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arXiv · 2510.01601

On the Tamagawa number conjecture for modular forms twisted by anticyclotomic Hecke characters

Takamichi Sano
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Abstract

Let $f \in S_{2r}(\Gamma_0(N))$ be a normalized newform of weight $2r$ which is good at $p$. Let $K$ be an imaginary quadratic field of class number one in which every prime divisor of $pN$ splits. Let $\chi$ be an anticyclotomic Hecke character of $K$ which is crystalline at the primes above $p$ and such that $L(f,\chi,r)\neq 0$. We prove that the Tamagawa number conjecture for the critical value $L(f,\chi,r)$ follows from the Iwasawa main conjecture for the Bertolini-Darmon-Prasanna $p$-adic $L$-function.

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Takamichi Sano. 2025-10-02. On the Tamagawa number conjecture for modular forms twisted by anticyclotomic Hecke characters. https://arxiv.org/abs/2510.01601

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