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The B_{s}^{0}π^{±} invariant mass distribution is investigated in order to search for possible exotic meson states. The analysis is based on a data sample recorded with the LHCb detector corresponding to 3 fb^{-1} of pp collision data at sqrt[s]=7 and 8 TeV. No significant excess is found, and upper limits are set on the production rate of the claimed X(5568) state within the LHCb acceptance. Upper limits are also set as a function of the mass and width of a possible exotic meson decaying to the B_{s}^{0}π^{±} final state. The same limits also apply to a possible exotic meson decaying through the chain B_{s}^{*0}π^{±}, B_{s}^{*0}→B_{s}^{0}γ where the photon is excluded from the reconstructed decays.
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http://dx.doi.org/10.1103/PhysRevLett.117.152003 | DOI Listing |
Despite the f(980) hadron having been discovered half a century ago, the question about its quark content has not been settled: it might be an ordinary quark-antiquark ( ) meson, a tetraquark ( ) exotic state, a kaon-antikaon ( ) molecule, or a quark-antiquark-gluon ( ) hybrid. This paper reports strong evidence that the f(980) state is an ordinary meson, inferred from the scaling of elliptic anisotropies (v) with the number of constituent quarks (n), as empirically established using conventional hadrons in relativistic heavy ion collisions. The f(980) state is reconstructed via its dominant decay channel f(980) → ππ, in proton-lead collisions recorded by the CMS experiment at the LHC, and its v is measured as a function of transverse momentum (p).
View Article and Find Full Text PDFSci Bull (Beijing)
June 2025
School of Physics, Beihang University, Beijing 102206, China; Sino-French Carbon Neutrality Research Center, École Centrale de Pékin/School of General Engineering, Beihang University, Beijing 100191, China; Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beiji
The Λ(1405) has been one of the most controversial exotic baryons. If the Λ(1405) possesses a two-pole molecular structure, these poles are expected to evolve differently towards the SU(3) limit. From an analysis of a recent LQCD simulation on the πΣ-K‾N scattering for I=0 and the study of the quark mass dependence of the octet baryon masses, we determine for the first time the trajectories of these poles towards the symmetric point over the Tr[M]=C trajectory accurately.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA.
The spin-exotic hybrid meson π_{1}(1600) is predicted to have a large decay rate to the ωππ final state. Using 76.6 pb^{-1} of data collected with the GlueX detector, we measure the cross sections for the reactions γp→ωπ^{+}π^{-}p, γp→ωπ^{0}π^{0}p, and γp→ωπ^{-}π^{0}Δ^{++} in the range E_{γ}=8-10 GeV.
View Article and Find Full Text PDFPhys Rev Lett
September 2024
LAPTh, Université Savoie Mont-Blanc et CNRS, 74941 Annecy, France.
The duration of the neutrino burst from the supernova event SN 1987A is known to be sensitive to exotic sources of cooling, such as axions radiated from the dense and hot hadronic matter thought to constitute the inner core of the supernova. We perform the first quantitative study of the role of hadronic matter beyond the first generation--in particular strange matter. We do so by consistently including the full baryon and meson octets, and computing axion emissivity induced from baryon-meson to baryon-axion scatterings as well as from baryon decays.
View Article and Find Full Text PDFPhys Rev Lett
May 2024
Department of Theoretical Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India.
We report a lattice QCD study of the heavy-light meson-meson interactions with an explicitly exotic flavor content bcu[over ¯]d[over ¯], isospin I=0, and axial-vector J^{P}=1^{+} quantum numbers in search of possible tetraquark bound states. The calculation is performed at four values of lattice spacing, ranging from ∼0.058 to ∼0.
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