13 research outputs found

    The corrosion damage mechanisms of the gas pipelines in the Republic of Sakha (Yakutia)

    No full text
    The article provides examples of critical damage to a long-running gas pipeline on the territory of the Republic of Sakha (Yakutia), which arose as a result of the development of corrosion processes, discusses the mechanisms and scenarios for the development of corrosion damage in the cryolithozone conditions. Considering the processes and mechanisms, they continue for a long period of time., an increase in the number of damages to a gas main pipeline due to corrosive degradation is expected in the near future. The stage of diffuse damage during long-term operation is confirmed by the increasing loss of working capacity due to corrosion damage in the last 25 years of the pipeline operation

    Diffractive Dijet Production with a Leading Proton in ep Collisions at HERA

    No full text
    The cross section of the diffractive process e^+p -> e^+Xp is measured at a centre-of-mass energy of 318 GeV, where the system X contains at least two jets and the leading final state proton p is detected in the H1 Very Forward Proton Spectrometer. The measurement is performed in photoproduction with photon virtualities Q^2 <2 GeV^2 and in deep-inelastic scattering with 4 GeV^2<Q^2<80 GeV^2. The results are compared to next-to-leading order QCD calculations based on diffractive parton distribution functions as extracted from measurements of inclusive cross sections in diffractive deep-inelastic scattering

    Measurement of Jet Production Cross Sections in Deep-inelastic ep Scattering at HERA

    No full text
    A precision measurement of jet cross sections in neutral current deep-inelastic scattering for photon virtualities 5.5<Q2<80GeV25.5<Q^2<80\,{\rm GeV}^2 and inelasticities 0.2<y<0.60.2<y<0.6 is presented, using data taken with the H1 detector at HERA, corresponding to an integrated luminosity of 290pb1290\,{\rm pb}^{-1}. Double-differential inclusive jet, dijet and trijet cross sections are measured simultaneously and are presented as a function of jet transverse momentum observables and as a function of Q2Q^2. Jet cross sections normalised to the inclusive neutral current DIS cross section in the respective Q2Q^2-interval are also determined. Previous results of inclusive jet cross sections in the range 150<Q2<15000GeV2150<Q^2<15\,000\,{\rm GeV}^2 are extended to low transverse jet momenta 5<PTjet<7GeV5<P_{T}^{\rm jet}<7\,{\rm GeV}. The data are compared to predictions from perturbative QCD in next-to-leading order in the strong coupling, in approximate next-to-next-to-leading order and in full next-to-next-to-leading order. Using also the recently published H1 jet data at high values of Q2Q^2, the strong coupling constant αs(MZ)\alpha_s(M_Z) is determined in next-to-leading order.A precision measurement of jet cross sections in neutral current deep-inelastic scattering for photon virtualities 5.5<Q2<80GeV25.5<Q^2<80\,{\rm GeV}^2 and inelasticities 0.2<y<0.60.2<y<0.6 is presented, using data taken with the H1 detector at HERA, corresponding to an integrated luminosity of 290pb1290\,{\rm pb}^{-1}. Double-differential inclusive jet, dijet and trijet cross sections are measured simultaneously and are presented as a function of jet transverse momentum observables and as a function of Q2Q^2. Jet cross sections normalised to the inclusive neutral current DIS cross section in the respective Q2Q^2-interval are also determined. Previous results of inclusive jet cross sections in the range 150<Q2<15000GeV2150<Q^2<15\,000\,{\rm GeV}^2 are extended to low transverse jet momenta 5<PTjet<7GeV5<P_{T}^{\rm jet}<7\,{\rm GeV}. The data are compared to predictions from perturbative QCD in next-to-leading order in the strong coupling, in approximate next-to-next-to-leading order and in full next-to-next-to-leading order. Using also the recently published H1 jet data at high values of Q2Q^2, the strong coupling constant αs(MZ)\alpha_s(M_Z) is determined in next-to-leading order.A precision measurement of jet cross sections in neutral current deep-inelastic scattering for photon virtualities 5.5<Q2<80GeV25.5<Q^2 <80\,\mathrm {GeV}^2 and inelasticities 0.2<y<0.60.2<y<0.6 is presented, using data taken with the H1 detector at HERA, corresponding to an integrated luminosity of 290pb1290\,\mathrm {pb}^{-1} . Double-differential inclusive jet, dijet and trijet cross sections are measured simultaneously and are presented as a function of jet transverse momentum observables and as a function of Q2Q^2 . Jet cross sections normalised to the inclusive neutral current DIS cross section in the respective Q2Q^2 -interval are also determined. Previous results of inclusive jet cross sections in the range 150<Q2<15,000GeV2150<Q^2 <15{,}000\,\mathrm {GeV}^2 are extended to low transverse jet momenta 5<PTjet<7GeV5<P_\mathrm{T}^\mathrm{jet} <7\,\mathrm {GeV} . The data are compared to predictions from perturbative QCD in next-to-leading order in the strong coupling, in approximate next-to-next-to-leading order and in full next-to-next-to-leading order. Using also the recently published H1 jet data at high values of Q2Q^2 , the strong coupling constant αs(MZ)\alpha _s(M_Z) is determined in next-to-leading order

    Colombeau generalized functions on manifolds

    No full text
    Eduard NigschZsfassung in dt. SpracheWien, Techn. Univ. u. Univ., Dipl.-Arb., 2006OeBB(VLID)161012

    Exclusive ρ0\rho^0 Meson Photoproduction with a Leading Neutron at HERA

    No full text
    A first measurement is presented of exclusive photoproduction of ρ0\rho^0 mesons associated with leading neutrons at HERA. The data were taken with the H1 detector in the years 20062006 and 20072007 at a centre-of-mass energy of s=319\sqrt{s}=319 GeV and correspond to an integrated luminosity of 1.161.16 pb1^{-1}. The ρ0\rho^0 mesons with transverse momenta pT0.35p_T0.35, are detected in the Forward Neutron Calorimeter. The phase space of the measurement is defined by the photon virtuality Q2<2Q^2 < 2 GeV2^2, the total energy of the photon-proton system 20<Wγp<10020 < W_{\gamma p} < 100 GeV and the polar angle of the leading neutron θn<0.75\theta_n < 0.75 mrad. The cross section of the reaction γpρ0nπ+\gamma p \to \rho^0 n \pi^+ is measured as a function of several variables. The data are interpreted in terms of a double peripheral process, involving pion exchange at the proton vertex followed by elastic photoproduction of a ρ0\rho^0 meson on the virtual pion. In the framework of one-pion-exchange dominance the elastic cross section of photon-pion scattering, σel(γπ+ρ0π+)\sigma^{\rm el}(\gamma\pi^+ \to \rho^0\pi^+), is extracted. The value of this cross section indicates significant absorptive corrections for the exclusive reaction γpρ0nπ+\gamma p\to\rho^0 n \pi^+

    Measurement of Dijet Production in Diffractive Deep-Inelastic ep Scattering at HERA

    No full text
    A measurement is presented of single- and double-differential dijet cross sections in diffractive deep-inelastic epep scattering at HERA using data collected by the H1 experiment corresponding to an integrated luminosity of 290 pb^{-1}. The investigated phase space is spanned by the photon virtuality in the range of 4<Q^{2}<100 GeV^{2} and by the fractional proton longitudinal momentum loss x_pom<0.03. The resulting cross sections are compared with next-to-leading order QCD predictions based on diffractive parton distribution functions and the value of the strong coupling constant is extracted

    Diffractive Dijet Production with a Leading Proton in ep\it ep Collisions at HERA

    No full text
    The cross section of the diffractive process e+pe+Xp\it e^{+}p → e^{+}X p is measured at a centre-of- mass energy of 318 GeV, where the system X contains at least two jets and the leading final state proton p\it p is detected in the H1 Very Forward Proton Spectrometer. The measurement is performed in photoproduction with photon virtualities Q2<2GeV2\it Q^{2} < 2 GeV^{2} and in deep-inelastic scattering with 4GeV2<Q2<80GeV2\it 4 GeV^{2} < Q^{2} < 80 GeV^{2}. The results are compared to next-to-leading order QCD calculations based on diffractive parton distribution functions as extracted from measurements of inclusive cross sections in diffractive deep-inelastic scattering

    Measurement of Multijet Production in epep Collisions at High Q2Q^2 and Determination of the Strong Coupling αs\alpha_s

    No full text
    Inclusive jet, dijet and trijet differential cross sections are measured in neutral current deep-inelastic scattering for exchanged boson virtualities 150 < Q^2 < 15000 GeV^2 using the H1 detector at HERA. The data were taken in the years 2003 to 2007 and correspond to an integrated luminosity of 351 pb^{-1}. Double differential Jet cross sections are obtained using a regularised unfolding procedure. They are presented as a function of Q^2 and the transverse momentum of the jet, P_T^jet, and as a function of Q^2 and the proton's longitudinal momentum fraction, Xi, carried by the parton participating in the hard interaction. In addition normalised double differential jet cross sections are measured as the ratio of the jet cross sections to the inclusive neutral current cross sections in the respective Q^2 bins of the jet measurements. Compared to earlier work, the measurements benefit from an improved reconstruction and calibration of the hadronic final state. The cross sections are compared to perturbative QCD calculations in next-to-leading order and are used to determine the running coupling and the value of the strong coupling constant as alpha_s(M_Z) = 0.1165 (8)_exp (38)_{pdf,theo}

    Measurement of Charged Particle Spectra in Deep-Inelastic ep Scattering at HERA

    No full text
    Charged particle production in deep-inelastic ep scattering is measured with the H1 detector at HERA. The kinematic range of the analysis covers low photon virtualities, 5 < Q^2 < 100 GeV^2, and small values of Bjorken-x, 10^{-4} < x < 10^{-2}. The analysis is performed in the hadronic centre-of-mass system. The charged particle densities are measured as a function of pseudorapidity (eta^*) and transverse momentum (p_T^*) in the range 0< \eta^* < 5 and 0< p_T^* < 10$ GeV differentially in x and Q^2. The data are compared to predictions from different Monte Carlo generators implementing various options for hadronisation and parton evolutions. arXi
    corecore