1. Charge exchange in cometary coma: Discovery of H− ions in the solar wind close to comet 67P/Churyumov‐Gerasimenko
- Author
-
Burch, J. L., Cravens, T. E., Llera, K., Goldstein, R., Mokashi, P., Tzou, C.‐Y., and Broiles, T.
- Subjects
comet ,solar wind ,530 Physics ,Astrophysics::High Energy Astrophysical Phenomena ,Physics::Space Physics ,Research Letter ,Magnetospheric Physics ,Astrophysics::Earth and Planetary Astrophysics ,Solar Wind Interactions with Unmagnetized Bodies ,charge exchange ,Space Sciences ,Research Letters - Abstract
As Rosetta was orbiting comet 67P/Churyumov‐Gerasimenko, the Ion and Electron Sensor detected negative particles with angular distributions like those of the concurrently measured solar wind protons but with fluxes of only about 10% of the proton fluxes and energies of about 90% of the proton energies. Using well‐known cross sections and energy‐loss data, it is determined that the fluxes and energies of the negative particles are consistent with the production of H− ions in the solar wind by double charge exchange with molecules in the coma., Key Points Double charge exchange of protons produces negative H ions in the solar windThe measurements agree with published laboratory cross sections and energy deficitsThe cross sections and energy deficits are estimated for the first time in the space environment
- Published
- 2015
- Full Text
- View/download PDF