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The Tilted Solar Dipole as Observed and Modeled during the 1996 Solar Minimum
Raouafi, N. -E.; Petrie, G. J. D.; Norton, A. A.
We examine the tilt of the solar magnetic dipole away from the rotational axis near the 1996 solar minimum. A persistent tilted dipole may result from an MHD instability acting on the toroidal bands in the solar interior. Nonaxisymmetric eruption of sunspots has been predicted by dynamo theory and observed in sunspot location patterns. The decay o…
Near-infrared polarization images of the Orion proplyds
Eckart, A.; Ott, T.; Rost, S.
Aims: The aim is to study structure and polarization properties of the stars and planet systems in the active Orion H II-region.
Methods: We performed AO-assisted high-resolution imaging polarimetry on selected Orion proplyds close to the Trapezium stars in the J, H, and K bands. Differential polarimetric images of one of the largest and brigh…
Solar wind dependence of ion parameters in the Earth's magnetospheric region calculated from CLUSTER observations
Taylor, M. G. G. T.; Denton, M. H.
Moments calculated from the ion distributions (~0-40 keV) measured by the Cluster Ion Spectrometry (CIS) instrument are combined with data from the Cluster Flux Gate Magnetometer (FGM) instrument and used to characterise the bulk properties of the plasma in the near-Earth magnetosphere over five years (2001-2005). Results are presented in the form…
Fueling QSOs: the relevance of mergers
Canalizo, G.; Schweizer, F.; Lacy, M. +4 more
To study the relevance of mergers for the fueling of QSOs, we are currently conducting an HST imaging campaign of a sample of QSO host galaxies classified as ellipticals in the literature. Here, we present results from a study of the first five QSO host galaxies imaged with HST/ACS. For the majority of objects, strong signs of interactions such as…
Latitude Dependence of the Variations of Sunspot Group Numbers (SGN) and Coronal Mass Ejections (CMEs) in Cycle 23
Kane, R. P.
The 12-month running means of the conventional sunspot number Rz, the sunspot group numbers (SGN) and the frequency of occurrence of Coronal Mass Ejections (CMEs) were examined for cycle 23 (1996 - 2006). For the whole disc, the SGN and Rz plots were almost identical. Hence, SGN could be used as a proxy for Rz, for which latitude data are not avai…
Plasma transport along discrete auroral arcs and its contribution to the ionospheric plasma convection
Fazakerley, A. N.; Nilsson, H.; Buchert, S. +6 more
The role of intense high-altitude electric field (E-field) peaks for large-scale plasma convection is investigated with the help of Cluster E-field, B-field and density data. The study covers 32 E-field events between 4 and 7 RE geocentric distance, with E-field magnitudes in the range 500 1000 mV/m when mapped to ionospheric altitude. …
Low heat conduction in white dwarf boundary layers?
Burwitz, V.; Liu, F. K.; Meyer, F. +1 more
Context: X-ray spectra of dwarf novae in quiescence observed by Chandra and XMM-Newton provide new information on the boundary layers of their accreting white dwarfs.
Aims: Comparison of observations and models allows us to extract estimates for the thermal conductivity in the accretion layer and reach conclusions on the relevant physical proc…
A Cosmologically Motivated Description of the Dark Matter Halo Profile for the Low Surface Brightness Galaxy, Malin 1
Seigar, Marc S.
In this paper we derive a possible mass profile for the low surface brightness galaxy, Malin 1, based upon previously published space-based and ground-based photometric properties and kinematics. We use properties of the bulge, normal disk, outer extended disk, and H i mass as inputs into mass profile models. We find that the dark matter halo mode…
Bifurcation of the tail current sheet and ion temperature anisotropy
Israelevich, P. L.; Ershkovich, A. I.
We investigated the relation between the geotail current sheet structure and the anisotropy of the ion temperature in the plasma sheet. Current density distribution in the geomagnetic tail is shown not to depend on the ratio between the parallel and perpendicular ion temperature. The tail current sheet bifurcation is controlled by non-gyrotropicit…
SMART-1 highlights and relevant studies on early bombardment and geological processes on rocky planets
Grande, M.; Koschny, D.; Mall, U. +16 more
We present results from SMART-1 science and technology payload, in the context of the Nobel symposium on 'Physics of Planetary Systems'. SMART-1 is Europe' first lunar mission (Foing et al 2000 LPSC XXXI Abstract #1677 (CDROM); Foing et al 2001 Earth, Moon Planets 85 86 523 31 Marini et al 2002 Adv. Space Res. 30 1895 900 Racca et al 2001 Earth Mo…