Tag Archives: neutrons

Bold Move Forward in Molecular Analyses

By Guest PostMay 21, 2013Scienceabsolute scale, berkeley lab, cell biology, concentration, control, data collection, dataset, john tainer, macromolecules, molecular analyses, molecular machines, nanoparticle, neutrons, protein, robert rambo, sans, sas, sas analysis, sas based statistic, saxs, small angle scattering, solution, structural state, volume of correlation

Berkeley Lab Researchers Develop New Metrics for X-ray and Neutron Analysis of Flexible Macromolecules

A dramatic leap forward in the ability of scientists to study the structural states of macromolecules such as proteins and nanoparticles in solution has been achieved by a pair of researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab). The researchers have developed a new set of metrics for analyzing data acquired via small angle scattering (SAS) experiments with X-rays (SAXS) or neutrons (SANS). Among other advantages, this will reduce the time required to collect data by up to 20 times.

“SAS is the only technique that provides a complete snapshot of the thermodynamic state of macromolecules in a single image,” says Robert Rambo, a scientist with Berkeley Lab’s Physical Biosciences Division, who developed the new SAS metrics along with John Tainer of Berkeley Lab’s Life Sciences Division and the Scripps Research Institute. (more…)

New dark matter detector begins search for invisible particles

By Guest PostMay 12, 2013Sciencecanada, cf3i, chicagoland observatory, coupp, coupp 60, dark matter detector, dark matter experiment, dark matter particles, earth from space, fermilab, fire extinguishers, galaxies, hugh lippincott, ingredient, invisible particles, juan collar, massive particles, neutrons, ontario, purified water, rotational velocities, snolab, telescopes, underground particle physics, universe, university of chicago

Scientists heard their first pops last week in an experiment that searches for signs of dark matter in the form of tiny bubbles.

They will need to analyze them further in order to discern whether dark matter caused any of the COUPP-60 experiment’s first bubbles at the SNOLAB underground science laboratory in Ontario, Canada. Dark matter accounts for nearly 90 percent of all matter in the universe, yet it is invisible to telescopes.

“Our goal is to make the most sensitive detector to see signals of particles that we don’t understand,” said Hugh Lippincott, a postdoctoral scientist with Fermi National Accelerator Laboratory. Lippincott has spent much of the past several months leading the installation of the one-of-a-kind detector at SNOLAB, 1.5 miles underground. (more…)

Researchers Propose New Way to Probe Earth’s Deep Interior

By Guest PostFebruary 25, 2013Scienceafu lin, amherst college, atoms, austin, building blocks, central core, characteristics, characteristics of mantle, chemical properties, composition, deep earth, earth, earth rotation axis, electromagnetism, electron spin density, electrons, elusive fifth force, fifth force, geoelectrons, geological layer, geomagnetic field, gravitational attraction, gravity, interior, jung fu, larry hunter, magnetic interaction, mantle, Nature, neutrons, new technique, outer crust, protons, researchers, spin, spin directions, spin spin interaction, strong nuclear forces, subatomic particles, university of texas

AUSTIN, Texas — Researchers from Amherst College and The University of Texas at Austin have described a new technique that might one day reveal in higher detail than ever before the composition and characteristics of the deep Earth.

There’s just one catch: The technique relies on a fifth force of nature (in addition to gravity, the weak and strong nuclear forces and electromagnetism) that has not yet been detected, but which some particle physicists think might exist. Physicists call this type of force a long-range spin-spin interaction. If it does exist, this exotic new force would connect matter at Earth’s surface with matter hundreds or even thousands of kilometers below, deep in Earth’s mantle. In other words, the building blocks of atoms—electrons, protons, and neutrons—separated over vast distances would “feel” each other’s presence. The way these particles interact could provide new information about the composition and characteristics of the mantle, which is poorly understood because of its inaccessibility. (more…)

Bright Stars to Black Holes: UA Astronomer Awarded for Her Research

By Guest PostDecember 17, 2012Scienceabsorbs material, astronomy, astrophysical phenomena, black holes, cloud, collapsed stars, collision, dense remnants, energetic, feryal ozel, Galaxy, hydrogen gas, mass, nasa hubble fellow, neutron stars, neutrons, radiation, radio astronomers, radio telescopes, subatomic particles, sun, super, university of arizona

In addition to being selected as one of 50 scholars awarded fellowships each year at the prestigious Radcliffe Institute at Harvard University, the UA’s Feryal Ozel has won the 2013 American Physical Society’s Maria Goeppert Mayer Award for her cutting-edge research on neutron stars.

Feryal Ozel studies two things most people don’t think about everyday: neutron stars and black holes.

An associate professor of astronomy at the University of Arizona, Ozel has won the 2013 American Physical Society’s Maria Goeppert Mayer Award for her work on neutron stars and her dedication to public outreach and education in science and astronomy. In addition, this year she is completing a prestigious fellowship at the Radcliffe Institute at Harvard University. Ozel came to the UA in 2003 as a NASA Hubble fellow and began a faculty position in 2005. (more…)

Do We Live in a Computer Simulation? UW Researchers Say Idea Can be Tested

By Guest PostDecember 12, 2012Scienceatom, belief, binds subatomic particles, british philosopher, computer model, computer simulation, concept, cosmic rays, evolutionary history, four dimensional grid, fundamental forces, gluons, human species, lattice quantum chromodynamics, martin savage, model, molecule, Nature, neutrons, nick bostrom, notion, nucleus, parallel universe, physical laws, posthuman civilization, posthuman stage, potential test, primitive simulations, protons, quarks, scale, silas beane, small scale simulations, space time continuum, supercomputers, technique, universe, university of oxford, university of washington, zohreh davoudi

A decade ago, a British philosopher put forth the notion that the universe we live in might in fact be a computer simulation run by our descendants. While that seems far-fetched, perhaps even incomprehensible, a team of physicists at the University of Washington has come up with a potential test to see if the idea holds water.

The concept that current humanity could possibly be living in a computer simulation comes from a 2003 paper published in Philosophical Quarterly by Nick Bostrom, a philosophy professor at the University of Oxford. In the paper, he argued that at least one of three possibilities is true:

The human species is likely to go extinct before reaching a “posthuman” stage.
Any posthuman civilization is very unlikely to run a significant number of simulations of its evolutionary history.
We are almost certainly living in a computer simulation. (more…)

Researchers Reveal Structure of Carbon’s ‘Hoyle State’

By Guest PostDecember 11, 2012Sciencealpha clusters, alpha particles, bent arm, carbon 12, dean lee, element, evgeny epelbaum, german colleague, helium 4 nuclei, hermann krebs, hoyle state, lattice, life on earth, neutrons, north Carolina, nucleons, particle, physicist, picture, protons, simulate, snapshot, state university, structure, timo laehde, ulf g meissner

A North Carolina State University researcher has taken a “snapshot” of the way particles combine to form carbon-12, the element that makes all life on Earth possible. And the picture looks like a bent arm.

Carbon-12 can only exist when three alpha particles, or helium-4 nuclei, combine in a very specific way. This combination is known as the Hoyle state. NC State physicist Dean Lee and German colleagues Evgeny Epelbaum, Hermann Krebs and Ulf-G. Meissner had previously confirmed the existence of the Hoyle state using a numerical lattice that allowed the researchers to simulate how the protons and neutrons interact. When the researchers ran their simulations on the lattice, the Hoyle state appeared together with other observed states of carbon-12, proving the theory correct from first principles. (more…)

Saber-toothed Cats and Bear Dogs: How They Made Cohabitation Work

By Guest PostNovember 8, 2012Scienceanalysis, batallones, bear dog, carbon 12, carbon isotope, cat species, catherine badgley, cats, cerro, de, extinct mammals, food web, fossilized fangs, geological pits, habitat, history, late, los, machairodus aphanistus, madrid, mammalian predator, michigan, miocene, miocene period, neutrons, nucleus, palaeontologist, promegantereon ogygia, ratio, saber toothed, soledad domingo, stable, tooth enamel, u m museum, university, woodland area

ANN ARBOR — The fossilized fangs of saber-toothed cats hold clues to how the extinct mammals shared space and food with other large predators 9 million years ago.

Led by the University of Michigan and the Museo Nacional de Ciencias Naturales in Madrid, a team of paleontologists has analyzed the tooth enamel of two species of saber-toothed cats and a bear dog unearthed in geological pits near Madrid. Bear dogs, also extinct, had dog-like teeth and a bear-like body and gait. (more…)

Homing in on Higgs: Michigan Researchers Predict Summer Discovery

By Guest PostJune 4, 2012Scienceaaron armbruster, algorithms, atlas, atoms, bing zhou, CERN, Chicago, electromagnetic radiation, electrons, fermilab, forces, function, geneva, gordon kane, higgs, higgs boson, higgs field particles, homer neal, jianming qian, junjie zhu, Large Hadron Collider, laws, laws of nature, lhc, missing piece, Nature, neutrons, newton, particle physics, physics theory, protons, quarks, rudolf thun, standard model, stephen hawking, summer, switzerland, tevatron particle accelerator, university of michigan, vacuum like state

ANN ARBOR, Mich.— Whether the Higgs boson exists could be settled by the end of summer, say University of Michigan physicists involved in the search for the missing piece of particle physics’ Standard Model.

“We’re zooming in,” said Jianming Qian, physics professor in the College of Literature, Science & the Arts. “We are increasing the data set and improving our search algorithms. With certain luck, we may be able to discover it this summer, but it depends on nature.”

Qian is one of the 28 U-M researchers involved in experiments at CERN’s Large Hadron Collider (LHC) in Switzerland. He’ll spend most of his time through August in Geneva, where more than 1,000 scientists from around the world have been looking for Higgs since the collider turned on about four years ago. (more…)