diff --git a/src/common.h b/src/common.h
index 95a3611..5e6f4e8 100644
--- a/src/common.h
+++ b/src/common.h
@@ -7,6 +7,6 @@
 #define M (0.5*Rs)
 #define R0 (15*Rs)
 #define f(r) ((1.0-Rs/((double)r)))
-#define bmin (1.5*sqrt(3.0))
+#define bmin (1.5*sqrt(3.0))+1e-5
 #define THETAERROR 100000