Physics

Researchers at the National Institute of Standards and Technology (NIST) and the University of Maryland have developed a new optical method that can detect individual neutrons and record them over a range of intensities at least a hundred times greater than existing detectors. The new detector, described at the March Meeting of the American Physical Society by Charles Clark, a Fellow of the Joint Quantum Institute of NIST and the University of Maryland, promises to improve existing neutron measurements and enable tests of new phenomena beyond the Standard Model, the basic framework of…

Radio waves accelerate electrons within Jupiter’s magnetic field in the same way as they do on Earth, according to new research. The discovery overturns a theory that has held sway for more than a generation and has important implications for protecting Earth-orbiting satellites. Using data collected at Jupiter by the Galileo spacecraft, Dr Richard Horne of British Antarctic Survey (BAS) and colleagues from the University of California, Los Angeles, and the University of Iowa found that a special type of very low frequency radio wave is strong enough to accelerate electrons up to very high…

This week, NASA's Wilkinson Microwave Anisotropy Probe (WMAP) showed off three key findings contained in five years of data: (1)New evidence that a sea of cosmic neutrinos permeates the universe (2) Clear evidence the first stars took more than a half-billion years to create a cosmic fog (3)Tight new constraints on the burst of expansion in the universe's first trillionth of a second "We are living in an extraordinary time," said Gary Hinshaw of NASA's Goddard Space Flight Center in Greenbelt, Md. "Ours is the first generation in human history to make such detailed and far-reaching…

Stopping and cooling most of the atoms of the periodic table is now possible using a pair of techniques developed by physicist Mark Raizen at The University of Texas at Austin. Raizen stopped atoms by passing a supersonic beam through an “atomic coilgun” and cooled them using “single-photon cooling.” The techniques are a major step forward in atomic physics and have a variety of scientific and technological applications. They could be used to determine the mass of the neutrino, which is the primary candidate for dark matter. “Our methods open up whole new avenues of research,” says Raizen,…

An atomic clock that uses an aluminum atom to apply the logic of computers to the peculiarities of the quantum world now rivals the world's most accurate clock, based on a single mercury atom. Both clocks are at least 10 times more accurate than the current U.S. time standard. The measurements were made in a yearlong comparison of the two next-generation clocks, both designed and built at the Commerce Department's National Institute of Standards and Technology (NIST). The clocks were compared with record precision, allowing scientists to measure the relative frequencies of the two clocks to…

People who handle explosives usually have heavy-duty tasks to perform – dislodging rocks, demolishing old buildings, or triggering an avalanche. Now explosives can be used for delicate tasks, too, like making it possible to place holograms in steel. Nearly everybody carries holograms around on light things, like money or tickets for a concert, because they protect against forgery. They take a great deal of effort to produce, and are almost impossible to copy, because the image is created not only by the interaction of different colors and contrasts, but also by the surface structure.…

According to quantum mechanics, small magnetic objects called nanomagnets can exist in two distinct states (i.e. north pole up and north pole down). They can switch their state through a phenomenon called quantum tunneling. When the nanomagnet switches its poles, the abrupt change in its magnetization can be observed with low-temperature magnetometry techniques used in del Barco’s lab. The switch is called quantum tunneling because it looks like a funnel cloud tunneling from one pole to another. A new paper in Nature shows that two almost independent halves of a new magnetic molecule can…

How do scientists store nothing? It may sound like the beginning of a bad joke, but the answer is causing a stir in the realm of quantum physics after two research teams, including one from the University of Calgary, have independently proven it’s possible to store a special kind of vacuum in a puff of gas and then retrieve it a split second later. In our everyday life, light is completely gone when we turn it off. In the world of quantum physics, which governs microscopic particles, even the light that is turned off exhibits some noise. This noise brings about uncertainty that can cause…

Today the ATLAS collaboration at CERN celebrates the lowering of its last large detector element. The ATLAS detector is the world’s largest general-purpose particle detector, measuring 46 metres long, 25 metres high and 25 metres wide; it weighs 7000 tonnes and consists of 100 million sensors that measure particles produced in proton-proton collisions in CERN’s Large Hadron Collider(LHC). The first piece of ATLAS was installed in 2003 and since then many detector elements have journeyed down the 100 metre shaft into the ATLAS underground cavern. This last piece completes this gigantic puzzle…

Naval warships are all-powerful vessels but they are also easy to spot. Concerns about being detected have led the military to develop new stealth technologies that allow ships to be virtually invisible to the human eye, to dodge roaming radars, put heat-seeking missiles off the scent, disguise their own sound vibrations and even reduce the way they distort the Earth’s magnetic field, as senior lecture in remote sensing and sensors technology at Britannia Royal Navy College, Chris Lavers, explains in March’s Physics World. Wars throughout the twentieth century prompted advances in stealth…