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Heaviest tin isotopes provide insights into element synthesis

An international team of researchers, led by scientists from GSI/FAIR in Darmstadt, Germany, has studied r-process nucleosynthesis in measurements conducted at the Canadian research center TRIUMF in Vancouver. At the center of this work are the first mass measurements of three extremely neutron-rich tin isotopes: tin-136, tin-137 and tin-138. The results are published in the journal Physical Review Letters.

The high-precision measurements, combined with nucleosynthesis network calculations, help to better understand how are formed in the universe, especially through the rapid neutron capture process (the r-process) occurring in neutron star mergers.

The data reveal the neutron separation energy, which defines the path of the r-process on the nuclear chart. The study found unexpected changes in the behavior of tin nuclei beyond the magic neutron number N=82, specifically, a reduction in the pairing effect of the last two neutrons.

Sonic Booms in the Sky: How Scientists Use “Bolides” To Improve Planetary Defense

Faint booms from space help track incoming debris. But the path matters more than you think. Earth gains a little mass each year as space dust rains down from above, adding thousands of metric tons to the planet’s surface. In addition, roughly 50 tons of meteorites fall to Earth annually. Since t

AI-powered ChronoFlow uses stellar rotation rates to estimate stars’ ages

Figuring out the ages of stars is fundamental to understanding many areas of astronomy—yet, it remains a challenge since stellar ages can’t be ascertained through observation alone. So, astronomers at the University of Toronto have turned to artificial intelligence for help.

Their new , called ChronoFlow, uses a dataset of rotating stars in clusters and machine learning to determine how the speed at which a star rotates changes as it ages.

The approach, published recently in The Astrophysical Journal, predicts the ages of stars with an accuracy previously impossible to achieve with analytical models.

Climate satellite MethaneSAT backed by Bezos and Google fails in space after just 1 year

MethaneSAT was designed as a sort of check against commercial climate measurements in order to help policymakers independently verify industry emissions reports. “MethaneSAT is specifically designed to catalyze methane reductions by creating unprecedented transparency,” the mission’s website states.

EDF lists 10 mission partners credited with bringing the $88 million satellite to fruition, including BAE Systems, Harvard University, the New Zealand Space Agency, Bezos Earth Fund, Google and more. Though MethaneSAT is now out of service, mission operators say they’re still committed to turning the data they were able to collect into actionable results.

“We will continue to process data that we have retrieved from the satellite and will be releasing additional scenes of global oil and gas production region-scale emissions over the coming months,” EDT officials said. “To solve the climate challenge requires bold action and risk-taking and this satellite was at the leading edge of science, technology and advocacy. ”

Astronomers discover a super-Earth exoplanet orbiting a nearby star

Using NASA’s Transiting Exoplanet Survey Satellite (TESS), an international team of astronomers has discovered a new super-Earth exoplanet that orbits a nearby M dwarf star. The newfound alien world, designated TOI-1846 b, is about two times larger and four times more massive than Earth. The finding was detailed in a paper published June 23 on the arXiv preprint server.

Ocean model simulations shed light on long-term tritium distribution in released Fukushima water

Operators have pumped water to cool the nuclear reactors at the Fukushima Daiichi Nuclear Power Plant (FDNPP) since the accident in 2011 and treated this cooling water with the Advanced Liquid Processing System (ALPS), which is a state-of-the-art purification system that removes radioactive materials, except tritium.

As part of the water molecule, tritium radionuclide, with a half-life of 12.32 years, is very costly and difficult to remove. The ALPS-treated water was accumulating and stored at the FDNPP site and there is limited space to store this water. Therefore, in 2021, the Government of Japan announced a policy that included discharging the ALPS-treated water via an approximately one-kilometer-long tunnel into the ocean. Planned releases of the ALPS-treated water diluted with began in August 2023 and will be completed by 2050.

In a new numerical modeling study, researchers have revealed that the simulated increase in tritium concentration in the Pacific Ocean due to the tritium originating from the ALPS-treated water is about 0.1% or less than the tritium background concentration of 0.03−0.2 Bq/L in the vicinity of the site (within 25 km) and beyond.