A Search for Selectrons and Squarks at HERA

Data from electron-proton collisions at a center-of-mass energy of 300 GeV are used for a search for selectrons and squarks within the framework of the minimal supersymmetric model. The decays of selectrons and squarks into the lightest supersymmetric particle lead to final states with an electron and hadrons accompanied by large missing energy and transverse momentum. No signal is found and new bounds on the existence of these particles are derived. At 95% confidence level the excluded region extends to 65 GeV for selectron and squark masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure

Energy Flow in the Hadronic Final State of Diffractive and Non-Diffractive Deep-Inelastic Scattering at HERA

An investigation of the hadronic final state in diffractive and non--diffractive deep--inelastic electron--proton scattering at HERA is presented, where diffractive data are selected experimentally by demanding a large gap in pseudo --rapidity around the proton remnant direction. The transverse energy flow in the hadronic final state is evaluated using a set of estimators which quantify topological properties. Using available Monte Carlo QCD calculations, it is demonstrated that the final state in diffractive DIS exhibits the features expected if the interaction is interpreted as the scattering of an electron off a current quark with associated effects of perturbative QCD. A model in which deep--inelastic diffraction is taken to be the exchange of a pomeron with partonic structure is found to reproduce the measurements well. Models for deep--inelastic $ep$ scattering, in which a sizeable diffractive contribution is present because of non--perturbative effects in the production of the hadronic final state, reproduce the general tendencies of the data but in all give a worse description.Comment: 22 pages, latex, 6 Figures appended as uuencoded fil

Jets and energy flow in photon-proton collisions at HERA

Properties of the hadronic final state in photoproduction events with large transverse energy are studied at the electron-proton collider HERA. Distributions of the transverse energy, jets and underlying event energy are compared to \overline{p}p data and QCD calculations. The comparisons show that the \gamma p events can be consistently described by QCD models including -- in addition to the primary hard scattering process -- interactions between the two beam remnants. The differential jet cross sections d\sigma/dE_T^{jet} and d\sigma/d\eta^{jet} are measured

Разработка интерактивной моделирующей системы технологии низкотемпературной сепарации газа

We present a study of J ψ meson production in collisions of 26.7 GeV electrons with 820 GeV protons, performed with the H1-detector at the HERA collider at DESY. The J ψ mesons are detected via their leptonic decays both to electrons and muons. Requiring exactly two particles in the detector, a cross section of σ(ep → J ψ X) = (8.8±2.0±2.2) nb is determined for 30 GeV ≤ W γp ≤ 180 GeV and Q 2 ≲ 4 GeV 2 . Using the flux of quasi-real photons with Q 2 ≲ 4 GeV 2 , a total production cross section of σ ( γp → J / ψX ) = (56±13±14) nb is derived at an average W γp =90 GeV. The distribution of the squared momentum transfer t from the proton to the J ψ can be fitted using an exponential exp(− b ∥ t ∥) below a ∥ t ∥ of 0.75 GeV 2 yielding a slope parameter of b = (4.7±1.9) GeV −2

A Measurement of the Proton Structure Function F ⁣2(x,Q2)F_{\!2}(x,Q^2)

A measurement of the proton structure function $F_{\!2}(x,Q^2)$ is reported for momentum transfer squared $Q^2$ between 4.5 $GeV^2$ and 1600 $GeV^2$ and for Bjorken $x$ between $1.8\cdot10^{-4}$ and 0.13 using data collected by the HERA experiment H1 in 1993. It is observed that $F_{\!2}$ increases significantly with decreasing $x$, confirming our previous measurement made with one tenth of the data available in this analysis. The $Q^2$ dependence is approximately logarithmic over the full kinematic range covered. The subsample of deep inelastic events with a large pseudo-rapidity gap in the hadronic energy flow close to the proton remnant is used to measure the "diffractive" contribution to $F_{\!2}$.Comment: 32 pages, ps, appended as compressed, uuencoded fil

Das AKTIN-Notaufnahmeregister – kontinuierlich aktuelle Daten aus der Akutmedizin

Zusammenfassung Hintergrund Die Notfallversorgung befindet sich im Umbruch. In Notaufnahmen werden Patienten ausgehend von Symptomen und Dringlichkeit versorgt; dies bildet sich jedoch in den etablierten Routinedaten der gesetzlichen Sozialversicherung nicht ab. Ziel des AKTIN-Projekts war der Aufbau einer datenschutzkonformen Registerinfrastruktur zur Nutzung von klinischen Routinedaten aus Notaufnahmen. Methoden Über eine standardisierte Schnittstelle werden aus den verschiedenen Dokumentationssystemen kontinuierlich Daten der Notaufnahmebehandlung in ein lokales Data Warehouse exportiert. Dort stehen sie sowohl für lokale Nutzungen, wie interne Berichte und Qualitätsmanagement, als auch gleichzeitig datenschutzkonform für multizentrische Auswertungen zur Verfügung. Anhand der Registerpopulation wird die Ersteinschätzung sowie die Erhebung von Vitalparametern in Abhängigkeit von Vorstellungsgründen für einen 12-Monats-Zeitraum analysiert. Ergebnisse Für den Zeitraum 04/2018 bis 03/2019 wurden 436.149 gültige Fälle aus 15 Notaufnahmen übermittelt. In 86,0 % der Fälle ist eine Ersteinschätzung dokumentiert. Diese fand in 70,5 % innerhalb von 10 min nach Ankunft des Patienten statt. In 10 Kliniken wird regelhaft (82,3 %) ein Vorstellungsgrund erfasst. Die Erfassung von Vitalparametern variiert plausibel zwischen den Vorstellungsgründen. Schlussfolgerung Das AKTIN-Notaufnahmeregister bietet einen zeitnahen Einblick in das Versorgungsgeschehen der Notaufnahmen ohne zusätzlichen Dokumentationsaufwand und unabhängig vom primären IT-System, Kostenträger, Fallart und Abrechnungsmodus. Die Vorgaben des Gemeinsamen Bundesausschusses zur Ersteinschätzung werden weitgehend umgesetzt. Durch die Etablierung von standardisierten Vorstellungsgründen werden symptombasierte Analysen und Gesundheitssurveillance ermöglicht. </jats:sec