13. Kontsevich-Witten series with $\hbar$
Proposed by Xavier Blot:Write down the Kontsevich-Witten series with $\hbar$. What is the geometric meaning of the new coefficients? For $\epsilon=0$, these come from double Hurwitz numbers. Conjecturally, some of them are of the form $\lambda \cdot \lambda \cdot (\psi\text{-classes})$.
Cite this as: AimPL: Double ramification cycles and integrable systems, available at http://aimpl.org/doubleramific.