What is a dry electron? I was reading about water photolysis which produces a positive water radical and a dry electron, or an excited water $\ce{H2O^*}$ through the following equation

$$\ce{
H2O -&gt;[$hv$] H2O^{.+} + e_{dry}^-, or~ H2O^*
}$$
(as seen in this link)

By opposition I have also seen $\ce{e_{aq}^-}$ (as seen in pp. 2 of this link).

I can understand the "positive water" and even the "excited water", but what is a "dry electron"? And what is an $\ce{e_{aq}^-}$ (wet electron? I am unsure of how to translate the term I had learned to english). Why not simply say "free electron"?
A "dry" electron is an electron released from the event of an ionization. Depend on source the electron can either be defined as:


  "The $e^-$ is a 'dry electron' that still retains some of the excess
  kinetic energy acquired from the ionizing event."$\ce{^{[1]}}$


or,


  "The 'dry-electron' (defined as an electron before solvation)
  ..."$\ce{^{[2]}}$


A dry electron is thus, an electron that is not assiciated with any atoms, molecules or solutions.

Reference

$\ce{[1]}$ Thormod Henriksen, David H. Maillie; Radiation and Health; page 157

$\ce{[2]}$ J.D. Simon; Ultrafast Dynamics of Chemical Systems; page 144