Morse index and spectral asymptotics of least-energy solutions to the Choquard equation in planar domains

We investigate the Morse index and spectral asymptotics of least-energy solutions to the planar Choquard equation \begin{equation*} \begin{cases} -Δu = \displaystyle\left(\int_Ω \frac{u^{p+1}(y)}{|x - y|^α}dy\right) u^p & \text{in } Ω, \\ u > 0 & \text{in } Ω, \\ u = 0 & \text{on } \partial Ω, \en