IMAGE:
60Fe yield in 18 solar mass star. Blue lines (LMP) are calculations based on previous decay rate, red lines (present work) are those based on the new measurement.. view more
Credit: Physical Review Letters
Researchers from the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences and their collaborators have recently made great progress in the study of the stellar beta-decay rate of
59Fe, which constitutes an important step towards understanding
60Fe nucleosynthesis in massive stars. The results were published in
Physical Review Letters on April 12.
Radioactive nuclide
60Fe plays an essential role in nuclear astrophysical studies. It is synthesized in massive stars by successive neutron captures on a stable nucleus of
E-Mail
EUGENE, Ore. April 16, 2021 University of Oregon physicists have developed a new method to manipulate sound stop it, reverse it, store it and even use it later in synthetic composite structures known as metamaterials.
The discovery was made using theoretical and computational analysis of the mechanical vibrations of thin elastic plates, which serve as the building blocks for the proposed design. The physicists, Pragalv Karki and Jayson Paulose, also developed a simpler minimal model consisting of springs and masses demonstrating the same signal manipulation ability. There have been a lot of mechanisms that can guide or block the transmission of sound waves through a metamaterial, but our design is the first to dynamically stop and reverse a sound pulse, said Karki, a postdoctoral researcher in the UO s Department of Physics and Institute for Fundamental Science.
E-Mail
IMAGE: Launch of SM-3 Block IB interceptor from guided-missile cruiser USS Lake Erie (CG 70). view more
Credit: U.S. Navy
From engineered pandemics to city-toppling cyber attacks to nuclear annihilation, life on Earth could radically change, and soon. Scientists will forecast the fate of the planet at a press conference during the 2021 APS April Meeting. Our Earth is 45 million centuries old. But this century is the first when one species ours can determine the biosphere s fate, said Martin Rees, the United Kingdom s Astronomer Royal and a founder of the Centre for the Study of Existential Risks at Cambridge University. Our globally-linked society is vulnerable to the unintended consequences of powerful new technologies not only nuclear, but (even more) biotech, cyber, advanced AI, space technology, he added.
E-Mail
IMAGE: The night sky dances with auroras over Dark Sector Laboratory at the Amundsen-Scott South Pole Station at the geographic South Pole. On the very far right, inside the silver ground. view more
Credit: Robert Schwarz
Faced with the tragic loss of the Arecibo observatory in Puerto Rico and the often prohibitive cost of satellite missions, astronomers are searching for savvy alternatives to continue answering fundamental questions in physics.
At a press conference during the 2021 APS April Meeting, they will reveal new tactics across both hemispheres for illuminating gravitational waves and dark matter.
Shining the oldest light in the universe on dark matter