1. Brazilian Synchrotron Light Laboratory, Brazilian Center for Research in Energy and Materials 1 , R. Giuseppe M. Scolfaro, 10,000 Campinas, Brazil
2. Gleb Wattaghin Physics Institute (IFGW), Campinas State University (Unicamp) 2 , Campinas, Brazil
3. Department of Physics, Federal University of São Carlos 3 , São Carlos, Brazil