BYU statistician calculates uncertainty of aging U.S. nukes

Aug 11, 2011

( -- How do you test a not-so-young nuclear stockpile for the effects of age when you can’t detonate any for the sake of finding out?

The U.S. government has not conducted live nuclear tests since the early 1990s, but a BYU scientist is providing some solid answers – without setting off any weapons.

In a new study for the journal Technometrics, statistics professor Shane Reese and his former colleagues at Los Alamos National Laboratories calculated the certainty of America’s nuclear weapons working if they’re supposed to (and not working when they’re not supposed to).

“The purpose is to perform science experiments to get at the efficacy of a weapons system that has exceeded its original design life and certainly experienced some effects due to aging,” Reese said.

With non-nuclear weapons, reliability testing is a simple matter of going out in the desert every so often and firing a few rounds.

But with their nuclear arsenal, the government instead selects 11 weapons at random from each of nine stockpiles. Scientists completely dismantle the sampled weapons and inspect every component for signs of degradation. More details about the process can be found here.

Since that gets expensive, the point of Reese’s study is to compare how the level of reliability would change if fewer nukes were inspected each year – or none at all.

Using sophisticated statistical techniques, Reese and his coauthors arrived at two main conclusions. If the government cut monitoring in half, confidence in the system’s reliability would drop from 95 to 80 percent within seven years. And if monitoring stopped altogether, the reliability would drop to almost the same odds that you’d find with flipping a coin.

“It’s commonly suggested that we turn off data collection or slow down data collection,” Reese said. “When you are fairly certain that you have an aging stockpile, our study shows that ignoring the problem by not collecting data is a huge mistake.”

The project is personally fulfilling to Reese because his father-in-law lived downwind from the Nevada Test Site and ultimately died from the effects of radiation exposure. Statistical research like this reduces pressure to resume live tests.

“I do think what we’re doing has an impact and removes the need for gathering data using traditional testing that has adverse impacts on human and environmental health,” Reese said. “It at least helps us manage the uncertainty.”

The National Academy of Sciences has also invited Reese to participate in a panel that will analyze how to destroy biological and chemical weapon stockpiles in a way that’s safe for the staff involved and for the environment.

Explore further: Adding uncertainty to improve mathematical models

add to favorites email to friend print save as pdf

Related Stories

Second Z plutonium 'shot' safely tests materials for NNSA

May 12, 2011

The National Nuclear Security Administration (NNSA) today announced that researchers from Sandia and Los Alamos national laboratories have completed their second experiment in the past six months at Sandia’s ...

Study finds 'masculine' women get more promotions at work

Jan 27, 2011

Women who demonstrate stereotypical masculine traits should be mindful of their behavior if they want to get ahead in the workplace. That is the finding of researchers at George Mason University and Stanford University who ...

DNA 'off switch' may reverse premature aging

Jun 15, 2011

The secret to preventing or reversing premature aging may be found in a DNA “off switch” that humans share with common yeast, according to new research from the University of Toronto.

Taking the 'waste' out of nuclear waste

Jun 01, 2011

While spent nuclear fuel continues to pile up by the ton across the United States, UC Irvine’s Mikael Nilsson says the solution is clear: recycle it at the commercial nuclear power plants that create ...

Recommended for you

Self-made billionaires more likely to give than inheritors

1 minute ago

A study by economists at the University of Southampton suggests that billionaires who have built their own fortunes are more likely to pledge to donate a large portion of their wealth to charities, than those who are heirs ...

Research band at Karolinska tuck Dylan gems into papers

12 hours ago

( —A 17-year old bet among scientists at the Karolinska Institute has been a wager that whoever wrote the most articles with Dylan quotes before they retired would get a free lunch. Results included ...

Adding uncertainty to improve mathematical models

13 hours ago

Mathematicians from Brown University have introduced a new element of uncertainty into an equation used to describe the behavior of fluid flows. While being as certain as possible is generally the stock and ...

At the interface of math and science

13 hours ago

In popular culture, mathematics is often deemed inaccessible or esoteric. Yet in the modern world, it plays an ever more important role in our daily lives and a decisive role in the discovery and development ...

User comments : 0