Tighter monogamy and polygamy relations using R{e}nyi-$alpha$ entropy

We investigate monogamy relations related to the R{e}nyi-$alpha$ entanglement and polygamy relations related to the R{e}nyi-$alpha$ entanglement of assistance. We present new entanglement monogamy relations satisfied by the $mu$-th power of R{e}nyi-$alpha$ entanglement with $alphain[sqrt{7}-1)/2,(sqrt{13}-1)/2]$ for $mugeqslant2$, and polygamy relations satisfied by the $mu$-th power of R{e}nyi-$alpha$ entanglement of assistance with $alphain[sqrt{7}-1)/2,(sqrt{13}-1)/2]$ for $0leqmuleq1$. These relations are shown to be tighter than the existing ones.