Chemist from Los Alamos Will Speak on Exploring the Composition of Planets on March 1

Date: 02-12-2008

Kathleen McPartland
Public Affairs
Kathy Johns
Department of Chemistry

Chemist Samuel M. Clegg, from Los Alamos National Laboratory, will speak at the Northern California American Chemical Society dinner on Saturday, March 1. Clegg will present “Laser Induced Breakdown Spectroscopy: From Terrestrial Carbon Sequestration to Roving Mars.”

The dinner is being hosted by the Department of Chemistry and Biochemistry at California State University, Chico and the Student Affiliates of the American Chemical Society. It will be held in the Bell Memorial Union at 6 p.m. Although this dinner is especially for chemists, Donald Alger, an organizer of the event, said others are welcome. He added, “The topic should be of interest to people with interest in astronomy and geology in terms of discovering the chemical composition of planets in our solar system. It also relates to the questions related to the possibility of life on other planets.”

Laser-Induced Breakdown Spectroscopy (LIBS) is an elemental analysis technique that is currently used to probe a variety of terrestrial and Martian geological samples. It involves focusing a high-power laser onto the surface of a sample. The laser ablates material from the sample surface, generating expanding plasma containing electronically excited ions, atoms and small molecules. These excited species emit light as they relax to lower electronic states at wavelengths indicative of the elements present in the sample.

Clegg and his colleagues have been using LIBS to probe soil core samples to develop a quantitative understanding of how carbon can be terrestrially sequestered. “We are also building a LIBS instrument selected for the NASA Mars Science Laboratory (MSL) Rover scheduled to launch in 2009. The ChemCam instrument will probe samples and determine the elemental composition up to nine meters from the rover mast,” said Clegg. In his presentation, Clegg will describe LIBS, the in situ and remote LIBS instrumentation development, and the quantitative analysis techniques used on geological samples.

Clegg joined the Los Alamos National Laboratory in 2003 and became the Spectroscopy and Materials Team Leader for the Chemistry Division’s Advanced Diagnostics and Instrumentation Group in 2004. He also became the manager of the Laser Induced Breakdown Spectroscopy Research Facility in 2004. Over the last four years, he has developed a broad research portfolio of projects, mostly involving LIBS, funded by NASA, Department of Energy, Department of Defense and Department of Homeland Security.

He earned his PhD from Indiana University under the supervision of Professor Charles Parmenter, where he used laser spectroscopy to study state-to-state energy transfer. He served as a post doctoral research associate in the Department of Geophysical Sciences at the University of Chicago and in the Combustion Research Facility at Sandia National Laboratories. His first professional staff position was with the Air Force Research Laboratory, where he was a principle investigator for the Airborne Laser Program.

For more information about the presentation or to make reservations for the dinner, please contact Kathy Johns at (530) 898-5259.