Publicação
Study of the $B_c^+ \rightarrow J/\psi D_s^+$ and $B_c^+ \rightarrow J/\psi D_s^{*+}$ decays with the ATLAS detector
| dc.contributor.author | ATLAS collaboration (2836 authors) | |
| dc.contributor.author | Aguilar-Saavedra, Juan Antonio | |
| dc.contributor.author | Amor Dos Santos, Susana Patricia | |
| dc.contributor.author | Anjos, Nuno | |
| dc.contributor.author | Araque, Juan Pedro | |
| dc.contributor.author | Cantrill, Robert | |
| dc.contributor.author | Carvalho, João | |
| dc.contributor.author | Castro, Nuno Filipe | |
| dc.contributor.author | Conde Muiño, Patricia | |
| dc.contributor.author | Da Cunha Sargedas De Sousa, Mario Jose | |
| dc.contributor.author | Fiolhais, Miguel | |
| dc.contributor.author | Galhardo, Bruno | |
| dc.contributor.author | Gomes, Agostinho | |
| dc.contributor.author | Gonçalo, Ricardo | |
| dc.contributor.author | Jorge, Pedro | |
| dc.contributor.author | Lopes, Lourenco | |
| dc.contributor.author | Machado Miguens, Joana | |
| dc.contributor.author | Maio, Amélia | |
| dc.contributor.author | Maneira, José | |
| dc.contributor.author | Onofre, António | |
| dc.contributor.author | Palma, Alberto | |
| dc.contributor.author | Pedro, Rute | |
| dc.contributor.author | Pina, João Antonio | |
| dc.contributor.author | Pinto, Belmiro | |
| dc.contributor.author | Santos, Helena | |
| dc.contributor.author | Saraiva, João | |
| dc.contributor.author | Silva, José | |
| dc.contributor.author | Tavares Delgado, Ademar | |
| dc.contributor.author | Veloso, Filipe | |
| dc.contributor.author | Wolters, Helmut | |
| dc.date.accessioned | 2019-02-04T07:31:08Z | |
| dc.date.available | 2019-02-04T07:31:08Z | |
| dc.date.issued | 2016-01-05 | |
| dc.date.updated | 2019-02-04T07:31:08Z | |
| dc.description.abstract | The decays $B_c^+ \rightarrow J/\psi D_s^+$ and $B_c^+ \rightarrow J/\psi D_s^{*+}$ are studied with the ATLAS detector at the LHC using a dataset corresponding to integrated luminosities of 4.9 and 20.6 fb$^{-1}$ of pp collisions collected at centre-of-mass energies $\sqrt{s} = 7$ TeV and 8 TeV, respectively. Signal candidates are identified through $J/\psi \rightarrow \mu ^+\mu ^-$ and $D_s^{(*)+}\rightarrow \phi \pi ^+(\gamma /\pi ^0)$ decays. With a two-dimensional likelihood fit involving the $B_c^+$ reconstructed invariant mass and an angle between the $\mu ^+$ and $D_s^+$ candidate momenta in the muon pair rest frame, the yields of $B_c^+ \rightarrow J/\psi D_s^+$ and $B_c^+ \rightarrow J/\psi D_s^{*+}$ , and the transverse polarisation fraction in $B_c^+ \rightarrow J/\psi D_s^{*+}$ decay are measured. The transverse polarisation fraction is determined to be $\Gamma _{\pm \pm }(B_c^+ \rightarrow J/\psi D_s^{*+})/\Gamma (B_c^+ \rightarrow J/\psi D_s^{*+}) = 0.38 \pm 0.23 \pm 0.07$ , and the derived ratio of the branching fractions of the two modes is $\mathcal {B}_{B_c^+ \rightarrow J/\psi D_s^{*+}}/\mathcal {B}_{B_c^+ \rightarrow J/\psi D_s^+} = 2.8 \,^{+1.2-0.8} \pm 0.3$ , where the first error is statistical and the second is systematic. Finally, a sample of $B_c^+\rightarrow J/\psi \pi ^+$ decays is used to derive the ratios of branching fractions $\mathcal {B}_{B_c^+ \rightarrow J/\psi D_s^+}/\mathcal {B}_{B_c^+ \rightarrow J/\psi \pi ^+} = 3.8 \pm 1.1 \pm 0.4 \pm 0.2$ and $\mathcal {B}_{B_c^+ \rightarrow J/\psi D_s^{*+}}/\mathcal {B}_{B_c^+ \rightarrow J/\psi \pi ^+} = 10.4 \pm 3.1 \pm 1.5 \pm 0.6$ , where the third error corresponds to the uncertainty of the branching fraction of $D_s^+\rightarrow \phi (K^+K^-)\pi ^+$ decay. The available theoretical predictions are generally consistent with the measurement. | |
| dc.description.version | Peer Reviewed | |
| dc.identifier | Eur.Phys.J. C76 (2016) 4; DOI 10.1140/epjc/s10052-015-3743-8 | |
| dc.identifier.uri | http://dx.doi.org/10.1140/epjc/s10052-015-3743-8 | |
| dc.identifier.uri | http://hdl.handle.net/10400.26/26890 | |
| dc.language.iso | eng | |
| dc.title | Study of the $B_c^+ \rightarrow J/\psi D_s^+$ and $B_c^+ \rightarrow J/\psi D_s^{*+}$ decays with the ATLAS detector | |
| dc.type | journal article | |
| dspace.entity.type | Publication | |
| rcaap.rights | openAccess | pt |
| rcaap.type | article |