Celletti A. , Falcolini C.
Status: R
Singularities of Periodic Orbits near Invariant Curves
(3639K, LATeX 2e)

ABSTRACT.  We show numerically, for standard-like maps, how the singularities (in the 
complex parameter) of the function which conjugates the map to a rotation of 
rational period behave when the period goes to an irrational number. 
Furthermore, we propose a numerical method to extrapolate the radius of 
convergence of the series parametrizing the solution of periodic orbits.
The results are compared with analyses performed by Pad\'e approximants,
Greene's method, root criterion and the prediction by renormalization theory.