17 research outputs found
Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR
Substantial experimental and theoretical efforts worldwide are devoted to
explore the phase diagram of strongly interacting matter. At LHC and top RHIC
energies, QCD matter is studied at very high temperatures and nearly vanishing
net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was
created at experiments at RHIC and LHC. The transition from the QGP back to the
hadron gas is found to be a smooth cross over. For larger net-baryon densities
and lower temperatures, it is expected that the QCD phase diagram exhibits a
rich structure, such as a first-order phase transition between hadronic and
partonic matter which terminates in a critical point, or exotic phases like
quarkyonic matter. The discovery of these landmarks would be a breakthrough in
our understanding of the strong interaction and is therefore in the focus of
various high-energy heavy-ion research programs. The Compressed Baryonic Matter
(CBM) experiment at FAIR will play a unique role in the exploration of the QCD
phase diagram in the region of high net-baryon densities, because it is
designed to run at unprecedented interaction rates. High-rate operation is the
key prerequisite for high-precision measurements of multi-differential
observables and of rare diagnostic probes which are sensitive to the dense
phase of the nuclear fireball. The goal of the CBM experiment at SIS100
(sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD
matter: the phase structure at large baryon-chemical potentials (mu_B > 500
MeV), effects of chiral symmetry, and the equation-of-state at high density as
it is expected to occur in the core of neutron stars. In this article, we
review the motivation for and the physics programme of CBM, including
activities before the start of data taking in 2022, in the context of the
worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal
Entwicklung und Validierung eines laenderuebergreifenden Handlungsrasters bei der Altlastensanierung auf der Grundlage abgeschlossener Sanierungsmassnahmen. Handlungsraster Altlastensanierung. Bd. 2
Based on an analysis of completed projects for the cleanup of contaminated sites, working aids in the form of flow schemes have been developed for the work stages investigation, planning, performance of remedial action, aftercare and long-term monitoring. Consolidating the experience gained so far in Germany in cleanup projects, they set out general procedures for decision-making and action in the course of contaminated sites treatment. The flow schemes are uniform in structure and each include an introduction to the respective area concerned. In cases in which the technical scope of the work and the detail of the task so demand, sub-schemes have been allocated to individual stages. These provide a sufficiently sound technical basis for the respective tasks at hand, reflecting in condensed form the available experience. The flow schemes developed for remediation planning and aftercare relate to relatively new fields of contaminated sites remediation and hence document the current status of the discussion or present practices in these fields. The flow schemes presented are to serve as guidance for those responsible for remediation, for planners as well as for the competent authorities. They also contain useful suggestions and hints for affected parties, remediation firms and local authorities. Numerous cross-references permit users to explore relevant issues in greater depth at a given stage while simultaneously taking on checking and memory functions. An aspect to be highlighted is the numerous links with urban land use planning. (orig.)SIGLEAvailable from TIB Hannover: RN 8422(1998,11,2) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Bonn (Germany)DEGerman
Vorbereitung, Koordinierung, Durchfuehrung und Auswertung der im Rahmen der deutsch-amerikanischen Zusammenarbeit geplanten zusaetzlichen Untersuchungen an ausgewaehlten Altlastensanierungsfaellen. Bd. 1 Ablauf und Ergebnisse der BMBF - U.S. EPA Zusammenarbeit. Schlussbericht
In April 1990 the Federal German Ministry of Eudcation, Science, Research and Technology (BMBF; formerly named Federal German Ministry of Research and Technology, BMFT) and the United States Environmental Protection Agency (U.S. EPA) agreed upon a Bilateral Agreement on Contaminated Sites. The first work-phase, comprised joint demonstrations of six remedial technologies in both, the United States and Germany. Testing and Monitoring was done according to German and U.S. standards and procedures. Demonstration results are documented and evaluated in the volumes 2 and 3 of the final report on this R+D-project. For the German partner of this international cooperation, an analysis of U.S. EPA's quality management (QM) approach in environmental data collection was of focal interest. This analysis and the conclusions regarding an improvement of QM in contaminated sites handling in Germany is documented in volume 1 of the report. (orig.)SIGLEAvailable from TIB Hannover: F98B254+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman
Entwicklung und Pruefung von Ueberwachungsstandards fuer Altlasten im Rahmen der Deutsch/Amerikanischen Zusammenarbeit auf dem Gebiet der Altlastensanierung. T. 1: Phase II der Bilateralen Kooperation des BMBF mit der U.S. EPA. T. 2: Leitfaden fuer die Tests von Dekontaminationsanlagen - Empfehlungen fuer einen Deutschen Technikstandard-Altlasten-Dekontamination - DETAD. T. 3: Konzept fuer den Deutschen Monitoringstandard-Altlasten-Sanierung (DEMAS) -Verfahrensanweisung zur Planung und Durchfuehrung der Ueberwachung sanierter Flaechen Schlussbericht
Published in 3 volumesAvailable from TIB Hannover: F01B1477: F01B1478: F01B1479 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung, Berlin (Germany); Umweltbundesamt, Berlin (Germany). Projekttraegerschaft Abfallwirtschaft und AltlastensanierungDEGerman
Abwassertechnische Aspekte bei der Schadstoffreduzierung aus Abgasen Schlussbericht
With 133 refs., 48 tabs., 45 figs.Copy held by UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
Vorbereitung, Koordinierung, Durchfuehrung und Auswertung der im Rahmen der deutsch-amerikanischen Zusammenarbeit geplanten zusaetzlichen Untersuchungen an ausgewaehlten Altlastensanierungsfaellen. Bd. 2 In der Bundesrepublik Deutschland durchgefuehrte Technikdemonstrationen. Schlussbericht
In April 1990 the Federal German Ministry of Education, Science, Research and Technology (BMBF; formerly named Federal German Ministry of Research and Technology, BMFT) and the United States Environmental Protection Agency (U.S. EPA) agreed upon a Bilateral Agreement on Contaminated Sites. The first work-phase, comprised joint demonstrations of six remedial technologies in both, the United States and Germany. Testing and Monitoring was done according to German and U.S. standards and procedures. Demonstration results are documented and evaluated in the volumes 2 and 3 of the final report on this R+D-project. For the German partner of this international co-operation, an analysis of U.S. EPA's quality management (QM) approach in environmental data collection was of focal interest. This analysis and the conclusions regarding an improvement of QM in contaminted sites handling in Germany is documented in volume 1 of the report. (orig.)SIGLEAvailable from TIB Hannover: F98B255+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman
Orthogonal frequency division multiplexing (OFDM) in photonic communications
OFDM has emerged as a promising modulation technique in long-haul and access optical networks because of a number of advantages: Scalable spectrum partitioning, good spectral efficiency, dispersion tolerance, and a natural suitability for software-defined transmission. However, there are also issues inherent in OFDM: High peak-to-average power ratio making the system more susceptible to nonlinearity, sensitivity to frequency offset and phase noise, and the required computational complexity. With the advent of powerful digital signal processors and by exploiting all-optical signal processing, some of these obstacles can be overcome
Analyse durchgefuehrter Altlastensanierungen im Hinblick auf Sanierungserfolge (Monitoring sanierter Altlasten)
In the project strategies were elaborated, through evaluation of practical cases, for a standardised decision-making process applicabel to all Laender with regard to the sanitation of hazordous waste sites in the task areas of remedial investigations, project planning, implementation of remedial measures and monitoring of success. 25 remedial measures conducted in 8 Laender were investigated in this respect. It became clear that the experience gained and the approach chosen in these cases of remedial action were only generalisable or transferable to a limited degree. The analysis of the particular circumstances and of the feasibility of a remedial measure has proved itself as an essential precondition for the application of ecologically and economically appropriate procedures and techniques. This preliminary step to a sanitation measure, the remedial investigation, permits a flexible and dynamic approach to the optimal harmonisation of remedial action with the location-specific circumstances of a hazardous waste site. (orig.)Available from TIB Hannover: RN 8422(1996,67) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Bonn (Germany)DEGerman
Arbeitshilfe: Anforderungen an eine Sanierungsuntersuchung unter Beruecksichtigung von Nutzen-Kosten-Aspekten
With CD-ROMSIGLEAvailable from TIB Hannover: RR 8521(11) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Colorless FDMA-PON with flexible bandwidth allocation and colorless, low-speed ONUs [invited]
We demonstrate a remotely seeded flexible passive optical network (PON) with multiple low-speed subscribers but only a single optical line terminal transceiver operating at a data rate of 31.25 Gbits/s. The scheme is based on a colorless frequency division multiplexing (FDM)-PON with centralized wavelength control. Multiplexing and demultiplexing in the optical network unit (ONU) is performed in the electronic domain and relies either on FDM with Nyquist sinc-pulse shaping or on orthogonal frequency division multiplexing (OFDM). This way the ONU can perform processing at low speed in the baseband. Further, the ONU is colorless by means of a remote seed for upstream transmission and a remote local oscillator for heterodyne reception, all of which helps in keeping maintenance and costs for an ONU potentially low and will simplify wavelength allocation in a future software defined network architecture. To extend the reach, semiconductor optical amplifiers are used for optical amplification in the downstream and upstream.Peer reviewe