packing fraction

noun

1. Physics. a measure of the stability of an atomic nucleus, equal to 10 4 multiplied by the mass defect and divided by the mass number.

packing fraction

noun

1. a measure of the stability of a nucleus, equal to the difference between its mass in amu and its mass number, divided by the mass number

packing fraction

/ păk′ĭng /

1. The ratio of the total volume of a set of objects packed into a space to the volume of that space.
2. The difference between the isotopic mass of a nuclide and its mass number, divided by its mass number. The packing fraction is often interpreted as a measure of the stability of the nucleus.

Word History and Origins

Origin of packing fraction¹

First recorded in 1925–30

Example Sentences

For one, there’s the idea of packing fraction: If you pack balls into a volume, they can’t fill all the space.

From Slate

This small fraction, called the packing fraction, becomes energy.

From Time Magazine Archive