A structure is observed in the ±∓ mass spectrum in a sample of proton–proton collisions at centre-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of 9fb−1. The structure is interpreted as the result of overlapping excited 0 states. With high significance, a two-peak hypothesis provides a better description of the data than a single resonance. Under this hypothesis the masses and widths of the two states, assuming they decay directly to ±∓, are determined to be1Γ12Γ2=6063.5±1.2 (stat)±0.8 (syst)MeV,=26±4 (stat)±4 (syst)MeV,=6114±3 (stat)±5 (syst)MeV,=66±18 (stat)±21 (syst)MeV.Alternative values assuming a decay through ∗±∓, with a missing photon from the ∗±→± decay, which are shifted by approximately 45MeV, are also determined. The possibility of a single state decaying in both channels is also considered. The ratio of the total production cross-section times branching fraction of the new states relative to the previously observed ∗02 state is determined to be 0.87±0.15 (stat)±0.19 (syst).

Observation of new excited Bs0 states / Aaij, R., Beteta, C.A., Ackernley, T., Adeva, B., Adinolfi, M., Afsharnia, H., Aidala, C.A., Aiola, S., Ajaltouni, Z., Akar, S., Albrecht, J., Alessio, F., Alexander, M., Albero, A.A., Aliouche, Z., Alkhazov, G., Cartelle, P.A., Amato, S., Amhis, Y., An, L., et al.. - In: THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS. - ISSN 1434-6044. - 81:7(2021). [10.1140/epjc/s10052-021-09305-3]

Observation of new excited Bs0 states

Capriotti, L.;Casse, G.;Sarti, A.;Sciubba, A.;
2021

Abstract

A structure is observed in the ±∓ mass spectrum in a sample of proton–proton collisions at centre-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of 9fb−1. The structure is interpreted as the result of overlapping excited 0 states. With high significance, a two-peak hypothesis provides a better description of the data than a single resonance. Under this hypothesis the masses and widths of the two states, assuming they decay directly to ±∓, are determined to be1Γ12Γ2=6063.5±1.2 (stat)±0.8 (syst)MeV,=26±4 (stat)±4 (syst)MeV,=6114±3 (stat)±5 (syst)MeV,=66±18 (stat)±21 (syst)MeV.Alternative values assuming a decay through ∗±∓, with a missing photon from the ∗±→± decay, which are shifted by approximately 45MeV, are also determined. The possibility of a single state decaying in both channels is also considered. The ratio of the total production cross-section times branching fraction of the new states relative to the previously observed ∗02 state is determined to be 0.87±0.15 (stat)±0.19 (syst).
2021
B physics; branching fraction; flavor physics; Hadron-Hadron scattering (experiments)
01 Pubblicazione su rivista::01a Articolo in rivista
Observation of new excited Bs0 states / Aaij, R., Beteta, C.A., Ackernley, T., Adeva, B., Adinolfi, M., Afsharnia, H., Aidala, C.A., Aiola, S., Ajaltouni, Z., Akar, S., Albrecht, J., Alessio, F., Alexander, M., Albero, A.A., Aliouche, Z., Alkhazov, G., Cartelle, P.A., Amato, S., Amhis, Y., An, L., et al.. - In: THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS. - ISSN 1434-6044. - 81:7(2021). [10.1140/epjc/s10052-021-09305-3]
File allegati a questo prodotto
File Dimensione Formato  
LHCb Collaboration_observation_2021.pdf

accesso aperto

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Creative commons
Dimensione 963.54 kB
Formato Adobe PDF
963.54 kB Adobe PDF

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/11573/1580088
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 20
  • ???jsp.display-item.citation.isi??? 18
social impact