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New LHCb pentaquarks as hadrocharmonium states

New LHCb Collaboration results on pentaquarks with hidden charm [1] are discussed. These results fit nicely in the hadrocharmonium pentaquark scenario [2,3]. In the new data the old LHCb pentaquark $P_c(4450)$ splits into two states $P_c(4440)$ and $P_c(4457)$. We interpret these two almost degenera...

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Autores principales: Eides, Michael I., Petrov, Victor Yu, Polyakov, Maxim V.
Lenguaje:eng
Publicado: 2019
Materias:
Acceso en línea:https://dx.doi.org/10.1142/S0217732320501515
http://cds.cern.ch/record/2759246
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author Eides, Michael I.
Petrov, Victor Yu
Polyakov, Maxim V.
author_facet Eides, Michael I.
Petrov, Victor Yu
Polyakov, Maxim V.
author_sort Eides, Michael I.
collection CERN
description New LHCb Collaboration results on pentaquarks with hidden charm [1] are discussed. These results fit nicely in the hadrocharmonium pentaquark scenario [2,3]. In the new data the old LHCb pentaquark $P_c(4450)$ splits into two states $P_c(4440)$ and $P_c(4457)$. We interpret these two almost degenerate hadrocharmonium states with $J^P=1/2^-$ and $J^P=3/2^-$ as a result of hyperfine splitting between hadrocharmonium states predicted in [2]. It arises due to QCD multipole interaction between color-singlet hadrocharmonium constituents. We improve the theoretical estimate of hyperfine splitting [2,3] that is compatible with the experimental data. The new $P_c(4312)$ state finds a natural explanation as a bound state of $\chi_{c0}$ and a nucleon, with $I=1/2$, $J^P=1/2^+$ and binding energy 42 MeV. As a bound state of a spin-zero meson and a nucleon, hadrocharmonium pentaquark $P_c(4312)$ does not experience hyperfine splitting. We find a series of hadrocharmonium states in the vicinity of the wide $P_c(4380)$ pentaquark that can explain its apparently large decay width. We compare the hadrocharmonium and molecular pentaquark scenarios and discuss their relative advantages and drawbacks.
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spelling cern-27592462021-03-29T02:08:32Zdoi:10.1142/S0217732320501515http://cds.cern.ch/record/2759246engEides, Michael I.Petrov, Victor YuPolyakov, Maxim V.New LHCb pentaquarks as hadrocharmonium stateshep-phParticle Physics - PhenomenologyNew LHCb Collaboration results on pentaquarks with hidden charm [1] are discussed. These results fit nicely in the hadrocharmonium pentaquark scenario [2,3]. In the new data the old LHCb pentaquark $P_c(4450)$ splits into two states $P_c(4440)$ and $P_c(4457)$. We interpret these two almost degenerate hadrocharmonium states with $J^P=1/2^-$ and $J^P=3/2^-$ as a result of hyperfine splitting between hadrocharmonium states predicted in [2]. It arises due to QCD multipole interaction between color-singlet hadrocharmonium constituents. We improve the theoretical estimate of hyperfine splitting [2,3] that is compatible with the experimental data. The new $P_c(4312)$ state finds a natural explanation as a bound state of $\chi_{c0}$ and a nucleon, with $I=1/2$, $J^P=1/2^+$ and binding energy 42 MeV. As a bound state of a spin-zero meson and a nucleon, hadrocharmonium pentaquark $P_c(4312)$ does not experience hyperfine splitting. We find a series of hadrocharmonium states in the vicinity of the wide $P_c(4380)$ pentaquark that can explain its apparently large decay width. We compare the hadrocharmonium and molecular pentaquark scenarios and discuss their relative advantages and drawbacks.New LHCb Collaboration results on pentaquarks with hidden charm1 are discussed. These results fit nicely in the hadrocharmonium pentaquark scenario.2,3, In the new data the old LHCb pentaquark Pc(4450) splits into two states Pc(4440) and Pc(4457). We interpret these two almost degenerated hadrocharmonium states with JP = 1/2− and JP = 3/2−, as a result of hyperfine splitting between hadrocharmonium states predicted in Ref. 2. It arises due to QCD multipole interaction between color-singlet hadrocharmonium constituents. We improve the theoretical estimate of hyperfine splitting2,3 that is compatible with the experimental data. The new Pc(4312) state finds a natural explanation as a bound state of χc0 and a nucleon, with I = 1/2, JP = 1/2+ and binding energy 42 MeV. As a bound state of a spin-0 meson and a nucleon, hadrocharmonium pentaquark Pc(4312) does not experience hyperfine splitting. We find a series of hadrocharmonium states in the vicinity of the wide Pc(4380) pentaquark that can explain its apparently large decay width. We compare the hadrocharmonium and molecular pentaquark scenarios and discuss their relative advantages and drawbacks.arXiv:1904.11616oai:cds.cern.ch:27592462019-04-25
spellingShingle hep-ph
Particle Physics - Phenomenology
Eides, Michael I.
Petrov, Victor Yu
Polyakov, Maxim V.
New LHCb pentaquarks as hadrocharmonium states
title New LHCb pentaquarks as hadrocharmonium states
title_full New LHCb pentaquarks as hadrocharmonium states
title_fullStr New LHCb pentaquarks as hadrocharmonium states
title_full_unstemmed New LHCb pentaquarks as hadrocharmonium states
title_short New LHCb pentaquarks as hadrocharmonium states
title_sort new lhcb pentaquarks as hadrocharmonium states
topic hep-ph
Particle Physics - Phenomenology
url https://dx.doi.org/10.1142/S0217732320501515
http://cds.cern.ch/record/2759246
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AT petrovvictoryu newlhcbpentaquarksashadrocharmoniumstates
AT polyakovmaximv newlhcbpentaquarksashadrocharmoniumstates