Physicists rule out exotic particle, narrowing the search for new matter
An international team found no evidence for a rare, short-lived particle called X(1870) in data from 10 billion collision events. The null result tightens constraints on particle physics models and helps researchers focus resources on more promising avenues for discovering new forms of matter that could reshape materials science and energy technology.
Originaltitel: Search for 𝑋(1870) via the decay 𝐽/𝜓 →𝜔𝐾+𝐾−𝜂
<p>Using a sample of (10087 ±44) ×106 𝐽/𝜓 events collected by the BESIII detector at the BEPCII collider, we search for the decay 𝑋(1870) →𝐾+𝐾−𝜂 via the 𝐽/𝜓 →𝜔𝐾+𝐾−𝜂 process for the first time. No significant 𝑋(1870) signal is observed. The upper limit on the branching fraction of the decay 𝐽/𝜓 →𝜔𝑋(1870) →𝜔𝐾+𝐾−𝜂 is determined to be 9.55 ×10<sup>−7</sup> at the 90% confidence level. In addition, the branching faction 𝐵(𝐽/𝜓 →𝜔𝐾+𝐾−𝜂) is measured to be (3.33 ±0.02(stat) ±0.12(syst)) ×10<sup>−4</sup>.</p>