Neutrino-Induced Coherent π^{+} Production in C, CH, Fe, and Pb at ⟨E_{ν}⟩∼6 GeV

MINERvA has measured the ν_{μ}-induced coherent π^{+} cross section simultaneously in hydrocarbon (CH), graphite (C), iron (Fe), and lead (Pb) targets using neutrinos from 2 to 20 GeV. The measurements exceed the predictions of the Rein-Sehgal and Berger-Sehgal PCAC based models at multi-GeV ν_{μ} energies and at produced π^{+} energies and angles, E_{π}>1  GeV and θ_{π}<10°. Measurements of the cross-section ratios of Fe and Pb relative to CH reveal the effective A scaling to increase from an approximate A^{1/3} scaling at few GeV to an A^{2/3} scaling for E_{ν}>10  GeV.

Simultaneous Measurement of Muon Neutrino ν_{μ} Charged-Current Single π^{+} Production in CH, C, H_{2}O, Fe, and Pb Targets in MINERvA

Neutrino-induced charged-current single π^{+} production in the Δ(1232) resonance region is of considerable interest to accelerator-based neutrino oscillation experiments. In this Letter, high statistic differential cross sections are reported for the semiexclusive reaction ν_{μ}A→μ^{-}π^{+}+ nucleon(s) on scintillator, carbon, water, iron, and lead targets recorded by MINERvA using a wideband ν_{μ} beam with ⟨E_{ν}⟩≈6  GeV. Suppression of the cross section at low Q^{2} and enhancement of low T_{π} are observed in both light and heavy nuclear targets compared with phenomenological models used in current neutrino interaction generators. The cross sections per nucleon for iron and lead compared with CH across the kinematic variables probed are 0.8 and 0.5 respectively, a scaling which is also not predicted by current generators.

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6  ×  6  ×  6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

Odderon Exchange from Elastic Scattering Differences between pp and pp[over ¯] Data at 1.96 TeV and from pp Forward Scattering Measurements

We describe an analysis comparing the pp[over ¯] elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of sqrt[s]=1.96  TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound.

Prospects for beyond the Standard Model physics searches at the Deep Underground Neutrino Experiment: DUNE Collaboration

The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE's sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach.

Publisher's Note: Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer [Phys. Rev. Lett. 116, 071802 (2016)]

This corrects the article DOI: 10.1103/PhysRevLett.116.071802.

Measurement of Final-State Correlations in Neutrino Muon-Proton Mesonless Production on Hydrocarbon at ⟨E_{ν}⟩=3 GeV

Final-state kinematic imbalances are measured in mesonless production of ν_{μ}+A→μ^{-}+p+X in the MINERvA tracker. Initial- and final-state nuclear effects are probed using the direction of the μ^{-}-p transverse momentum imbalance and the initial-state momentum of the struck neutron. Differential cross sections are compared to predictions based on current approaches to medium modeling. These models underpredict the cross section at intermediate intranuclear momentum transfers that generally exceed the Fermi momenta. As neutrino interaction models need to correctly incorporate the effect of the nucleus in order to predict neutrino energy resolution in oscillation experiments, this result points to a region of phase space where additional cross section strength is needed in current models, and demonstrates a new technique that would be suitable for use in fine-grained liquid argon detectors where the effect of the nucleus may be even larger.

Measurement of the Effective Weak Mixing Angle in pp[over ¯]→Z/γ^{*}→ℓ^{+}ℓ^{-} Events

We present a measurement of the effective weak mixing angle parameter sin^{2}θ_{eff}^{ℓ} in pp[over ¯]→Z/γ^{*}→μ^{+}μ^{-} events at a center-of-mass energy of 1.96 TeV, collected by the D0 detector at the Fermilab Tevatron Collider and corresponding to 8.6  fb^{-1} of integrated luminosity. The measured value of sin^{2}θ_{eff}^{ℓ}[μμ]=0.23016±0.00064 is further combined with the result from the D0 measurement in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} events, resulting in sin^{2}θ_{eff}^{ℓ}[comb]=0.23095±0.00040. This combined result is the most precise measurement from a single experiment at a hadron collider and is the most precise determination using the coupling of the Z/γ^{*} to light quarks.

Antineutrino Charged-Current Reactions on Hydrocarbon with Low Momentum Transfer

We report on multinucleon effects in low momentum transfer (<0.8  GeV/c) antineutrino interactions on plastic (CH) scintillator. These data are from the 2010-2011 antineutrino phase of the MINERvA experiment at Fermilab. The hadronic energy spectrum of this inclusive sample is well described when a screening effect at a low energy transfer and a two-nucleon knockout process are added to a relativistic Fermi gas model of quasielastic, Δ resonance, and higher resonance processes. In this analysis, model elements introduced to describe previously published neutrino results have quantitatively similar benefits for this antineutrino sample. We present the results as a double-differential cross section to accelerate the investigation of alternate models for antineutrino scattering off nuclei.

Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of sqrt[s]=1.96  TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is A_{FB}^{tt[over ¯]}=0.128±0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.

Direct Measurement of Nuclear Dependence of Charged Current Quasielasticlike Neutrino Interactions Using MINERvA

Charged-current ν_{μ} interactions on carbon, iron, and lead with a final state hadronic system of one or more protons with zero mesons are used to investigate the influence of the nuclear environment on quasielasticlike interactions. The transferred four-momentum squared to the target nucleus, Q^{2}, is reconstructed based on the kinematics of the leading proton, and differential cross sections versus Q^{2} and the cross-section ratios of iron, lead, and carbon to scintillator are measured for the first time in a single experiment. The measurements show a dependence on the atomic number. While the quasielasticlike scattering on carbon is compatible with predictions, the trends exhibited by scattering on iron and lead favor a prediction with intranuclear rescattering of hadrons accounted for by a conventional particle cascade treatment. These measurements help discriminate between different models of both initial state nucleons and final state interactions used in the neutrino oscillation experiments.

Measurement of Neutral-Current K^{+} Production by Neutrinos using MINERvA

Neutral-current production of K^{+} by atmospheric neutrinos is a background in searches for the proton decay p→K^{+}ν[over ¯]. Reactions such as νp→νK^{+}Λ are indistinguishable from proton decays when the decay products of the Λ are below detection threshold. Events with K^{+} are identified in MINERvA by reconstructing the timing signature of a K^{+} decay at rest. A sample of 201 neutrino-induced neutral-current K^{+} events is used to measure differential cross sections with respect to the K^{+} kinetic energy, and the non-K^{+} hadronic visible energy. An excess of events at low hadronic visible energy is observed relative to the prediction of the neut event generator. Good agreement is observed with the cross section prediction of the genie generator. A search for photons from π^{0} decay, which would veto a neutral-current K^{+} event in a proton decay search, is performed, and a 2σ deficit of detached photons is observed relative to the genie prediction.

Evidence of Coherent K^{+} Meson Production in Neutrino-Nucleus Scattering

Neutrino-induced charged-current coherent kaon production ν_{μ}A→μ^{-}K^{+}A is a rare, inelastic electroweak process that brings a K^{+} on shell and leaves the target nucleus intact in its ground state. This process is significantly lower in rate than the neutrino-induced charged-current coherent pion production because of Cabibbo suppression and a kinematic suppression due to the larger kaon mass. We search for such events in the scintillator tracker of MINERvA by observing the final state K^{+}, μ^{-}, and no other detector activity, and by using the kinematics of the final state particles to reconstruct the small momentum transfer to the nucleus, which is a model-independent characteristic of coherent scattering. We find the first experimental evidence for the process at 3σ significance.

Evidence for a B_{s}^{0}π^{±} State

We report evidence for a narrow structure, X(5568), in the decay sequence X(5568)→B_{s}^{0}π^{±}, B_{s}^{0}→J/ψϕ, J/ψ→μ^{+}μ^{-}, ϕ→K^{+}K^{-}. This is evidence for the first instance of a hadronic state with valence quarks of four different flavors. The mass and natural width of this state are measured to be m=5567.8±2.9(stat)_{-1.9}^{+0.9}(syst)  MeV/c^{2} and Γ=21.9±6.4(stat)_{-2.5}^{+5.0}(syst)  MeV/c^{2}. If the decay is X(5568)→B_{s}^{*}π^{±}→B_{s}^{0}γπ^{±} with an unseen γ, m(X(5568)) will be shifted up by m(B_{s}^{*})-m(B_{s}^{0})∼49  MeV/c^{2}. This measurement is based on 10.4  fb^{-1} of pp[over ¯] collision data at sqrt[s]=1.96  TeV collected by the D0 experiment at the Fermilab Tevatron collider.

Measurement of Electron Neutrino Quasielastic and Quasielasticlike Scattering on Hydrocarbon at ⟨E_{ν}⟩=3.6 GeV

The first direct measurement of electron neutrino quasielastic and quasielasticlike scattering on hydrocarbon in the few-GeV region of incident neutrino energy has been carried out using the MINERvA detector in the NuMI beam at Fermilab. The flux-integrated differential cross sections in the electron production angle, electron energy, and Q^{2} are presented. The ratio of the quasielastic, flux-integrated differential cross section in Q^{2} for ν_{e} with that of similarly selected ν_{μ}-induced events from the same exposure is used to probe assumptions that underpin conventional treatments of charged-current ν_{e} interactions used by long-baseline neutrino oscillation experiments. The data are found to be consistent with lepton universality and are well described by the predictions of the neutrino event generator GENIE.

Evidence for Simultaneous Production of J/ψ and ϒ Mesons

We report evidence for the simultaneous production of J/ψ and ϒ mesons in 8.1  fb^{-1} of data collected at sqrt[s]=1.96  TeV by the D0 experiment at the Fermilab pp[over ¯] Tevatron Collider. Events with these characteristics are expected to be produced predominantly by gluon-gluon interactions. In this analysis, we extract the effective cross section characterizing the initial parton spatial distribution, σ_{eff}=2.2±0.7(stat)±0.9(syst)  mb.

Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer

Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current ν_{μ} interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

Inclusive Production of the X(4140) State in pp[over ¯] Collisions at D0

We present a study of the inclusive production of the X(4140) state with the decay to the J/ψϕ final state in hadronic collisions. Based on 10.4  fb^{-1} of pp[over ¯] collision data collected by the D0 experiment at the Fermilab Tevatron collider, we report the first evidence for the prompt production of an X(4140) state and find the fraction of X(4140) events originating from b hadrons to be f_{b}=0.39±0.07(stat)±0.10(syst). The ratio of the nonprompt X(4140) production rate to the B_{s}^{0} yield in the same channel is R=0.19±0.05(stat)±0.07(syst). The values of the mass M=4152.5±1.7(stat)_{-5.4}^{+6.2}(syst)  MeV and width Γ=16.3±5.6(stat)±11.4(syst)  MeV are consistent with previous measurements.

Search for Violation of CPT and Lorentz Invariance in Bs(0) Meson Oscillations

We present the first search for CPT-violating effects in the mixing of Bs(0) mesons using the full Run II data set with an integrated luminosity of 10.4  fb(-1) of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. We measure the CPT-violating asymmetry in the decay Bs(0)→μ(±)Ds(±) as a function of celestial direction and sidereal phase. We find no evidence for CPT-violating effects and place limits on the direction and magnitude of flavor-dependent CPT- and Lorentz-invariance violating coupling coefficients. We find 95% confidence intervals of Δa⊥<1.2×10(-12)  GeV and (-0.8<ΔaT-0.396ΔaZ<3.9)×10(-13)  GeV.

Tevatron Combination of Single-Top-Quark Cross Sections and Determination of the Magnitude of the Cabibbo-Kobayashi-Maskawa Matrix Element V_{tb}

We present the final combination of CDF and D0 measurements of cross sections for single-top-quark production in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb^{-1} per experiment. The t-channel cross section is measured to be σ_{t}=2.25_{-0.31}^{+0.29} pb. We also present the combinations of the two-dimensional measurements of the s- vs t-channel cross section. In addition, we give the combination of the s+t channel cross section measurement resulting in σ_{s+t}=3.30_{-0.40}^{+0.52} pb, without assuming the standard model value for the ratio σ_{s}/σ_{t}. The resulting value of the magnitude of the top-to-bottom quark coupling is |V_{tb}|=1.02_{-0.05}^{+0.06}, corresponding to |V_{tb}|>0.92 at the 95% C.L.

Measurement of the Effective Weak Mixing Angle in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} Events

We present a measurement of the fundamental parameter of the standard model, the weak mixing angle sin^{2}θ_{eff}^{ℓ} which determines the relative strength of weak and electromagnetic interactions, in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} events at a center of mass energy of 1.96 TeV, using data corresponding to 9.7 fb^{-1} of integrated luminosity collected by the D0 detector at the Fermilab Tevatron. The effective weak mixing angle is extracted from the forward-backward charge asymmetry as a function of the invariant mass around the Z boson pole. The measured value of sin^{2}θ_{eff}^{ℓ}=0.23147±0.00047 is the most precise measurement from light quark interactions to date, with a precision close to the best LEP and SLD results.

Tevatron constraints on models of the Higgs boson with exotic spin and parity using decays to bottom-antibottom quark pairs

Combined constraints from the CDF and D0 Collaborations on models of the Higgs boson with exotic spin J and parity P are presented and compared with results obtained assuming the standard model value JP=0+. Both collaborations analyzed approximately 10  fb(-) of proton-antiproton collisions with a center-of-mass energy of 1.96 TeV collected at the Fermilab Tevatron. Two models predicting exotic Higgs bosons with JP=0- and JP=2+ are tested. The kinematic properties of exotic Higgs boson production in association with a vector boson differ from those predicted for the standard model Higgs boson. Upper limits at the 95% credibility level on the production rates of the exotic Higgs bosons, expressed as fractions of the standard model Higgs boson production rate, are set at 0.36 for both the JP=0- hypothesis and the JP=2+ hypothesis. If the production rate times the branching ratio to a bottom-antibottom pair is the same as that predicted for the standard model Higgs boson, then the exotic bosons are excluded with significances of 5.0 standard deviations and 4.9 standard deviations for the JP=0- and JP=2+ hypotheses, respectively.

Measurement of the B(s)(0) lifetime in the flavor-specific decay channel B(s)(0)→D(s)(-)μ(+)νX

We present an updated measurement of the B(s)(0) lifetime using the semileptonic decays B(s)(0)→D(s)(-)μ(+)νX, with D(s)(-)→ϕπ(-) and ϕ→K(+)K(-) (and the charge conjugate process). This measurement uses the full Tevatron Run II sample of proton-antiproton collisions at √[s]=1.96  TeV, comprising an integrated luminosity of 10.4  fb(-1). We find a flavor-specific lifetime τ(fs)(B(s)(0))=1.479±0.010(stat)±0.021(syst)  ps. This technique is also used to determine the B(0) lifetime using the analogous B(0)→D(-)μ(+)νX decay with D(-)→ϕπ(-) and ϕ→K(+)K(-), yielding τ(B(0))=1.534±0.019(stat)±0.021(syst)  ps. Both measurements are consistent with the current world averages, and the B(s)(0) lifetime measurement is one of the most precise to date. Taking advantage of the cancellation of systematic uncertainties, we determine the lifetime ratio τ(fs)(B(s)(0))/τ(B(0))=0.964±0.013(stat)±0.007(syst).

Measurement of the forward-backward asymmetry in the production of B(±) mesons in pp̄ collisions at √s=1.96 TeV

We present a measurement of the forward-backward asymmetry in the production of B(±) mesons, A(FB)(B(±)), using B(±)→J/ψK(±) decays in 10.4  fb(-1) of pp̄ collisions at sqrt[s]=1.96  TeV collected by the D0 experiment during Run II of the Tevatron collider. A nonzero asymmetry would indicate a preference for a particular flavor, i.e., b quark or ̄b antiquark, to be produced in the direction of the proton beam. We extract A(FB)(B(±)) from a maximum likelihood fit to the difference between the numbers of forward- and backward-produced B(±) mesons. We measure an asymmetry consistent with zero: A(FB)(B(±))=[-0.24±0.41  (stat)±0.19  (syst)]%.

Constraints on models for the Higgs boson with exotic spin and parity in VH → Vbb final states

We present constraints on models containing non-standard-model values for the spin J and parity P of the Higgs boson H in up to 9.7 fb(-1) of pp collisions at sqrt[s] = 1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. These are the first studies of Higgs boson J(P) with fermions in the final state. In the ZH → ℓℓbb, WH → ℓνbb, and ZH → ννbb final states, we compare the standard model (SM) Higgs boson prediction, J(P) = 0(+), with two alternative hypotheses, J(P) = 0(-) and J(P) = 2(+). We use a likelihood ratio to quantify the degree to which our data are incompatible with non-SM J(P) predictions for a range of possible production rates. Assuming that the production rate in the signal models considered is equal to the SM prediction, we reject the J(P) = 0(-) and J(P) = 2(+) hypotheses at the 97.6% CL and at the 99.0% CL, respectively. The expected exclusion sensitivity for a J(P) = 0(-) (J(P) = 2(+)) state is at the 99.86% (99.94%) CL. Under the hypothesis that our data are the result of a combination of the SM-like Higgs boson and either a J(P) = 0(-) or a J(P) = 2(+) signal, we exclude a J(P) = 0(-) fraction above 0.80 and a J(P) = 2(+) fraction above 0.67 at the 95% CL. The expected exclusion covers J(P) = 0(-) (J(P) = 2(+)) fractions above 0.54 (0.47).

Precision measurement of the top quark mass in lepton + jets final States

We measure the mass of the top quark in lepton+jets final states using the full sample of pp collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at sqrt[s] = 1.96 TeV, corresponding to 9.7 fb(-1) of integrated luminosity. We use a matrix element technique that calculates the probabilities for each event to result from tt production or background. The overall jet energy scale is constrained in situ by the mass of the W boson. We measure m(t) = 174.98 ± 0.76 GeV. This constitutes the most precise single measurement of the top-quark mass.

Observation of s-channel production of single top quarks at the Tevatron

We report the first observation of single-top-quark production in the s channel through the combination of the CDF and D0 measurements of the cross section in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb(-1) per experiment. The measured cross section is σ(s) = 1.29(-0.24)(+0.26) pb. The probability of observing a statistical fluctuation of the background to a cross section of the observed size or larger is 1.8 × 10(-10), corresponding to a significance of 6.3 standard deviations for the presence of an s-channel contribution to the production of single-top quarks.

Measurement of the W boson production charge asymmetry in pp̄→W+X→eν+X events at √s=1.96 TeV

We present a measurement of the W boson production charge asymmetry in pp̄→W+X→eν+X events at a center of mass energy of 1.96 TeV, using 9.7  fb-1 of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider. The neutrino longitudinal momentum is determined by using a neutrino weighting method, and the asymmetry is measured as a function of the W boson rapidity. The measurement extends over wider electron pseudorapidity region than previous results and is the most precise to date, allowing for precise determination of proton parton distribution functions in global fits.

Measurement of the direct CP-violating charge asymmetry in Ds ± → ϕ π ± decays

We present a measurement of the direct CP-violating charge asymmetry in Ds+ → ϕ π(±) decays where the ϕ meson decays to K(+)K(-), using the full Run II data set with an integrated luminosity of 10.4  fb-1 of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. The normalized difference A(CP) in the yield of D(s)(+) and D(s)(-) mesons in these decays is measured by fitting the difference between their reconstructed invariant mass distributions. This results in an asymmetry of A(CP) = [-0.38 ± 0.27]%, which is the most precise measurement of this quantity to date. The result is consistent with the standard model prediction of zero CP asymmetry in this decay.

Measurement of associated production of z bosons with charm quark jets in pp collisions at √s=1.96 TeV

We present the first measurements of the ratios of cross sections σ(pp → Z+c jet)/σ(pp → Z+jet) and σ(pp → Z+c jet)/σ(pp → Z+b jet) for the associated production of a Z boson with at least one charm or bottom quark jet. Jets have transverse momentum ​pT(jet)​>20  GeV and pseudorapidity |​η(jet)​|<2.5. These cross section ratios are measured differentially as a function of jet and Z boson transverse momenta, based on 9.7  fb(-1) of pp collisions collected with the D0 detector at the Fermilab Tevatron Collider at √s=1.96  TeV. The measurements show significant deviations from perturbative QCD calculations and predictions from various event generators.

Measurement of direct CP violation parameters in B± → J/ψK± and B± → J/ψπ± decays with 10.4 fb-1 of Tevatron data

We present a measurement of the direct CP-violating charge asymmetry in B(±) mesons decaying to J/ψK(±) and J/ψπ(±) where J/ψ decays to μ(+) μ(-), using the full run II data set of 10.4 fb(-1) of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. A difference in the yield of B(-) and B(+) mesons in these decays is found by fitting to the difference between their reconstructed invariant mass distributions resulting in asymmetries of A(J/ψK) = [0.59 ± 0.37]%, which is the most precise measurement to date, and A(J/ψπ) = [-4.2 ± 4.5]%. Both measurements are consistent with standard model predictions.

Measurement of the semileptonic charge asymmetry using B(s)(0) → D(s)μX decays

We present a measurement of the time-integrated flavor-specific semileptonic charge asymmetry in the decays of B(s)(0) mesons that have undergone flavor mixing, a(sl)(s), using B(s)(0)(B(s)(0)) → D(s)(-/+) μ(±) X decays, with D(s)(-/+) → [symbol: see text]π(-/+) and [symbol: see text]→ K(+) K(-), using 10.4 fb(-1) of proton-antiproton collisions collected by the D0 detector during Run II at the Fermilab Tevatron Collider. A fit to the difference between the time-integrated D(s)(-) and D(s)(+) mass distributions of the B(s)(0) and B(s)(0) candidates yields the flavor-specific asymmetry a(sl)(s) = [-1.12 ± 0.74(stat) ± 0.17(syst)]%, which is the most precise measurement and in agreement with the standard model prediction.