Abstract
The newly observed $X(2100)$ by the BESIII Collaboration inspires our interest in studying the light meson system, especially axial-vector mesons. Since the $X(2100)$ has $J^P=1^+$ possibilities but cannot be distinguished only by mass, we make use of flux-tube model to study the strong decay behavior of $X(2100)$ under this assignment. The experimental width of the newly reported $X(2100)$ can be reproduced in our calculation, which favors an assignment of $X(2100)$ as the second radial excitation of $h_1(1380)$ with $I(J^P)=0(1^+)$. And the $\mathcal{B}(X(2100)\to \phi \eta^\prime)$ has a sizable contribution to the total width. Furthermore, we focus on the production of $X(2100)$ and its flavour partner $h_1(1965)$ induced by pion and kaon on a proton target with the Feynman model and the Regge model, which is an available platform to further identify their nature. The numerical results indicate that the total cross section are similar in the two models. When the range of momentum ${\mathrm{p_{Lab}}}$ is 10 to 30 GeV/$c$, the total cross sections for $\pi^-p\to X(2100)n$ and $K^-p\to X(2100)\Lambda$ are predicted to be at an order of magnitude of 0.1 $\mu$b. Whereas, the total cross section for $\pi^-p\to h_1(1965)n$ is near an order of magnitude of 10 $\mu$b when $p_{\mathrm{Lab}}$ is from 10 to 30 GeV/$c$, and much larger than that of reaction $K^-p\to h_1(1965)\Lambda$. These predictions can provide some valuable information to search for $X(2100)$ and $h_1(1965)$ in experiments at J-PARC, COMPASS, OKA@U-70 and SPS@CERN.
Highlights
Since 2003, a series of light flavor XYZ states have been observed, which include Xð1835Þ in J=ψ → γη0πþπ− [1,2], Xð1860Þ in J=ψ → γpp [3], Xð1812Þ in J=ψ → γωφ [4], Yð2175Þ in J=ψ → ηφf0ð980Þ [5,6], and so on
Our results show that h1ð1965Þ may decay into ηω which has comparable branching fraction with that of η0ω, i.e., We suggest BESIII to carry out the study of J=ψ → ηh1ð1965Þ → ηη0ω and ηηω, especially by checking the corresponding ωη and ωη0 invariant mass spectra
Through the analysis of the mass, we find that there exist two assignments to Xð2100Þ, i.e., Xð2100Þ can be the second radial excitation of h1 family or the second radial excitation of isoscalar vector states
Summary
Since 2003, a series of light flavor XYZ states have been observed, which include Xð1835Þ in J=ψ → γη0πþπ− [1,2], Xð1860Þ in J=ψ → γpp [3], Xð1812Þ in J=ψ → γωφ [4], Yð2175Þ in J=ψ → ηφf0ð980Þ [5,6], and so on. Radial excitation of h1ð1380Þ, h1ð2120Þ was predicted, whose resonance parameter is consistent with the BESIII’s measurement listed in Eq (2) This fact makes us conjecture that this structure existing in the φη0 invariant mass spectrum of the J=ψ → φηη0 decay [24] should be a good candidate of higher state in the h1 meson family. The obtained partial decay widths of Xð2100Þ can be applied to extract the corresponding coupling constants, which will be input parameters when calculating the cross section of these discussed production processes.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
