Tabletop Laser Offers Alternative to Cyclotron

Researchers at the University of Michigan in Ann Arbor and Osaka University in Japan have reported the development of a tabletop laser-based proton accelerator that could replace expensive cyclotrons in cancer treatment and lead to better health care.

A 10-TW, hybrid Ti:sapphire/Nd:phosphate chirped-pulse amplification laser targets thin films of aluminum with a 400-fs pulse at 1053 nm. Protons with energies of up to 1.5 MeV emerge in a tight cone behind the target.

Donald Umstadter, leader of the team, noted that most hospitals cannot afford a $15 million cyclotron, the conventional source of protons for the stereotactic radiotherapy of cancers. He said an inexpensive accelerator also could be used for the on-site preparation of short-lived radioisotope tracers.