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PCAC in Nuclear Medium and the Lovelace-Shapiro-Veneziano formula

J. Pasupathy
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Abstract

A simple way to enforce the Adler zero condition for pion amplitudes in the nuclear medium is to use the Lovelace quantization condition but with modified Regge Slope $α'$ This latter is related to change in the gluon condensate. Increasing nuclear density leads to a relative increase in the Regge Slope $α'$ Denoting this increase by a scale factor $λ$, the drop in the $ρ$-mass, $Δ-N$ mass difference, increase in $ππ$ scattering length, decrease of pion decay constant etc. are simply related to $λ$.

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J. Pasupathy. 1997-03-06. PCAC in Nuclear Medium and the Lovelace-Shapiro-Veneziano formula. https://arxiv.org/abs/nucl-th/9703015

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