P. J. Mallozzi

Laser‐generated plasmas as a source of x rays for medical applications

High‐resolution medical radiographs have been produced with a laser‐generated plasma x‐ray source. The nanosecond pulse width is capable of arresting biological motion. In addition, the soft x rays from this source have been transmitted through a new type of x‐ray beam handling device, the x‐ray pipe, which is an x‐ray analogue of the conventional light pipe. This may allow new medical applications such as channeling soft x rays to internal locations of the body without damaging intervening tissue.

Laser-EXAFS: Fast Extended X-ray Absorption Fine Structure Spectroscopy with a Single Pulse of Laser-Produced X-rays

The extended x-ray absorption fine structure (EXAFS) spectrum of aluminum has been measured with a nanosecond pulse of soft x-rays generated by a laser-produced plasma. This technique provides a practical alternative to synchrotorn radiation for the acquisition of EXAFS data. It also provides a unique capability for the analysis of molecular structure in highly transient chemical species.

Laser Plasma X-Ray Source Optimization For Lithography

The laser-plasma X-ray source has been evaluated for submicrometer X-ray lithography exposure machines. X-ray lithography systems based on commercially available lasers of reasonable cost appear to be feasible. Such machines would make full wafer exposures of silicon slices with a throughput consistent with current manufacturing requirements.

Amplified−spontaneous−emission suppressor for Q−switched lasers

A passive device for suppressing amplified spontaneous emission in Q−switched lasers has been developed. The technique is applicable to lasers of any aperture.

Laser‐EXAFS: Laboratory EXAFS with a nanosecond pulse of laser‐produced X‐rays

Laser‐produced x‐rays are a promising alternative to synchrotron radiation for the measurement of EXAFS spectra. Experiments to date indicate that the K‐edge EXAFS spectra of elements with atomic numbers up to about Z = 20, and L‐edge spectra of elements with atomic numbers up to about Z = 40, can be obtained with a single nanosecond pulse of x‐rays emitted by a laser‐produced plasma. The technique shows promise of providing single‐shot EXAFS spectra for the remaining elements as well, with the use of advanced laser systems that are available today. The x‐ray pulse can be synchronized easily with an external optical or electrical perturbation of the sample, thereby providing a unique capability for recording EXAFS spectra of highly transient species having lifetimes the order of a nanosecond.

Real-Time Diagnostics for a Laser Fusion System

An automated diagnostic system has been developed and installed on a multibeam laser for fusion research. Laser-beam phase and intensity profile, focal-spot profile, pulse width, beam energy, and other laser parameters are measured at a number of points in the system. Data from the optical and voltage sensing elements are processed by an on-line mini-computer and the information is presented in graphic, pictorial, and tabular form. The processed information is used

Current status of laser fusion research at Battelle.

The central research discussed is the analysis and control of laser-produced high-Z plasmas. Research consisting mainly of laser development, model and code development, and target irradiations is described. Some medical applications of the research are also mentioned. (MOW)

A New Method for Isolating Q‐Switched Lasers

A laser‐isolator device capable of protecting Q‐switched lasers from target backscatter has been designed and tested. The technique is readily applicable to lasers of any aperture.