The weight distribution of a family of p-ary cyclic codes

Let m, k be positive integers, p be an odd prime and $\pi $ be a primitive element of $\mathbb{F}_{p^m}$. In this paper, we determine the weight distribution of a family of cyclic codes $\mathcal{C}_t$ over $\mathbb{F}_p$, whose duals have two zeros $\pi^{-t}$ and $-\pi^{-t}$, where $t$ satisfies $t\equiv \frac{p^k+1}{2}p^\tau \ ({\rm mod}\ \frac{p^m-1}{2}) $ for some $\tau \in \{0,1,\cdots, m-1\}$.