HR: 17:05h
AN: SH54B-04    [Abstracts]
TI: Searching For Charge Interchange Cross-Sections Of Energetic Ions In Finite Temperature Matter
AU: * Perez-Peraza, J A
EM: perperaz@yahoo.com.mx
AF: Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Coyoacan, Mexico, DF 045510, Mexico
AU: Balderas-Aviles, G
EM: gabriel_balderas@hotmail.com
AF: Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Coyoacan, Mexico, DF 045510, Mexico
AB: - On basis to our knowledge in atomic physics of charge interchange cross sections of high energy ions (electron capture and electron loss) it is pretended to create cross sections for energetic ions in finite temperature matter – Temperature, T, is introduced by means of a relative velocity between ion projectiles and thermal targets – It is established criteria for charge interchange when ions are undergoing an acceleration process: these allow to determine whether ions undergo both electron loss and capture , or only one of the process, or even no one of them - on this basis, it is created an analytical expression describing the evolution of ion charge (namely effective charge qeff) when ions are being accelerated from local thermal energies up to energies where qeff reaches the atomic number Z – the expression for qeff is calibrated by fitting data of energy dependence of charge state of solar energetic ions, obtaining a quite reasonable fit; consequently, a 1st inference is that the created cross sections are not so distant from those prevailing in solar atmospheric matter – a 2nd calibration is carried out with the well known semi-empirical expression in laboratory experiments, by introducing collisional deceleration in the theoretical qeff expression instead of an acceleration process, so that beginning a high energies where the charge is Z there is a trend toward qeff ---> 0 as particles are being decelerated, in such a way that by taking T = 0 in our theoretical formalism it is expected to approach to the semi- empirical curve – the degree of deviation of such a fitting process gives an indication of how much the created cross sections are over/under estimated, such that by correcting them to reproduce the semi-empirical expression, we should obtain a calibration factor that when introduced in out T-dependent theoretical expression, should allows us to obtain still a better fitting of charge evolution of solar ions.
DE: 7514 Energetic particles (2114)
DE: 7519 Flares
DE: 7599 General or miscellaneous
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Fall Meeting