Resurgence in the O(4) sigma model

Understand

We analyze the free energy of the integrable two dimensional O(4) sigma model in a magnetic field.

• We use Volin's method to extract high number (2000) of perturbative coefficients with very high precision.
• The factorial growth of these coefficients are regulated by switching to the Borel transform, where we perform several asymptotic analysis.
• High precision data allowed to identify Stokes constants and alien derivatives with exact expressions.