The mysterious origin of our galaxy’s gold

 

Many astronomers now believe that the space-quaking merger of two neutron stars can forge the universe’s supply of heavy elements. 

In our galaxy, neutron star mergers could happen as rarely as once every hundred million years, or as often as once every 10 thousand years—rates that differ by a factor of 10,000. “The thing that shook me is: The people who were saying neutron star mergers are going to explain the r process (rapid neutron capture causing nuclei to form heavy elements including uranium and gold) were also taking this highest rate,” said Christopher Fryer, an astrophysicist at Los Alamos National Laboratory.

When Fryer and colleagues used more moderate guesses about how often neutron star mergers occur and how much r-process material they yield, they found that neutron star mergers can explain only 1 percent of the r-process elements observed in the universe. (Full story)

Research could pave way for novel solar cells

Solar cells and photodetectors could soon be made from new types of materials based on semiconductor quantum dots, thanks to new insights based on ultrafast measurements capturing real-time photoconversion processes, according to the Los Alamos National Laboratory.

“Our latest ultrafast electro-optical spectroscopy studies provide unprecedented insights into the photophysics of quantum dots, and this new information helps perfect the materials’ properties for applications in practical photoconversion devices,” says lead researcher Victor Klimov, a physicist specializing in semiconductor nanocrystals at the national lab. (Full story)

Chemists discover new oxidation state of plutonium

Electron micrograph of single crystalline

plutonium, LANL image.

The chemistry of plutonium — a transuranic radioactive chemical element with symbol Pu and atomic number 94 — has been extensively studied at Los Alamos as part of its essential national security mission since the Manhattan Project of the 1940s, revealing its chemistry to be among the most complex of all elements.

Six oxidation states are known and have been verified: 0 (metallic form) and +3, +4, +5, +6, +7 in molecular systems.

The current work demonstrates that a seventh formal oxidation state (+2) has now been accessed and verified, representing an unexpected new chemical form of plutonium. (Full story)

LANL installs pod for breastfeeding moms, first of its kind in New Mexico

A Mamava unit was installed at the Laboratory,

the first of its kind in New Mexico.

Los Alamos National Laboratory has found a new, more accommodating way to support its breastfeeding employees.

The Mamava pod was installed in the Oppenheimer Study Center last week and LANL already plans to install another in the coming weeks in a more secure area. (Full story)

Breaking the ‘speed limit': Simulation shows monster black holes' rapid growth

Quasar halo simulation containing a supermassive black hole. LANL image.

"It turns out that while supermassive black holes have a growth speed limit, certain types of massive stars do not," said Joseph Smidt, a researcher at the theoretical design division of Los Alamos National Laboratory and the first author on the new work. "We asked, what if we could find a place where stars could grow much faster, perhaps to the size of many thousand suns; could they form supermassive black holes in less time?"

The researchers compared their models to the most distant known energetic galactic center, called a quasar, and one of the most massive of those objects, which is also ancient, to see whether that method could have quickly grown them to full size. (Full Story)

Also from HPC Wire and Space Daily

Quantum dot solar inefficiency source found

Quantum dot solar cells could become more efficient, now that the Los Alamos Lab has uncovered a mechanism that has been holding them back.

The dots are made form electro-optically active materials whose size as well as composition controls the photon energy that they interact with, allowing their absorption (and emission) wavelength to be tuned by particle size. They can also be tuned to deliver multiple electron-hole pairs from one photon, which has allowed quantum dot solar cells to operate at 10% efficiency, according to Los Alamos. (Full Story)

Watch the video

'Flying saucer' quantum dots hold secret to brighter, better lasers

Spherical core of the quantum dot nanoparticle, UT image.

Fresh insights into living cells, brighter video projectors and more accurate medical tests are just three of the innovations that could result from a new way of fabricating lasers.

The new method, developed by an international research team from U of T Engineering, Vanderbilt University, the Los Alamos National Laboratory and others, produces continuous laser light that is brighter, less expensive and more tuneable than current devices by using nanoparticles known as quantum dots. (Full Story)

Uncovering the origins of cancer

Ludmil Alexandrov, New Mexican photo.        

“The question that bothers me and interests me the most is what causes cancer,” said Ludmil Alexandrov, 30, a J. Robert Oppenheimer fellow at Los Alamos, who will spend the next five years studying the mutational fingerprints of more than 5,000 cancer patients around the world.

“If you take any given cancer patient, can you say cancer is caused by A, B, C, D?” Alexandrov said, adding that is “a puzzle in my head that we are trying to solve.”

With the exclusion of cancer related to smoking, Alexandrov said, “Eight out of 10 cancers we cannot explain; we don’t know what caused them.” (Full Story)

Less radiation in inner Van Allen belt than previously believed

Van Allen Probes circle radiation belts, LANL illustration.

The inner Van Allen belt has less radiation than previously believed, according to a recent study in the Journal of Geophysical Research. Observations from NASA's Van Allen probes show the fastest, most energetic electrons in the inner radiation belt are actually much rarer and harder to find than scientists expected. This is good news for spacecraft that are orbiting in the region and can be damaged by high levels of radiation. The results will also help scientists better understand -- and detect -- effects from high-altitude nuclear explosions. (Full Story)

Also from the LA Daily Post

Can our grid withstand a solar storm?

When the last really big solar storm hit Earth in 1921, the Sun ejected a burst of plasma and magnetic structures like Zeus hurling a thunderbolt from Mount Olympus. Earth’s magnetic field funneled a wave of electrically charged particles toward the ground, where they induced a current along telegraph lines and railroad tracks that set fire to telegraph offices and burned down train stations.

Los Alamos National Laboratory has been studying space weather for more than 50 years as part of our national security mission to monitor nuclear testing around the globe, and part of that work includes studying how the radiation-saturated environment of near space can affect technology and people. (Full Story)

Scanning tunneling microscopy reveals unexpected optical phonon effect

Optical phonon condensate droplets, LANL image.         

"We did not predict this B-E condensate in our model. This is an absolutely new observation," said Alexander "Sasha" Balatsky of Los Alamos National Laboratory, a coauthor on the paper with a research team from Air Force Research Laboratory, The Pennsylvania State University, Los Alamos National Laboratory and the Nordita Center for Quantum Materials, KTH Royal Institute of Technology and Stockholm University.

The new substance may be useful for phonon-based quantum computers, and it may also shed light on the conditions required to form biological Fröhlich condensates of collective modes. (Full Story)

Featured R&D 100 Award Winner PuLMo

Section of the Pulmonary Lung Model, LANL image.

To avoid lung disease complications, scientists and engineers at Los Alamos National Laboratory have developed PuLMo: Pulmonary Lung Model—a miniature, tissue-engineered lung platform that precisely mimics the response of human lungs to pharmaceuticals and other agents.

The principal application of PuLMo, a winner of a 2016 R&D 100 award, is to revolutionize the reliability of drug toxicity assessments and better predict the efficacy of a new drug in humans. Since PuLMo is the size of an actual human lung, such miniaturization makes it possible to evaluate multiple units at a time. (Full Story)

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Science on the Hill: Dark matter detective work

The High-Altitude Water Cherenkov Observatory in

the mountains of Mexico, from the New Mexican.

Fourteen thousand feet above sea level near a volcanic peak in Mexico sits a unique astronomical observatory. Instead of peering into space with a glass lens, it uses 300 huge barrels of water. And instead of focusing light, digital sensors inside each barrel detect a ghostly blue light called Cherenkov radiation from high-energy particles zipping through the water.

At this High-Altitude Water Cherenkov Observatory, better known as HAWC, a team of astrophysicists from Los Alamos National Laboratory and their colleagues are sifting through data from those mountain-top water barrels looking for the fingerprint of one of the most elusive yet abundant quarries in the universe: Dark matter. (Full story)

2D layered hybrid perovskite material enhances effectiveness for LEDs and solar cells

2D Perovskite structure, LANL image.               

Researchers at Los Alamos National Laboratory and their partners are developing ground-breaking 2D layered hybrid perovskites that allow higher level of freedom in designing and fabricating efficient optoelectronic devices.

The 2D, near-single-crystalline "Ruddlesden-Popper" thin films have an out-of-plane orientation so that unrestrained charge movement takes place across the perovskite layers in planar devices.

At the edges of the perovskite layers, the team detected "layer-edge-states," which are crucial to both high fluorescence efficiency (a few tens of percent) for LEDs and high efficiency of solar cells (>12 %). (Full story)

Also from CleanTechnica

Scientists discover oxidation state for molecular plutonium

Researchers have identified the +2 oxidation state in a molecular system of plutonium. The findings by researchers at Los Alamos National Laboratory in collaboration with the University of California- Irvine provide a significant step towards a more complete understanding of chemical trends across the actinide series and ultimately will provide knowledge about how to manipulate and control oxidation-state chemistry and electronic structure. (Full story)

Raving about robots

Robo Rave Competition, RG Sun photo.

Janelle Vigil-Maestas from the Los Alamos National Laboratory Community Programs Office, said her Office started sponsoring the event several years ago, to give students practice ahead of the much larger annual, international contest held each year in Albuquerque. This year, it will be on May 5 and 6.

“We brought it to Northern because we had a lot of students that were starting teams and they didn’t have experience competing,” she said. (Full story)

LANL donation adding to UNM supercomputing power

The new system given to UNM from

Los Alamos. UNM photo.

The machine was acquired from LANL through the National Science Foundation-sponsored PR0bE project, which is run by the New Mexico Consortium (NMC). The NMC, comprising UNM, New Mexico State, and New Mexico Tech universities, engages universities and industry in scientific research in the nation's interest and to increase the role of LANL in science, education and economic development. (Full story)

Oldest, biggest black holes may have come from enormous stars

European Organization for Astronomical Research illustration.           

The earliest supermassive black holes may have been big to start with. If so, it would help explain the recent detection of such beasts within a billion years of the big bang.

In principle, though, stars can gain mass faster than black holes. Joseph Smidt at the Los Alamos National Laboratory in New Mexico and his colleagues say this could explain the presence of supermassive black holes so early on.

“Other results showed that you can get the right mass – but black holes are more than mass,” says Smidt. “We’ve shown that we can match several other independently observed features.” (Full Story)

See the NewScientist video on YouTube

Machine-learning algorithm predicts laboratory earthquakes

Random Forest approach for predicting time remaining before failure.           

Bertrand Rouet-Leduc at Los Alamos National Laboratory [has] trained a machine-learning algorithm to spot the tell-tale signs that a laboratory earthquake is about to give way using only the sounds it emits under strain.  The team is cautious about the new technique’s utility for real earthquakes, but the work opens up new avenues of research in this area.

Rouet-Leduc and collaborators created artificial earthquakes in their lab by pulling on one block sandwiched between two others. At the interface between the blocks, they packed a mixture of rocky material, called gouge material, to simulate the properties of real faults. (Full Story)

Perovskite edges can be tuned for optoelectronic performance

2D Perovskite structure. LANL illustration.

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating innovative 2D layered hybrid perovskites that allow greater freedom in designing and fabricating efficient optoelectronic devices. Industrial and consumer applications could include low cost solar cells, LEDs, laser diodes, detectors, and other nano-optoelectronic devices. (Full Story)

See the Los Alamos video on YouTube

Unexpected oxidation state for molecular plutonium discovered

Scientists from Los Alamos National Laboratory and UC Irvine study a new oxidation state of plutonium. LANL Photo

Researchers at Los Alamos National Laboratory in collaboration with the University of California - Irvine (UCI) have uncovered a significant new chemical attribute of plutonium, the identification and structural verification of the +2 oxidation state in a molecular system.

"This finding marks out plutonium, already known for its extremely complex chemistry, as the actinide element with the largest number of confirmed oxidation states," said Andrew Gaunt, lead Los Alamos investigator on the project along with Stosh Kozimor. (Full Story)

Jaqueline L. Kiplinger receives IUPAC 2017 Distinguished Women In Chemistry Award

Jaqueline Kiplinger, LANL photo.

Los Alamos National Laboratory Fellow Jaqueline Kiplinger was recognized this week with the International Union of Pure and Applied Chemistry (IUPAC) 2017 Distinguished Women in Chemistry or Chemical Engineering award. Kiplinger was one of 12 women recognized this year internationally and the only recipient of this honor from the United States. (Full Story)
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