Study of excited ${\Lambda }_{\mathrm{b}}^0$ states decaying to ${\Lambda }_{\mathrm{b}}^0{\pi }^{+}{\pi }^{-}$ in proton-proton collisions at $\sqrt{s}=$ 13 TeV

Abstract

A study of excited ${\Lambda }_{\mathrm{b}}^0$ baryons is reported, based on a data sample collected in 2016-2018 with the CMS detector at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of up to 140 fb${}^{-1}$. The existence of four excited ${\Lambda }_{\mathrm{b}}^0$ states: ${\Lambda }_{\mathrm{b}}$(5912)${}^0$, ${\Lambda }_{\mathrm{b}}$(5920)${}^0$, ${\Lambda }_{\mathrm{b}}$(6146)${}^0$, and ${\Lambda }_{\mathrm{b}}$(6152)${}^0$ in the ${\Lambda }_{\mathrm{b}}^0{\pi }^{+}{\pi }^{-}$ mass spectrum is confirmed, and their masses are measured. The ${\Lambda }_{\mathrm{b}}^0{\pi }^{+}{\pi }^{-}$ mass distribution exhibits a broad excess of events in the region of 6040-6100 MeV, whose origin cannot be discerned with the present data.

arXiv commentReplaced with the published version. Added the journal reference. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/BPH-19-003 (CMS Public Pages)

References in corpus (30)

• An Introduction to PYTHIA 8.2
• Asymptotic formulae for likelihood-based tests of new physics
• The CMS trigger system
• Description and performance of track and primary-vertex reconstruction with the CMS tracker
• Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
• Heavy Baryons in a Quark Model
• Masses of excited heavy baryons in the relativistic quark-diquark picture
• CMS Tracking Performance Results from early LHC Operation
• Faddeev study of heavy baryon spectroscopy
• Assignments of ${\Lambda }_Q$ and ${\Xi }_Q$ baryons in the heavy quark-light diquark picture
• Strong and radiative decays of the low-lying $S$- and $P$-wave singly heavy baryons
• The Quark Model and $b$ Baryons
• Observation of excited Lambda_b0 baryons
• 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
• Excited State Mass spectra and Regge trajectories of Bottom Baryons
• Odd parity bottom-flavored baryon resonances
• Heavy baryon spectroscopy in QCD
• Spectroscopy of singly, doubly, and triply bottom baryons
• Heavy quark symmetry in multi-hadron systems
• Observation of new resonances in the ${\Lambda }_b^0{\pi }^{+}{\pi }^{-}$ system
• Sensitivity of searches for new signals and its optimization
• Search for the X(5568) state decaying into ${\mathrm{B}}_{\mathrm{s}}^0{\pi }^{\pm }$ in proton-proton collisions at $\sqrt{s}=$ 8 TeV
• Study of beauty hadron decays into pairs of charm hadrons
• Evidence for a bottom baryon resonance Lambda_b* in CDF data
• Observation of a new baryon state in the ${\Lambda }_b^0{\pi }^{+}{\pi }^{-}$ mass spectrum
• Observation of the decays ${\Lambda }_b^0\to {\chi }_{c1}p{K}^{-}$ and ${\Lambda }_b^0\to {\chi }_{c2}p{K}^{-}$
• Single heavy baryons with chiral partner structure in a three-flavor chiral model
• Open bottom states and the anti-B meson propagation in hadronic matter
• Studies of B${}_{s2}^{\ast }(5840{)}^0$ and B${}_{s1}(5830{)}^0$ mesons including the observation of the B${}_{s2}^{\ast }(5840{)}^0\to$ B${}^0$K${}_{\mathrm{S}}^0$ decay in proton-proton collisions at $\sqrt{s}=$ 8 TeV
• Spectra of charmed and bottom baryons with hyperfine interaction

Cited by in corpus (28)

• An updated review of the new hadron states
• Observation of a new excited beauty strange baryon decaying to ${\Xi }_{\mathrm{b}}^{-}{\pi }^{+}{\pi }^{-}$
• Mass-spectra of singly, doubly, and triply bottom baryons
• Relativistic corrections to decays of heavy baryons in the quark model
• Radiative M1 transitions of heavy baryons: Effective Quark Mass Scheme
• $QQ\bar{s}\bar{s}$ tetraquarks in the chiral quark model
• Universal behavior of mass gaps existing in the single heavy baryon family
• Measurement of the ${\Lambda }_b^0\to J/\psi \Lambda$ angular distribution and the ${\Lambda }_b^0$ polarisation in $pp$ collisions
• Toward establishing the low-lying $P$-wave ${\Sigma }_b$ states
• Strong decays of the low-lying bottom strange baryons
• Roper-like resonances with various flavor contents and their two-pion emission decays
• Molecular ${\Omega }_{cc}$ , ${\Omega }_{bb}$ and ${\Omega }_{bc}$ states
• $b$-hadron spectroscopy study based on the similarity of double bottom baryon and bottom meson
• Spectra and decay properties of ${\Lambda }_b$ and ${\Sigma }_b$ baryons
• Analysis of the 1S and 2S states of the ${\Lambda }_Q$ and ${\Xi }_Q$ with the QCD sum rules
• ${\Lambda }_b(6146{)}^0$ state newly observed by LHCb
• Refining radiative decay studies in singly heavy baryons
• New ${\Lambda }_b(6072{)}^0$ state as a $2S$ bottom baryon
• 70 Years of Hyperon Spectroscopy: A review of strange $\Xi$, $\Omega$ baryons, and the spectrum of charmed and bottom baryons
• Three-body decay of ${\Lambda }_c^{\ast }(2765)$ and determination of its spin-parity
• Heavy baryons in the relativized quark model with chromodynamics
• Observation of the B${}_{\mathrm{s}}^0$ $\to$ X(3872)$\varphi$ decay
• Decays of Roper-like singly heavy baryons in a chiral model
• Observation of the ${\Lambda }_{\text{b}}^0$ $\to$ J/$\psi {\Xi }^{-}$K${}^{+}$ decay
• Decay widths and mass spectra of single bottom baryons
• 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
• Spectroscopic properties of $1F$-wave singly bottom baryons
• First exclusive reconstruction of the B${}^{\ast +}$, B${}^{\ast 0}$, and B${}_{\text{s}}^{\ast 0}$ mesons and precise measurement of their masses