All Tables

Table 1: Energy threshold of reactions induced by positrons.
Table 2: Fraction (in %) of positrons forming positronium in flight, in a completely neutral medium.
Table 3: Reaction rates (in cm³/s) for the various processes after thermalization in the different ISM phases.
Table 4: Line widths (in keV) for various positron annihilation processes.
Table 5: Values of FWHMs obtained (in keV) in each ISM phase separately and in the "global'' case; the values are given for the "standard grain model'' ( $x_{\rm gr} = 1$ ), for $x_{\rm gr} = 0$ (no dust) and for $x_{\rm gr} = 10$ (overabundant and/or grain characteristics especially favorable for positron capture - see text), respectively. For the "global (combined)'' spectrum we give FWHM values in two cases: the McKee & Ostriker model with its phase densities and filling fractions, and the situation (results in parentheses) when the positrons are excluded from the cold phases.