mean mass range

in nuclear chemistry
https://doi.org/10.1351/goldbook.M03783
The mean linear range multiplied by the mass density of the material.
Source:
PAC, 1982, 54, 1533. 'Glossary of terms used in nuclear analytical chemistry (Provisional)' on page 1550 (https://doi.org/10.1351/pac198254081533)