Ultra-bright X-rays...

Overview: Advanced Photon Source, Argonne National Laboratory

Topics: High Energy Physics, Particle Physics, Theoretical Physics, X-rays

The upgrade of the U.S. Department of Energy’s Advanced Photon Source at Argonne National Laboratory will make it between 100 and 1,000 times brighter than it is today.

“That factor is such a big change, it’s going to revolutionize the types of science that we can do,” said Stephen Streiffer, Argonne Associate Laboratory Director for Photon Sciences and Director of the APS.

“We’ll be able to look at the structure of materials and chemical systems in the interior of things — inside a turbine blade or a catalytic reactor — almost down to the atomic scale. We haven’t been able to do that before. Given that vast change, we can only dream about the science we’re going to do.”

In December, DOE approved the technical scope, cost estimate and plan of work for an upgrade of APS.

The APS upgrade has been in the works since 2010. The upgrade will reveal a new machine that will allow its 5,500 annual users from university, industrial, and government laboratories to work at a higher spatial resolution, or to work faster with a brighter beam (a beam with more X-rays focused on a smaller spot) than they can now.

Beam Us Up: Ultra-bright X-ray beams expanding the boundaries of research
Steve Koppes, Argonne National Laboratory

Sudoku and Velocity Fields...

Image Source: Link below

Topics: Materials Science, Probability, Radiation, X-rays

To see what happens inside a pile of sand or another volume of granular material, researchers rely either on deformation observations at the surface, which don’t always reflect any internal flows, or on simulations. Several existing techniques can image interior flows, but they each have one or more disadvantages, such as limited spatial and temporal resolutions, high costs, and invasiveness. A new technique, developed by James Baker, Itai Einav, and their colleagues at the University of Sydney, overcame those hurdles by using sets of two-dimensional x-ray radiographs to uncover the three-dimensional velocity field inside a volume of opaque grains.

X rays were fired from three orthogonal locations through a container of opaque grains that were being sheared from below by a conveyor belt, as shown in the diagram above. By spatially correlating successive radiographs, the researchers extracted the probability density functions (PDFs) of the two displacement components orthogonal to the x-ray direction for each grid cell. Each PDF was then sampled evenly to generate an unsorted array of the different displacements through the beam direction.

By combining the PDF results orthogonal to each other and solving a Sudoku-style puzzle, the researchers were able to reconstruct the 3D velocity field shown from 2D projections. As in Sudoku, the displacement values that should be placed in each row and column are known from the two sets of PDFs, but how to arrange those displacements in space defines the puzzle. Unlike in Sudoku, though, there is no unique solution.

X-ray correlations assemble a complete velocity field, Alex Lopatka, Physics Today

Fallback Disk...

A group of researchers recently observed a mysterious infrared emission coming from near a pulsar in NASA's Hubble Space telescope data. This animation depicts one possible source of the emission: a "fallback disk" or a disk that formed from materials of the parent star falling back into the neutron star after a supernova.
Credit: ESA/N. Tr’Ehnl (Pennsylvania State University)/NASA

Topics: Astrophysics, Infrared, Neutron Stars, Neutrons, X-rays

Space is filled with bizarre signals that we scramble to put meaning to — and now, researchers have detected yet another mysterious signal. This one emanated from near a neutron star, and for the first time, it's infrared.

So, what's nearby that could have created the weird signal? Scientists have a few ideas.

When a star reaches the end of its life, it typically undergoes a supernova explosion— the star collapses, and if it has enough mass, it will form a black hole. But if the star isn't massive enough, it will form a neutron star. [Supernova Photos: Great Images of Star Explosions]

Neutrons stars are very dense and, as their name suggests, are made up mostly of closely packed neutrons. Neutron stars can also be called "pulsars" if they are highly magnetized and rotate rapidly enough to emit electromagnetic waves, according to Space.com.

Typically, neutron stars emit radio waves or higher-energy waves such as X-rays, according a statement released by NASA yesterday (Sept. 17). But an international group of researchers from Penn State, the University of Arizona and Sabanci University in Turkey observed something interesting in NASA's Hubble Space Telescope data: a long signal of infrared light emitted near a neutron star, the researchers reported yesterday in The Astrophysical Journal.

This signal, they found, was about 800 light-years away and was "extended," meaning it was spread across a large stretch of space, unlike typical "point" signals from neutron stars that emit X-rays. Specifically, the signal stretched across 200 astronomical units (AU) of space, or 2.5 times the orbit of Pluto around the sun, according to a statement from Penn State. (One AU is the average distance from Earth to the sun — about 93 million miles, or 150 million kilometers.)

Weird Infrared Signal Emanates Across Space, But What Created It?
Yasemin Saplakoglu, Live Science