K(1690) signal from COMPASS as a strange hybrid state
Abstract
A pseudoscalar resonance structure, denoted as the K(1690), was recently discovered by the COMPASS Collaboration in the scattering reaction K-+p→ K-π-π++p. If the K(1690) is a genuine state, there are three observed pseudoscalar strange mesons, namely the K(1460), K(1690), and K(1830), in the 1.0−2.0 GeV region. However, within the conventional quark model, only the 21S0 and 31S0 strange meson states are expected in this energy region. Therefore, at least one of these states should be interpreted as an exotic candidate. In this work, we study the spectrum of strange mesons systematically, and find that the K(1460) and K(1830) are good candidates of 21S0 and 31S0 strange mesons, respectively. A further investigation of their strong decays also supports this assignment. Furthermore, we note that the production mechanism of the K(1690) is similar to that of the π1(1600), which has been widely regarded as a hybrid meson candidate. We investigate the strong decays of the K(1690) within a constituent gluon model by treating it as a 0- strange hybrid meson and find that the results support the K(1690) as a hybrid state. Finally, we identify several important decay modes of the K(1690) that may be used in future experiments to test whether it contains the n1S0 (n=2 and 3) sq̅ component. We also suggest BESIII to search for the K(1690) state through the J/ψ→ K K(1690) → KK∗0(1430)π→ KKππ process.
Versions
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BibTeX
@misc{chen2026k1690,
title = {{$K(1690)$ signal from COMPASS as a strange hybrid state}},
author = {Bing Chen and Ri-Qing Qian and Xiang Liu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2607.20825},
eprint = {2607.20825},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2607.20825},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - K(1690) signal from COMPASS as a strange hybrid state
AU - Bing Chen
AU - Ri-Qing Qian
AU - Xiang Liu
PY - 2026
DA - 2026/09/15
PB - arXiv
DO - 10.48550/arxiv.2607.20825
UR - https://arxiv.org/abs/2607.20825
AB - A pseudoscalar resonance structure, denoted as the K(1690), was recently discovered by the COMPASS Collaboration in the scattering reaction K^-+p→ K^-π^-π^++p. If the K(1690) is a genuine state, there are three observed pseudoscalar strange mesons, namely the K(1460), K(1690), and K(1830), in the 1.0−2.0 GeV region. However, within the conventional quark model, only the 2^1S_0 and 3^1S_0 strange meson states are expected in this energy region. Therefore, at least one of these states should be interpreted as an exotic candidate. In this work, we study the spectrum of strange mesons systematically, and find that the K(1460) and K(1830) are good candidates of 2^1S_0 and 3^1S_0 strange mesons, respectively. A further investigation of their strong decays also supports this assignment. Furthermore, we note that the production mechanism of the K(1690) is similar to that of the π_1(1600), which has been widely regarded as a hybrid meson candidate. We investigate the strong decays of the K(1690) within a constituent gluon model by treating it as a 0^- strange hybrid meson and find that the results support the K(1690) as a hybrid state. Finally, we identify several important decay modes of the K(1690) that may be used in future experiments to test whether it contains the n^1S_0 (n=2 and 3) sq̅ component. We also suggest BESIII to search for the K(1690) state through the J/ψ→ K K(1690) → KK^∗_0(1430)π→ KKππ process.
ER -