19 research outputs found

    An embedding technique to determine ττ backgrounds in proton-proton collision data

    Get PDF
    An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

    Performance of missing transverse momentum reconstruction in proton-proton collisions at root s=13 TeV using the CMS detector

    Get PDF
    The performance of missing transverse momentum ((p) over right arrow (miss)(T)) reconstruction algorithms for the CMS experiment is presented, using proton-proton collisions at a center-of-mass energy of 13 TeV, collected at the CERN LHC in 2016. The data sample corresponds to an integrated luminosity of 35.9 fb(-1). The results include measurements of the scale and resolution of (p) over right arrow (miss)(T), and detailed studies of events identified with anomalous (p) over right arrow (miss)(T). The performance is presented of a (p) over right arrow (miss)(T) reconstruction algorithm that mitigates the effects of multiple proton-proton interactions, using the "pileup per particle identification" method. The performance is shown of an algorithm used to estimate the compatibility of the reconstructed (p) over right arrow (miss)(T) with the hypothesis that it originates from resolution effects.Peer reviewe

    Delineation of Drainage Network and Estimation of Total Discharge using Digital Elevation Model (DEM)

    No full text
    The rapid urbanization and the population growth, have increased the demands of fresh water to manage various tasks from domestic to industrial scales. Various man driven sectors such as agriculture, industry and water filtration plants, require fresh water to cater the need of increasing population. Therefore, the management of available fresh water reservoirs is of great importance to save water for a sustainable future “save water save life”. Digital elevation model (DEM) is efficient to extract the drainage network, basin boundaries and to evaluate the volume of fresh water available in study site. We used Arc hydro tools in Arc GIS interface for extraction of drainage network in the study site. Flow direction and accumulation were computed according to Z-value of individual pixel available in the raster grid. A total 127 streams were extracted against 127 catchments. We observed that the catchments bearing steep slopes were incised in comparison to gentle slopes which were mostly eroded. We evaluated the total discharge in cusec using Q=CIA, where the coefficient ‘C’ of rainfall was substituted as 0.76 for each catchment having rocky soil type. The total discharge was estimated as 10871 cusec. GIS tools proved efficient to map watershed in the study site. Full Tex

    Search for supersymmetry in final states with photons and missing transverse momentum in proton-proton collisions at 13 TeV

    No full text
    Results are reported for a search for supersymmetry in final states with photons and missing transverse momentum in proton-proton collisions at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb1^{-1} collected at a center-of-mass energy of 13 TeV using the CMS detector. The results are interpreted in the context of models of gauge-mediated supersymmetry breaking. Production cross section limits are set on gluino and squark pair production in this framework. Gluino masses below 1.86 TeV and squark masses below 1.59 TeV are excluded at 95% confidence level

    An embedding technique to determine ττ\tau\tau backgrounds in proton-proton collision data

    No full text
    An embedding technique is presented to estimate standard model ττ\tau\tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed μμ\mu\mu events and replaced with simulated tau leptons with the same kinematic properties. In this way a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at s=\sqrt{s}= 13 TeV corresponding to an integrated luminosity of 41.5 fb1^{-1}

    Constraints on anomalous HVV couplings from the production of Higgs bosons decaying to τ\tau lepton pairs

    Get PDF
    A study is presented of anomalous HVV interactions of the Higgs boson, including its CP properties. The study uses Higgs boson candidates produced mainly in vector boson fusion and gluon fusion that subsequently decay to a pair of τ\tau leptons. The data were recorded by the CMS experiment at the LHC in 2016 at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 35.9 fb1^{-1}. A matrix element technique is employed for the analysis of anomalous interactions. The results are combined with those from the H4\mathrm{H}\to 4\ell decay channel presented earlier, yielding the most stringent constraints on anomalous Higgs boson couplings to electroweak vector bosons expressed as effective cross-section fractions and phases: the CP-violating parameter fa3cos(ϕa3)=(0.00±0.27)×103f_{a3}\cos(\phi_{a3})=(0.00 \pm 0.27 )\times10^{-3} and the CP-conserving parameters fa2cos(ϕa2)=(0.080.21+1.04)×103f_{a2}\cos(\phi_{a2})=(0.08^{+1.04}_{-0.21})\times10^{-3}, fΛ1cos(ϕΛ1)=(0.000.09+0.53)×103f_{\Lambda1}\cos(\phi_{\Lambda1})=(0.00^{+0.53}_{-0.09})\times10^{-3}, and fΛ1Zγcos(ϕΛ1Zγ)=(0.01.3+1.1)×103f_{\Lambda1}^{\mathrm{Z}\gamma}\cos(\phi_{\Lambda1}^{\mathrm{Z}\gamma})=(0.0^{+1.1}_{-1.3})\times10^{-3}. The current data set does not allow for precise constraints on CP properties in the gluon fusion process. The results are consistent with standard model expectations.A study is presented of anomalous HVV interactions of the Higgs boson, including its CP properties. The study uses Higgs boson candidates produced mainly in vector boson fusion and gluon fusion that subsequently decay to a pair of τ leptons. The data were recorded by the CMS experiment at the LHC in 2016 at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 35.9  fb-1. A matrix element technique is employed for the analysis of anomalous interactions. The results are combined with those from the H→4ℓ decay channel presented earlier, yielding the most stringent constraints on anomalous Higgs boson couplings to electroweak vector bosons expressed as effective cross section fractions and phases: the CP-violating parameter fa3cos(ϕa3)=(0.00±0.27)×10-3 and the CP-conserving parameters fa2cos(ϕa2)=(0.08-0.21+1.04)×10-3, fΛ1cos(ϕΛ1)=(0.00-0.09+0.53)×10-3, and fΛ1Zγcos(ϕΛ1Zγ)=(0.0-1.3+1.1)×10-3. The current dataset does not allow for precise constraints on CP properties in the gluon fusion process. The results are consistent with standard model expectations.A study is presented of anomalous HVV interactions of the Higgs boson, including its CPCP properties. The study uses Higgs boson candidates produced mainly in vector boson fusion and gluon fusion that subsequently decay to a pair of τ\tau leptons. The data were recorded by the CMS experiment at the LHC in 2016 at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 35.9 fb1^{-1}. A matrix element technique is employed for the analysis of anomalous interactions. The results are combined with those from the H 4\to 4\ell decay channel presented earlier, yielding the most stringent constraints on anomalous Higgs boson couplings to electroweak vector bosons expressed as effective cross section fractions and phases: the CPCP-violating parameter fa3cos(ϕa3)f_{a3}\cos(\phi_{a3}) == (0.00±0.27)×103(0.00 \pm 0.27) \times 10^{-3} and the CPCP-conserving parameters fa2cos(ϕa2)f_{a2}\cos(\phi_{a2}) == (0.080.21+1.04)×103(0.08 ^{+1.04}_{-0.21}) \times 10^{-3}, fΛ1cos(ϕΛ1)f_{\Lambda1}\cos(\phi_{\Lambda1}) == (0.000.09+0.53)×103(0.00 ^{+0.53}_{-0.09}) \times 10^{-3}, and fΛ1Zγcos(ϕΛ1Zγ)f_{\Lambda1}^{\mathrm{Z}\gamma}\cos(\phi_{\Lambda1}^{\mathrm{Z}\gamma}) == (0.01.3+1.1)×103(0.0 ^{+1.1}_{-1.3}) \times 10^{-3}. The current dataset does not allow for precise constraints on CPCP properties in the gluon fusion process. The results are consistent with standard model expectations

    Measurement of electroweak production of a W boson in association with two jets in proton-proton collisions at s=\sqrt{s}= 13 TeV

    No full text
    A measurement is presented of electroweak (EW) production of a W boson in association with two jets in proton-proton collisions at s=\sqrt{s}= 13 TeV. The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9 fb1^{-1}. The measurement is performed for the ν\ell\nujj final state (with ν\ell\nu indicating a lepton-neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass mjj>m_\mathrm{jj} > 120 GeV and transverse momenta pTj>p_\mathrm{T j} > 25 GeV. The cross section of the process is measured in the electron and muon channels yielding σEW(\sigma_\mathrm{EW}(Wjj)=)= 6.23±\pm0.12 (stat)±\pm 0.61 (syst) pb per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are -2.3 <cWWW/Λ2<< c_{\mathrm{WWW}}/\Lambda^2 < 2.5 TeV2^{-2}, -8.8 <cW/Λ2<< c_{\mathrm{W}}/\Lambda^2 < 16 TeV2^{-2}, and -45 <cB/Λ2<< c_{\mathrm{B}}/\Lambda^2 < 46 TeV2^{-2}. These results are combined with the CMS EW Zjj analysis, yielding the most stringent limit to date on the cWWWc_{\mathrm{WWW}} coupling: -1.8 <cWWW/Λ2<< c_{\mathrm{WWW}}/\Lambda^2 < 2.0 TeV2^{-2}

    Search for charged Higgs bosons in the H±^{\pm} \to τ±ντ\tau^{\pm}\nu_\tau decay channel in proton-proton collisions at s=\sqrt{s} = 13 TeV

    Get PDF
    A search is presented for charged Higgs bosons in the H±τ±ντ\mathrm{H}^{\pm} \to \tau^{\pm}\nu_\tau decay mode in the hadronic final state and in final states with an electron or muon. The search is based on proton-proton collision data recorded by the CMS experiment in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb1^{-1}. The results agree with the background expectation from the standard model. Upper limits at 95% confidence level are set on the production cross section times branching fraction to τ±ντ\tau^{\pm}\nu_\tau for an H± \mathrm{H}^{\pm} in the mass range of 80 GeV to 3 TeV, including the region near the top quark mass. The observed limit ranges from 6 pb at 80 GeV to 5 fb at 3 TeV. The limits are interpreted in the context of the minimal supersymmetric standard model mhmod-{m_{\mathrm{h}}^\text{mod-}} scenario.A search is presented for charged Higgs bosons in the H±^{±} → τ±^{±}ντ_{τ} decay mode in the hadronic final state and in final states with an electron or a muon. The search is based on proton-proton collision data recorded by the CMS experiment in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb1^{−1}. The results agree with the background expectation from the standard model. Upper limits at 95% confidence level are set on the production cross section times branching fraction to τ±^{±}ντ_{τ} for an H±^{±} in the mass range of 80GeV to 3TeV, including the region near the top quark mass. The observed limit ranges from 6 pb at 80 GeV to 5 fb at 3 TeV. The limits are interpreted in the context of the minimal supersymmetric standard model mhhod_{h}^{hod −} scenario.A search is presented for charged Higgs bosons in the H±^{\pm} \to τ±ντ\tau^{\pm}\nu_\tau decay mode in the hadronic final state and in final states with an electron or muon. The search is based on proton-proton collision data recorded by the CMS experiment in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb1^{-1}. The results agree with the background expectation from the standard model. Upper limits at 95% confidence level are set on the production cross section times branching fraction to τ±ντ\tau^{\pm}\nu_\tau for an H±^{\pm} in the mass range of 80 GeV to 3 TeV, including the region near the top quark mass. The observed limit ranges from 6 pb at 80 GeV to 5 fb at 3 TeV. The limits are interpreted in the context of the minimal supersymmetric standard model mhmodm_\mathrm{h}^\mathrm{mod-} scenario

    Search for W boson decays to three charged pions

    No full text
    For the first time, a search for the rare decay of the W boson to three charged pions has been performed. Proton-proton collision data recorded by the CMS experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 77.3 fb1^{-1}, have been analyzed. No significant excess is observed above the background expectation. An upper limit of 1.01×\times106^{-6} is set at 95% confidence level on the branching fraction of the W boson to three charged pions. This provides a strong motivation for theoretical calculations of this branching fraction

    Constraints on anomalous HVVHVV couplings from the production of Higgs bosons decaying to τ\tau lepton pairs

    No full text
    corecore