Measurement of B${}_{\mathrm{c}}$(2S)${}^{+}$ and B${}_{\mathrm{c}}^{\ast }$(2S)${}^{+}$ cross section ratios in proton-proton collisions at $\sqrt{s}=$ 13 TeV

Abstract

The ratios of the B${}_{\mathrm{c}}$(2S)${}^{+}$ to B${}_{\mathrm{c}}^{+}$, B${}_{\mathrm{c}}^{\ast }$(2S)${}^{+}$ to B${}_{\mathrm{c}}^{+}$, and B${}_{\mathrm{c}}^{\ast }$(2S)${}^{+}$ to B${}_{\mathrm{c}}$(2S)${}^{+}$ production cross sections are measured in proton-proton collisions at $\sqrt{s}=$ 13 TeV, using a data sample collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 143 fb${}^{-1}$. The three measurements are made in the B${}_{\mathrm{c}}^{+}$ meson phase space region defined by the transverse momentum $p_{\mathrm{T}}$ $>$ 15 GeV and absolute rapidity $|y|$ $<$ 2.4, with the excited B${}_{\mathrm{c}}^{(\ast )}$(2S)${}^{+}$ states reconstructed through the B${}_{\mathrm{c}}^{(\ast )+}{\pi }^{+}{\pi }^{-}$, followed by the B${}_{\mathrm{c}}^{+}$ $\to$ J/$\psi {\pi }^{+}$ and J/$\psi$ $\to$ ${\mu }^{+}{\mu }^{-}$ decays. The B${}_{\mathrm{c}}$(2S)${}^{+}$ to B${}_{\mathrm{c}}^{+}$, B${}_{\mathrm{c}}^{\ast }$(2S)${}^{+}$ to B${}_{\mathrm{c}}^{+}$, and B${}_{\mathrm{c}}^{\ast }$(2S)${}^{+}$ to B${}_{\mathrm{c}}$(2S)${}^{+}$ cross section ratios, including the unknown B${}_{\mathrm{c}}^{(\ast )}$(2S)${}^{+}$ $\to$ B${}_{\mathrm{c}}^{(\ast )+}{\pi }^{+}{\pi }^{-}$ branching fractions, are (3.47 $\pm$ 0.63 (stat) $\pm$ 0.33 (syst))%, (4.69 $\pm$ 0.71 (stat) $\pm$ 0.56 (syst))%, and 1.35 $\pm$ 0.32 (stat) $\pm$ 0.09 (syst), respectively. None of these ratios shows a significant dependence on the $p_{\mathrm{T}}$ or $|y|$ of the B${}_{\mathrm{c}}$ meson. The normalized dipion invariant mass distributions from the decays B${}_{\mathrm{c}}^{(\ast )}$(2S)${}^{+}$ $\to$ B${}_{\mathrm{c}}^{(\ast )}$${}^{+}{\pi }^{+}{\pi }^{-}$ are also reported.

Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/BPH-19-001 (CMS Public Pages)

References in corpus (6)

• An Introduction to PYTHIA 8.2
• The CMS trigger system
• Description and performance of track and primary-vertex reconstruction with the CMS tracker
• Observation of two excited B${}_{\mathrm{c}}^{+}$ states and measurement of the B${}_{\mathrm{c}}^{+}$(2S) mass in pp collisions at $\sqrt{s}=$ 13 TeV
• Mesons with Beauty and Charm: New Horizons in Spectroscopy
• Observation of an excited $B_c^{+}$ state

Cited by in corpus (7)

• $B_c$ meson spectroscopy motivated by general features of pNRQCD
• The role of multi-parton interactions in doubly-heavy hadron production
• Observation of the ${\Xi }_{\mathrm{b}}^{-}$ $\to$ $\psi$(2S)${\Xi }^{-}$ decay and studies of the ${\Xi }_{\mathrm{b}}$(5945)${}^0$ baryon in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Production of $D$-wave states of $\bar{b}c$ quarkonium at the LHC
• Heavy flavour production and spectroscopy
• Chromopolarizability of charm-beauty quarkonium from $B_c(2S)\to B_c\pi \pi$ transition
• Study of the two-body nonleptonic $B_c(2S)$ weak decays with the QCD factorization approach