JHEP 09 (2016) 136 A measurement of the production cross-section of Z bosons in pp collisions at
$\sqrt{s} = 13$ TeV is presented using dimuon and dielectron final states in
LHCb data. The ...cross-section is measured for leptons with pseudorapidities in
the range $2.0 < \eta < 4.5$, transverse momenta $p_\text{T} > 20$ GeV and
dilepton invariant mass in the range $60<m(\ell\ell)<120$ GeV. The integrated
cross-section from averaging the two final states is
\begin{equation*}\sigma_{\text{Z}}^{\ell\ell} = 194.3 \pm 0.9 \pm 3.3 \pm
7.6\text{ pb,}\end{equation*} where the first uncertainty is statistical, the
second is due to systematic effects, and the third is due to the luminosity
determination. In addition, differential cross-sections are measured as
functions of the Z boson rapidity, transverse momentum and the angular variable
$\phi^*_\eta$.
Physics Letters B 762C (2016) pp. 484-492 Using a data set corresponding to an integrated luminosity of $3 fb^{-1}$,
collected by the LHCb experiment in $pp$ collisions at centre-of-mass energies
of ...7 and 8 TeV, the effective lifetime in the $B^0_s \rightarrow J/\psi \eta$
decay mode, $\tau_{\textrm{eff}}$, is measured to be $\tau_{\textrm{eff}} =
1.479 \pm 0.034~\textrm{(stat)} \pm 0.011 ~\textrm{(syst)}$ ps. Assuming $CP$
conservation, $\tau_{\textrm{eff}}$ corresponds to the lifetime of the light
$B_s^0$ mass eigenstate. This is the first measurement of the effective
lifetime in this decay mode.
Phys. Rev. D 98, 112005 (2018) This paper presents a study of the production of a single $W$ boson in
association with one or more jets in proton-antiproton collisions at
$\sqrt{s}=1.96$ TeV, using ...the entire data set collected in 2001-2011 by the
Collider Detector at Fermilab at the Tevatron, which corresponds to an
integrated luminosity of $9.0$ fb$^{-1}$. The $W$ boson is identified through
its leptonic decays into electron and muon. The production cross sections are
measured for each leptonic decay mode and combined after testing that the ratio
of the $W(\rightarrow \mu\nu)+$jets cross section to the $W(\rightarrow
e\nu)+$jets cross section agrees with the hypothesis of $e$-$\mu$ lepton
universality. The combination of measured cross sections, differential in the
inclusive jet multiplicity ($W+\geqslant N$ jets with $N=1,\,2,\,3, \textrm{or
}4$) and in the transverse energy of the leading jet, are compared with
theoretical predictions.
Phys. Rev. Lett. 117, 061803 (2016) The $CP$ asymmetry in the mixing of $B_s^0$ and $\overline{B}{}_s^0$ mesons
is measured in proton-proton collision data corresponding to an integrated
luminosity ...of 3.0 fb$^{-1}$, recorded by the LHCb experiment at centre-of-mass
energies of 7 and 8 TeV. Semileptonic $B_s^0$ and $\overline{B}{}_s^0$ decays
are studied in the inclusive mode $D_s^{\mp} \mu^{\pm} \nu_{\mu} X$ with the
$D_s^{\mp}$ mesons reconstructed in the $K^+ K^- \pi^{\mp}$ final state.
Correcting the observed charge asymmetry for detection and background effects,
the $CP$ asymmetry is found to be $a_{\text{sl}}^s = (0.39 \pm 0.26 \pm 0.20)
\% $, where the first uncertainty is statistical and the second systematic.
This is the most precise measurement of $a_{\text{sl}}^s$ to date. It is
consistent with the prediction from the Standard Model and will constrain new
models of particle physics.
Clofilium was studied in three experimental models. In non-ischemic and chronically infarcted canine hearts, clofilium (0.5-2 mg/kg) produced a dose-dependent increase in electrical ventricular ...fibrillation threshold (VFT), but prolonged the effective refractory period (ERP) of normal myocardium in only the non-ischemic heart. When chronically infarcted hearts were subjected to programmed electrical stimulation, 1 mg/kg of clofilium inhibited the re-induction of either ventricular tachycardia or ventricular fibrillation in 5 of 6 animals and slowed the rate of the induced tachycardia in the sixth. Clofilium, however, failed to alter ventricular refractory periods of normal myocardium at either twice diastolic threshold current (176 +/- 5 ms control vs. 187 +/- 9 ms post-clofilium, P greater than 0.05) or at 10 mA (134 +/- 6 ms control vs. 137 +/- 13 ms post-clofilium, P greater than 0.05). In addition, chronic administration of clofilium (2 mg/kg, i.v., followed by 1 mg/kg every 12 h) was ineffective in decreasing mortality in a canine model of sudden coronary death. Of 10 saline-treated conscious animals subjected to an electrically-induced intimal lesion of the left circumflex coronary artery in the presence of a previous ischemic insult, all 10 died suddenly of ventricular fibrillation within 173 +/- 45 min after current application. Under similar conditions, 7 clofilium-treated animals died suddenly within 249 +/- 88 min (P greater than 0.05) after current application while 3 animals survived (P greater than 0.10). Clofilium did, however, elevate the effective refractory period in these animals (150 +/- 3 ms saline-treated vs. 195 +/- 7 ms clofilium-treated). It is concluded from our data that there is little relationship between clofilium's electrophysiologic actions in normal myocardium and antiarrhythmic effects. Furthermore, simple prolongation of refractoriness in normal non-ischemic myocardium may be insufficient for the prevention of ventricular fibrillation which develops in response to a transient ischemic event superimposed on a chronically injured myocardium.
Phys. Lett. B762 (2016) 253-262 A time-dependent angular analysis of $B_s^0\to\psi(2S)\phi$ decays is
performed using data recorded by the LHCb experiment. The data set corresponds
to an integrated ...luminosity of 3.0\invfb collected during Run 1 of the LHC. The
CP-violating phase and decay-width difference of the $B_s^0$ system are
measured to be $\phi_s = 0.23^{+0.29}_{-0.28} \pm 0.02$ rad and $\Delta\Gamma_s
= 0.066^{+0.041}_{-0.044} \pm 0.007$ ps$^{-1}$, respectively, where the first
uncertainty is statistical and the second systematic. This is the first time
that $\phi_s$ and $\Delta\Gamma_s$ have been measured in a decay containing the
$\psi(2S)$ resonance.
We report the observation and measurement of the mass of the bottom, strange baryon Xi(b)- through the decay chain Xi(b)- -->J/psiXi-, where J/psi-->mu+mu-, Xi- -->Lambdapi-, and Lambda-->ppi-. A ...signal is observed whose probability of arising from a background fluctuation is 6.6 x 10(-15), or 7.7 Gaussian standard deviations. The Xi(b)- mass is measured to be 5792.9+/-2.5(stat) +/- 1.7(syst) MeV/c2.
Phys. Rev. D 95, 012002 (2017) The first full amplitude analysis of $B^+\to J/\psi \phi K^+$ with
$J/\psi\to\mu^+\mu^-$, $\phi\to K^+K^-$ decays is performed with a data sample
of 3 fb$^{-1}$ of $pp$ ...collision data collected at $\sqrt{s}=7$ and $8$ TeV
with the LHCb detector. The data cannot be described by a model that contains
only excited kaon states decaying into $\phi K^+$, and four $J/\psi\phi$
structures are observed, each with significance over $5$ standard deviations.
The quantum numbers of these structures are determined with significance of at
least $4$ standard deviations. The lightest has mass consistent with, but width
much larger than, previous measurements of the claimed $X(4140)$ state. The
model includes significant contributions from a number of expected kaon
excitations, including the first observation of the $K^{*}(1680)^+\to\phi K^+$
transition.
Phys. Rev. Lett. 118, 022003 (2017) The first full amplitude analysis of $B^+\to J/\psi \phi K^+$ with
$J/\psi\to\mu^+\mu^-$, $\phi\to K^+K^-$ decays is performed with a data sample
of 3 fb$^{-1}$ of ...$pp$ collision data collected at $\sqrt{s}=7$ and $8$ TeV
with the LHCb detector. The data cannot be described by a model that contains
only excited kaon states decaying into $\phi K^+$, and four $J/\psi\phi$
structures are observed, each with significance over $5$ standard deviations.
The quantum numbers of these structures are determined with significance of at
least $4$ standard deviations. The lightest has mass consistent with, but width
much larger than, previous measurements of the claimed $X(4140)$ state.
We present the results of a search for neutral Higgs bosons produced in association with b quarks in pp-->bb(phi)-->bbb final states with 91+/-7 pb(-1) of pp collisions at sqrts = 1.8 TeV recorded by ...the Collider Detector at Fermilab. We find no evidence of such a signal and the data are interpreted in the context of the neutral Higgs sector of the minimal supersymmetric extension of the standard model. With basic parameter choices for the supersymmetric scale and the stop-quark mixing, we derive 95% C.L. lower mass limits for neutral Higgs bosons for tan(beta) values in excess of 35.
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