Observation of Ω Contribution in the c1(3872) → Π+π−j/ψ Decays

<p>Resonant structure in the dipion mass spectrum produced via \decay{\Bu}{\X\Kp}, \decay{\X}{\jpsi \pip \pim}, with \decay{\jpsi}{\mu^+\mu^-} is analyzed using Run 1 and Run 2 data samples from the LHCb experiment. The spectrum is dominated by \rhoz\toπ⁺π^-, but cannot be described by this contribution alone. A significant ω\toπ⁺π^- contribution, interfering with $\rhoz$, is observed for the first time. This is a more significant observation (>7.1σ) of \X\toω\jpsi decays, than previously achieved with ω\toπ⁺π^-π⁰ decays. The relative contribution of ω to the total \X\toπ⁺π^-\jpsi rate is at the level expected from the measured \X\to(ω\toπ⁺π^-π⁰)\jpsi rate, if the interference between the \rho⁰ and ω amplitudes is neglected, $(1.9\pm0.4\pm0.3)\%$. The interference enhances the importance of ω contribution by an order of magnitude to $(21.4\pm2.3\pm2.0)\%$. The results support interpretations of the $\X$ state as an exotic hadron, since its isospin violating $\rhoz\jpsi$ decay rate, relative to isospin conserving ω\jpsi decay, is an order of magnitude larger than expected for an ordinary charmonium state.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Year

2021

Author dc:creator

• Batsukh, Baasansuren

Contributors dc:contributor

• Skwarnicki, Tomasz

• Physical Sciences and Mathematics
• Physics

Repository record dc:identifier

https://surface.syr.edu/etd/1406

OAI identifier oai:identifier

oai:surface.syr.edu:etd-2407