First global antineutrino emission map highlights Earth's energy budget

September 01, 2015

The neutrino and its antimatter cousin, the antineutrino, are the tiniest subatomic particles known to science. These particles are byproducts of nuclear reactions within stars (including our sun), supernovae, black holes and human-made nuclear reactors. They also result from radioactive decay processes deep within the Earth, where radioactive heat and the heat left over from the planet's formation fuels plate tectonics, volcanoes and Earth's magnetic field.

Now, a team of geologists and physicists has generated the world's first global map of antineutrino emissions. The map, published online in the journal Scientific Reports on September 1, 2015, provides an important baseline image of the energy budget of Earth's interior and could help scientists monitor new and existing human-made sources of radiation. The study was led by the National Geospatial-Intelligence Agency with contributions from researchers at the University of Maryland, the University of Hawaii, Hawaii Pacific University and Ultralytics, LLC.

"The interior of Earth is quite difficult to see, even with modern technology. Locating the activity of antineutrinos allows us to create images that our predecessors had only dreamed of," said William McDonough, professor of geology at UMD and a co-author of the study. "This map should prove particularly useful for future studies of processes within the lower crust and mantle."

Neutrinos are notoriously difficult to study; their tiny size and lack of electrical charge enables them to pass straight through matter without reacting. At any given moment, trillions of neutrinos are passing through every structure and living thing on Earth. Luckily, antineutrinos are slightly easier to detect, through a process known as inverse beta decay. Spotting these reactions requires a huge detector the size of a small office building, housed about a mile underground to shield it from cosmic rays that could yield false positive results.

In the current study, the team analyzed data collected from two such detectors--one in Italy and one in Japan--to generate a picture of antineutrino emissions from natural sources deep within Earth. They combined this with data collected by the International Atomic Energy Agency (IAEA) on more than 400 operational nuclear reactors. In total, antineutrinos from these human-made sources accounted for less than 1 percent of the total detected.

"Keeping tabs on nuclear reactors is important for international safety and security. But as a geologist, I'm particularly excited for the potential to learn more about Earth's interior," McDonough said. "This project will allow us to access basic information about the planet's fuel budget across geologic time scales, and might yet reveal new and exciting details on the structure of the deep Earth."

The team plans to make periodic updates to the global antineutrino map in the future, with the help of improved models of Earth's interior and enhanced antineutrino detection technology. Updates to the map will also reflect the construction and decommission of nuclear reactors as appropriate. All told, the maps will provide an up-to-date picture of Earth's overall radioactivity.

"Antineutrinos are only one particle produced by Earth's natural radiation," explained Shawn Usman, R&D Scientist at the National Geospatial-Intelligence Agency and lead author of the study. "The National Geospatial-Intelligence Agency is working with UMD to develop additional radiation maps to characterize the Earth's naturally-occurring gamma and neutron radiation."
This research was supported by the National Geospatial-Intelligence Agency, the National Science Foundation (Award Nos. EAR 1068097 and EAR 1067983), and the U.S. Department of Energy. The content of this article does not necessarily reflect the views of these organizations.

The research paper, "AGM2015: Antineutrino Global Map 2015," Shawn Usman, Glenn Jocher, Stephen Dye, William McDonough and John Learned, was published online September 1, 2015 in the journal Scientific Reports.

Media Relations Contact: Matthew Wright, 301-405-9267,

University of Maryland
College of Computer, Mathematical, and Natural Sciences
2300 Symons Hall
College Park, MD 20742

About the College of Computer, Mathematical, and Natural Sciences

The College of Computer, Mathematical, and Natural Sciences at the University of Maryland educates more than 7,000 future scientific leaders in its undergraduate and graduate programs each year. The college's 10 departments and more than a dozen interdisciplinary research centers foster scientific discovery with annual sponsored research funding exceeding $150 million.

University of Maryland

Related Radiation Articles from Brightsurf:

Sheer protection from electromagnetic radiation
A printable ink that is both conductive and transparent can also block radio waves.

What membrane can do in dealing with radiation
USTC recently found that polymethylmethacrylate (PMMA) and polyvinyl chloride (PVC) can release acidic substance under γ radiation, whose amount is proportional to the radiation intensity.

First measurements of radiation levels on the moon
In the current issue (25 September) of the prestigious journal Science Advances, Chinese and German scientists report for the first time on time-resolved measurements of the radiation on the moon.

New biomaterial could shield against harmful radiation
Northwestern University researchers have synthesized a new form of melanin enriched with selenium.

A new way to monitor cancer radiation therapy doses
More than half of all cancer patients undergo radiation therapy and the dose is critical.

Nimotuzumab-cisplatin-radiation versus cisplatin-radiation in HPV negative oropharyngeal cancer
Oncotarget Volume 11, Issue 4: In this study, locally advanced head and neck cancer patients undergoing definitive chemoradiation were randomly allocated to weekly cisplatin - radiation {CRT arm} or nimotuzumab -weekly cisplatin -radiation {NCRT arm}.

Breaking up amino acids with radiation
A new experimental and theoretical study published in EPJ D has shown how the ions formed when electrons collide with one amino acid, glutamine, differ according to the energy of the colliding electrons.

Radiation breaks connections in the brain
One of the potentially life-altering side effects that patients experience after cranial radiotherapy for brain cancer is cognitive impairment.

Fragmenting ions and radiation sensitizers
The anti-cancer drug 5-fluorouracil (5FU) acts as a radiosensitizer: it is rapidly taken up into the DNA of cancer cells, making the cells more sensitive to radiotherapy.

'Seeing the light' behind radiation therapy
Delivering just the right dose of radiation for cancer patients is a delicate balance in their treatment regime.

Read More: Radiation News and Radiation Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to