Lifeboat Foundation

Findings could help explain how air pollutants interact with the atmosphere.

Researchers at the University of British Columbia, University of California Irvine, and McGill University have discovered three liquid phases in aerosol particles, changing our understanding of air pollutants in the Earth’s atmosphere.

While aerosol particles were known to contain up to two liquid phases, the discovery of an additional liquid phase may be important to providing more accurate atmospheric models and climate predictions. The study was published recently in PNAS.

Starburst galaxies, active galactic nuclei and tidal disruption events (from left) have emerged as top candidates for the dominant source of ultrahigh-energy cosmic rays.

In the 1930s, the French physicist Pierre Auger placed Geiger counters along a ridge in the Alps and observed that they would sometimes spontaneously click at the same time, even when they were up to 300 meters apart. He knew that the coincident clicks came from cosmic rays, charged particles from space that bang into air molecules in the sky, triggering particle showers that rain down to the ground. But Auger realized that for cosmic rays to trigger the kind of enormous showers he was seeing, they must carry fantastical amounts of energy — so much that, he wrote in 1939, “it is actually impossible to imagine a single process able to give to a particle such an energy.”

Upon constructing larger arrays of Geiger counters and other kinds of detectors, physicists learned that cosmic rays reach energies at least 100000 times higher than Auger supposed.

Continue reading “Cosmic Map of Ultrahigh-Energy Particles Points to Long-Hidden Treasures” »

Nuclear physicists make new, high-precision measurement of the layer of neutrons that encompass the lead nucleus, revealing new information about neutron stars.

Nuclear physicists have made a new, highly accurate measurement of the thickness of the neutron “skin” that encompasses the lead nucleus in experiments conducted at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility and just published in Physical Review Letters. The result, which revealed a neutron skin thickness of .28 millionths of a nanometer, has important implications for the structure and size of neutron stars.

The protons and neutrons that form the nucleus at the heart of every atom in the universe help determine each atom’s identity and properties. Nuclear physicists are studying different nuclei to learn more about how these protons and neutrons act inside the nucleus. The Lead Radius Experiment collaboration, called PREx (after the chemical symbol for lead, Pb), is studying the fine details of how protons and neutrons are distributed in lead nuclei.

Circa 2020 o.o!

Researchers have succeeded in creating an efficient quantum-mechanical light-matter interface using a microscopic cavity. Within this cavity, a single photon is emitted and absorbed up to 10 times by an artificial atom. This opens up new prospects for quantum technology, report physicists at the University of Basel and Ruhr-University Bochum in the journal Nature.

Quantum physics describes photons as light particles. Achieving an interaction between a single photon and a single atom is a huge challenge due to the tiny size of the atom. However, sending the photon past the atom several times by means of mirrors significantly increases the probability of an interaction.

Continue reading “Efficient Quantum-Mechanical Interface Leads to a Strong Interaction Between Light and Matter” »

Circa 2020 o.,.o!

By Leah Crane.

Google researchers have used a quantum computer to simulate a chemical reaction for the first time. The reaction is a simple one, but this marks a step towards finding a practical use for quantum computers.

Continue reading “Google performed the first quantum simulation of a chemical reaction” »

Nuclear physicists have made a new, highly accurate measurement of the thickness of the neutron “skin” that encompasses the lead nucleus in experiments conducted at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility and just published in Physical Review Letters. The result, which revealed a neutron skin thickness of .28 millionths of a nanometer, has important implications for the structure and size of neutron stars.

The protons and neutrons that form the nucleus at the heart of every atom in the universe help determine each atom’s identity and properties. Nuclear physicists are studying different nuclei to learn more about how these protons and neutrons act inside the nucleus. The Lead Radius Experiment collaboration, called PREx (after the chemical symbol for lead, Pb), is studying the fine details of how protons and neutrons are distributed in lead nuclei.

“The question is about where the neutrons are in lead. Lead is a heavy nucleus—there’s extra neutrons, but as far as the nuclear force is concerned, an equal mix of protons and neutrons works better,” said Kent Paschke, a professor at the University of Virginia and experiment co-spokesperson.

Exploring and manipulating the behavior of polar vortices in material may lead to new technology for faster data transfer and storage. Researchers used the Advanced Photon Source at Argonne and the Linac Coherent Light Source at SLAC to learn more.

Our high-speed, high-bandwidth world constantly requires new ways to process and store information. Semiconductors and magnetic materials have made up the bulk of data storage devices for decades. In recent years, however, researchers and engineers have turned to ferroelectric materials, a type of crystal that can be manipulated with electricity.

In 2016, the study of ferroelectrics got more interesting with the discovery of polar vortices — essentially spiral-shaped groupings of atoms — within the structure of the material. Now a team of researchers led by the U.S. Department of Energy’s (DOE) Argonne National Laboratory has uncovered new insights into the behavior of these vortices, insights that may be the first step toward using them for fast, versatile data processing and storage.

Circa 2020 o.o

Independent spectroscopy studies give equivocal results.

We consider the dynamics of a charged particle (e.g., an electron) oscillating in a laser field in flat spacetime and describe it in terms of the variable mass metric. By applying Einstein’s equivalence principle, we show that, after representing the electron motion in a time-dependent manner, the variable mass metric takes the form of the Friedmann–Lemaître–Robertson–Walker metric. We quantize a pseudo-scalar field in this spacetime and derive the production rate of electrically neutral, spinless particles. We show that this approach can provide an alternative experimental method to axion searches.