An asymptotic formula for the pion decay constant in a large volume
نویسندگان
چکیده
We derive an asymptotic formula à la Lüscher for the finite volume correction to the pion decay constant: this is expressed as an integral over the 〈3π|Aμ|0〉 amplitude after proper subtraction of the pion pole contribution. We analyze the formula numerically at leading and nextto-leading order in the chiral expansion.
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