diff --git a/pyfstat/mcmc_based_searches.py b/pyfstat/mcmc_based_searches.py
index 9e12524ac2c3fcbe1a4af17e34284c5f18fa7bc2..06445f8cf9c0c3e42dd7234892c0cc1e4a5b5903 100644
--- a/pyfstat/mcmc_based_searches.py
+++ b/pyfstat/mcmc_based_searches.py
@@ -998,7 +998,7 @@ class MCMCSearch(core.BaseSearchClass):
                                      color="C3", alpha=alpha,
                                      lw=lw)
                         axes[i].axvline(xoffset+convergence_idx,
-                                        color='k', ls='--', lw=0.25)
+                                        color='k', ls='--', lw=0.5)
                     axes[i].plot(xoffset+idxs[burnin_idx:],
                                  cs[burnin_idx:]-subtractions[i],
                                  color="k", alpha=alpha, lw=lw)