New lower bounds on the radius of spatial analyticity for the higher order nonlinear dispersive equation on the real line

In this paper, benefited some ideas of Wang [J. Geom. Anal. 33, 18 (2023)] and Dufera et al. [J. Math. Anal. Appl. 509, 126001 (2022)], we investigate persistence of spatial analyticity for solution of the higher order nonlinear dispersive equation with the initial data in modified Gevrey space. More precisely, using the contraction mapping principle, the bilinear estimate as well as approximate conservation law, we establish the persistence of the radius of spatial analyticity till some time delta. Then, given initial data that is analytic with fixed radius sigma 0, we obtain asymptotic lower bound sigma(t)>= c|t|-12, for large time t >= delta. This result improves earlier ones in the literatures, such as Zhang et al. [Discrete Contin. Dyn. Syst. B 29, 937-970 (2024)], Huang-Wang [J. Differ. Equations 266, 5278-5317 (2019)], Liu-Wang [Nonlinear Differ. Equations Appl. 29, 57 (2022)], Wang [J. Geom. Anal. 33, 18 (2023)] and Selberg-Tesfahun [Ann. Henri Poincar & eacute; 18, 3553-3564 (2017)].