Light and gravitational waves produced by the same event – a pair of neutron stars exploding – have been detected for the first time by a huge international collaboration involving UCL researchers. (more…)
Tag Archives: light
Arctic excursion explores how sea life copes with continuous winter darkness
When the North Pole tilts away from the sun during the winter, the Arctic region plunges into weeks of continuous darkness. The sun never peeks above the horizon, casting only a twinge of blue twilight at midday, and the moon dimly illuminates the landscape at night if conditions are clear.
People living in this “polar night” have adapted to the darkness using artificial light, but how ocean inhabitants cope remains to be seen. (more…)
The internal circadian clock of a Drosophila (fruit fly) can be synchronised using vibrations, according to research published today in the journal Science. The study suggests that an animal’s own movements can influence its clock.
The circadian clock, which underlies the daily rhythms characterising most of our bodily functions, including the sleep cycle, is mainly set by diurnal changes in light and temperature. (more…)
AUSTIN, Texas — A team of researchers at The University of Texas at Austin’s Cockrell School of Engineering has built the first-ever circulator for sound. The team’s experiments successfully prove that the fundamental symmetry with which acoustic waves travel through air between two points in space (“if you can hear, you can also be heard”) can be broken by a compact and simple device.
“Using the proposed concept, we were able to create one-way communication for sound traveling through air,” said Andrea Alù, who led the project and is an associate professor and David & Doris Lybarger Endowed Faculty Fellow in the Cockrell School’s Department of Electrical and Computer Engineering. “Imagine being able to listen without having to worry about being heard in return.” (more…)
Researchers from North Carolina State University and the Chinese Academy of Sciences have found an easy way to modify the molecular structure of a polymer commonly used in solar cells. Their modification can increase solar cell efficiency by more than 30 percent.
Polymer-based solar cells have two domains, consisting of an electron acceptor and an electron donor material. Excitons are the energy particles created by solar cells when light is absorbed. In order to be harnessed effectively as an energy source, excitons must be able to travel quickly to the interface of the donor and acceptor domains and retain as much of the light’s energy as possible. (more…)
Researchers from North Carolina State University have developed a way to melt or “weld” specific portions of polymers by embedding aligned nanoparticles within the materials. Their technique, which melts fibers along a chosen direction within a material, may lead to stronger, more resilient nanofibers and materials.
Physicists Jason Bochinski and Laura Clarke, with materials scientist Joe Tracy, placed specifically aligned gold nanorods within a solid material. Gold nanorods absorb light at different wavelengths, depending upon the size and orientation of the nanorod, and then they convert that absorbed light directly into heat. In this case, the nanorods were designed to respond to light wavelengths of 520 nanometers (nm) in a horizontal alignment and 800 nm when vertically aligned. Human beings can see light at 520 nm (it looks green), while 808 nm is in the near infrared spectrum, invisible to our eyes. (more…)
Regional cloud changes, such as those that result in less rain during monsoons in India and those that indicate a widening of the tropics, may be as important to watch as the overall amount of cloud cover, new University of Washington research indicates.
Authors of the paper, led by Ryan Eastman, a UW research scientist in atmospheric sciences, set out to examine observations collected from weather stations around the world as a way to study the distribution of clouds. The research was recently published in the American Meteorological Society’s Journal of Climate. (more…)
One of the world’s first working circular particle accelerators returns to Berkeley Lab—75 years later.
Seventy-five years after one of the world’s first working cyclotrons was handed to the London Science Museum, it has returned to its birthplace in the Berkeley hills, where the man who invented it, Ernest O. Lawrence, helped launch the field of modern particle physics as well as the national laboratory that would bear his name, Lawrence Berkeley National Laboratory.
On Jan. 9, 1932 the brass cyclotron—which measures 26 inches from end to end and whose accelerating chamber measures just 11 inches in diameter—was successfully used to boost protons to energies of 1.22 million electron volts. Its return to Berkeley Lab caps a decades-long saga in which various parties endeavored to secure the cyclotron’s return from London, but the persistence of Pamela Patterson, who chronicles Berkeley Lab’s history as managing editor of its website, finally paid off. (more…)