Relative rates for deep inelastic neutrino and antineutrino scattering without a finalstate muon have been measured. For neutrinos the result is Rν=σ(νμ+nucleon→νμ+hadrons)σ(νμ+nucleon→μ−+hadrons)=0.11±0.05. The corresponding ratio for antineutrinos is Rν¯=0.32±0.09.
No description provided.
We report here additional positive results of a search for muonless neutrino- and anti-neutrino-induced events using an enriched antineutrino beam and a muon identifier of relatively high geometric detection efficiency. The ratio of muonless to muon event rates is observed to be R=0.20±0.05. We observe no background derived from ordinary neutrino or antineutrino interactions that is capable of explaining the muonless signal.
No description provided.
Results are presented of a wire-spark-chamber spectrometer measurement of the differential cross section for π−p elastic scattering at 14.15 GeV/c. The region covered in the square of the four-momentum transfer, t, is 0.01<−t<0.78 (GeV/c)2. The cross section is found to obey very nearly a simple exponential t dependence with no evidence of structure. A fit to the data of the form dσdt∝exp(bt+ct2) on the range 0.05<−t<0.78 (GeV/c)2 (i.e., above the region affected by Coulomb scattering) yields b=8.26±0.10 (GeV/c)2 and c=1.01±0.17 (GeV/c)−4. Considering the results of previous measurements, b≃11 (GeV/c)−2 for −t<0.05 (GeV/c)2, a deviation from the simple exponential near −t≃0.05 (GeV/c)2 is indicated.
No description provided.
In this letter, measurements of the shared momentum fraction ($z_{\rm{g}}$) and the groomed jet radius ($R_{\rm{g}}$), as defined in the SoftDrop algorihm, are reported in \pp collisions at $\sqrt{s} = 200$ GeV collected by the STAR experiment. These substructure observables are differentially measured for jets of varying resolution parameters from $R = 0.2 - 0.6$ in the transverse momentum range $15 < p_{\rm{T, jet}} < 60$ GeV$/c$. These studies show that, in the $p_{\rm{T, jet}}$ range accessible at $\sqrt{s} = 200$ GeV and with increasing jet resolution parameter and jet transverse momentum, the $z_{\rm{g}}$ distribution asymptotically converges to the DGLAP splitting kernel for a quark radiating a gluon. The groomed jet radius measurements reflect a momentum-dependent narrowing of the jet structure for jets of a given resolution parameter, i.e., the larger the $p_{\rm{T, jet}}$, the narrower the first splitting. For the first time, these fully corrected measurements are compared to Monte Carlo generators with leading order QCD matrix elements and leading log in the parton shower, and to state-of-the-art theoretical calculations at next-to-leading-log accuracy. We observe that PYTHIA 6 with parameters tuned to reproduce RHIC measurements is able to quantitatively describe data, whereas PYTHIA 8 and HERWIG 7, tuned to reproduce LHC data, are unable to provide a simultaneous description of both $z_{\rm{g}}$ and $R_{\rm{g}}$, resulting in opportunities for fine parameter tuning of these models for \pp collisions at RHIC energies. We also find that the theoretical calculations without non-perturbative corrections are able to qualitatively describe the trend in data for jets of large resolution parameters at high $p_{\rm{T, jet}}$, but fail at small jet resolution parameters and low jet transverse momenta.
The data points and the error bars represent the mean $p_{\rm{T, jet}}^{\rm{det}}$ and the width (RMS) for a given $p_{\rm{T, jet}}^{\rm{part}}$ selection $R = 0.4$.
The data points and the error bars represent the mean $p_{\rm{T, jet}}^{\rm{det}}$ and the width (RMS) for a given $p_{\rm{T, jet}}^{\rm{part}}$ selection $R = 0.2$.
The data points and the error bars represent the mean $p_{\rm{T, jet}}^{\rm{det}}$ and the width (RMS) for a given $p_{\rm{T, jet}}^{\rm{part}}$ selection $R = 0.6$.
A full set of optimized observables is measured in an angular analysis of the decay B$^0$$\to$ K$^*$(892)$^0\mu^+\mu^-$ using a sample of proton-proton collisions at $\sqrt{s}$ = 13 TeV, collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 140 fb$^{-1}$. The analysis is performed in six bins of the squared invariant mass of the dimuon system, $q^2$, over the range 1.1 $\lt$$q^2$$\lt$ 16 GeV$^2$. The results are among the most precise experimental measurements of the angular observables for this decay and are compared to a variety of predictions based on the standard model. Some of these predictions exhibit tension with the measurements.
Results for the $F_\mathrm{L}$ angular observable. The first uncertainties are statistical and the second systematic.
Results for the $P_1$ angular observable. The first uncertainties are statistical and the second systematic.
Results for the $P_2$ angular observable. The first uncertainties are statistical and the second systematic.
Energy correlators that describe energy-weighted distances between two or three particles in a jet are measured using an event sample of $\sqrt{s}$ = 13 TeV proton-proton collisions collected by the CMS experiment and corresponding to an integrated luminosity of 36.3 fb$^{-1}$. The measured distributions are consistent with the trends in the simulation that reveal two key features of the strong interaction: confinement and asymptotic freedom. By comparing the ratio of the measured three- and two-particle energy correlator distributions with theoretical calculations that resum collinear emissions at approximate next-to-next-to-leading logarithmic accuracy matched to a next-to-leading order calculation, the strong coupling is determined at the Z boson mass: $\alpha_\mathrm{S}(m_\mathrm{Z})$ = 0.1229 $^{+0.0040}_{-0.0050}$, the most precise $\alpha_\mathrm{S}(m_\mathrm{Z})$ value obtained using jet substructure observables.
Unfolded E2C distributions in data compared to MC predictions.
Unfolded E2C distributions in data compared to MC predictions.
Unfolded E2C distributions in data compared to MC predictions.
Results are presented from a search for CP violation in top quark pair production, using proton-proton collisions at a center-of-mass energy of 13 TeV. The data used for this analysis consist of final states with two charged leptons collected by the CMS experiment, and correspond to an integrated luminosity of 35.9 fb$^{-1}$. The search uses two observables, $\mathcal{O}_1$ and $\mathcal{O}_3$, which are Lorentz scalars. The observable $\mathcal{O}_1$ is constructed from the four-momenta of the charged leptons and the reconstructed top quarks, while $\mathcal{O}_3$ consists of the four-momenta of the charged leptons and the b quarks originating from the top quarks. Asymmetries in these observables are sensitive to CP violation, and their measurement is used to determine the chromoelectric dipole moment of the top quark. The results are consistent with the expectation from the standard model.
Measured asymmetries of O_1 and O_3 with statistical uncertainties
The measured asymmetries of O_1 and O_3, and dimensionless CEDM \ImdtG, extracted using the asymmetries in O_1 and O_3, with their uncertainties.
Results for the covariance matrix where the parameters a and b are taken from a linear fit (equation 11) to the different CP-violating samples (CEMD).
A measurement of jet substructure observables is presented using \ttbar events in the lepton+jets channel from proton-proton collisions at $\sqrt{s}=$ 13 TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Multiple jet substructure observables are measured for jets identified as bottom, light-quark, and gluon jets, as well as for inclusive jets (no flavor information). The results are unfolded to the particle level and compared to next-to-leading-order predictions from POWHEG interfaced with the parton shower generators PYTHIA 8 and HERWIG 7, as well as from SHERPA 2 and DIRE2. A value of the strong coupling at the Z boson mass, $\alpha_S(m_\mathrm{Z}) = $ 0.115$^{+0.015}_{-0.013}$, is extracted from the substructure data at leading-order plus leading-log accuracy.
Distribution of $\lambda_{0}^{0}$ (N) reconstructed from charged particles with pt > 1 GeV, unfolded to the particle level.
Distribution of $\lambda_{0}^{2}$ ($p_{T}^{d,*})$ reconstructed from charged particles with pt > 1 GeV, unfolded to the particle level.
Distribution of $\lambda_{0.5}^{1}$ (LHA) reconstructed from charged particles with pt > 1 GeV, unfolded to the particle level.
The measurements of the inclusive and differential fiducial cross sections of the Higgs boson decaying to a pair of photons are presented. The analysis is performed using proton-proton collisions data recorded with the CMS detector at the LHC at a centre-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 137 fb$^{-1}$. The inclusive fiducial cross section is measured to be $\sigma_\mathrm{fid}$ = 73.4 $_{-5.3}^{+5.4}$ (stat) ${}_{-2.2}^{+2.4}$ (syst) fb, in agreement with the standard model expectation of 75.4 $\pm$ 4.1 fb. The measurements are also performed in fiducial regions targeting different production modes and as function of several observables describing the diphoton system, the number of additional jets present in the event, and other kinematic observables. Two double differential measurements are performed. No significant deviations from the standard model expectations are observed.
Differential fiducial higgs to diphoton cross section with respect to $p_{\mathrm{T}}^{\gamma\gamma}$. The last bin in the differential observable extends to infinity and the measured fiducial cross section in this bin is devided by the given bin width
Differential fiducial higgs to diphoton cross section with respect to $p_{\mathrm{T}}^{\gamma\gamma}$. The last bin in the differential observable extends to infinity and the measured fiducial cross section in this bin is devided by the given bin width
Correlation between the measured fiducial cross sections in the different bins of $p_{\mathrm{T}}^{\gamma\gamma}$
Measurements of the top quark polarization and top quark pair ($\mathrm{t\bar{t}}$) spin correlations are presented using events containing two oppositely charged leptons (e$^+$e$^-$, e$^\pm\mu^\mp$, or $\mu^+\mu^-$) produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb$^{-1}$. A set of parton-level normalized differential cross sections, sensitive to each of the independent coefficients of the spin-dependent parts of the $\mathrm{t\bar{t}}$ production density matrix, is measured for the first time at 13 TeV. The measured distributions and extracted coefficients are compared with standard model predictions from simulations at next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD), and from NLO QCD calculations including electroweak corrections. All measurements are found to be consistent with the expectations of the standard model. The normalized differential cross sections are used in fits to constrain the anomalous chromomagnetic and chromoelectric dipole moments of the top quark to $-$0.24 $
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