Search Publications
Solar wind dynamic pressure and electric field as the main factors controlling Saturn's aurorae
Coates, A. J.; Dougherty, M. K.; Kurth, W. S. +11 more
The interaction of the solar wind with Earth's magnetosphere gives rise to the bright polar aurorae and to geomagnetic storms, but the relation between the solar wind and the dynamics of the outer planets' magnetospheres is poorly understood. Jupiter's magnetospheric dynamics and aurorae are dominated by processes internal to the jovian system, wh…
Seismic Emission from the Solar Flares of 2003 October 28 and 29
Lindsey, C.; Donea, A. -C.
We report the detection of seismic waves emitted from powerful solar flares that occurred in NOAA Active Region 10486 on 2003 October 28 and 29. We used helioseismic holography to image the seismic sources of the waves. This technique was previously used to image the source of seismic emission from the large solar flare of 1996 July 9. Egression p…
The Double Star magnetic field investigation: instrument design, performance and highlights of the first year's observations
Balogh, A.; Zhang, T. L.; Glassmeier, K. -H. +19 more
One of the primary objectives of the Double Star mission is the accurate measurement of the magnetic field vector along the orbits of the two spacecraft. The magnetic field is an essential parameter for the understanding of space plasma processes and is also required for the effective interpretation of data from the other instruments on the spacec…
Cluster encounter of a magnetic reconnection diffusion region in the near-Earth magnetotail on September 19, 2003
Balogh, A.; Rème, H.; Mouikis, C. +7 more
We report a clear encounter by the Cluster spacecraft of a magnetic reconnection diffusion region in the near-Earth magnetotail at XGSM = -17.5 RE on September 19, 2003. In addition to the reversals of the plasma jets and of GSM-z (~normal) component of the magnetic field, clear signatures of Hall quadrupolar (GSM-y) magnetic…
In situ multi-satellite detection of coherent vortices as a manifestation of Alfvénic turbulence
Sundkvist, David; Vaivads, Andris; Krasnoselskikh, Vladimir +4 more
Turbulence in fluids and plasmas is a ubiquitous phenomenon driven by a variety of sources-currents, sheared flows, gradients in density and temperature, and so on. Turbulence involves fluctuations of physical properties on many different scales, which interact nonlinearly to produce self-organized structures in the form of vortices. Vortex motion…
Helioseismic Determination of the Solar Rotation Axis
Giles, P.; Beck, J. G.
Time-distance helioseismology analysis of Dopplergrams from the Michelson Doppler Imager instrument on board the Solar and Heliospheric Observatory spacecraft provides a very accurate measurement of meridional flows. This shows a sinusoidal variation with a period of 1 yr and was identified by P. Giles to be due to an error in the determination of…
Unstable relics as a source of galactic positrons
Pospelov, Maxim; Picciotto, Charles
We calculate the fluxes of 511 keV photons from the galactic bulge caused by positrons produced in the decays of relic particles with masses less than 100 MeV. In particular, we tighten the constraints on sterile neutrinos over a large domain of the mass-mixing angle parameter space, where the resulting photon flux would significantly exceed the e…
The Evolution of Reconnection along an Arcade of Magnetic Loops
Benz, Arnold O.; Grigis, Paolo C.
RHESSI observations of a solar flare showing continuous motions of double hard X-ray sources interpreted as footpoints of magnetic loops are presented. The temporal evolution shows many distinct emission peaks of duration of some tens of seconds (``elementary flare bursts''). Elementary flare bursts have been interpreted as instabilities or oscill…
The evolution of the galaxy B-band rest-frame morphology to z~ 2: new clues from the K20/GOODS sample
Cimatti, A.; Daddi, E.; Rodighiero, G. +7 more
We present a detailed analysis of the evolution of the rest-frame B-band morphology of K-selected galaxies with 0 < z < 2.5. This work is based on the K20 spectroscopic sample (Ks < 20) located within the Chandra Deep Field South area, coupled with the public deep GOODS (Great Observatories Origins Deep Surveys) Hubble Space Telescope (HS…
INTEGRAL and RXTE observations of accreting millisecond pulsar IGR J00291+5934 in outburst
Goldoni, P.; Stella, L.; Kuiper, L. +7 more
Simultaneous observations of the accretion-powered millisecond pulsar IGR J00291+5934 by the International Gamma-Ray Astrophysics Laboratory and Rossi X-ray Timing Explorer during the 2004 December outburst are analysed. The average spectrum is well described by thermal Comptonization with an electron temperature of 50 keV and Thomson optical dept…