Physics
Scientific paper
Dec 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008agufmsh21b1614c&link_type=abstract
American Geophysical Union, Fall Meeting 2008, abstract #SH21B-1614
Physics
2114 Energetic Particles (7514), 2124 Heliopause And Solar Wind Termination, 2126 Heliosphere/Interstellar Medium Interactions
Scientific paper
In December 2008 the Voyager 1 (V1) spacecraft will be at ~108 AU and 34 deg N. It is in the heliosheath, ~17 AU beyond the solar wind termination shock (TS) at that latitude. The Voyager 2 (V2) spacecraft will be at ~88 AU and 28 deg S. It also is in the heliosheath, having crossed the TS several times from 30 August to 1 September 2007 at 83.7 AU. The energy spectra of H, He, and O in the heliosheath show evidence of three separate components: a low-energy termination shock particle (TSP) component that likely originates locally at the TS and is convected to the spacecraft, a high-energy galactic cosmic ray (GCR) component, and a mid-energy anomalous cosmic ray (ACR) component whose source region and acceleration mechanism are the subject of differing models. Since ~mid-2005 the TSP component at Voyager 1 has been remarkably steady. Subtracting this component and the GCR component reveals evolving ACR spectra that appear to be unfolding towards source spectra as V1 moves deeper into the heliosheath. At V2 there has been significant evolution in the TSP energy spectra during its ~one year in the heliosheath. Recently, however, the TSP energy spectra resemble those at V1 and the ACR energy spectra have a heavily modulated shape resulting in an energy-dependent positive gradient between the two spacecraft. We will examine the ACR energy spectra at both V1 and V2 and compare with predictions of competing theoretical models for the origin and acceleration of ACRs. This work was supported by NASA under contract NAS7-03001.
Cummings Alan C.
Heikkila Bryant C.
Lal Niranjan
McDonald Frank B.
Stone Edward C.
No associations
LandOfFree
Evolution of the Anomalous Cosmic Ray Energy Spectra at Voyager 1 and 2 in the Heliosheath 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 Evolution of the Anomalous Cosmic Ray Energy Spectra at Voyager 1 and 2 in the Heliosheath, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Evolution of the Anomalous Cosmic Ray Energy Spectra at Voyager 1 and 2 in the Heliosheath will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1246953