Observation of High Iron Charge States over <0.1 to ~1 MeV/nucleon in Solar Energetic Particle Events

Details Observation of High Iron Charge States over <0.1 to ~1 MeV/nucleon in Solar Energetic Particle Events Observation of High Iron Charge States over <0.1 to ~1 MeV/nucleon in Solar Energetic Particle Events

Dec 2010

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010agufmsh42b..07g&link_type=abstract

American Geophysical Union, Fall Meeting 2010, abstract #SH42B-07

Astronomy and Astrophysics

Astrophysics

[7514] Solar Physics, Astrophysics, And Astronomy / Energetic Particles

Scientific paper

The ionic charge states of Solar Energetic Particle (SEP) events provide direct information about the physical properties of the source plasma and related acceleration processes. In gradual events iron consistently shows ~10-11 reflecting typical corona temperatures, while impulsive events yield a sharp increase in QFe with energy, indicating energy dependent stripping. Both types of events approach similar values for for E<0.1 MeV/nuc, indicating similar source temperature of 1-3 MK. However, distributions with QFe>16 have frequently been found in the solar wind, particularly coming from active regions. This observation suggests the presence of highly charged iron ions in potential SEP source populations, while so far such high QFe has not been observed at low SEP energies. Therefore, we performed a survey of iron charge states in all SEP events observed with ACE SEPICA during 1998 - 2000, complemented by ACE SWICS and SOHO STOF. Out of 89 events we found a set of 6 with >14 over the entire SEPICA energy range of 0.08-0.54 MeV/nuc. The presence of high charge states over the entire energy range would require either extremely strong adiabatic deceleration with a very short mean free path during interplanetary transport or high temperature source material. All 6 events show enhanced abundances in heavy ions and 3He, but only one of these events exhibits the strong increase in charge state with energy typically observed in impulsive events. The high temperature source material may be well correlated to the hot active regions during flare events. However, a consistent association with specific solar events and a related acceleration mechanism for these SEPs has yet to be found.

Affiliated with

Also associated with

No associations

Rating

Observation of High Iron Charge States over <0.1 to ~1 MeV/nucleon in Solar Energetic Particle Events 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 Observation of High Iron Charge States over <0.1 to ~1 MeV/nucleon in Solar Energetic Particle Events, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observation of High Iron Charge States over <0.1 to ~1 MeV/nucleon in Solar Energetic Particle Events will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1510570