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[en] The process γγ→l⁺ l^- is highly suppressed when the total angular momentum of the two colliding photons is zero so that it cannot be used for luminosity determination. This configuration, however is needed for Higgs production at a photon collider. It will be shown that the process γγ→l⁺ l^- γ can be used in this case to measure the luminosity of a collider with a precision that is good enough not to limit the error on the partial decay width Γ(H →γγ). (orig.)

[en] The process pe ^±→pe^±γ with the photon emitted along the electron beam axis is used for luminosity measurement at HERA. In this paper the process is calculated including one-loop QED radiative corrections. In the ZEUS experiment, both the electron and the photon can be detected. Therefore both photon and electron spectra with and without the γ-e coincidence are analyzed. We also calculate the process pe^±→pe ^±l^-l⁺ which contributes to the background in the electron tagger. (orig.)

[en] The process pe^± → pe^±γ with the photon emitted along the electron beam axis is used for luminosity measurement at HERA. In this paper the process is calculated including one-loop QED radiative corrections. In the ZEUS experiment, both the electron and the photon can be detected. Therefore both photon and electron spectra with and without the γ-e coincidence are analyzed. We also calculate the process pe^± → pe^±l^-l⁺ which contributes to the background in the electron tagger. (orig.)

[en] The paper discusses the history of planning the city of Birobidzhan. Each consecutive Urban Master Plan continued its predecessor; however, none of the plans contained interesting architectural and compositional solutions. The environmental conditions (which are not to be ignored in urban planning) result in unfavorable geotechnical and environmental impacts. The left-bank part of the city is located in the floodplain and straddles an embankment prone to waterlogging. Embankment height varies from 1 to 5 meters. Embankment is prone to erosion. The right-bank part of the city lies on a slope; the environmental conditions here are better. Birobidzhan has an explicitly monsoon climate; the street layout prevents self-purification of the atmosphere. Environmental constraints are defined for the City of Birobidzhan; an environmental framework is proposed. (paper)

[en] The Higgs boson was postulated nearly five decades ago within the framework of the standard model of particle physics and has been the subject of numerous searches at accelerators around the world. Its discovery would verify the existence of a complex scalar field thought to give mass to three of the carriers of the electroweak force - the W⁺, W^-, and Z⁰ bosons - as well as to the fundamental quarks and leptons. The CMS Collaboration has observed, with a statistical significance of five standard deviations, a new particle produced in proton-proton collisions at the Large Hadron Collider at CERN. The evidence is strongest in the di-photon and four-lepton (electrons and/or muons) final states, which provide the best mass resolution in the CMS detector. The probability of the observed signal being due to a random fluctuation of the background is about 1 in 3 * 10⁶. The new particle is a boson with spin not equal to 1 and has a mass of about 125 giga-electron volts. Although its measured properties are, within the uncertainties of the present data, consistent with those expected of the Higgs boson, more data are needed to elucidate the precise nature of the new particle. (authors)

[en] The Compact Linear Collider (CLIC) is an option for a future e"+e"- collider operating at centre-of-mass energies up to 3 TeV, providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper is the first comprehensive presentation of the Higgs physics reach of CLIC operating at three energy stages: √(s) = 350 GeV, 1.4 and 3 TeV. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung (e"+e"- → ZH) and WW-fusion (e"+e"- → Hν_e anti ν_e), resulting in precise measurements of the production cross sections, the Higgs total decay width Γ_H, and model-independent determinations of the Higgs couplings. Operation at √(s) > 1 TeV provides high-statistics samples of Higgs bosons produced through WW-fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes e"+e"- → t anti tH and e"+e"- → HHν_e anti ν_e allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of the precision achievable with Higgs measurements at CLIC and describes the interpretation of these measurements in a global fit. (orig.)