New type of solutions for the critical polyharmonic equation

In this paper, we consider the following critical polyharmonic equation \begin{align*}%\label{abs} ( -Δ)^m u+V(|y’|,y’')u=u^{m^-1},\quad u>0, \quad y=(y’,y’')\in $\mathbb{R}$^3\times $\mathbb{R}$^{N-3}, \end{align} where $m^{\ast }=\frac{2N}{N-2m}$, $N>4m+1$, $m\in {\mathbb{N}}^{+}$, and $V(\mathrm{\mid }{y}^{\mathrm{\prime }}\mathrm{\mid },y^{\mathrm{\prime }\mathrm{\prime }})$ is a bounded nonnegative function in ${\mathbb{R}}^{+}\times {\mathbb{R}}^{N-3}$. By using the reduction argument and local Pohouzaev identities, we prove that if $r^{2m}V(r,y^{\mathrm{\prime }\mathrm{\prime }})$ has a stable critical point $(r_0,y_0^{\mathrm{\prime }\mathrm{\prime }})$ with $r_0>0$ and $V(r_0,y_0^{\mathrm{\prime }\mathrm{\prime }})>0$, then the above problem has a new type of solutions, which concentrate at points lying on the top and the bottom circles of a cylinder.