The first observation of the B s 0 → η ′ η ′ decay is reported. The study is based on a sample of proton-proton collisions corresponding to 3.0 fb - 1 of integrated luminosity collected with the LHCb detector. The significance of the signal is 6.4 standard deviations. The branching fraction is measured to be [3.31 ± 0.64 (stat) ± 0.28 (syst) ± 0.12 (norm)] × 10 - 5, where the third uncertainty comes from the B ± → η ′ K ± branching fraction that is used as a normalization. In addition, the charge asymmetries of B ± → η ′ K ± and B ± → Φ K ±, which are control channels, are measured to be (- 0.2 ± 1.3) % and (+ 1.7 ± 1.3) %, respectively. All results are consistent with theoretical expectations.

Observation of the B-s(0) -> eta 'eta ' Decay

COGONI, VIOLETTA;Dettori, F.;MANCA, GIULIA;OLDEMAN, RUDOLF GERHARD CHRISTIAAN;SAITTA, BIAGIO;VACCA, CLAUDIA;
2015

Abstract

The first observation of the B s 0 → η ′ η ′ decay is reported. The study is based on a sample of proton-proton collisions corresponding to 3.0 fb - 1 of integrated luminosity collected with the LHCb detector. The significance of the signal is 6.4 standard deviations. The branching fraction is measured to be [3.31 ± 0.64 (stat) ± 0.28 (syst) ± 0.12 (norm)] × 10 - 5, where the third uncertainty comes from the B ± → η ′ K ± branching fraction that is used as a normalization. In addition, the charge asymmetries of B ± → η ′ K ± and B ± → Φ K ±, which are control channels, are measured to be (- 0.2 ± 1.3) % and (+ 1.7 ± 1.3) %, respectively. All results are consistent with theoretical expectations.
File in questo prodotto:
File Dimensione Formato  
PhysRevLett.115.051801.pdf

accesso aperto

Tipologia: versione editoriale
Dimensione 352.62 kB
Formato Adobe PDF
352.62 kB 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/11584/192504
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 10
  • ???jsp.display-item.citation.isi??? 9
social impact