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Abstract in Undetermined Applications of physical bounds for electromagnetic radiators can be used to derive a priori estimates for antenna parameters in terms of the directivity-bandwidth product. These estimates relate the static electric and magnetic polarizability of the radiating structure to its dynamic properties. The results have previously been illustrated for dipole radiators with good aApplications of physical bounds for electromagnetic radiators can be used to derive a priori estimates for antenna parameters in terms of the directivity-bandwidth product. These estimates relate the static electric and magnetic polarizability of the radiating structure to its dynamic properties. The results have previously been illustrated for dipole radiators with good agreement. Here, the bound

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

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

The leptoproduction of J/psi mesons is studied in inelastic reactions for four momentorri transfers 2 < Q(2) < 100GeV(2). The data were taken with the H1 detector at the electron proton collider HERA and correspond to an integrated luminosity of 77 pb(-1). Single differential and double differential cross sections are measured with increased precision compared with previous analyses. New leading o

An analysis of inelastic photoproduction of J/psi mesons is presented using data collected at the ep collider HERA corresponding to an integrated luminosity of above 80 pb(-1), Differential and double I < P-t/psi(2) < differential cross sections are measured in a wide kinematic region: 60 < W-gammap < 260 GeV, 1 p(t,psi)(2) < 60 GeV2 and 0.05 < z < 0.9. where z is the fraction of the energy of the

Popular Abstract in Swedish 75% av alla kemiska reaktioner sker på en yta av något slag. En av anledningarna till detta är att många ytor har en katalytisk effekt. Inom kemins värld är en katalysator något som påskyndar en kemisk reaktion utan att själv förbrukas, och ett tydligt exempel på en katalytiskt aktiv yta är en bilkatalysator, vilken i princip består av en varm metallyta. På denna yta omThis work deals with interpretation of experimental surface spectroscopic data with the aid of first-principle calculations. Surface infrared reflection-absorption spectra as well as spectra from the electron spectroscopic methods photoemission and X-ray absorption are considered. In all cases the surface is modeled by a metal cluster with the same (frozen) geometry as part of the surface. The wo

Popular Abstract in English Globalization and new technologies in transportation and communication have opened the doors for partnerships beyond the national and regional borders, making business survival more complex than ever before. We can see more companies outsourcing different aspects of their business in order to focus on one or a few core competencies, which would potentially gain them morIn this dissertation, we discuss how buyers practice purchasing strategies in an asymmetric power situation favoring suppliers, and how their purchasing strategies practiced impact their purchasing power and buyer-supplier relationships. Organizations enter exchange relationships to access required resources not produced internally, and are exposed to uncertainty from not being able to fully contr

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)

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*

Utbildningsdag för SACO-S arbetsplatsombud tisdag den 2 novemberg 2025-03-24 Nomineringsval av arbetsplatsombud för perioden 1/7 2025 – 30/6 2027 Till Saco-S-rådets arbetsplatsombud Det är dags för nomineringsval av arbetsplatsombud på din institution/enhet för kommande mandat​period 2025-07-01 – 2027-06-30. Inför nominering skall medlemmar som tillhör ett Saco-S-förbund sammankallas till ett möte

https://www.saco.se/globalassets/lokala-akademikerforeningar/statlig/umea-universitet/dokument/arbetsplatsombud---nomineringsblankett-2025-2027.doc - 2026-07-12

På den här sidan samlar vi information som rör arbetet vid Pufendorfinstitutet för våra Teman och Advanced Study Groups. Om ni inte hittar svaret ni söker eller har fler frågor, skriv till oss via contact [at] pi [dot] lu [dot] seInformationen är uppdelad inom följande områdenEkonomi: för svar om kostnadsram, budget och lönekontering samt gästforskare, faktureringsadress och utlägg.Evenemang: för

https://www.pi.lu.se/vad-hander-pa-pufendorfinstitutet/information-vara-grupper - 2026-07-13

I mitt forskningsprojekt har jag studerat generna i ’the major histocompatibility complex’ (MHC). Generna i detta komplex kodar för molekyler som uttrycks på cellytan och dessa molekyler är avgörande för immunförsvarets förmåga att upptäcka och bekämpa patogener (sjukdomsalstrande mikroorganismer, som virus, bakterier och parasiter). Det övergripande syftet i min forskning har varit att undersöka Sex differences in immune responses have been observed across a wide range of animal species, with the generaltendency that males have weaker immune responses than females. These differences are at least partly caused by immune-regulating effects of sex hormones, and have been associated with an increased prevalence of autoimmune disorders in females and with a general tendency for males to be par