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تسجيل مستخدم جديدChiral Lagrangians with $Delta(1232)$ to one loop
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We construct the Lorentz-invariant chiral Lagrangians up to the order $mathcal{O}(p^4)$ by including $Delta(1232)$ as an explicit degree of freedom. A full one-loop investigation on processes involving $Delta(1232)$ can be performed with them. For the $piDeltaDelta$ Lagrangian, one obtains 38 independent terms at the order $mathcal{O}(p^3)$ and 318 independent terms at the order $mathcal{O}(p^4)$. For the $pi NDelta$ Lagrangian, we get 33 independent terms at the order $mathcal{O}(p^3)$ and 218 independent terms at the order $mathcal{O}(p^4)$. The heavy baryon projection is also briefly discussed.
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