Slashdot Mirror

mdsolar sends this report from Symmetry Magazine: Cosmic rays can help scientists do something no one else can: safely image the interior of the nuclear reactors at the Fukushima Daiichi plant. ... [M]uon tomography is similar to taking an X-ray, only it uses naturally produced muons. These particles don't damage the imaged materials and, because they already stream through everything on Earth, they can be used to image even the most sensitive objects. Better yet, a huge amount of shielding is needed to stop muons from passing through an object, making it nearly impossible to hide from muon tomography. ... By determining how muons scatter as they interact with electrons and nuclei within the item, the team's software creates a three-dimensional picture of what's inside. ... To prove the technology, the Los Alamos team shipped a demo detector system to a small, working nuclear reactor in a Toshiba facility in Kawasaki, Japan. There, they placed one detector on either side of the reactor core. "When we analyzed our data we discovered that in addition to the fuel in the reactor core, they had put a few fuel bundles off to the side that we didn't know about," says Morris. "They were really impressed that not only could we image the core, but that we also found those bundles."

Graculus writes: The Department of Energy and the National Science Foundation announced on Friday that they will try to fund two major experiments to detect particles of the mysterious dark matter whose gravity binds the galaxies instead of just one. The decision allays fears that the funding agencies could afford only one experiment to continue the search for so-called weakly interacting massive particles, or WIMPs.

Hugh Pickens DOT Com writes "Amanda Solliday reports at Symmetry that six months ago, organizers of a biweekly forum on Large Hadron Collider physics at Fermilab banned PowerPoint presentations in favor of old-fashioned, chalkboard-style talks. 'Without slides, the participants go further off-script, with more interaction and curiosity,' says Andrew Askew. 'We wanted to draw out the importance of the audience.' In one recent meeting, physics professor John Paul Chou of Rutgers University presented to a full room holding a single page of handwritten notes and a marker. The talk became more dialogue than monologue as members of the audience, freed from their usual need to follow a series of information-stuffed slides flying by at top speed, managed to interrupt with questions and comments. Elliot Hughes, a Rutgers University doctoral student and a participant in the forum, says the ban on slides has encouraged the physicists to connect with their audience. 'Frequently, in physics, presenters design slides for people who didn't even listen to the talk in the first place,' says Hughes. 'In my experience, the best talks could not possibly be fully understood without the speaker.'"

eldavojohn writes "Scientists at Fermilab have decided that it's high time they build a 'holometer' to test the smoothness of space-time. Theoretical physicists like Stephen Hawking have proposed that space-time is not smooth but it's been a lot of math and no actual data. The Fermilab team plans to build two relatively small devices that act as 'holographic interferometers' to measure the shaking or vibration in split beams of light traveling through a vacuum. If the team finds the shaking in their measurements and records them, the theory of a holographic universe will have some evidence of non-smoothness in space-time and perhaps a foothold in bringing light to the heavily debated theoretical physics."

krou writes "Recent results from the Dzero experiment at the Tevatron particle accelerator suggest that those looking for a single Higgs boson particle should be looking for five particles, and the data gathered may point to new laws beyond the Standard Model. 'The DZero results showed much more significant "asymmetry" of matter and anti-matter — beyond what could be explained by the Standard Model. Bogdan Dobrescu, Adam Martin and Patrick J Fox from Fermilab say this large asymmetry effect can be accounted for by the existence of multiple Higgs bosons. They say the data point to five Higgs bosons with similar masses but different electric charges. Three would have a neutral charge and one each would have a negative and positive electric charge. This is known as the two-Higgs doublet model.'" There's more detail in this writeup from Symmetry Magazine, a joint publication of SLAC and Fermilab. Here's the paper on the arXiv.

An anonymous reader writes "At 1:06 p.m. Central European Summer Time (CEST) today, the first protons collided at 7 TeV in the Large Hadron Collider. These first collisions, recorded by the LHC experiments, mark the start of the LHC's research program."

PhysicsDavid writes "Announced this morning by Fermilab, the possible territory for the Higgs boson has shrunk even further. Combined results from the CDF and DZero experiments at the Tevatron have ruled out the existence of the Higgs with a mass between 160 and 170 GeV/c^2 with 95% confidence. At 90% confidence the Higgs is ruled out between about 157 and 185 GeV/c^2. Here is Fermilab's press release. If the Higgs is to be found at the lighter end of the currently allowed range of 114 GeV/c^2 to 185 GeV/c^2, its detection will be harder than at the heavier end due to the kinds of signals that the Large Hadron Collider and the Tevatron will see. Some physicists think that a lighter Higgs will be easier to spot at the Tevatron as the background processes which obscure the faint signal are not as prevalent in those experiments."

PhysicsDavid writes "Physicists have been searching for magnetic monopoles pretty much since they knew about magnetism and definitely since Maxwell unified electricity and magnetism. Now some researchers have shown that using some weird mirror materials will allow them to create something indistinguishable from a monopole in a lab experiment. A paper about it was published today in the journal Science as an advance online publication (abstract; full article available only to AAAS members). The technique looks like it could be used to create analog systems of other kinds of exotic particles that haven't yet been observed, such as axions. The theorists who proposed this are working with experimenters to try to create these systems and study them in depth this year."

Physicser writes "Want to read every single technical detail of the design and construction of the Large Hadron Collider and its six detectors? The whole shebang — seven reports totaling 1600 pages, 115 MB, with contributions from 8000 scientists and engineers — has been published electronically by the Journal of Instrumentation, free to read without a subscription."

PhysicsDavid writes "In a suite of new results about the Higgs boson, Fermilab presents the first new definitive evidence on the (lack of) existence of the Higgs boson since the Large Electron Positron collider shut down in 2000. Fermilab hasn't found the Higgs, but can rule out a certain range of masses for the particle that is believed to create mass for all the other particles of nature. Other Higgs news suggests a new likeliest mass range of 115 to 135 GeV for the Higgs. These results were among those presented at the ICHEP 2008 conference currently wrapping up in Philadelphia."

PhysicsDavid writes "In a suite of new results about the Higgs boson, Fermilab presents the first new definitive evidence on the (lack of) existence of the Higgs boson since the Large Electron Positron collider shut down in 2000. Fermilab hasn't found the Higgs, but can rule out a certain range of masses for the particle that is believed to create mass for all the other particles of nature. Other Higgs news suggests a new likeliest mass range of 115 to 135 GeV for the Higgs. These results were among those presented at the ICHEP 2008 conference currently wrapping up in Philadelphia."

PhysicsDavid writes "Collaborators on the BaBar experiment at the Stanford Linear Accelerator Center have detected and measured, for the first time after a 30-year search, the lowest energy particle of the 'bottomonium' family, called the eta-sub-b. Bottomonium consists of a bottom quark and an anti-bottom quark bound together by the strong force. The discovery fills in a missing piece of quark physics that will help reveal the nature and behavior of the quarks and the strong force."

PhysicsDavid writes "Collaborators on the BaBar experiment at the Stanford Linear Accelerator Center have detected and measured, for the first time after a 30-year search, the lowest energy particle of the 'bottomonium' family, called the eta-sub-b. Bottomonium consists of a bottom quark and an anti-bottom quark bound together by the strong force. The discovery fills in a missing piece of quark physics that will help reveal the nature and behavior of the quarks and the strong force."

atrocious cowpat passes along a call for help from symmetry magazine, the joint publication of Fermilab and SLAC, noting: "Could be just plain gibberish, it could be something like those wonderfully weird letters to the Mount Wilson observatory, or it could be a message from aliens who just happened to have gotten their hands (tentacles/exoskeleton) on a fax machine." "A little over a year ago, the Fermilab Office of Public Affairs received a curious letter in code (4.4-MB image here). It has been sitting in our files all that time and we haven't had much of a chance to look into breaking the code, nor are we particularly expert at this!"

atrocious cowpat passes along a call for help from symmetry magazine, the joint publication of Fermilab and SLAC, noting: "Could be just plain gibberish, it could be something like those wonderfully weird letters to the Mount Wilson observatory, or it could be a message from aliens who just happened to have gotten their hands (tentacles/exoskeleton) on a fax machine." "A little over a year ago, the Fermilab Office of Public Affairs received a curious letter in code (4.4-MB image here). It has been sitting in our files all that time and we haven't had much of a chance to look into breaking the code, nor are we particularly expert at this!"

David Harris, editor-in-chief at Symmetrymagazine.org (a joint publication of Fermilab and SLAC), sends us to his blog covering the American Physical Society meeting now going on in St. Louis. Among the breaking physics news relating to topics we have discussed in the past: results that explain about 1/3 of the Pioneer anomaly by differential heat flow in the spacecraft; an analysis of the Fermilab Tevatron's chances of spotting the Higgs "God particle"; and a hint that an Italian team has replicated their results from the year 2000 pointing to a detection of dark matter.

counterfriction writes "This month's issue of Symmetry, a magazine jointly published by SLAC and Fermilab, is featuring an article that points out the sometimes extemporaneous and unconventional solutions physicists have come up with in (and out of) the laboratory. From the article: 'Leon Lederman ... used a pocket knife, tape, and items on anyone's grocery list to confirm that interactions involving the weak force do now show perfect mirror symmetry, or parity, as scientists had long assumed.'"

PhysicsDavid writes to tell us about an article in Symmetry magazine. Jan-Henrik Anderson, a designer with a background in architecture, has collaborated with several particle physicists to develop visual representations of particles based on their physical characteristics. It is the closest most will ever get to 'seeing' a top quark.