A team of scientists has provided the first observational evidence that a specific type of young star is capable of emitting gamma rays.
The highly energetic radiation from space is not easily observed from Earth. Use Fermi satellite With high sensitivity, scientists can solve this problem by studying the universe gamma rays, the most active region of the electromagnetic spectrum. The Fermi satellite has been observing the sky continuously since its launch in 2008, and from these observations it has been determined that approximately 30% of the gamma-ray sources detected in the entire night sky remain unknown – the origin of these gamma-ray detections is unknown.
Doctoral student Agustina Velokomo and her team of scientists set out to study some of the mysterious sources of gamma rays in order to determine their origin. It was noted that several sources of gamma rays appeared to originate from regions where new stars are forming, but the team had no explanation for this phenomenon and decided to investigate it further. The study focuses on the star formation region NGC 2071Which is located in the northern part The Orion b molecular cloud.
To investigate the mysterious cause gamma ray burstsA team of scientists decided to focus on the things known as T-Tauri stars. T Tauri stars are low-mass stars that are forming. It consists of a central star and A disk of gas and dustWhere planets can form. T Tauri stars are notoriously variable in brightness and are usually found near regions of active star formation.
The team noted that three unidentified sources of gamma rays observed at different intervals originated in the part of the sky where the young star formation region of NGC 2071 is located. At least 58 stars categorized as T Tauri stars are known to form there. There are no other objects in this region that could be a source of gamma radiation emission.
One possible explanation is that occasional gamma-ray bursts are generated by T Tauri stars during massive outbursts called “massive flares.” In these electromagnetic bursts, magnetic energy stored in the stars’ atmospheres is released. Megaflares can span several stellar radii and last for several hours. It is worth noting that although there is currently flare activity on the Sun, it cannot be compared to massive flares. Huge flares are much more powerful, and if they occur on the Sun, they could be harmful to life on Earth.
This may explain the origin of many previously unknown sources of gamma rays. And by studying these physical processes in T Tauri stars, we can also learn about the early conditions that shaped the Sun and our planet. Solar System.
PhD student Agustina Velokomo says: This observational evidence is essential to understanding the origin of previously unknown sources for more than a decade, and is undoubtedly a step forward in astronomy. It is also important to understand the processes involved in the early stages of star formation: if a T Tauri star produces gamma rays, it will affect the gas conditions in the protoplanetary disk and thus the evolution of planet formation. Discovering this phenomenon allows us to understand not only how the Sun formed and evolved, but also our home planet Earth.
Work remained published 23 September 2023, Monthly Notices of the Royal Astronomical Society.
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Agnes Nowak
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Source: Ras
Pictured: An artist’s impression of a T Tauri star: a system consisting of a central star and a protoplanetary disk. Source: INAF-OAPa/S. Orlando
