Consequence of Electron Mobility in Icy Grains on Solar System Objects

Details Consequence of Electron Mobility in Icy Grains on Solar System Objects Consequence of Electron Mobility in Icy Grains on Solar System Objects

Dec 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007dps....39.3809g&link_type=abstract

American Astronomical Society, DPS meeting #39, #38.09; Bulletin of the American Astronomical Society, Vol. 39, p.490

Astronomy and Astrophysics

Astronomy

Scientific paper

Solar system ices have been shown to contain organic molecules, whether in the ice on Mars, comets such as Tempel-1 or on the surfaces of Europa, Ganymede, and Callisto. Sub-surface oceans containing ionic salts have been proposed to interpret the induced components of the local magnetic fields at these Galilean moons. Recent laboratory studies have shown that radiation processing of water-rich ices containing aromatic organic impurities readily ionizes organic molecules imbedded in an ice matrix. As a result, transient charge separation is produced more efficiently in ices containing organic impurities. This charge separation is partially stabilized by electron trapping. This could have important consequences since the icy moons of the giant planets are imbedded in both the magnetic field and trapped particle radiation environments of the planetary magnetospheres. Here we present new experimental results and theoretical modelling that deals with mobility of electrons produced by photoionization of PAHs (polycyclic aromatic hydrocarbons) in an ice matrix. We find that a small portion of the electrons (about 5% of the originally generated) are weakly trapped in the impurity-containing ices and can be made mobile at temperatures between 50 K and 125 K. Current flow of these mobile electrons could affect electrical conductivity of the irradiated surfaces and contribute to induced magnetic fields. This solid-state micro-ionospheric environment, comparable to a thin metallic conducting shell, may then need to be taken into account, along with the above-surface ionosphere, in modelling background variations affecting detection of induced magnetic fields from the sub-surface oceans.
References:
1. M. S. Gudipati, L. J. Allamandola, J. F. Cooper, S. Sturner, R. E. Johnson (in preparation)
2. J. F. Cooper, R. E. Johnson, B. H. Mauk, H. B. Garrett, N. Gehrels, Icarus 149, 133 (2001).
3. M. S. Gudipati, L. J. Allamandola, Journal of Physical Chemistry A 110, 9020 (2006).

Affiliated with

Also associated with

No associations

Rating

Consequence of Electron Mobility in Icy Grains on Solar System Objects 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 Consequence of Electron Mobility in Icy Grains on Solar System Objects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Consequence of Electron Mobility in Icy Grains on Solar System Objects will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1111030