Search Publications
MeV Dark Matter: Has It Been Detected?
Silk, Joseph; Hooper, Dan; Paul, Jacques +2 more
We discuss the possibility that the recent detection of 511keV γ rays from the galactic bulge, as observed by INTEGRAL, is a consequence of low mass (1 100 MeV) particle dark matter annihilations. We discuss the type of halo profile favored by the observations as well as the size of the annihilation cross section needed to account for the signal. …
Structure of the Magnetic Reconnection Diffusion Region from Four-Spacecraft Observations
André, M.; Khotyaintsev, Y.; Vaivads, A. +6 more
Magnetic reconnection leads to energy conversion in large volumes in space but is initiated in small diffusion regions. Because of the small sizes of the diffusion regions, their crossings by spacecraft are rare. We report four-spacecraft observations of a diffusion region encounter at the Earth's magnetopause that allow us to reliably distinguish…
Surprising Sun: A New Step Towards a Complete Picture?
García, R. A.; Turck-Chièze, S.; Piau, L. +5 more
Important revisions of the solar model ingredients have appeared recently. We first show that the updated CNO composition suppresses the anomalous position of the Sun in the known galactic enrichment. The following law, He/H=0.075+44.6 O/H in number fraction, is now compatible with all the indicators. We then suggest some directions of investigati…
Theory and Observations of Slow-Mode Solitons in Space Plasmas
Stasiewicz, K.
A generalized model for one-dimensional magnetosonic structures of large amplitude in space plasmas is presented. The model is verified with multipoint measurements on Cluster satellites in the magnetosheath and the boundary layer under conditions of plasma beta (plasma/magnetic pressure) between 0.1 10. We demonstrate good agreement between the m…