtained using the Submillimeter Array (SMA). Using submillimeter interferometric observations with an angular resolution of 2.5", the coordinates of these high-redshift sources are determined with an accuracy of 0.2".…
The early phases of a solar prominence eruption and associated flare: a multi-wavelength analysis
Mason, H. E.; Isobe, H.; Tripathi, D. +2 more
Aims.We aim to examine the precursor phases and early evolution of a prominence eruption associated with a M4-class flare and a partial halo coronal mass ejection (CME) observed on 2005 July 27. Our main goal is to investigate the precursor eruption signatures observed in EUV, X-ray and microwave emission and their relation to the prominence desta…
Chemical evolution in Sérsic 159-03 observed with XMM-Newton
Kaastra, J. S.; de Plaa, J.; Vink, J. +6 more
Using a new long X-ray observation of the cluster of galaxies Sérsic 159-03 with XMM-Newton, we derive radial temperature and abundance profiles using single- and multi-temperature models. The fits to the EPIC and RGS spectra prefer multi-temperature models especially in the core. The radial profiles of oxygen and iron measured with EPIC/RGS and t…