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Dijet cross sections as functions of several jet observables are measured in photoproduction using the HI detector at HERA. The data sample comprises e(+)p data with an integrated luminosity of 319 pb(-1). Jets are selected using the inclusive k(perpendicular to) algorithm with a minimum transverse energy of 25 GeV for the leading jet. The phase space covers longitudinal proton momentum fraction x

Multi-electron production is studied at high electron transverse momentum in positron- and electron-proton collisions using the H1 detector at HERA. The data correspond to an integrated luminosity of 115 pb(-1). Di-electron and tri-electron event yields are measured. Cross sections are derived in a restricted phase space region dominated by photon-photon collisions. In general good agreement is fo

Dijet production in deep inelastic ep scattering is investigated in the region of low values of the Bjorken-variable x (10(-4) < x < 10(-2)) and low photon virtualities Q(2) (5 < Q(2) < 100 GeV2). The measured dijet cross sections are compared with perturbative QCD calculations in next-to-leading order. For most dijet variables studied, these calculations can provide a reasonable description of th

Popular Abstract in Swedish Teorin för den starka kraften, kvantkromodynamik eller QCD, behandlas här med både perturbativa och icke-perturbativa metoder. Speciellt produktions- och hadroniseringsdynamiken hos tunga partiklar studeras. Dessa partiklar innefattar tunga kvarkar (charm, botten och top), gaugebosoner, leptokvarkar och supersymmetriska partiklar. När tunga långlivade kvarkar (d.v.s. cIn this thesis the phenomenology of Quantum Chromo Dynamics (QCD) is studied in a variety of circumstances from both perturbative and non-perturbative perspectives. The main emphasis is on the production and hadronization of heavy particles, specifically heavy quarks, gauge bosons, leptoquarks and supersymmetric particles. In the hadroproduction of long-lived heavy quarks (i.e. charm and bottom)

Using the deep inelastic e(+) p and e(-) p charged and neutral current scattering cross sections previously published, a combined electroweak and QCD analysis is performed to determine electroweak parameters accounting for their correlation with parton distributions. The data used have been collected by the HI experiment in 1994-2000 and correspond to an integrated luminosity of 117.2 pb(-1). A me

Moments of the hadronic invariant mass and of the lepton energy spectra in semileptonic B decays have been determined with the data recorded by the DELPHI detector at LEP. From measurements of the inclusive b-hadron semileptonic decays, and imposing constraints from other measurements on b- and c-quark masses, the first three moments of the lepton energy distribution and of the hadronic mass distr

Results on diffractive photoproduction of psi(2S) mesons are presented using data collected between 1996 and 2000 with the H1 detector at the HERA ep collider. The data correspond to an integrated luminosity of 77 pb(-1). The energy dependence of the diffractive psi(2S) cross section is found to be similar to or possibly somewhat steeper than that for J/psi mesons. The dependences of the elastic a

A search for events with a high-energy isolated electron or muon and missing transverse momentum has been performed at the electron-proton collider HERA using an integrated luminosity of 13.6 pb(-1) in e(-) p scattering and 104.7 pb(-1) in e(+) p scattering. Within the Standard Model such events are expected to be mainly due to W boson production with subsequent leptonic decay. In e(-) p interacti

A search for single top quark production is performed in e(+/-) pcollisions at HERA. The search exploits data corresponding to an integrated luminosity of 118.3 pb(-1). A model for the anomalous production of top quarks in a flavour changing neutral current process involving a tugamma coupling is investigated. Decays of top quarks into a b quark and a W boson are considered in the leptonic and the

A search for contributions to the reaction ep --> epi(0)N* from photon-odderon fusion in the photoproduction regime at HERA is reported, at an average photon-proton centre-of-mass energy = 215 GeV. The measurement proceeds via detection of the pi(0) decay photons, a leading neutron from the N* decay, and the scattered electron. No pi(0) signal is observed and an upper limit on the cross sectio

Triple differential dijet cross sections in e(+/-)p interactions are presented in the region of photon virtualities 2 < Q(2) < 80 GeV2, inelasticities 0.1 < y < 0.85, jet transverse energies E*(T1) > 7GeV, E*(T2) > 5 GeV, and pseudorapidities - 2.5 < η(1)*, η(2)* < 0. The measurements are made in the gamma*p centre-of-mass frame, using an integrated luminosity of 57 pb(-1). The data are compared w

Background: Relenza represents the first neuraminidase inhibitor (NI), a class of drugs that also includes the drug Tamiflu. Although heralded as breakthrough treatments in influenza, NI efficacy has remained highly controversial. A key unsettled question is why the US Food and Drug Administration (FDA) has approved more cautious efficacy statements in labelling than European regulators for both dBackgroundRelenza represents the first neuraminidase inhibitor (NI), a class of drugs that also includes the drug Tamiflu. Although heralded as breakthrough treatments in influenza, NI efficacy has remained highly controversial. A key unsettled question is why the United States Food and Drug Administration (FDA) has approved more cautious efficacy statements in labelling than European regulators f

Lera består utav små finkorniga lermineraler, vilka utgörs till stor del av elektrostatiskt laddade nanopartiklar, även kallade lerplattor. En lerplatta har en tjocklek på en miljarddels meter och dess diameter kan variera alltifrån fem till tusen gånger större än tjockleken, vilket kan jämföras med ett A4-ark, där kortsidan är tusen gånger större än tjockleken. Denna storleksskillnad ger upphov tClay minerals consist of anisotropic nanoplatelets where the majority of the clay minerals are highly charged, and thus, swell in aqueous solution. The structure and swelling depend on the type of clay mineral, and also on the ionic composition, and temperature. The natural clay mineral montmorillonite have been studied both theoretically and experimentally. Theoretically, coarse-grained models ha

The inclusive production of D*+/-(2010) mesons in deep-inelastic scattering is studied with the HI detector at HERA. In the kinematic region 1 < Q(2) < 100 GeV2 and 0.05 < y < 0.7 an e(+) p cross section for inclusive D*+/- meson production of 8.50 +/- 0.42(stat.)(-100)(+1.21)(syst.) nb is measured in the visible range p(tD*) > 1.5 GeV and eta(D*) < 1.5. Single and double differential inclusive D*

In this paper I address two concerns with Kelly Trogdon’s grounding mechanism view, i.e. the idea that metaphysical explanation can be modeled on causal-mechanical explanation. The first concern threatens to undermine the unity that grounding-mechanical explanations imposes on metaphysical explanation; and the second concern requires the grounding mechanic to put forth a formal condition on ground

BackgroundThe Parkinson's Disease (PD) Home Diary (HD) is a common clinical outcome measure, but studies show only fair agreement between clinical observer and patient assessments, with no significant improvement after patient training.ObjectivesTo investigate the agreement between a clinical observer and relatives of PD patients when assessing the patient's motor status in the HD. Agreement was a

Retshjælpsprojektet er et retssociologisk forskningsprojekt, der undersøger borgernes adgang til hjælp og juridisk bistand. Retshjælpsprojektet bidrager med ny viden ved at inddrage borgernes perspektiv i et hidtil uset omfang, da deres perspektiv på adgang til hjælp og juridisk bistand, herunder retshjælp, er helt centralt for at kunne kortlægge de faktorer, der påvirker borgernes vej til hjælpen

The Svalbard Rock Ptarmigan, Lagopus muta hyperborea, is the only year-round resident terrestrial bird in the high Arctic. Many of the physiological and morphological adaptations permitting its winter endurance in this harsh environment are well understood. However, it remains unknown how the conspicuous moult from a greyish brown summer to a white winter plumage, and any underlying changes in pluThe Svalbard Rock Ptarmigan, Lagopus muta hyperborea, is the only year-round resident terrestrial bird in the high Arctic. Many of the physiological and morphological adaptations permitting its winter endurance in this harsh environment are well understood. However, it remains unknown how the conspicuous moult from a greyish brown summer to a white winter plumage, and any underlying changes in plu