• Physics 14, s124
The first outcomes from the Jinping Underground Nuclear Astrophysics particle accelerator refine a key response charge for the destruction of fluorine in stars.
The origin of fluorine is puzzling. The element is absent in the main nuclear reactions in stars, making it hard to figure out how it is formed. Fluorine is also easily destroyed by run-ins with protons and helium nuclei, destructive reactions whose contributions to fluorine’s lifecycle have yet to be pinned down because of difficulties in measuring the requisite reaction rates. A new particle accelerator in China could help in solving that problem, as its first results provide sharply reduced uncertainties in one fluorine reaction, fluorine atoms and protons convert to oxygen and helium atoms and gamma rays . While lots of the particulars of fluorine’s origin and destiny stay a thriller, these new response charges will assist refine ongoing calculations of this factor’s abundance within the cosmos.
The Jinping Underground Nuclear Astrophysics (JUNA) experimental facility is a latest addition to the deepest operational particle physics lab on the earth. Sitting beneath 2400 meters of rock, JUNA’s accelerator is effectively shielded from the cosmic rays which have hindered different makes an attempt to immediately measure a specific transformation of fluorine to oxygen on the proton energies related to the interiors of stars.
For their inaugural experiment, researchers bombarded two fluorine targets with proton beams that had energies as a low as 76.2 keV—an unprecedently small worth—and recorded the following bathe of gamma rays. From these measurements, they calculated that fluorine converts to oxygen through this response channel at a charge starting from
relying on the response temperature. Over the temperature vary of curiosity to astrophysics, the error within the measurements was beneath 10%, down from orders of magnitude, due to the ultralow cosmic-ray background and excessive depth of the proton beam.
Christopher Crockett is a contract author primarily based in Arlington, Virginia.
- L. Y. Zhang et al., “Direct measurement of the astrophysical
reaction in the deepest operational underground laboratory,” Phys. Rev. Lett. 127, 152702 (2021).