New knowledge about 'flawed' diamonds could speed the development of diamond-based quantum computers

ScienceDaily (Oct. 12, 2011) — A University at Buffalo-led research team has established the presence of a dynamic Jahn-Teller effect in defective diamonds, a finding that will help advance the development of diamond-based systems in applications such as quantum information processing.

"We normally want things to be perfect, but defects are actually very important in terms of electronic applications," said Peihong Zhang, the UB associate professor of physics who led the study. "There are many proposals for the application of defective diamonds, ranging from quantum computing to biological imaging, and our research is one step toward a better understanding of these defect systems."

The research was published online Sept. 30 in Physical Review Letters.

The findings deal with diamonds whose crystal structure contains a particular defect: a nitrogen atom that sits alongside a vacant space in an otherwise perfect lattice made only of carbon.

At the point of the imperfection -- the so-called "nitrogen-vacancy center" -- a single electron can jump between different energy states. (The electron rises to a higher, "excited" energy state when it absorbs a photon and falls back to a lower energy state when it emits a photon).

Understanding how the diamond system behaves when the electron rises to an excited state called a "3E" state is critical to the success of such proposed applications as quantum computing.

The problem is that at the nitrogen-vacancy center, the 3E state has two orbital components with exactly the same energy -- a configuration that is inherently unstable.

In response, the lattice "stabilizes" by rearranging itself. Atoms near the nitrogen-vacancy center move slightly, resulting in a new geometry that has a lower energy and is more stable.

This morphing is known as the Jahn-Teller effect, and until recently, the effect's precise parameters in defective diamonds remained unknown.

Zhang and colleagues from the Rensselaer Polytechnic Institute in Troy, N.Y., are the first to crack that mystery. Using UB's supercomputing facility, the Center for Computational Research, the team conducted calculations that reveal how, exactly, the diamond lattice distorts.

Their findings align with experimental results from other research studies, and shed light on important topics such as how long an excited electron at the nitrogen-vacancy center will stay coherently at a higher energy state.

The UB-Rensselaer study was funded by the Department of Energy.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University at Buffalo.

Journal Reference:

Tesfaye Abtew, Y. Sun, Bi-Ching Shih, Pratibha Dev, S. Zhang, Peihong Zhang. Dynamic Jahn-Teller Effect in the NV- Center in Diamond. Physical Review Letters, 2011; 107 (14) DOI: 10.1103/PhysRevLett.107.146403

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Astrophysics and extinctions: News about planet-threatening events

ScienceDaily (Oct. 7, 2011) — Space is a violent place. If a star explodes or black holes collide anywhere in our part of the Milky Way, they'd give off colossal blasts of lethal gamma-rays, X-rays and cosmic rays and it's perfectly reasonable to expect Earth to be bathed in them. A new study of such events has yielded some new information about the potential effects of what are called "short-hard" interstellar radiation events.

Several studies in the past have demonstrated how longer high-energy radiation bursts, such as those caused by supernovae, and extreme solar flares can deplete stratospheric ozone, allowing the most powerful and damaging forms of ultraviolet radiation to penetrate to Earth's surface. The probability of an event intense enough to disrupt life on the land or in the oceans becomes large, if considered on geological timescales. So getting a handle on the rates and intensities of such events is important for efforts to connect them to extinctions in the fossil record.

"We find that a kind of gamma ray burst -- a short gamma ray burst -- is probably more significant than a longer gamma ray burst," said astrophysicist Brian Thomas of Washburn University. Improved and accumulated data collected by the SWIFT satellite, which catches gamma ray bursts in action in other galaxies, is providing a better case for the power and threat of the short bursts to life on Earth.

The shorter bursts are really short: less than one second long. They are thought to be caused by the collision of two neutron stars or maybe even colliding black holes. No one is certain which. What is clear is that they are incredibly powerful events.

"The duration is not as important as the amount of radiation," said Thomas. If such a burst were to happen inside the Milky Way, it its effects would be much longer lasting to Earth's surface and oceans.

"What I focused on was the longer term effects," said Thomas. The first effect is to deplete the ozone layer by knocking free oxygen and nitrogen atoms so they can recombine into ozone-destroying nitrous oxides. These long-lived molecules keep destroying ozone until they rain out. "So we see a big impact on the ozone layer."

Those effects are likely to have been devastating for many forms of life on the surface -- including terrestrial and marine plants which are the foundation of the food web.

Based on what is seen among other galaxies, these short bursts, it seems that they occur in any given galaxy at a rate of about once per 100 million years. If that is correct, then it's very likely that Earth has been exposed to such events scores of times over its history. The question is whether they left a calling card in the sky or Earth's geological record.

Astronomical evidence is not likely, said Thomas, because the galaxy spins and mixes pretty thoroughly every million years, so any remnants of blasts are probably long gone from view. There might, however, be evidence in the ground here on Earth, he said. Some researchers are looking at the isotope iron-60, for instance, which has been argued as a possible proxy for radiation events.

If isotopes like iron-60 can reveal the strata of the events, it then becomes a matter of looking for extinction events that correlate and seeing what died and what survived -- which could shed more light on the event itself.

"I work with some paleontologists and we try to look for correlations with extinctions, but they are skeptical," said Thomas. "So if you go and give a talk to paleontologists, they are not quite into it. But to astrophysicists, it seems pretty plausible."

Thomas will be presenting his work on October 9, 2011, at the annual meeting of the Geological Society of America in Minneapolis. This work was supported by the NASA Astrobiology: Exobiology and Evolutionary Biology Program.

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Note: If no author is given, the source is cited instead.

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Measuring elusive solar neutrinos flowing through the Earth, physicists learn more about the sun

ScienceDaily (Oct. 11, 2011) — Using one of the most sensitive neutrino detectors on the planet, an international team including physicists Laura Cadonati and Andrea Pocar at the University of Massachusetts Amherst are now measuring the flow of solar neutrinos reaching earth more precisely than ever before. The detector probes matter at the most fundamental level and provides a powerful tool for directly observing the sun's composition.

Pocar, Cadonati and colleagues report in the current issue of Physical Review Letters that the Borexino instrument has now measured with high precision the flux of the beryllium seven (7Be) solar neutrino, abundant, low-energy particles once below the observable threshold. With this advance, they can now precisely study the behavior of solar neutrinos with kinetic energy below 1 megaelectron volt (MeV). Borexino scientists also recently reported the first observation of neutrinos produced in a little-studied solar nuclear process known as proton-electron-proton, or pep, and set of stringent limit on reactions involving carbon, nitrogen and oxygen (the CNO cycle) in the sun.

Cadonati says, "Borexino is the only detector capable of observing the entire spectrum of solar neutrinos at once. Our results, the culmination of 20 years of research, greatly narrow the observation precision. The data confirm the neutrino oscillations, flavor changes and flow predicted by models of the sun and particle physics."

Of particular interest, Pocar and Cadonati note, is the Borexino instrument's ability to more thoroughly test neutrino oscillation parameters, allowing an exploration of their characteristic non-zero mass, which does not fit the Standard Model of particle physics. "Our data can tell us about fundamental micro physics at the particle level," says Cadonati. "Borexino is using neutrinos to explore the interior of the sun, looking for new, exciting clues to the mysteries of the universe we cannot see." Pocar adds, "Our detector provides stringent tests of the three-neutrino oscillations model."

Solar neutrinos are produced in nuclear processes and radioactive decays of several elements during fusion reactions at the sun's core. As many as 65 billion of them stream out of the sun and hit every square centimeter of Earth's surface [or 420 billion every square inch] every second. But because they only interact through the nuclear weak force they pass through matter unaffected, making them very difficult to detect and to distinguish from the trace nuclear decays of ordinary materials. The weak force is one of the four fundamental forces of nature, with gravity, electromagnetism and the strong force. It is responsible for the radioactive decay of unstable subatomic particles, with a short range of influence, about 1 percent of the diameter of a typical atomic nucleus.

The Borexino instrument, housed far beneath Italy's Apennine Mountains, detects neutrinos as they interact with an ultra-pure organic liquid scintillator at the center of a large sphere surrounded by 2,000 tons of water. Its great depth and many onion-like protective layers maintain the core as the most radiation-free medium on the planet.

There are three neutrino types, or "flavors": electron, muon and tau. Those produced in the sun are the electron type. As they travel away from their birthplace, they oscillate, or change from one flavor to another. A detector like Borexino can observe all three types in real time and measures each one's energy, but it cannot distinguish between them. It's more sensitive to the electron type so they are more likely to be seen.

The 7Be neutrino flux now being detected by Borexino is predicted by the standard solar model to make up about 10 percent of solar flow, Cadonati says. Earlier instruments in Canada and Japan designed to detect higher-energy neutrinos had already observed evidence of their flavor oscillations, probing 1/10,000 of the solar neutrino flux and their oscillations as they travel through solar matter. However, without data in the low-energy range as scanned by Borexino, physicists were not able to confirm the specific energy-dependent effect of solar neutrino oscillations. Borexino has now filled this gap and for the first time observed evidence of neutrino oscillation in vacuum, as they travel between the sun and Earth.

Pocar says that from the astrophysics angle, Borexino's ability to conduct "precision physics" experiments and collect a large number of observations, with concomitant higher statistical power, is yielding data that show how our sun works. As for the possibility of discovering a new kind of neutrino coming from the sun, which is allowed by some theoretical extensions to the Standard Model of particle physics, he adds, "You always have the hope of seeing surprises, some small deviation from the expectations. And this you can only have if your accuracy and precision are good enough to see very small variations."

In a companion paper, the Borexino team says their 7Be solar neutrino flux measurements show no flow differences between day and night. Some had hypothesized that one might exist because neutrinos pass through Earth's bulk at night. But Pocar says, "The traverse through the Earth seems not to change neutrinos' flavor."

In the future, the researchers hope to identify the origin of every neutrino type coming from the sun, particularly to assess the relative levels of carbon, nitrogen and oxygen there, to deepen understanding of how the sun evolved and how its workings are related to that of larger stars.

Borexino is an international collaboration funded by the U.S. National Science Foundation, the Italian National Institute for Nuclear Physics (INFN) which manages the Gran Sasso labs and similar organizations in Germany, Russia and Poland.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Massachusetts at Amherst.

Journal Reference:

G. Bellini, J. Benziger, D. Bick, S. Bonetti, G. Bonfini, M. Buizza Avanzini, B. Caccianiga, L. Cadonati, F. Calaprice, C. Carraro, P. Cavalcante, A. Chavarria, D. D’Angelo, S. Davini, A. Derbin, A. Etenko, K. Fomenko, D. Franco, C. Galbiati, S. Gazzana, C. Ghiano, M. Giammarchi, M. Goeger-Neff, A. Goretti, L. Grandi, E. Guardincerri, S. Hardy, Aldo Ianni, Andrea Ianni, V. Kobychev, D. Korablev, G. Korga, Y. Koshio, D. Kryn, M. Laubenstein, T. Lewke, E. Litvinovich, B. Loer, F. Lombardi, P. Lombardi, L. Ludhova, I. Machulin, S. Manecki, W. Maneschg, G. Manuzio, Q. Meindl, E. Meroni, L. Miramonti, M. Misiaszek, D. Montanari, P. Mosteiro, V. Muratova, L. Oberauer, M. Obolensky, F. Ortica, M. Pallavicini, L. Papp, C. Peña-Garay, L. Perasso, S. Perasso, A. Pocar, R. Raghavan, G. Ranucci, A. Razeto, A. Re, A. Romani, A. Sabelnikov, R. Saldanha, C. Salvo, S. Schönert, H. Simgen, M. Skorokhvatov, O. Smirnov, A. Sotnikov, S. Sukhotin, Y. Suvorov, R. Tartaglia, G. Testera, D. Vignaud, R. Vogelaar, F. von Feilitzsch, J. Winter, M. Wojcik, A. Wright, M. Wurm, J. Xu, O. Zaimidoroga, S. Zavatarelli, G. Zuzel. Precision Measurement of the 7Be Solar Neutrino Interaction Rate in Borexino. Physical Review Letters, 2011; 107 (14) DOI: 10.1103/PhysRevLett.107.141302

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

Measuring elusive solar neutrinos flowing through the Earth, physicists learn more about the sun

ScienceDaily (Oct. 11, 2011) — Using one of the most sensitive neutrino detectors on the planet, an international team including physicists Laura Cadonati and Andrea Pocar at the University of Massachusetts Amherst are now measuring the flow of solar neutrinos reaching earth more precisely than ever before. The detector probes matter at the most fundamental level and provides a powerful tool for directly observing the sun's composition.

Pocar, Cadonati and colleagues report in the current issue of Physical Review Letters that the Borexino instrument has now measured with high precision the flux of the beryllium seven (7Be) solar neutrino, abundant, low-energy particles once below the observable threshold. With this advance, they can now precisely study the behavior of solar neutrinos with kinetic energy below 1 megaelectron volt (MeV). Borexino scientists also recently reported the first observation of neutrinos produced in a little-studied solar nuclear process known as proton-electron-proton, or pep, and set of stringent limit on reactions involving carbon, nitrogen and oxygen (the CNO cycle) in the sun.

Cadonati says, "Borexino is the only detector capable of observing the entire spectrum of solar neutrinos at once. Our results, the culmination of 20 years of research, greatly narrow the observation precision. The data confirm the neutrino oscillations, flavor changes and flow predicted by models of the sun and particle physics."

Of particular interest, Pocar and Cadonati note, is the Borexino instrument's ability to more thoroughly test neutrino oscillation parameters, allowing an exploration of their characteristic non-zero mass, which does not fit the Standard Model of particle physics. "Our data can tell us about fundamental micro physics at the particle level," says Cadonati. "Borexino is using neutrinos to explore the interior of the sun, looking for new, exciting clues to the mysteries of the universe we cannot see." Pocar adds, "Our detector provides stringent tests of the three-neutrino oscillations model."

Solar neutrinos are produced in nuclear processes and radioactive decays of several elements during fusion reactions at the sun's core. As many as 65 billion of them stream out of the sun and hit every square centimeter of Earth's surface [or 420 billion every square inch] every second. But because they only interact through the nuclear weak force they pass through matter unaffected, making them very difficult to detect and to distinguish from the trace nuclear decays of ordinary materials. The weak force is one of the four fundamental forces of nature, with gravity, electromagnetism and the strong force. It is responsible for the radioactive decay of unstable subatomic particles, with a short range of influence, about 1 percent of the diameter of a typical atomic nucleus.

The Borexino instrument, housed far beneath Italy's Apennine Mountains, detects neutrinos as they interact with an ultra-pure organic liquid scintillator at the center of a large sphere surrounded by 2,000 tons of water. Its great depth and many onion-like protective layers maintain the core as the most radiation-free medium on the planet.

There are three neutrino types, or "flavors": electron, muon and tau. Those produced in the sun are the electron type. As they travel away from their birthplace, they oscillate, or change from one flavor to another. A detector like Borexino can observe all three types in real time and measures each one's energy, but it cannot distinguish between them. It's more sensitive to the electron type so they are more likely to be seen.

The 7Be neutrino flux now being detected by Borexino is predicted by the standard solar model to make up about 10 percent of solar flow, Cadonati says. Earlier instruments in Canada and Japan designed to detect higher-energy neutrinos had already observed evidence of their flavor oscillations, probing 1/10,000 of the solar neutrino flux and their oscillations as they travel through solar matter. However, without data in the low-energy range as scanned by Borexino, physicists were not able to confirm the specific energy-dependent effect of solar neutrino oscillations. Borexino has now filled this gap and for the first time observed evidence of neutrino oscillation in vacuum, as they travel between the sun and Earth.

Pocar says that from the astrophysics angle, Borexino's ability to conduct "precision physics" experiments and collect a large number of observations, with concomitant higher statistical power, is yielding data that show how our sun works. As for the possibility of discovering a new kind of neutrino coming from the sun, which is allowed by some theoretical extensions to the Standard Model of particle physics, he adds, "You always have the hope of seeing surprises, some small deviation from the expectations. And this you can only have if your accuracy and precision are good enough to see very small variations."

In a companion paper, the Borexino team says their 7Be solar neutrino flux measurements show no flow differences between day and night. Some had hypothesized that one might exist because neutrinos pass through Earth's bulk at night. But Pocar says, "The traverse through the Earth seems not to change neutrinos' flavor."

In the future, the researchers hope to identify the origin of every neutrino type coming from the sun, particularly to assess the relative levels of carbon, nitrogen and oxygen there, to deepen understanding of how the sun evolved and how its workings are related to that of larger stars.

Borexino is an international collaboration funded by the U.S. National Science Foundation, the Italian National Institute for Nuclear Physics (INFN) which manages the Gran Sasso labs and similar organizations in Germany, Russia and Poland.

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Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Massachusetts at Amherst.

Journal Reference:

G. Bellini, J. Benziger, D. Bick, S. Bonetti, G. Bonfini, M. Buizza Avanzini, B. Caccianiga, L. Cadonati, F. Calaprice, C. Carraro, P. Cavalcante, A. Chavarria, D. D’Angelo, S. Davini, A. Derbin, A. Etenko, K. Fomenko, D. Franco, C. Galbiati, S. Gazzana, C. Ghiano, M. Giammarchi, M. Goeger-Neff, A. Goretti, L. Grandi, E. Guardincerri, S. Hardy, Aldo Ianni, Andrea Ianni, V. Kobychev, D. Korablev, G. Korga, Y. Koshio, D. Kryn, M. Laubenstein, T. Lewke, E. Litvinovich, B. Loer, F. Lombardi, P. Lombardi, L. Ludhova, I. Machulin, S. Manecki, W. Maneschg, G. Manuzio, Q. Meindl, E. Meroni, L. Miramonti, M. Misiaszek, D. Montanari, P. Mosteiro, V. Muratova, L. Oberauer, M. Obolensky, F. Ortica, M. Pallavicini, L. Papp, C. Peña-Garay, L. Perasso, S. Perasso, A. Pocar, R. Raghavan, G. Ranucci, A. Razeto, A. Re, A. Romani, A. Sabelnikov, R. Saldanha, C. Salvo, S. Schönert, H. Simgen, M. Skorokhvatov, O. Smirnov, A. Sotnikov, S. Sukhotin, Y. Suvorov, R. Tartaglia, G. Testera, D. Vignaud, R. Vogelaar, F. von Feilitzsch, J. Winter, M. Wojcik, A. Wright, M. Wurm, J. Xu, O. Zaimidoroga, S. Zavatarelli, G. Zuzel. Precision Measurement of the 7Be Solar Neutrino Interaction Rate in Borexino. Physical Review Letters, 2011; 107 (14) DOI: 10.1103/PhysRevLett.107.141302

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

Astrophysics and extinctions: News about planet-threatening events

ScienceDaily (Oct. 7, 2011) — Space is a violent place. If a star explodes or black holes collide anywhere in our part of the Milky Way, they'd give off colossal blasts of lethal gamma-rays, X-rays and cosmic rays and it's perfectly reasonable to expect Earth to be bathed in them. A new study of such events has yielded some new information about the potential effects of what are called "short-hard" interstellar radiation events.

Several studies in the past have demonstrated how longer high-energy radiation bursts, such as those caused by supernovae, and extreme solar flares can deplete stratospheric ozone, allowing the most powerful and damaging forms of ultraviolet radiation to penetrate to Earth's surface. The probability of an event intense enough to disrupt life on the land or in the oceans becomes large, if considered on geological timescales. So getting a handle on the rates and intensities of such events is important for efforts to connect them to extinctions in the fossil record.

"We find that a kind of gamma ray burst -- a short gamma ray burst -- is probably more significant than a longer gamma ray burst," said astrophysicist Brian Thomas of Washburn University. Improved and accumulated data collected by the SWIFT satellite, which catches gamma ray bursts in action in other galaxies, is providing a better case for the power and threat of the short bursts to life on Earth.

The shorter bursts are really short: less than one second long. They are thought to be caused by the collision of two neutron stars or maybe even colliding black holes. No one is certain which. What is clear is that they are incredibly powerful events.

"The duration is not as important as the amount of radiation," said Thomas. If such a burst were to happen inside the Milky Way, it its effects would be much longer lasting to Earth's surface and oceans.

"What I focused on was the longer term effects," said Thomas. The first effect is to deplete the ozone layer by knocking free oxygen and nitrogen atoms so they can recombine into ozone-destroying nitrous oxides. These long-lived molecules keep destroying ozone until they rain out. "So we see a big impact on the ozone layer."

Those effects are likely to have been devastating for many forms of life on the surface -- including terrestrial and marine plants which are the foundation of the food web.

Based on what is seen among other galaxies, these short bursts, it seems that they occur in any given galaxy at a rate of about once per 100 million years. If that is correct, then it's very likely that Earth has been exposed to such events scores of times over its history. The question is whether they left a calling card in the sky or Earth's geological record.

Astronomical evidence is not likely, said Thomas, because the galaxy spins and mixes pretty thoroughly every million years, so any remnants of blasts are probably long gone from view. There might, however, be evidence in the ground here on Earth, he said. Some researchers are looking at the isotope iron-60, for instance, which has been argued as a possible proxy for radiation events.

If isotopes like iron-60 can reveal the strata of the events, it then becomes a matter of looking for extinction events that correlate and seeing what died and what survived -- which could shed more light on the event itself.

"I work with some paleontologists and we try to look for correlations with extinctions, but they are skeptical," said Thomas. "So if you go and give a talk to paleontologists, they are not quite into it. But to astrophysicists, it seems pretty plausible."

Thomas will be presenting his work on October 9, 2011, at the annual meeting of the Geological Society of America in Minneapolis. This work was supported by the NASA Astrobiology: Exobiology and Evolutionary Biology Program.

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Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

Finding answers century-old questions about platinum's catalytic properties

ScienceDaily (June 8, 2011) — Researchers now understand more about why platinum is so efficient at producing power in hydrogen fuel cells.

"Understanding platinum's properties for speeding up chemical reactions will potentially enable scientists to create significantly cheaper synthetic or metal alloy alternatives for use in sustainable devices like fuel cells," says Gregory Jerkiewicz, a professor in the Department of Chemistry who led the groundbreaking study, published in the journal Langmuir.

Dr. Jerkiewicz's research team has found that when platinum is used in reactions involving hydrogen it develops an embedded layer of hydrogen just one atom thick. This gives the platinum hydrophobic or water-repelling qualities, meaning that stray water molecules inside the fuel cell cannot bond strongly with the surface of the platinum.

The water-repelling nature of the modified platinum means that incoming hydrogen molecules can easily attach to the surface of the platinum and separate into smaller particles without requiring additional energy to displace any water molecules that are in the way.

The reduction in the energy required for hydrogen molecules to attach to the surface of the platinum means that the process is fast and efficient and the fuel cell can deliver a lot of power.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Queen's University.

Journal Reference:

Gregory Jerkiewicz, Gholamreza Vatankhah, Shin-ichi Tanaka, Jean Lessard. Discovery of the Potential of Minimum Mass for Platinum Electrodes. Langmuir, 2011; 27 (7): 4220 DOI: 10.1021/la200153n

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Atomic Gardens, the Biotechnology of the Past, Can Teach Lessons About the Future of Farming

When radioactive tomatoes were the crop of the future
Atomic Seeds Life Magazine via Pruned

One look at the wedge-shaped rows of plants and anyone could tell the circular garden was not grown under normal conditions. Plants sown in concentric circles displayed wildly different vitality and viability.

The innermost circle of plants, gathered around a central pole, were dead; slightly farther away, the plants were stunted and tumor-ridden; and past that, the plants may have looked right, but possessed strange new mutations.

It was the latter part of the archetypal “gamma garden” that most interested plant researchers in the 1950s and 1960s. The central pole contained a radioactive source, commonly cobalt-60, so that scientists could see how the gamma rays affected plants.

Before scientists learned how to modify genes, they induced mutations with radiation. It was a sincere effort to feed the world, and amaze home gardeners, by modifying plants to have desirable traits.

Nanotechnologist Paige Johnson shares the history of atomic gardening on her blog, Garden History Girl. Writer Alexander Trevi interviewed Johnson for his own blog, Pruned.

“If we think of modern GM as taking a scalpel to the genome, mutation breeding by irradiation was a hammer,” she says. The full interview is well worth a read; click through to it here.

It’s an interesting tale in light of radiation and food safety concerns after the Japanese nuclear disaster. But there are also some interesting parallels between atomic gardening and 21st-century biotechnology, which also promises to feed the world by modifying plants to have new traits. The promises, and the controversies, feel very familiar.

Back in the 1960s, scientists bombarded plants with gamma radiation hoping to see beneficial changes in the plants’ structure and yield. Advocates included entrepreneur C.J. Speas and Englishwoman Muriel Howorth, who started the Atomic Gardening Society to promote mutated varieties. Johnson describes a dinner party in which Howorth served “NC 4x,” North Carolina 4th generation X-rayed peanuts that were produced from seeds exposed to 18,500 roentgen units of X-rays. After the party, Howorth planted the irradiated seeds and they grew like magic beanstalks.

Journalists and sightseers came to visit the mutant plant; garden writer Beverley Nichols called the peanut the “most sensational plant in Britain.”

“To me it had all the romance of something from outer space. It is the first ‘atomic’ peanut. It is a lush, green plant and gives you a strange, almost alarming sense of thrusting power and lusty health. It holds a glittering promise in its green leaves, the promise of victory over famine,” she wrote, as recounted on Johnson’s blog.

As with modern biotechnology, industry was the main driver behind the new plant modifications. Two modern cultivars are the result of atomic gardening, Johnson says — most of the world's mint oil, used in toothpaste, chewing gum and more, comes from the “Todd's Mitcham” peppermint cultivar, which is resistant to a fungus. It was produced in radiation gardens at Brookhaven National Laboratory. And the “Rio Star” grapefruit varietal, which Johnson says accounts for three-fourths of grapefruit production in Texas, is another atomic mutant bred for its dark red flesh and juice.

Gamma garden research was conducted in the U.S., Sweden, India and other countries in the 1960s, leading to untold numbers of new plant varieties. But s far as Johnson can tell, the entrepreneur Speas was the only source for home gardeners to buy irradiated seeds. Seed packets depicted robust flowers and vegetables, calling them “atomic-energized” and offering an interesting definition of what radiation does — “gamma rays tend to shake up the normal balanced system of the embryo inside the plant.”

Atomic Energized Poppy: The seed packet advises gardeners that it may take more than a year for mutations to manifest themselves, and therefore not to destroy stunted plants: “The stunted plants may contain desirable changes when they again regain their hereditary balance in subsequent generations.”  Paige Johnson via Pruned

Eventually, as scientists and the public grew to understand the dangers posed by radiation exposure, gamma gardens fell out of favor. The notion of irradiated plants feeding a hungry world soon wilted, too.

Decades later, scientists would figure out how to make much more precise mutations, inserting new genes and switching them on to make plants do things they couldn’t do before. But this method has its own detractors, some of whom would argue genetic modification is just as bad for health and the environment as radioactivity research.

We know much more about biology today than we did in the 1960s. But will future generations look back on genetic modification like we reflect on atomic gardens, with an amused sense of nostalgia illuminated by hindsight?

View the original article here