Equation 19 · Part 1 · The Valley of Stability Is a Fitness Landscape
Symbol A
What this part means
the fix the mass number.
Its job in the formula
A is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol A→Article meaning
Where the article explains it
Fix the mass number A and let Z vary.
The passage around this formula
Fix the mass number A and let Z vary. Because the Coulomb and asymmetry terms in the semi-empirical mass formula are both approximately quadratic in Z at fixed A , the atomic mass along an isobaric chain is, to good approximation, a parabola in Z :
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
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Sources cited in the article section
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