PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Iowa State physicists explain the long, useful lifetime of carbon-14

Iowa State physicists explain the long, useful lifetime of carbon-14
2011-05-27
(Press-News.org) AMES, Iowa – The long, slow decay of carbon-14 allows archaeologists to accurately date the relics of history back to 60,000 years.

And while the carbon dating technique is well known and understood (the ratio of carbon-14 to other carbon isotopes is measured to determine the age of objects containing the remnants of any living thing), the reason for carbon-14's slow decay has not been understood. Why, exactly, does carbon-14 have a half-life of nearly 6,000 years while other light atomic nuclei have half-lives of minutes or seconds? (Half-life is the time it takes for the nuclei in a sample to decay to half the original amount.)

"This has been a very significant puzzle to nuclear physicists for several decades," said James Vary, an Iowa State University professor of physics and astronomy. "And the underlying reason turned out to be a fairly exotic one."

The reason involves the strong three-nucleon forces (a nucleon is either a neutron or a proton) within each carbon-14 nucleus. It's all about the simultaneous interactions among any three nucleons and the resulting influence on the decay of carbon-14. And it's no easy task to simulate those interactions.

In this case, it took about 30 million processor-hours on the Jaguar supercomputer at Oak Ridge National Laboratory in Tennessee. Jaguar has a peak performance of 2.3 quadrillion calculations per second, a speed that topped the list of the world's top 500 supercomputers when the carbon-14 simulations were run.

The research project's findings were recently published online by the journal Physical Review Letters.

Vary and Pieter Maris, an Iowa State research staff scientist in physics and astronomy, are the lead authors of the paper. Collaborating on the paper are Petr Navratil of TRIUMF (Canada's National Laboratory for Particle and Nuclear Physics in Vancouver) and the Lawrence Livermore National Laboratory in California; Erich Ormand of Lawrence Livermore National Lab; plus Hai Ah Nam and David Dean of Oak Ridge National Lab. The research was supported by contracts and grants from the U.S. Department of Energy Office of Science.

Vary, in explaining the findings, likes to remind people that two subatomic particles with different charges will attract each other. Particles with the same charges repel each other. Well, what happens when there are three particles interacting that's different from the simple addition of their interactions as pairs?

The strong three-nucleon interactions are complicated, but it turns out a lot happens to extend the decay of carbon 14 atoms.

"The whole story doesn't come together until you include the three-particle forces," said Vary. "The elusive three-nucleon forces contribute in a major way to this fact of life that carbon-14 lives so long."

Maris said the three-particle forces work together to cancel the effects of the pairwise forces governing the decay of carbon-14. As a result, the carbon-14 half-life is extended by many orders of magnitude. And that's why carbon-14 is a very useful tool for determining the age of objects.

To get that answer, Maris said researchers needed a billion-by-billion matrix and a computer capable of handling its 30 trillion non-zero elements. They also needed to develop a computer code capable of simulating the entire carbon-14 nucleus, including the roles of the three-nucleon forces. Furthermore, they needed to perform the corresponding simulations for nitrogen-14, the daughter nucleus of the carbon-14 decay. And, they needed to figure out how the computer code could be scaled up for use on the Jaguar petascale supercomputer.

"It was six months of work pressed into three months of time," Maris said.

But it was enough for the nuclear physicists to explain the long half-life of carbon-14. And now they say there are more puzzles to solve:

"Everybody now knows about these three-nucleon forces," Vary said. "But what about four-nucleon forces? This does open the door for more study."



INFORMATION:


[Attachments] See images for this press release:
Iowa State physicists explain the long, useful lifetime of carbon-14

ELSE PRESS RELEASES FROM THIS DATE:

Students who struggle with math may have a neurocognitive disorder called dyscalculia

2011-05-27
Students who struggle to learn mathematics may have a neurocognitive disorder that inhibits the acquisition of basic numerical and arithmetic concepts, according to a new paper by University of Minnesota and British researchers. Called developmental dyscalculia, the disorder affects roughly the same number of people as dyslexia but has received much less attention (and research funding). The paper by University of Minnesota Educational Psychology assistant professor Sashank Varma and his British colleagues that shines a light on the causes of and interventions for dyscalculia ...

Study shows brain's response to sadness can predict relapses into depression

2011-05-27
A University of Toronto study shows that when formerly depressed people experience mild states of sadness, their brain's response can predict if they will become depressed again. "Part of what makes depression such a devastating disease is the high rate of relapse," says Norman Farb, a PhD psychology student and lead author of the study. "However, the fact that some patients are able to fully maintain their recovery suggests the possibility that different responses to the type of emotional challenges encountered in everyday life could reduce the chance of relapse." Farb ...

Get Your Solar Inverter 'Fix' from Fronius Australia with Business Review Australia

Get Your Solar Inverter Fix from Fronius Australia with Business Review Australia
2011-05-27
Business Review Australia takes a look at Fronius Australia. Austrian-based Fronius International has been developing and manufacturing welding equipment and battery technology for over half a century. Since 1995, Fronius expanded its operations to include solar power electronics. With operations spanning the globe, Fronius inverters have been available to the Australian market since 1992. Fronius International realized the growing potential of the Australian solar power market and opened a solar electronics division in Melbourne in October 2010. Fronius Australia now ...

Aging, obsolete cells prime the lungs for pneumonia

Aging, obsolete cells prime the lungs for pneumonia
2011-05-27
SAN ANTONIO (May 26, 2011) — Community-acquired pneumonia is the leading cause of infectious death among the elderly. Newly published research from The University of Texas Health Science Center San Antonio suggests why older people are vulnerable and offers a possible defense. The researchers found that when it comes to aging and pneumonia, one bad apple can ruin the barrel. Lung cells that were supposed to die due to DNA damage — but didn't — were 5 to 15 times more susceptible to invasion by pneumonia-causing bacteria. These bad apples also increased the susceptibility ...

TGen study identifies compounds that could slow down Alzheimer's disease

2011-05-27
PHOENIX, Ariz. — May 26, 2011 — A family of naturally occurring plant compounds could help prevent or delay memory loss associated with Alzheimer's disease, according to a new study by the Translational Genomics Research Institute (TGen). Beta-carboline alkaloids could potentially be used in therapeutic drugs to stop, or at least slow down, the progressively debilitating effects of Alzheimer's, according to the study published recently in the scientific journal Public Library of Science (PLoS) One. One of these alkaloids, called harmine, inhibits a protein known as ...

Common transplant drug inhibits breast cancer growth, UNC laboratory study shows

2011-05-27
Tacrolimus, a drug that is commonly used to prevent organ transplantation rejection, inhibits breast cancer growth in pre-clinical studies. The finding from UNC scientists was reported in the May 26th PLoS ONE. Nancy Klauber-DeMore, MD, associate professor of surgery, said, " We now have a rationale for performing human clinical trials to determine if Tacrolimus reduces breast cancer growth in humans. Since Tacrolimus is already an FDA-approved drug, the safety and toxicity profile is known, which means that Tacrolimus could potentially go directly into a later stage ...

Bruce Marks to Speak at US-Russia Business Council Forum in London

Bruce Marks to Speak at US-Russia Business Council Forum in London
2011-05-27
Leading law firm, Marks & Sokolov, is pleased to announce Managing Director, Bruce S. Marks, will moderate a prestigious panel at the 3rd US Russia Business Council Legal Forum. A world leader in US, Russian and Ukrainian law and litigation, Bruce S. Marks brings a unique and important perspective to the forum. Taking place in London on June 9th, 2011, the forum will gather the world's leading practitioners in US Russian commercial legal matters. Bruce S. Marks will moderate a panel entitled 'Legal Reform and the Courts in Russia'. It's more than two years since ...

Current test-based incentive programs have not consistently raised

2011-05-27
WASHINGTON — Despite being used for several decades, test-based incentives have not consistently generated positive effects on student achievement, says a new report from the National Research Council. The report examines evidence on incentive programs, which impose sanctions or offer rewards for students, teachers, or schools on the basis of students' test performance. Federal and state governments have increasingly relied on incentives in recent decades as a way to raise accountability in public education and in the hope of driving improvements in achievement. School-level ...

People with body-image disorders process 'big picture' visual information abnormally

2011-05-27
People suffering from body dysmorphic disorder, or BDD — a severe mental illness characterized by debilitating misperceptions that one appears disfigured and ugly — process visual information abnormally, even when looking at inanimate objects, according to a new UCLA study. First author Dr. Jamie Feusner, a UCLA assistant professor of psychiatry, and colleagues found that patients with the disorder have less brain activity when processing holistic visual elements that provide the "big picture," regardless of whether that picture is a face or an object. The research ...

5 new hot spots where medicine and technology will converge

5 new hot spots where medicine and technology will converge
2011-05-27
Medicine and technology are converging in patient care at a faster pace than most people realize. Space age advancements from point-of-care health technologies like telemedicine to medical robots performing surgery are fast becoming commonplace in many hospitals. What's next? Ask NJIT Distinguished Professor Atam Dhawan, an electrical engineer and associate dean of the NJIT Albert Dorman Honors College, chair of the the IEEE emerging technology committee, and workshop chair for the upcoming 33rd IEEE Engineering in Medicine and Biology Society (EMBS) Annual International ...

LAST 30 PRESS RELEASES:

New jab protects babies from serious lung infection, study shows

July Tip Sheet from Sylvester Comprehensive Cancer Center

Current application status and innovative development of surgical robot

Counterfeited in China: New book assesses state of industry and its future

Machine learning reveals historical seismic events in the Yellowstone caldera

First analyses of Myanmar earthquake conclude fault ruptured at supershear velocity

Curved fault slip captured on CCTV during Myanmar earthquake

Collaboration rewarded for work to further deployment of batteries in emerging economies

Heart-healthy habits also prevent cancer, Alzheimer’s, COPD, other diseases, Emory study finds

Scientists will use a $1M grant to build a support system addressing sea level rise and flooding in South Florida

New research examines how pH impacts the immune system

Inhaled agricultural dust disrupts gut health

New study reveals hidden regulatory roles of “junk” DNA

Taking the sting out of ulcerative colitis

Deep life’s survival secret: Crustal faulting generates key energy sources, study shows

Idaho National Laboratory to lead advancements in US semiconductor manufacturing

AI-assisted sorting, other new technologies could improve plastic recycling

More than just larks and owls!

Call for nominations: 2026 Dan David Prize

New tool gives anyone the ability to train a robot

Coexistence of APC and KRAS mutations in familial adenomatous polyposis and endometrial cancer: A mini-review with case-based perspective

First global-to-local study reveals stark health inequalities from COVID-19 in 2020–2021

rcssci: Simplifying complex data relationships with enhanced visual clarity

Why some ecosystems collapse suddenly—and others don’t

One-third of U.S. public schools screen students for mental health issues

GLP-1 RA use and survival among older adults with cancer and type 2 diabetes

Trends in physician exit from fee-for-service Medicare

Systematic investigation of tumor microenvironment and antitumor immunity with IOBR

Common feature between forest fires and neural networks reveals the universal framework underneath

New R package revolutionizes gene set enrichment analysis visualization for biomedical research

[Press-News.org] Iowa State physicists explain the long, useful lifetime of carbon-14