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Exotic $T_{c \bar{s} 0}^{a} (2900)^{0}$ and $T_{c \bar{s} 0}^{a} (2900)^{+ +}$ states in the Born-Oppenheimer approximation

Department of Physics, Faculty of Science, Ondokuz Mayis University, 55200 Samsun, Türkiye

^*Contact author: hmutuk@omu.edu.tr

Phys. Rev. D 113, 034020 – Published 17 February, 2026

DOI: https://doi.org/10.1103/3z79-67zf

Abstract

We employ the Born-Oppenheimer approximation to the $T_{c \bar{s} 0}^{a} (2900)^{0}$ and $T_{c \bar{s} 0}^{a} (2900)^{+ +}$ states observed by the LHCb Collaboration and study mass spectrum and root-mean-square radius values. For this purpose, we use the dynamical diquark model. We assume that a strange quark is heavy for the usage of the Born-Oppenheimer approximation. Our results strongly indicate that the $T_{c \bar{s} 0}^{a} (2900)$ states are best described as composed of axial-vector (spin-1) diquark pairs. Furthermore, the calculated root-mean-square radius, $⟨ r^{2} ⟩^{1 / 2} \approx 0.70 - 0.80 fm$ , which is significantly less than 1 fm, provides compelling evidence that these are compact tetraquarks rather than loosely bound hadronic molecules.

Physics Subject Headings (PhySH)

Exotic mesons

Article Text

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Phys. Rev. D 113, 034020– Published 17 February, 2026

Vol. 113, Iss. 3 — 1 February 2026

Received 2 December 2025
Accepted 29 January 2026

DOI: https://doi.org/10.1103/3z79-67zf

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Exotic $T_{c \bar{s} 0}^{a} (2900)^{0}$ and $T_{c \bar{s} 0}^{a} (2900)^{+ +}$ states in the Born-Oppenheimer approximation

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Exotic Tcs¯0a(2900)0 and Tcs¯0a(2900)++ states in the Born-Oppenheimer approximation

Abstract

Physics Subject Headings (PhySH)

Article Text

References (55)

Exotic $T_{c \bar{s} 0}^{a} (2900)^{0}$ and $T_{c \bar{s} 0}^{a} (2900)^{+ +}$ states in the Born-Oppenheimer approximation