The study of a wide peaking structure in the Bc+ γ mass spectrum is reported using a data sample of proton-proton collisions collected by the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb^−1. The observed structure is consistent with the lowest excited P-wave Bc+ states and exhibits a statistical significance exceeding 7 standard deviations relative to the background-only hypothesis. A two-peak model serves as an effective description of the data, with various theory-constrained models further explored to provide physical interpretation. Based on the predictions for the Bc(1P)+ spectrum, the relative production cross-section of the overall Bc(1P)+ states with respect to the Bc+ ground state with the transverse momentum p_T and rapidity y of Bc+ mesons in the regions p_T < 20 GeV/c and 2.0 < y < 4.5 at √s = 13 TeV is measured to be 0.20 ± 0.03 ± 0.02 ± 0.03, where the uncertainty terms represent statistical, systematic, and uncertainties related to the choice of theoretical models, respectively. The results provide a test of theoretical models and deepen our understanding of quantum chromodynamics.

Aaij, R., Abdelmotteleb, A. s. w., Abellan Beteta, C., Abudinén, F., Ackernley, T., Adefisoye, A. a., et al. (2025). Study of Bc(1P)+ states in the Bc+ γ mass spectrum. PHYSICAL REVIEW D, 112(11), 1-18 [10.1103/1d49-q8h4].

Study of Bc(1P)+ states in the Bc+ γ mass spectrum

Carbone, A.;Ferrari, F.;Galli, D.;Patrignani, C.;Spedicato, E.;Zenesini, F.;
2025

Abstract

The study of a wide peaking structure in the Bc+ γ mass spectrum is reported using a data sample of proton-proton collisions collected by the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb^−1. The observed structure is consistent with the lowest excited P-wave Bc+ states and exhibits a statistical significance exceeding 7 standard deviations relative to the background-only hypothesis. A two-peak model serves as an effective description of the data, with various theory-constrained models further explored to provide physical interpretation. Based on the predictions for the Bc(1P)+ spectrum, the relative production cross-section of the overall Bc(1P)+ states with respect to the Bc+ ground state with the transverse momentum p_T and rapidity y of Bc+ mesons in the regions p_T < 20 GeV/c and 2.0 < y < 4.5 at √s = 13 TeV is measured to be 0.20 ± 0.03 ± 0.02 ± 0.03, where the uncertainty terms represent statistical, systematic, and uncertainties related to the choice of theoretical models, respectively. The results provide a test of theoretical models and deepen our understanding of quantum chromodynamics.
2025
Aaij, R., Abdelmotteleb, A. s. w., Abellan Beteta, C., Abudinén, F., Ackernley, T., Adefisoye, A. a., et al. (2025). Study of Bc(1P)+ states in the Bc+ γ mass spectrum. PHYSICAL REVIEW D, 112(11), 1-18 [10.1103/1d49-q8h4].
Aaij, R.; Abdelmotteleb, A.  s.  w.; Abellan Beteta, C.; Abudinén, F.; Ackernley, T.; Adefisoye, A.  a.; Adeva, B.; Adinolfi, M.; Adlarson, P.; Agapop...espandi
File in questo prodotto:
File Dimensione Formato  
2025-AR-59-Study_of_Bc1Pp_States-PRD.pdf

accesso aperto

Tipo: Versione (PDF) editoriale / Version Of Record
Licenza: Licenza per Accesso Aperto. Creative Commons Attribuzione (CCBY)
Dimensione 1.17 MB
Formato Adobe PDF
1.17 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/1036730
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 0
social impact