3,747 research outputs found

    Extending the Higgs sector: an extra singlet

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    An extension of the Standard Model with an additional Higgs singlet is analyzed. Bounds on singlet admixture in 125 GeV h boson from electroweak radiative corrections and data on h production and decays are obtained. Possibility of double h production enhancement at 14 TeV LHC due to heavy higgs contribution is considered.Comment: 18 pages, 7 figures. v2: one equation added; references received after the publication of v1 are adde

    New Physics at 1 TeV?

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    If decays of a heavy particle S are responsible for the diphoton excess with invariant mass 750 GeV observed at the 13 TeV LHC run, it can be easily accomodated in the Standard Model. Two scenarios are considered: production in gluon fusion through a loop of heavy isosinglet quark(s) and production in photon fusion through a loop of heavy isosinglet leptons. In the second case many heavy leptons are needed or/and they should have large electric charges in order to reproduce experimental data on σ(pp→SX)⋅Br(S→γγ)\sigma(pp \to SX) \cdot \mathrm{Br}(S \to \gamma \gamma).Comment: 7 pages, 4 figures, 1 tabl

    Chemistry-climate model SOCOL: a validation of the present-day climatology

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    In this paper we document 'SOCOL', a new chemistry-climate model, which has been ported for regular PCs and shows good wall-clock performance. An extensive validation of the model results against present-day climate data obtained from observations and assimilation data sets shows that the model describes the climatological state of the atmosphere for the late 1990s with reasonable accuracy. The model has a significant temperature bias only in the upper stratosphere and near the tropopause at high latitudes. The latter is the result of the rather low vertical resolution of the model near the tropopause. The former can be attributed to a crude representation of radiation heating in the middle atmosphere. A comparison of the simulated and observed link between the tropical stratospheric structure and the strength of the polar vortex shows that in general, both observations and simulations reveal a higher temperature and ozone mixing ratio in the lower tropical stratosphere for the case with stronger Polar night jet (PNJ) and slower Brewer-Dobson circulation as predicted by theoretical studies

    Chemistry-climate model SOCOL: a validation of the present-day climatology

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    International audienceIn this paper we document ''SOCOL'', a new chemistry-climate model, which has been ported for regular PCs and shows good wall-clock performance. An extensive validation of the model results against present-day climate obtained from observations and assimilation data sets shows that the model describes the climatological state of the atmosphere for the late 1990s with reasonable accuracy. The model has a significant temperature bias only in the upper stratosphere and near the tropopause in the tropics and high latitudes. The latter is the result of the rather low vertical resolution of the model near the tropopause. The former can be attributed to a crude representation of the radiation heating in the middle atmosphere. A comparison of the simulated and observed link between the tropical stratospheric structure and the strength of the polar vortex shows that in general, both observations and simulations reveal a higher temperature and ozone mixing ratio in the lower tropical stratosphere for the case with stronger Polar night jet (PNJ) as predicted by theoretical studies

    Once more on extra quark-lepton generations and precision measurements

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    Precision measurements of ZZ-boson parameters and WW-boson and tt-quark masses put strong constraints on non SU(2)×U(1)SU(2)\times U(1) singlet New Physics. We demonstrate that one extra generation passes electroweak constraints even when all new particle masses are well above their direct mass bounds.Comment: Dedicated to L.B. Okun's 80th birthda

    Nonlinear acoustic waves in channels with variable cross sections

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    The point symmetry group is studied for the generalized Webster-type equation describing non-linear acoustic waves in lossy channels with variable cross sections. It is shown that, for certain types of cross section profiles, the admitted symmetry group is extended and the invariant solutions corresponding to these profiles are obtained. Approximate analytic solutions to the generalized Webster equation are derived for channels with smoothly varying cross sections and arbitrary initial conditions.Comment: Revtex4, 10 pages, 2 figure. This is an enlarged contribution to Acoustical Physics, 2012, v.58, No.3, p.269-276 with modest stylistic corrections introduced mainly in the Introduction and References. Several typos were also correcte

    pppp scattering at the LHC with the lepton pair production and one proton tagging

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    Analytical formulas for the cross section of the reaction pp→p+ℓ+ℓ−+Xpp \to p + \ell^+ \ell^- + X are presented. Fiducial cross sections are compared with those measured recently by the ATLAS collaboration.Comment: 12 pages, 1 figur

    Weak interaction corrections to muon pair production via the photon fusion at the LHC

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    Analytical formulas describing the correction due to the ZZ boson exchange to the cross section of the reaction pp→pμ+μ−Xpp\rightarrow p\mu^+\mu^- X are presented. When the invariant mass of the produced muon pair W≳150 GeVW\gtrsim 150~\text{GeV} and its total transverse momentum is large, the correction is of the order of 20%.Comment: 17 pages, 5 figure
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