Limits on diffuse fluxes of high energy extraterrestrial neutrinos with the AMANDA-B10 detector

Data from the AMANDA-B10 detector taken during the austral winter of 1997 have been searched for a diffuse flux of high energy extraterrestrial muon-neutrinos, as predicted from, e.g., the sum of all active galaxies in the universe. This search yielded no excess events above those expected from the background atmospheric neutrinos, leading to upper limits on the extraterrestrial neutrino flux. For an assumed E^-2 spectrum, a 90% classical confidence level upper limit has been placed at a level E^2 Phi(E) = 8.4 x 10^-7 GeV cm^-2 s^-1 sr^-1 (for a predominant neutrino energy range 6-1000 TeV) which is the most restrictive bound placed by any neutrino detector. When specific predicted spectral forms are considered, it is found that some are excluded.Comment: Submitted to Physical Review Letter

DASC-PM v1.0 : ein Vorgehensmodell für Data-Science-Projekte

Das Thema Data Science hat in den letzten Jahren in vielen Organisationen stark an Aufmerksamkeit gewonnen. Häufig herrscht jedoch weiterhin große Unklarheit darüber, wie diese Disziplin von anderen abzugrenzen ist, welche Besonderheiten der Ablauf eines Data-Science-Projekts besitzt und welche Kompetenzen vorhanden sein müssen, um ein solches Projekt durchzuführen. In der Hoffnung, einen kleinen Beitrag zur Beseitigung dieser Unklarheiten leisten zu können, haben wir von April 2019 bis Februar 2020 in einer offenen und virtuellen Arbeitsgruppe mit Vertretern aus Theorie und Praxis das vorliegende Dokument erarbeitet, in dem ein Vorgehensmodell für Data-Science-Projekte beschrieben wird – das Data Science Process Model (DASC-PM). Ziel war es dabei nicht, neue Herangehensweisen zu entwickeln, sondern viel-mehr, vorhandenes Wissen zusammenzutragen und in geeigneter Form zu strukturieren. Die Ausarbeitung ist als Zusammenführung der Erfahrung sämtlicher Teilnehmerinnen und Teilnehmer dieser Arbeitsgruppe zu verstehen

Предварительное исследование применения системы спектрального регулирования для ТВС реактора ВВЭР-1000

Повышение топливных характеристик ядерных реакторов за счет применения концепции управления спектральным сдвигом (SSC) вместо традиционных методов, основанных на поглощении, является многообещающим подходом к снижению стоимости топливного цикла и увеличению использования топливных ресурсов (U, Pu). В данной работе было проведено исследование применения химического метода SSC для модели топливной сборки ВВЭР-1000 с низкообогащенным ураном, в которой контроль реактивности осуществляется путем изменения доли D2O относительно легководного замедлителя (D2O/H2O), и сравнение с поглощающими материалами, в которых содержится 600 ppm H3BO3 и 4,0 мас.% Gd2O3

Perioperative blood transfusion: the role of allogenous and autologous transfusions, and pharmacological agents.

The decision to transfuse patients perioperatively is made on an individual basis and should consider factors such as duration and severity of anaemia, symptoms, physiological parameters and comorbidities. Autologous blood transfusion has the benefit of avoiding some of the immunological and infective complications associated with allogenic blood transfusion. Pharmacological agents as well as anaesthetic and surgical techniques have a role in avoiding the need for blood transfusion

Results from the AMANDA neutrino telescope

We review recent results from AMANDA on the search for cosmic point sources of neutrinos, both in the diffuse and point-like channels. Assuming a E-2 spectral shape of the neutrino energy at the source, we derive limits on the diffuse \u3bd\u3bc flux as well as in the all-flavour diffuse flux from the cascade search. We report limits on selected point sources as well as on GRB searches. We present results on primary cosmic CR composition in the range 3c100 TeV-PeV obtained with the help of the SPASE air shower array run in coincidence with AMANDA. \ua9 2004 Elsevier B.V. All rights reserved

Measurement of the cosmic ray composition at the knee with the SPASE-2/AMANDA-B10 detectors

The mass composition of high-energy cosmic rays at energies above 10 15 eV can provide crucial information for the understanding of their origin. Air showers were measured simultaneously with the SPASE-2 air shower array and the AMANDA-B10 Cherenkov telescope at the South Pole. This combination has the advantage to sample almost all high-energy shower muons and is thus a new approach to the determination of the cosmic ray composition. The change in the cosmic ray mass composition was measured versus existing data from direct measurements at low energies. Our data show an increase of the mean log atomic mass 〈ln A 〉 by about 0.8 between 500 TeV and 5 PeV. This trend of an increasing mass through the “knee” region is robust against a variety of systematic effects

Flux limits on ultra high energy neutrinos with AMANDA-B10

Data taken during 1997 with the AMANDA-B10 detector are searched for a diffuse flux of neutrinos of all flavors with energies above 1016eV. At these energies the Earth is opaque to neutrinos, and thus neutrino induced events are concentrated at the horizon. The background are large muon bundles from down-going atmospheric air shower events. No excess events above the background expectation are observed and a neutrino flux following E-2, with an equal mix of all flavors, is limited to E2φ(1015eV < E < 3 × 1018eV) ≤ 0.99 × 10-6GeV cm-2 s-1 sr-1 at 90% confidence level. This is the most restrictive experimental bound placed by any neutrino detector at these energies. Bounds to specific extra-terrestrial eutrino flux predictions are also presented. © 2004 Elsevier B.V. All rights reserved.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe