Tropical Refined Curve Counting with Descendants

We prove a <i>q</i>-refined tropical correspondence theorem for higher genus descendant logarithmic Gromov-Witten invariants with a <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>λ</mml:mi> <mml:mi>g</mml:mi></mml:msub> </mml:math> class in toric surfaces. Specifically, a generating series of such logarithmic Gromov-Witten invariants agrees with a <i>q</i>-refined count of rational tropical curves satisfying higher valency conditions. As a corollary, we obtain a geometric proof of the deformation invariance of this tropical count. In particular, our results give an algebro-geometric meaning to the tropical count defined by Blechman and Shustin. Our strategy is to use the logarithmic degeneration formula, and the key new technique is to reduce to computing integrals against double ramification cycles and connect these integrals to the non-commutative KdV hierarchy.