Shattered atomic nuclei: Unveiling of their mysterious shapes
Shattered atomic nuclei: Unveiling of their mysterious shapes
physicists have discovered a new method for examining the form of atomic nuclei-by destroying them in high energy collisions. This method could help scientists to better understand the forms of nuclei, which, for example, influences the education rate of elements in stars and helps to determine which materials are best suited as nuclear fuel.
"The shape of the kernels affects almost all aspects of the atomic nucleus and nuclear processes," says Jie Meng, a nuclear physicist at Beijing University in Beijing. The new imaging method published on November 6th in the Nature Journal represents "an important and exciting progress", says Meng.
A team at the relativistic heavy ion collider (RHIC) in the Brookhaven National Laboratory in Upton, New York, left two rays of uranium-238-and later two rays of gold-with extreme energies. They met "so violently that we practically melted the kernels in a soup," says co -author Jiangyong Jia, a physicist at Stony Brook University in New York.
The hot plasma generated by the collisions expanded very quickly under pressure, whereby this was connected to the initial form of the kernels. With a detector named Solenoidal Tracker at Rhic or Star, who recorded the impulse of several thousand particles that were generated by both types of collisions and compared the results with models, the team was able to "turn the clock back in order to derive the shape of the kernels, explains Jia.
Hidden figures
A atomic nucleus consists of protons and neutrons that occupy energy levels like electrons. In general, the particles take on a form that minimizes the energy of the system. Similar to a drop of water, the core can take different shapes, including that of a pear, American football or peanut shell. The shape of a core is "very difficult to predict," says Jia. You can also vary.
Previous experiments for researching the form consisted of distracting low -energy ions from the cores. This method-called Coulomb suggestion-stimulates the seeds, and the radiation that you emit while falling back to your basic state reveals aspects of your shape. Since the time measure is relatively long, this type of imaging can only show a long -term recording that shows the average of all form fluctuations.
In contrast, the high energy collision method provides an immediate image of the cores during the impact. It is a more direct method that makes you better suited for examining exotic forms, says Jia.The technology confirmed that gold had an almost spherical shape that was consistent from one picture to the next. In contrast, the uranium form in the snapshots changed when the kernels collided in different orientations. This made it possible for the researchers to calculate the relative lengths of the uranium core in three dimensions, which indicates that uranium is not only stretched, but also slightly compressed in a dimension, similar to a deflated American football.
"It is fascinating that it worked" and that other nuclear processes did not affect the emission of the particles and the deformation, Magdalena Zielińska, a nuclear physicist of the French agency for alternative energies and atomic energy near Paris.
hard or soft?
This type of imaging could help to manage the challenging task, to distinguish between cores that are 'rigid', that is, have well -defined forms, and 'soft' that fluctuates, says Zielińska.
Jia says his team also wants to use the method to examine the differences between light ions such as oxygen and neon. Oxygen core are almost spherical, while neon seeds - which also wear two protons and two neutrons - are bent. The comparison of their forms would enable researchers to understand how protons and neutron clusters form in the cores, according to Jia.
Information about the form can also show whether it is likely that nuclei interact with each other or go through a nuclear division and can increase the likelihood called Neutrino-Los β-decay to discover, which could help to solve a few long-cherished puzzles in physics. About 99.9% of visible matter is in the center of the atoms, says Jia. "Understanding the nuclear building block is practically the heart of understanding who we are."
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Star Collaboration Nature https://doi.org/10.1038/S41586-08097-2 (2024).