The lollipop graph is determined by its Q-spectrum

A graph G is said to be determined by its Q-spectrum if with respect to the signless Laplacian matrix Q , any graph having the same spectrum as G is isomorphic to G . The lollipop graph, denoted by H n , p , is obtained by appending a cycle C p to a pendant vertex of a path P n − p . In this paper, it is proved that all lollipop graphs are determined by their Q -spectra.