An Experimental Education Project for Consultations of Older Adults during the Pandemic and Healthcare Lockdown

Objective: To develop a mentor-supervised, interprofessional, geriatric telemedicine experiential education project in response to the COVID-19 pandemic. Method: Medical and pharmacy students collaborated via remote consultations to address the coexistence of multimorbidity and polypharmacy in geriatric patients. In-depth interviews of students and patients as well as Likert scale-based telephonic survey were performed for a comprehensive evaluation of the project’s significance. Results: To date, 49 consultations have been conducted. Remote consultations performed by medical and pharmacy students working collaboratively were beneficial for both students, participants. Conclusions and Practice Implications: This experimental education project provided students with authentic challenges while simultaneously delivering care to the older adults who are susceptible to disruption of care associated with the pandemic. Further development and expanded implementation of such approaches may be a post-pandemic practice to provide more accessible care for senior patients while incorporating interprofessional education

Search for long-lived particles decaying to e±μ∓νe^\pm \mu^\mp \nu

International audienceLong-lived particles decaying to ${e ^\pm } {\mu ^\mp } {\nu }$, with masses between 7 and $50 \,\text {GeV/}c^2$ and lifetimes between 2 and $50 \,\text {ps}$, are searched for by looking at displaced vertices containing electrons and muons of opposite charges. The search is performed using $5.4 \,\text {fb} ^{-1}$ of $p p$ collisions collected with the LHCb detector at a centre-of-mass energy of $\sqrt{s} = 13 \,\text {TeV}$. Three mechanisms of production of long-lived particles are considered: the direct pair production from quark interactions, the pair production from the decay of a Standard-Model-like Higgs boson with a mass of $125 \,\text {GeV/}c^2$, and the charged current production from an on-shell $W$ boson with an additional lepton. No evidence of these long-lived states is obtained and upper limits on the production cross-section times branching fraction are set on the different production modes

Observation of Multiplicity Dependent Prompt χc1(3872)\chi_{c1}(3872) and ψ(2S)\psi(2S) Production in pppp Collisions

The production of $χ_{c1}$(3872) and $ψ$(2S) hadrons is studied as a function of charged particle multiplicity in pp collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 2 fb-1. For both states, the fraction that is produced promptly at the collision vertex is found to decrease as charged particle multiplicity increases. The ratio of $χ_{c1}$(3872) to $ψ$(2S) cross sections for promptly produced particles is also found to decrease with multiplicity, while no significant dependence on multiplicity is observed for the equivalent ratio of particles produced away from the collision vertex in b-hadron decays. This behavior is consistent with a calculation that models the $χ_{c1}$(3872) structure as a compact tetraquark. Comparisons with model calculations and implications for the binding energy of the $χ_{c1}$(3872) state are discussed

First observation of the decay Λb0→ηc(1S)pK−\Lambda_b^0 \to \eta_c(1S) p K^-

International audienceThe decay Λb0→ηc(1S)pK- is observed for the first time using a data sample of proton-proton collisions, corresponding to an integrated luminosity of 5.5  fb-1, collected with the LHCb experiment at a center-of-mass energy of 13 TeV. The branching fraction of the decay is measured, using the Λb0→J/ψpK- decay as a normalization mode, to be B(Λb0→ηc(1S)pK-)=(1.06±0.16±0.06-0.19+0.22)×10-4, where the quoted uncertainties are statistical, systematic and due to external inputs, respectively. A study of the ηc(1S)p mass spectrum is performed to search for the Pc(4312)+ pentaquark state. No evidence is observed and an upper limit of B(Λb0→Pc(4312)+K-)×B(Pc(4312)+→ηc(1S)p)B(Λb0→ηc(1S)pK-)<0.24 is obtained at the 95% confidence level

Measurement of χc1_{c1}(3872) production in proton-proton collisions at s \sqrt{s} = 8 and 13 TeV

International audienceThe production cross-section of the χ$_{c1}$(3872) state relative to the ψ(2S) meson is measured using proton-proton collision data collected with the LHCb experiment at centre-of-mass energies of $\sqrt{s}$ = 8 and 13 TeV, corresponding to integrated luminosities of 2.0 and 5.4 fb$^{−1}$, respectively. The two mesons are reconstructed in the J/ψπ$^{+}$π$^{−}$ final state. The ratios of the prompt and nonprompt χ$_{c1}$(3872) to ψ(2S) production cross-sections are measured as a function of transverse momentum, p$_{T}$, and rapidity, y, of the χ$_{c1}$(3872) and ψ(2S) states, in the kinematic range 4 < p$_{T}$< 20 GeV/c and 2.0 < y < 4.5. The prompt ratio is found to increase with p$_{T}$, independently of y. For the prompt component, the double ratio of the χ$_{c1}$(3872) and ψ(2S) production cross-sections between 13 and 8 TeV is observed to be consistent with unity, independent of p$_{T}$ and centre-of-mass energy.[graphic not available: see fulltext

Measurement of CP Violation in the Decay B+→K+π0B^{+} \rightarrow K^{+} \pi^{0}

International audienceA measurement of CP violation in the decay B+→K+π0 is reported using data corresponding to an integrated luminosity of 5.4  fb-1 collected with the LHCb experiment at a center-of-mass energy of s=13  TeV. The CP asymmetry is measured to be 0.025±0.015±0.006±0.003, where the uncertainties are statistical, systematic, and due to an external input. This is the most precise measurement of this quantity. It confirms and significantly enhances the observed anomalous difference between the direct CP asymmetries of the B+→K+π- and B+→K+π0 decays, known as the Kπ puzzle

Precision measurement of forward ZZ boson production in proton-proton collisions at s=13\sqrt{s} = 13 TeV

A precision measurement of the $Z$ boson production cross-section at $\sqrt{s} = 13$ TeV in the forward region is presented, using $pp$ collision data collected by the LHCb detector, corresponding to an integrated luminosity of 5.1 fb$^{-1}$. The production cross-section is measured using $Z\rightarrow\mu^+\mu^-$ events within the fiducial region defined as pseudorapidity $2.020$ GeV/$c$ for both muons and dimuon invariant mass $60<M_{\mu\mu}<120$ GeV/$c^2$. The integrated cross-section is determined to be \begin{equation*} \sigma(Z\rightarrow\mu^+\mu^-) = 195.3 \pm 0.2 \pm 1.5 \pm 3.9~pb, \end{equation*} where the first uncertainty is statistical, the second is systematic, and the third is due to the luminosity determination. The measured results are in agreement with theoretical predictions, including a prediction at next-to-next-to-leading order in perturbative quantum chromodynamics and a prediction with resummation

Analysis of Neutral B-Meson Decays into Two Muons

International audienceBranching fraction and effective lifetime measurements of the rare decay Bs0→μ+μ- and searches for the decays B0→μ+μ- and Bs0→μ+μ-γ are reported using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a luminosity of 9  fb-1. The branching fraction B(Bs0→μ+μ-)=(3.09-0.43-0.11+0.46+0.15)×10-9 and the effective lifetime τ(Bs0→μ+μ-)=2.07±0.29±0.03  ps are measured, where the first uncertainty is statistical and the second systematic. No significant signal for B0→μ+μ- and Bs0→μ+μ-γ decays is found and upper limits B(B0→μ+μ-)&lt;2.6×10-10 and B(Bs0→μ+μ-γ)&lt;2.0×10-9 at the 95% C.L. are determined, where the latter is limited to the range mμμ&gt;4.9  GeV/c2. The results are in agreement with the standard model expectations

Observation of the Mass Difference Between Neutral Charm-Meson Eigenstates

International audienceA measurement of mixing and CP violation in neutral charm mesons is performed using data reconstructed in proton-proton collisions collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4  fb-1. A total of 30.6 million D0→KS0π+π- decays are analyzed using a method optimized for the measurement of the mass difference between neutral charm-meson eigenstates. Allowing for CP violation in mixing and in the interference between mixing and decay, the mass and decay-width differences are measured to be xCP=[3.97±0.46(stat)±0.29(syst)]×10-3 and yCP=[4.59±1.20(stat)±0.85(syst)]×10-3, respectively. The CP-violating parameters are measured as Δx=[-0.27±0.18(stat)±0.01(syst)]×10-3 and Δy=[0.20±0.36(stat)±0.13(syst)]×10-3. This is the first observation of a nonzero mass difference in the D0 meson system, with a significance exceeding seven standard deviations. The data are consistent with CP symmetry and improve existing constraints on the associated parameters

Angular analysis of B0→D∗−Ds∗+ {B}^0\to {D}^{\ast -}{D}_s^{\ast +} with Ds∗+→Ds+γ {D}_s^{\ast +}\to {D}_s^{+}\gamma decays

International audienceThe first full angular analysis of the ${B}^0\to {D}^{\ast -}{D}_s^{\ast +}$ decay is performed using 6 fb$^{−1}$ of pp collision data collected with the LHCb experiment at a centre-of-mass energy of 13 TeV. The ${D}_s^{\ast +}\to {D}_s^{+}\gamma$ and D$^{*−}$ → ${\overline{D}}^0{\pi}^{-}$ vector meson decays are used with the subsequent ${D}_s^{+}$ → K$^{+}$K$^{−}$π$^{+}$ and ${\overline{D}}^0$ → K$^{+}$π$^{−}$ decays. All helicity amplitudes and phases are measured, and the longitudinal polarisation fraction is determined to be f$_{L}$ = 0.578 ± 0.010 ± 0.011 with world-best precision, where the first uncertainty is statistical and the second is systematic. The pattern of helicity amplitude magnitudes is found to align with expectations from quark-helicity conservation in B decays. The ratio of branching fractions [ℬ(${B}^0\to {D}^{\ast -}{D}_s^{\ast +}$) × ℬ(${D}_s^{\ast +}\to {D}_s^{+}\gamma$)]/ℬ(B$^{0}$ → D$^{*−} {D}_s^{+}$) is measured to be 2.045 ± 0.022 ± 0.071 with world-best precision. In addition, the first observation of the Cabibbo-suppressed B$_{s}$ → D$^{*−} {D}_s^{+}$ decay is made with a significance of seven standard deviations. The branching fraction ratio ℬ(B$_{s}$ → D$^{*−} {D}_s^{+}$)/ℬ(B$^{0}$ → D$^{*−} {D}_s^{+}$) is measured to be 0.049 ± 0.006 ± 0.003 ± 0.002, where the third uncertainty is due to limited knowledge of the ratio of fragmentation fractions.[graphic not available: see fulltext