The front cover is a photo that shows a levitating spall layer of shock-melted tin. It is one of 16 frames in a proton-radiography movie that shows how a tin disk responds to the shock wave produced by detonating a high explosive beneath the disk. First, the detonation's spherical shock wave bulges the disk (about 2 inches in diameter and 0.25 inch thick). Then, when the compressive shock wave reflects from the disk's upper surface, the shock becomes tensile, dislodging and levitating the spall layer (the "flying saucer"). The shock wave's high pressure and temperature also melt the tin (light gray region connecting the flying saucer and bulge). The movie sequence is shown on pages 14 and 15. Proton radiography is a new diagnostic technique that produces detailed movies of high-speed implosion test.

Research Quarterly showcases Lab's national defense science and technology

The winter 2003 issue of Los Alamos Research Quarterly, a Laboratory publication initiated last fall, is available at www.lanl.gov/quarterly/ and int.lanl.gov/quarterly online and is being distributed to master management and an external audience of Laboratory funding agencies, Congress and partners this month.

Covering a full spectrum of the Laboratory's science and research, this quarterly, full-color publication, aims to communicate the Laboratory's goals and achievements and how they benefit the Lab's neighbors, the nation and the world.

The front cover of the publication shows a levitating spall layer of shock-melted tin. It is one of 16 frames in a proton-radiography movie that shows how a tin disk responds to the shock wave produced by detonating a high explosive beneath the disk. The back cover shows the proton radiograph of a model airplane engine. To read how proton radiography is enhancing the Laboratory's ability to predict the performance of stockpiled nuclear weapons, see the feature article, "Proton Radiography, Sharper 'X-ray Vision' for Hydro Tests," on Page 14.

The study of bone dynamics using Monte Carlo codes and partnering with a local orthopedic surgeon is the topic of "Modeling Bone Remodeling." Using computational simulation techniques that have proven valuable in materials science, mechanical engineering, chemistry and physics, researchers can analyze any complex system that exhibits multiple states and nonlinear competing interactions. This is the case with bones and specifically with osteoporosis.

The article, "Shelf Life Guaranteed," examines how researchers are working to extend the lifetimes of stockpile weapons.

Los Alamos and Sandia national laboratories are collaborating on state-of-the-art, high-end modeling and simulations of the nation's critical infrastructures. In a homeland security effort, the laboratories' simulation capabilities are being put to the task. "Simulation Science, The Key to Understanding National Infrastructures," explains how the labs are helping policymakers understand how the nation's infrastructures work, are linked and can be protected.

In Mesa View, the issue's editorial, Tom Meyer, associate director for strategic research, discusses the foundational role of science, both basic and applied, in achieving Lab missions.

The regular segments, Dateline Los Alamos and Spotlight, Los Alamos in the News, include brief articles on the Lab's array of infrasound detectors and Laboratory researchers who are developing a mathematical model of immunoreceptors - a large and diverse group of proteins that decode regulatory signals. In the spotlight are Senior Fellow Emeritus George Cowan and Laboratory Fellow Louis Rosen who were awarded the Los Alamos National Laboratory Medal. In addition, the Lab has partnered with Los Alamos Commerce and Development Corp. and Spectra Gases by leasing the former Isotopes of Carbon, Oxygen and Nitrogen (ICON) facility to Spectra for its production of high-purity carbon-13, oxygen-17 and oxygen-18. Production of these gases for nuclear medicine and biomedical research will minimize U.S. dependence on foreign sources.

The quarterly's production team is led by Scientific Editor James L. Smith of Materials Technology (MST-6), Judyth Prono, executive editor, and Chris Brigman, art director, both of Communication Arts and Services (IM-1).

Other Headlines