1. Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
2. Physics Department, University of Rochester, Rochester, New York 14627, USA
3. Institute of Optics, University of Rochester, Rochester, New York 14627, USA
4. GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Tècnico, Universidade de Lisboa, Lisbon, Portugal