Astronomy and Astrophysics – Astrophysics
Scientific paper
May 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006agusmsh51a..07h&link_type=abstract
American Geophysical Union, Fall Meeting 2007, abstract #SH51A-07
Astronomy and Astrophysics
Astrophysics
7594 Instruments And Techniques
Scientific paper
Neutral atom detection is a useful way of studying astrophysical plasma structures. When plasma ions undergo charge exchange with the neutral background gas, energetic neutral atoms (ENAs) are generated. These neutral atoms travel in straight lines from the point of charge exchange because they are not subject to deflection by the electric and magnetic fields in space and as a result ENAs can be used to image the plasma structures from which they originate. ENAs in the energy range from .01 to 1.5 keV are particularly worth studying and are best detected by their conversion to negative ions at a surface, a method that is being used in the IMAGE** spacecraft's low energy neutral atom (LENA) imager. While the results from LENA are contributing to knowledge of the Earth's magnetosphere, the low efficiency (<1%) limits temporal and spatial resolution. In order to improve the efficiency of conversion, we have begun detailed studies of the properties of a variety of surfaces and have correlated surface properties with conversion efficiencies. The surfaces studied so far are tungsten, highly oriented pyrolytic graphite (HOPG), diamond-like carbon and secondary electron emitting glasses. XPS spectra and work function for clean samples and samples exposed to the atmosphere have been taken. The results have been compared with measured conversion efficiencies. For the tungsten surfaces, it appears that adsorbates play an important role in conversion efficiency. This has implications for the sensitivity and stability of neutral atom imagers. *T.E. Moore, et. al., Space Sci. Rev. 91, 155 (2000). ** Work supported in part by NASA grant ACT-05-0040
Chornay Dennis
Collier Mark
Coplan Mike
Defazio J.
Hughes Patrick P.
No associations
LandOfFree
Efficient Surface Conversion for Neutral Atom Detection* 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 Efficient Surface Conversion for Neutral Atom Detection*, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Efficient Surface Conversion for Neutral Atom Detection* will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1026994