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arXiv · 2503.17228

Mean value of cubic $L$-funcitons with fixed genus

Ziwei Hong·Zhongqiu Fang
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Abstract

We investigate the mean value of the first moment of primitive cubic $L$-functions over $\mathbb{F}_q(T)$ in the non-Kummer setting. Specifically, we study the sum \begin{equation*} \sum_{\substack{\chi\ primitive\ cubic\\ genus(\chi)=g}}L_q(\frac{1}{2}, \chi), \end{equation*} where $L_q(s,\chi)$ denotes the $L$-function associated with primitive cubic character $\chi$. Using double Dirichlet series, we derive an error term of size $q^{(\frac{7}{8}+\varepsilon)g}$.

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Ziwei Hong, Zhongqiu Fang. 2025-03-21. Mean value of cubic $L$-funcitons with fixed genus. https://arxiv.org/abs/2503.17228

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