Particle physicists map charm quark production with record precision
Researchers at China's BEPCII collider have made the most precise measurements yet of how electron-positron collisions produce charm quarks—exotic particles that decay in microseconds. The findings resolve long-standing questions about mysterious resonance states and could refine models used in particle detector design and fundamental physics research.
Originaltitel: Precise Measurement of Born Cross Sections for <em>e</em><sup>+</sup><em>e</em><sup>-</sup> → <em>D</em><em>D<</em>over-bar> at √<em>s</em>=3.80-4.95 GeV
<p>Using data samples collected with the BESIII detector at the BEPCII collider at center-of-mass energies ranging from 3.80 to 4.95 GeV, corresponding to an integrated luminosity of 20 fb<sup>-1</sup>, a measurement of Born cross sections for the e<sup>+</sup>e<sup>-</sup> → D<sup>0</sup>D<sup>0</sup><over bar> and D<sup>+</sup>D<sup>-</sup> processes is presented with unprecedented precision. Many clear peaks in the line shape of e<sup>+</sup>e<sup>-</sup> → D<sup>0</sup>D<sup>0</sup><over bar> and D<sup>+</sup>D<sup>-</sup> around the mass range of G(3900), ψ(4040), ψ(4160), Y(4260), and ψ(4415), etc., are foreseen. These results offer crucial experimental insights into the nature of hadron production in the open-charm region.</p>