Publications [#281169] of Peter K. Haff

Papers Published

1. Haff, PK; Watson, CC; Yung, YL, Sputter ejection of matter from Io, J. Geophys. Res. (Usa), vol. 86 no. A8 (1981), pp. 6933-6938
   (last updated on 2023/06/01)

   Abstract:
   The direct collisional interaction of magnetospheric particles with Io will lead to sputtering of atoms and molecules from the satellite into circum-Jovian space. The ~520-eV S (and ~260-eV O) ions composing the Io torus are the most effective agents for net sputter removal of matter from the satellite. An incident flux of ~1010 cm-2 s-1 is estimated to provide ~5×1010 S atoms cm-2 s-1 from sputtering of a (dayside) atmosphere with an exobase at a few hundred kilometers and up to ~1012 S atoms cm-2 s-1 from an atmosphere at 1500K with an exobase at ~2.2 RIo. The supply of S (and O) required to stabilize the torus has been estimated. If Na and K are present in the atmosphere at a concentration level of 1%, the corresponding sputtering rates are calculated. Sputtering can also remove heavy molecules, like Sn, from the atmosphere. All atomic species residing on the surface must be ejected into circum-Jovian space at a rate approximately proportional to their (surface) abundances, if direct surface sputtering occurs, so that the particle content of the inner Jovian magnetosphere should map rather faithfully all species present on Io's surface

   Keywords:
   Jupiter;planetary atmospheres;planetary satellites;