Acceleration of Interstellar Material at the Solar Wind Termination Shock

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

Somewhere beyond 70 AU, where the solar wind pressure is balanced by that of the local interstellar medium, is a shock beyond which the solar wind is no longer supersonic. There is now strong evidence that this solar wind termination shock is an efficient particle accelerator, capable of accelerating ions to beyond 1 GeV on a time scale of ~ 1 year. The observed ions are called "anomalous cosmic rays" (ACRs) because of their unusual composition, which includes H, He, C, N, O, Ne, and Ar. ACRs are mainly singly-charged, and originate from interstellar neutral particles that have been swept into the heliosphere, ionized by solar UV or charge exchange with the solar wind, and then picked up by the solar wind and convected to the termination shock where they are accelerated to energies of 1 to 50 MeV/nuc. Data from a number of spacecraft now verify most of the details of this picture. Ulysses has observed the incoming neutrals and freshly-ionized "pick-up" ions directly. SAMPEX has used the Earth's field as a magnetic spectrometer to show that the highest energy ACRs are multiply-charged, thereby providing important new tests of shock acceleration models. Voyager observations imply that the shock is presently located at about 85 AU, which Voyager-1 will reach within the decade. We review this new evidence and discuss the implications for shock acceleration models, for the nature and composition of the local interstellar medium, and for models of galactic cosmic ray origin and acceleration.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Acceleration of Interstellar Material at the Solar Wind Termination Shock does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Acceleration of Interstellar Material at the Solar Wind Termination Shock, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Acceleration of Interstellar Material at the Solar Wind Termination Shock will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-817378

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.