SPACE
A leap in lunar exploration: HI-13 accelerator enhanced capability to uncovers clues from supernovae in lunar dust
Researchers at the China Institute of Atomic have made significant advancements in the study of cosmic events, such as supernovae that occurred millions of years ago.
NUCLEAR SCIENCE AND TECHNIQUES
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THE TARGET CHAMBER WAS EQUIPPED WITH A COLLIMATOR, A TARGET HOLDER, AND A FARADAY CUP. SI3N4 FOIL DEGRADERS WERE INSTALLED ON THE TARGET HOLDER. THE Q3D MAGNETIC SPECTROGRAPH IS ABLE TO ROTATE AROUND THE TARGET CHAMBER.
RESEARCHERS AT THE CHINA INSTITUTE OF ATOMIC ENERGY (CIAE) HAVE SIGNIFICANTLY ENHANCED THE METHOD OF DETECTING IRON-60 (60FE), A RARE ISOTOPE FOUND IN LUNAR SAMPLES, USING THE HI-13 TANDEM ACCELERATOR. THIS ACHIEVEMENT PAVES THE WAY OF DETECTING 60FE IN LUNAR SAMPLES FOR A DEEPER UNDERSTANDING OF COSMIC EVENTS LIKE SUPERNOVAE THAT OCCURRED MILLIONS OF YEARS AGO. HTTPS://DOI.ORG/10.1007/S41365-024-01453-X
view moreCREDIT: CREDIT: CHINA INSTITUTE OF ATOMIC ENERGY
Researchers at the China Institute of Atomic Energy (CIAE) have significantly enhanced the method of detecting iron-60 (60Fe), a rare isotope found in lunar samples, using the HI-13 tandem accelerator. This achievement paves the way of detecting 60Fe in lunar samples for a deeper understanding of cosmic events like supernovae that occurred millions of years ago.
Enhanced Detection of 60Fe on the Moon
The study, led by Bing Guo, utilized a refined accelerator mass spectrometry (AMS) technique to detect 60Fe, a rare isotope produced by supernovae and found in samples returned from the Moon. The enhanced AMS system, equipped with a Wien filter, successfully identified 60Fe in simulation samples with sensitivity levels previously unachievable. This finding demonstrates a detection sensitivity better than 4.3 × 10−14 and potentially reaching 2.5 × 10−15 in optimal conditions.
Tackling a Cosmic Challenge
For decades, the challenge of detecting low-abundance isotopes like 60Fe in lunar samples have stumped scientists due to the isotope's scarcity and the presence of interfering elements. The traditional methods fell short in sensitivity. The latest modifications at the CIAE's HI-13 tandem accelerator facility represent a significant step forward. Bing Guo shared, "Our team agreed that the only way to track historical supernovae events accurately was by pushing the boundaries of what our equipment could do. The installation of the Wien filter could be a game-changer for us."
From Lunar Dust to Cosmic Revelations
The findings of this research extend beyond the academic realm, offering insights into the processes that shape our universe. The ability to measure minute quantities of 60Fe on the Moon provides a direct link to studying past supernovae events that have occurred nearby. These discoveries have implications for astrophysics, offering a new lens through which to view the history and evolution of stars.
Looking to the Future: Expanding Lunar Science
Looking ahead, the CIAE research team plans to refine their techniques further to improve the sensitivity of their measurements. Enhancements in ion source and beam transmission efficiencies are expected to push detection capabilities even further. "Our next goal is to optimize our entire AMS system to reach even lower detection limits. Every bit of increased sensitivity opens up a universe of possibilities," explained Guo.
The successful development of this enhanced AMS method contributes to both lunar research and the study of interstellar phenomena. As researchers continue to refine this technology, our understanding of the universe's history grows deeper, proving once again that our journey through the cosmos is far from over.
A Wien filter with a maximum voltage of ±60 kV and a maximum magnetic field of 0.3 T was added after the switching magnet to lower the detection background for the low abundance nuclides.
Researchers at the China Institute of Atomic Energy (CIAE) have significantly enhanced the method of detecting iron-60 (60Fe), a rare isotope found in lunar samples, using the HI-13 tandem accelerator. This achievement paves the way of detecting 60Fe in lunar samples for a deeper understanding of cosmic events like supernovae that occurred millions of years ago. https://doi.org/10.1007/s41365-024-01453-x
The cathode holder disk is part of the NEC multi-cathode source of negative ions by cesium sputtering. Cathodes of 60Fe samples and blank samples were installed on the holder disk.
Researchers at the China Institute of Atomic Energy (CIAE) have significantly enhanced the method of detecting iron-60 (60Fe), a rare isotope found in lunar samples, using the HI-13 tandem accelerator. This achievement paves the way of detecting 60Fe in lunar samples for a deeper understanding of cosmic events like supernovae that occurred millions of years ago. https://doi.org/10.1007/s41365-024-01453-x
Professor Guo, professor He, and professor Yan, from the Nuclear Analysis Research Center for Lunar Sample at the Department of Nuclear Physics of the China Institute of Atomic Energy, examine experimental results.
Researchers at the China Institute of Atomic Energy (CIAE) have significantly enhanced the method of detecting iron-60 (60Fe), a rare isotope found in lunar samples, using the HI-13 tandem accelerator. This achievement paves the way of detecting 60Fe in lunar samples for a deeper understanding of cosmic events like supernovae that occurred millions of years ago. https://doi.org/10.1007/s41365-024-01453-x
CREDIT
Credit: China Institute of Atomic Energy
JOURNAL
Nuclear Science and Techniques
METHOD OF RESEARCH
Experimental study
SUBJECT OF RESEARCH
Not applicable
ARTICLE TITLE
Stepped-up development of accelerator mass spectrometry method for the detection of 60Fe with the HI-13 tandem accelerator
ARTICLE PUBLICATION DATE
25-May-2024
Cosmic light shows decoded: HKU space scientists unravel the unified framework for diverse aurorae across planets unlocking pathways for better space weather prediction
THE UNIVERSITY OF HONG KONG
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A CONCEPTUAL IMAGE ILLUSTRATING THE DIFFERENT AURORA BETWEEN EARTH AND JUPITER. IMAGE CREDIT: PROFESSOR ZHONGHUA YAO
view moreCREDIT: THE UNIVERSITY OF HONG KONG
Unravelling the diversity of planetary aurorae
Earth, Saturn and Jupiter all generate their own dipole-like magnetic field, resulting in funnel-canopy-shaped magnetic geometry that leads the space’s energetic electrons to precipitate into polar regions and cause polar auroral emissions. On the other hand, the three planets differ in many aspects, including their magnetic strength, rotating speed, solar wind condition, moon activities, etc. It is unclear how these different conditions are related to the different auroral structures that have been observed on those planets for decades.
Using three-dimensional magnetohydrodynamics calculations, which model the coupled dynamics of electrically conducting fluids and electromagnetic fields, the research team assessed the relative importance of these conditions in controlling the main auroral morphology of a planet. Combining solar wind conditions and planetary rotation, they defined a new parameter that controls the main auroral structure, which for the first time, nicely explains the different auroral structures observed at Earth, Saturn and Jupiter.
Stellar winds’ interaction with planetary magnetic fields is a fundamental process in the universe. The research can be applied to grasp the space environments of Uranus, Neptune, and even exoplanets.
‘Our study has revealed the complex interplay between solar wind and planetary rotation, providing a deeper understanding of aurorae across different planets. These findings will not only enhance our knowledge of the aurorae in our solar system but also be potentially extend to the study of aurorae in exoplanetary systems,’ said Professor Binzheng Zhang, Principal Investigator and the first author of the project.
‘We have learnt that the aurorae at Earth and Jupiter are different since 1979, it is a big surprise that they can be explained by a unified framework,’ added Professor Denis GRODENT, Head of the STAR institute at the University of Liege and co-author of the project.
By advancing our fundamental understanding of how planetary magnetic fields interact with the solar wind to drive auroral displays, this research has important practical applications for monitoring, predicting, and exploring the magnetic environments of the solar system.
This study also represents a significant milestone in understanding auroral patterns across planets that deepened our knowledge of diverse planetary space environments, paving the way for future research into the mesmerising celestial light shows that continue to capture our imagination.
The journal paper ‘A unified framework for global auroral morphologies of different planets’ can be accessed here: https://www.nature.com/articles/s41550-024-02270-3
For media enquiries, please contact Ms Casey To, External Relations Officer (tel: 3917 4948; email: caseyto@hku.hk / Ms Cindy Chan, Assistant Director of Communications of HKU Faculty of Science (tel: 39175286; email: cindycst@hku.hk).
Images download and captions: https://www.scifac.hku.hk/press
JOURNAL
Nature Astronomy
METHOD OF RESEARCH
Experimental study
SUBJECT OF RESEARCH
Not applicable
ARTICLE PUBLICATION DATE
30-May-2024
Rethinking the sun’s cycles
New physical model reinforces planetary hypothesis
HELMHOLTZ-ZENTRUM DRESDEN-ROSSENDORF
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THE SUN IS CURRENTLY APPROACHING A MAXIMUM ACTIVITY IN THE 11-YEAR “SCHWABE CYCLE” AGAIN, HERE A SOLAR ORBITER IMAGE FROM OCTOBER 2023.
view moreCREDIT: ESA & NASA/SOLAR ORBITER/EUI TEAM
Researchers at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and the University of Latvia have posited the first comprehensive physical explanation for the sun’s various activity cycles. It identifies vortex-shaped currents on the sun, known as Rossby waves, as mediators between the tidal influences of Venus, Earth as well as Jupiter and the sun’s magnetic activity. The researchers thus present a consistent model for solar cycles of different lengths – and another strong argument to support the previously controversial planetary hypothesis. The results have now been published in the journal Solar Physics (DOI: 10.1007/s11207-024-02295-x).
Although the sun, being near to us, is the best researched star, many questions about its physics have not yet been completely answered. These include the rhythmic fluctuations in solar activity. The most famous of these is that, on average, the sun reaches a radiation maximum every eleven years – which experts refer to as the Schwabe cycle. This cycle of activity occurs because the sun's magnetic field changes during this period and eventually reverses polarity. This, in itself, is not unusual for a star – if it weren’t for the fact that the Schwabe cycle is remarkably stable.
The Schwabe cycle is overlaid by other, less obvious fluctuations in activity ranging from a few hundred days to several hundred years, each named after their discoverers. Although there have already been various attempts to explain these cycles and mathematical calculations, there is still no comprehensive physical model.
Planets set the beat
For some years, Dr. Frank Stefani of HZDR’s Institute of Fluid Dynamics has been an advocate of the “planetary hypothesis” because it is clear that the planets’ gravity exerts a tidal effect on the sun, similar to that of the moon on the Earth. This effect is strongest every 11.07 years: whenever the three planets Venus, Earth and Jupiter are aligned with the sun in a particularly striking line, comparable to a spring tide on Earth when there is a new or full moon. This coincides conspicuously with the Schwabe cycle.
The sun’s magnetic field is formed by complex movements of the electrically conducting plasma inside the sun. “You can think of it like a gigantic dynamo. While this solar dynamo generates an approximately 11-year activity cycle in its own right, we think the planets’ influence then intervenes in the workings of this dynamo, repeatedly giving it a little push and thus forcing the unusually stable 11.07-year rhythm on the sun,” Stefani explains.
Several years ago, he and his colleagues discovered strong evidence of a clocked process of this kind in the available observation data. They were also able to correlate various solar cycles with the movement of the planets just using mathematical methods. At first, however, the correlation could not be sufficiently explained physically.
Rossby waves on the sun act as intermediaries
“We have now found the underlying physical mechanism. We know how much energy is required to synchronize the dynamo, and we know that this energy can be transferred to the sun by so-called Rossby waves. The great thing is that we can now not only explain the Schwabe cycle and longer solar cycles but also the shorter Rieger cycles that we hadn’t even considered previously,” says Stefani.
Rossby waves are vortex-shaped currents on the sun similar to the large-scale wave movements in the Earth's atmosphere that control high- and low-pressure systems. The researchers calculated that the tidal forces during the spring tides of two of each of the three planets Venus, Earth and Jupiter had exactly the right properties to activate Rossby waves – an insight with many consequences: first of all, these Rossby waves then achieve sufficiently high speeds to give the solar dynamo the necessary impetus; secondly, this occurs every 118, 193 and 299 days in accordance with the Rieger cycles that have been observed on the sun. And thirdly, all additional solar cycles can be calculated on this basis.
All cycles explained by a single model
This is where mathematics comes in: The superimposition of the three short Rieger cycles automatically produces the prominent 11.07-year Schwabe cycle. And the model even predicts long-term fluctuations of the sun because the movement of the sun around the solar system’s center of gravity causes a so-called beat period of 193 years on the basis of the Schwabe cycle. This corresponds to the order of magnitude of another cycle that has been observed, the Suess-de Vries cycle.
In this context, the researchers discovered an impressive correlation between the 193-year period that had been calculated and periodic fluctuations in climate data. This is another robust argument for the planetary hypothesis because “the sharp Suess-de Vries peak at 193 years can hardly be explained without phase stability in the Schwabe cycle, which is only present in a clocked process,” Stefani estimates.
Does this mean the question as to whether the sun follows the planets’ beat has finally been answered? Stefani says, “We’ll probably only be 100 percent certain when we have more data. But the arguments in favor of a process clocked by the planets are now very strong.”
Publication:
F. Stefani, G. M. Horstmann, M. Klevs, G. Mamatsashvili, T. Weier: Rieger, Schwabe, Suess-de Vries: The Sunny Beats of Resonance, in Solar Physics, 2024 (DOI: 10.1007/s11207-024-02295-x)
Further information:
Dr. Frank Stefani
Institute of Fluid Dynamics at HZDR
Phone: +49 351 260 3069 | Email: f.stefani@hzdr.de
Medienkontakt:
Simon Schmitt | Head
Department of Communications and Media Relations at HZDR
Phone: +49 351 260 3400 | Mob.: +49 175 874 2865 | Email: s.schmitt@hzdr.de
The Helmholtz-Zentrum Dresden-Rossendorf (HZDR) performs – as an independent German research center – research in the fields of energy, health, and matter. We focus on answering the following questions:
- How can energy and resources be utilized in an efficient, safe, and sustainable way?
- How can malignant tumors be more precisely visualized, characterized, and more effectively treated?
- How do matter and materials behave under the influence of strong fields and in smallest dimensions?
To help answer these research questions, HZDR operates large-scale facilities, which are also used by visiting researchers: the Ion Beam Center, the Dresden High Magnetic Field Laboratory and the ELBE Center for High-Power Radiation Sources.
HZDR is a member of the Helmholtz Association and has six sites (Dresden, Freiberg, Görlitz, Grenoble, Leipzig, Schenefeld near Hamburg) with almost 1,500 members of staff, of whom about 670 are scientists, including 220 Ph.D. candidates.
JOURNAL
Solar Physics
METHOD OF RESEARCH
Observational study
SUBJECT OF RESEARCH
Not applicable
ARTICLE TITLE
Rieger, Schwabe, Suess-de Vries: The Sunny Beats of Resonance
