Russian Researchers Obtain New Data on Solar Magnetic Field Asymmetry
Researchers from the Institute of Earthquake Prediction Theory and Mathematical Geophysics (Russian Academy of Science) and HSE University have proven that asymmetry between meridional flows in the northern and southern hemispheres of the Sun depends on the anomalies of the solar magnetic field. Research undertaken by Elena Blanter and Mikhail Snirman reveals new aspects of the importance of solar magnetic field asymmetry for predicting the anomalies of the Sun’s activity. The article has been published in Solar Physics.
Researchers from the Institute of Earthquake Prediction Theory and Mathematical Geophysics (Russian Academy of Science) and HSE University have proven that asymmetry between meridional flows in the northern and southern hemispheres of the Sun depends on the anomalies of the solar magnetic field. Research undertaken by Elena Blanter and Mikhail Snirman reveals new aspects of the importance of solar magnetic field asymmetry for predicting the anomalies of the Sun’s activity. The article has been published in Solar Physics.
The Sun’s magnetic field plays a pivotal role in human life. Forecasting magnetic storms is essential for aviation, protection of ground technical systems, space flight missions and launches of research and commercial satellites. The mechanisms of the solar magnetic field have yet to be fully explored due to the complexity of processes inside the Sun and the impossibility of performing direct measurements.
The solar magnetic field forms under the dynamo mechanism in the Sun’s convection zone. Figure 1 shows that the convection zone is a little less than one-third of the Sun’s radius and is located at the surface of this star. Above the convection zone is the Sun’s corona, which can be seen during a solar eclipse. The dynamo theory provides an explanation for the 11-year cycles of solar magnetic activity, which can be observed due to changes in the number and location of sunspots on the Sun. A large meridional flow in the convection zone affects that dynamo mechanism.
The meridional flow can be represented as two giant circulation cells, one cell for each hemisphere. At the Sun’s surface, the flow is directed from the equator to the poles, while inside the convection zone, plasma circulates back to the equator. The research shows that the meridional flow appears to be a much more complex process—a single flow can be a sum of smaller circulation cells, just like a system of coupled gears.
The research uses the Kuramoto model, named after the Japanese physicist Yoshiki Kuramoto, to describe the system of such coupled circulation cells in the Sun’s physics. The classic model describes synchronization of coupled oscillatory systems consisting of several cells to determine the conditions under which the circulation cell system may be regarded as a single whole and when it falls into independent unrelated motions.
The authors of the article have previously studied the long-term evolution of meridional flows in the Sun’s northern and southern hemispheres by using systems of two coupled circulation cells. The present paper, however, focuses on the four-cell system, which provides a more accurate picture of the complex structure of the Sun’s meridional flow.
This latest approach allowed the researchers to describe changes of the solar plasma circulation intensity at the Sun’s different latitudes. The authors managed to relate the asymmetry of magnetic fields, observed in Solar Cycles 19-20 and 23-24, to the asymmetry of meridional flows in the northern and southern hemispheres.
In fact, it was assumed that each oscillator is coupled with only one other oscillator. Therefore, a system of four oscillators can be either a chain model or a ring model (see Figure 2). Solving the Kuramoto equations and studying the parameters of each oscillator helped identify the conditions under which they are synchronized and participate in massive transmissions of plasma flows as a single whole.
The research shows that the asymmetry between meridional oscillations in the Sun’s northern and southern hemispheres reveals itself for a long time and may be ascribed to the anomalies of the Sun’s magnetic field.
The researchers believe that in the solar dynamo model the role played by the meridional circulation in anomalous solar activity has not been sufficiently studied and deserves closer attention in the future.
See also:
Physicists from Russia and Brazil Unveil Mystery behind Complex Superconductor Patterns
Scientists at HSE MIEM and MIPT have demonstrated that highly complex spatial structures, similar to the intricate patterns found in nature, can emerge in superconductors. Mathematically, these patterns are described using the Ginzburg–Landau equation at a specific combination of parameters known as the Bogomolny point. The paper has been published in the Journal of Physics: Condensed Matter.
Adhesive Tape Helps Create Innovative THz Photodetector
An international team of researchers, including scientists at HSE University and Moscow Pedagogical State University (MPGU), has developed a novel photodetector composed of a thin superconducting film, capable of detecting weak terahertz (THz) radiation. This discovery holds promise for studying objects in space, developing wireless broadband communication systems, and making advancements in spectroscopy. The study has been published in Nano Letters.
Operation of Cellular Networks Found Similar to Bacteria Growth in Petri Dish
Scientists at the HSE Laboratory for Computational Physics have developed a new model for analysing communication networks that can significantly enhance the speed of mobile communications. To achieve this, the researchers used computational physics methods and phase transition models. It turns out that the functioning of cellular networks is in many ways similar to the growth of surfaces in physics. The study was performed using the HPC cHARISMa cluster at HSE University. The study findings have been published in Frontiers in Physics.
The Saudi Arabian National Team, Medal Winners at the International Physics Olympiad, Trained at HSE University
At the recent International Physics Olympiad (IPhO 2024) in Iran, students from Saudi Arabia achieved the best results in their country's history, winning one silver and three bronze medals. The team from the Kingdom made their first visit to Russia to receive their final training at the HSE Faculty of Physics.
'I've Always Been Keen to Engage in Experiments and Operate Scientific Instruments'
During his early years at university, physicist Ivan Makhov worried that he might be dismissed, but today he is heading a study supported by a grant from the Russian Science Foundation. In this interview with the HSE Young Scientists project, he shares his work experience using a closed-loop cryostat, his dream of conversing with Einstein, and favourite location in his hometown of St Petersburg.
‘Two Interdisciplinary Research Centres Can Create New Synergy between Themselves’
In mid-June 2024, HSE University and the Joint Institute for Nuclear Research in Dubna held a joint working meeting. This meeting was the first under an agreement signed by the research centres in 2024, when HSE University and JINR agreed to jointly participate in experiments of the NICA megascience project, as well as interact in the field of theoretical and mathematical physics, information technology, and personnel training. These issues were the focus of the first working meeting. Details are in the JINR report.
‘I Aspire to Make a Contribution Comparable to Prometheus' Gift to Humanity'
Egor Sedov initially planned to pursue a career in programming but instead became captivated by experimental physics. In this interview with the HSE Young Scientists project, he spoke about the quantum effect and the quantum standard, a scientist's letter from the future, and the magnetic levitation of a frog.
Russian Scientists Pioneer Accurate Mathematical Description of Quantum Dicke Battery
Physicists at HSE University and NUST MISIS have formulated and solved equations for a quantum battery, a device capable of storing energy in the form of light. Their findings will facilitate precise calculations of the capacity, power, and duration required for optimal battery charging. Quantum batteries are expected to improve the performance of solar panels and electric vehicles, while also opening up new avenues for efficient energy transfer. The study has been published in Physical Review A.
Scientists Harness 'Liquid Light' to Induce Electric Current in Superconductors
Scientists at HSE MIEM have induced a superconducting current using 'liquid light,' or excitonic polaritons, which are hybrid particles formed by interaction between light and matter and possess the properties of both light and material particles. The ability to manipulate an electrical system through an optical one can be valuable in the development of technologies such as quantum computers. The study has been published in Physical Review B.
Physicists Explain Transition Between Different Types of Superconductivity
Physicists from HSE MIEM in collaboration with colleagues from MIPT and other universities have formulated a theory capable of explaining the transition between different superconductivity types, revealing an intertype regime characterised by exotic magnetic properties. This discovery can serve as the foundation for the development of sensors with enhanced sensitivity and accuracy, capable of functioning in conditions where traditional sensors are less effective. The study has been published in Communications Physics.