Browsing All Posts filed under »NUCLEAR PHYSICS«

Plutonium signature captured after 50 years of trying

May 17, 2012

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by Jacob Aron Devoted fans can wait hours on the red carpet to get their favourite movie star’s autograph, but that’s nothing compared to acquiring the signature of plutonium-239. After 50 years of trying, physicists have finally managed to analyse the fissile isotope using nuclear magnetic resonance (NMR) spectroscopy. This could potentially allow them to… [Read more…]

Scientists propose a solution to a critical barrier to producing fusion

April 23, 2012

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By John Greenwald Physicists have discovered a possible solution to a mystery that has long baffled researchers working to harness fusion. If confirmed by experiment, the finding could help scientists eliminate a major impediment to the development of fusion as a clean and abundant source of energy for producing electric power. An in-depth analysis by… [Read more…]

New detector design improves gamma-ray measurements

April 6, 2012

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In the pursuit of precision measurements, nothing is simple, even when the apparatus employed appears to be utterly uncomplicated. An instructive case in point is the new ionization chamber used to determine the U.S. primary standard for radiation dose in air — or, strictly speaking, air kerma, the amount of kinetic energy released per unit… [Read more…]

Physicists discover evidence of rare hypernucleus

February 17, 2012

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…. a component of strange matter Physicists in Italy have discovered the first evidence of a rare nucleus that doesn’t exist in nature and lives for just 10-10 seconds before decaying. It’s a type of hypernucleus that, like all nuclei, contains an assortment of neutrons and protons. But unlike ordinary nuclei, hypernuclei also contain at… [Read more…]

Rutherford, Radioactivity, and the Atomic Nucleus

February 7, 2012

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Helge Kragh Modern atomic and nuclear physics took its start in the early part of the twentieth century, to a large extent based upon experimental investigations of radioactive phenomena. Foremost among the pioneers of the new kind of physics was Ernest Rutherford, who made fundamental contributions to the structure of matter for more than three… [Read more…]

Carbon Dating with Lasers

January 3, 2012

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Phys. Rev. Lett. 107, 270802 (2011) [4 pages] Molecular Gas Sensing Below Parts Per Trillion: Radiocarbon-Dioxide Optical Detection I. Galli, S. Bartalini, S. Borri, P. Cancio*, D. Mazzotti, P. De Natale, and G. Giusfredi Istituto Nazionale di Ottica-CNR (INO-CNR) and European Laboratory for Non-Linear Spectroscopy (LENS) Via N. Carrara 1, I-50019 Sesto Fiorentino, Italy Radiocarbon (14C) concentrations at a 43 parts-per-quadrillion… [Read more…]

‘Lethal’ radiation doses can be treated with drugs

December 4, 2011

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MICE can survive a dose of radiation that should have killed them when given a double-drug therapy – even if they get the drug cocktail 24 hours after exposure. Radiation damages rapidly dividing cells in the intestine, allowing harmful bacteria to leak into the bloodstream. Eva Guinan at Harvard Medical School found that boosting levels of a… [Read more…]

Unusual levels of radioactivity (iodine-131) in France

November 15, 2011

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Read also: Radioactivity in Europe (update17-11-2011) Selon l’Agence hongroise de l’énergie nucléaire, les très faibles concentrations d’iode 131 mesurées dans l’atmosphère de différents pays d’Europe, dont la France, proviennent d’un Institut spécialisé dans la production de produits radioactifs à usage médical ou industriel. L’AIEA qui vient de publier l’information rappelle que ces rejets ne présentent… [Read more…]

Radiation Measurements at the Campus of Fukushima Medical University

November 14, 2011

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….. through the 2011 off the Pacific Coast of Tohoku Earthquake and Subsequent Nuclear Power Plant crisis Tsuneo Kobayashi An earthquake, Tohoku region Pacific Coast earthquake, occurred on the 11th of March, 2011, and subsequent Fukushima nuclear power plant accidents have been stirring natural radiation around the author’s office in Fukushima Medical University (FMU). FMU… [Read more…]

On the interaction between two point electric charges

November 13, 2011

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Alexei M. Frolov The general formula for the interaction potential between two point electric charges is derived. This analytical formula has the correct asymtotic behaviour at large distances between two interacting charges. The derivation of this formula is based on the closed analytical expression for the Uehling potential obtained earlier (A.M. Frolov and D.M. Wardlaw,… [Read more…]

Radioactivity in Europe

November 12, 2011

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The UN atomic agency said Friday “very low levels” of radioactive iodine-131 had been detected in the air in the Czech Republic and in other countries, but presented no risk to human health. The Czech nuclear safety office said the source of the contamination was “most probably” outside the Czech Republic, and that its information… [Read more…]

Super-Powerful X-Ray Beam Will Probe the Center of the Earth

November 10, 2011

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It is much easier to get to Mars than to get deep inside this planet, so for all our knowledge about things like earthquakes and the magnetic field, Earth’s interior is actually very poorly understood. To study how metals interact at the prodigious pressures within, scientists squeeze small particles in the lab and heat them… [Read more…]

Marie Curie’s birth celebrated by Google doodle

November 7, 2011

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Search engine honours Nobel prize-winning scientist who was renowned for her pioneering work on radioactivity The birth of Nobel prize-winning scientist Marie Curie has being marked by Google with a picture of her at her work bench on the search engine’s home page. The Polish-born physicist and chemist is renowned for her pioneering work on… [Read more…]

Double Beta Decay

October 30, 2011

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Steven R. Elliott At least one neutrino has a mass of about 50 meV or larger. However, the absolute mass scale for the neutrino remains unknown. Furthermore, the critical question: Is the neutrino its own antiparticle? is unanswered. Studies of double beta decay offer hope for determining the absolute mass scale. In particular, zero-neutrino double… [Read more…]

Inside the fusion furnace of California’s star chamber

October 21, 2011

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Tiny stars are being created by the world’s largest and most energetic lasers in the hope of tapping what could be a relatively clean energy source – nuclear fusion. The National Ignition Facility at Lawrence Livermore National Laboratory in California is at the forefront of efforts to harness the power of fusion. It is also… [Read more…]

Oscillations in the decay law: a possible quantum mechanical explanation of the GSI anomaly?

October 12, 2011

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Francesco Giacosa, Giuseppe Pagliara We study the deviations from the usual exponential decay law for quantum mechanical systems. We show that simple and physically motivated deviations from the Breit-Wigner energy distribution of the unstable state are sufficient to generate peculiar deviations from the exponential decay law. Denoting with p(t) the survival probability, its derivative h(t)… [Read more…]

Time reversal: A simple particle could reveal new physics

October 11, 2011

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A simple atomic nucleus could reveal properties associated with the mysterious phenomenon known as time reversal and lead to an explanation for one of the greatest mysteries of physics: the imbalance of matter and antimatter in the universe. The physics world was rocked recently by the news that a class of subatomic particles known as… [Read more…]

Stellar Nucleosynthesis Nuclear Data Mining

October 6, 2011

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Boris Pritychenko Stellar nucleosynthesis is an important nuclear physics phenomenon that is responsible for presently observed chemical elements and isotope abundances. It is also one of the corner stone hypotheses that provides basis for our understanding of Nature. Its theoretical predictions are often verified through the astrophysical observation and comparison of calculated isotopic abundances with… [Read more…]

UK joins laser nuclear fusion project

September 9, 2011

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By Jason Palmer The UK has formally joined forces with a US laser lab in a bid to develop clean energy from nuclear fusion. Unlike fission plants, the process uses lasers to compress atomic nuclei until they join, releasing energy. The National Ignition Facility (Nif) in the US is drawing closer to producing a surplus… [Read more…]

Νuclear cars

September 7, 2011

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Thorium lasers: The thoroughly plausible idea for nuclear cars Some proposed technological innovations seem so far out that they are easy to reject out of hand. But sometimes, a new idea has a kernel of plausibility. Such is the case with a new project to develop a thorium laser power generation system that its creator… [Read more…]

Teaching Radioactivity: Ions produced by radiation carry a current

August 31, 2011

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This demonstartes that a radioactive source produces radiation that will ionise the air. The conducting air completes a circuit to charge an electroscope. Use the circuit to show the ionising effect of the radiation and present it as a means of detecting ionising radiation.

Samuel A. Goudsmit Papers available online

August 20, 2011

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The Niels Bohr Library and Archives is pleased to announce that it has digitized the complete Samuel A. Goudsmit Papers (1921–1979, 30 linear feet, approximately 67,000 images). The Goudsmit Papers are a major international collection of correspondence, research notebooks, reports, World War II science documents, and other material of Goudsmit, a Dutch physicist who spent most of… [Read more…]

Fukushima Radiation In California

August 17, 2011

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We all remember the earthquake and ensuing tsunami that hit Japan (see figure 1) and caused major troubles in the Fukushima nuclear power plant, which was severely damaged. Problems with containing radiation followed, leading to the pumping of huge amounts of seawater into the reactor, in an attempt to cool it down. The question on… [Read more…]

Star power: Small fusion start-ups aim for break-even

August 16, 2011

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Nuclear fusion will cost a fortune – or will it? A new wave of upstart companies think they’ve found cheaper, quicker ways to build a second sun A VAST earth platform looms into view above the treetops of Cadarache in France’s sultry south-east. It measures 1 kilometre long by 400 metres wide, and excavators dotted… [Read more…]

Neutrons Become Cubes Inside Neutron Stars

August 11, 2011

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Intense pressure can force neutrons into cubes rather than spheres, say physicists Inside atomic nuclei, protons and neutrons fill space with a packing density of 0.74, meaning that only 26 percent of the volume of the nucleus in is empty. That’s pretty efficient packing. Neutrons achieve a similar density inside neutron stars, where the force… [Read more…]

100-year-old model of the atom to be celebrated

August 5, 2011

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A series of public lectures taking place next week will look at the legacy of Rutherford’s discovery and give citizens of Manchester the chance to join nuclear physicists from around the world in celebrating his 100-year-old model of the atom. The lectures will explain how fundamental physics has moved on from Rutherford’s discovery to the… [Read more…]

Antiproton Radiation Belt Discovered Around Earth

August 4, 2011

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Physicists have long suspected that antiprotons must become trapped in a belt around Earth. Now they’ve found it The Earth is constantly bombarded by high energy particles called cosmic rays. These are generated by the Sun and by other sources further afield. (The source of the highest energy cosmic rays is still a mystery). The… [Read more…]

Antiprotons pass latest symmetry test

July 28, 2011

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By Hamish Johnston For something that is rare in the universe, antimatter has certainly been in the news a lot lately. The latest breakthrough involves antiprotonic helium and is published in Nature today. This exotic “atom” is formed when one electron in a helium atom is replaced with an antiproton, which is negatively charged. For two decades… [Read more…]

New laser technique makes cold positronium

July 25, 2011

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Physicists in the US have shown that positronium – a short-lived bound state of a positron and an electron – can be produced by firing a laser beam onto a silicon surface. Because the technique is highly controllable and operates over a wide range of temperatures, it could prove extremely useful in low-temperature experiments designed… [Read more…]

Inside the Innards of a Nuclear Reactor: Tiny Robots May Monitor Underground Pipes for Radioactive Leaks

July 23, 2011

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As workers continue to grapple with the damaged Fukushima Daiichi nuclear powerplant in Japan, the crisis has shone a spotlight on nuclear reactors around the world. In June, The Associated Press released results from a yearlong investigation, revealing evidence of “unrelenting wear” in many of the oldest-running facilities in the United States. That study found… [Read more…]

Best ever measurement of Earth’s radioactivity

July 19, 2011

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Ghostly subatomic particles streaming from Earth’s interior have enabled the most precise measurement yet of our planet’s radioactivity. These particles, called antineutrinos, suggest that about half of Earth’s heat comes from the radioactive decay of uranium and thorium – and give clues to the location of geological stashes of these elements. Heat is needed to… [Read more…]

Quantum quirk makes carbon dating possible

July 15, 2011

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RADIOCARBON dating relies on carbon-14 to decode an object’s age, but the isotope has steadfastly refused to divulge the key to its own unusual longevity. The answer, it seems, lies in the bizarre rules of quantum physics. Carbon-14 decays with a half-life of 5730 years, so it is often used to date objects up to about 50,000… [Read more…]

My favourite particle: the neutron

July 15, 2011

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A guest post by Jim Grozier on particles you can store in a beryllium bottle without a lid on I’m not really one for favourites, but I do have a soft spot for the neutron; and after all, it would be a shame to leave it out, wouldn’t it? There are two things I really… [Read more…]

Periodic Table gets new elements (but no one knows what they do)

June 8, 2011

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They have existed for less than a second each, but two new elements have been added to the Periodic Table Evidence for the existence of the two elements, the heaviest yet to be included, has been mounting for several years. A number of research teams had claimed to have produced the heavy elements by smashing… [Read more…]

Antimatter in a bottle: Scientists stabilise the staple of science fiction disasters for 16 whole minutes

June 6, 2011

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Scientists have successfully stored anti-matter – the mysterious substance used as a weapon of mass destruction in the novels of Da Vinci Code author Dan Brown. Researchers at CERN, home of the Large Hadron Collider, had bottled antimatter back in 2010, keeping hold of the atoms for a fraction of a second. But CERN have now… [Read more…]

New Synchrotron Technique Could See Hidden Building Blocks of Life

May 30, 2011

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Scientists from Finland and France have developed a new synchrotron X-ray technique that may revolutionize the chemical analysis of rare materials like meteoric rock samples or fossils. The results have been published on 29 May 2011 in Nature Materials as an advance online publication Life, as we know it, is based on the chemistry of… [Read more…]

NMR spectroscopy without the ‘M’

May 29, 2011

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Nuclear magnetic resonance (NMR) spectroscopy is perhaps the most useful technique in the organic chemist’s toolkit. But conventional NMR requires the sample to be placed in a very high magnetic field, which needs large and expensive superconducting magnets cooled by liquid helium. Now, an interdisciplinary group in the US has managed to accomplish NMR spectroscopy… [Read more…]

Chain Reactions Reignited At Fukushima After Tsunami

May 9, 2011

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Radioactive byproducts indicate that nuclear chain reactions must have been burning at the damaged nuclear reactors long after the disaster unfolded Nuclear reactors produce radioactive by-products that decay at different rates. One common by-product is iodine-131 which has a half life of about 8 days while another is cesium-137 with a half life of about… [Read more…]

Inside Japanese nuclear plant

May 4, 2011

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