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AbstractAbstract
[en] The SAPHIR detector measures photon induced reactions with many particles in the final state. Thus a detailed investigation of those processes at photon energies between 0.4 and 3.3 GeV is possible. The interpretation of the distribution of the sample of events, which SAPHIR is able to reconstruct, has to be done after a correction of influences induced by the detector acceptance. In this work a model independent method of correcting and analysing the data is discussed. The implementation of the basic tools of this analysis is described and first tests with simulated and real events are performed. SAPHIR uses a time-of-flight system for the identification of particles. This work describes the structure of a program library, which supports an easy way of decoding the digitizations of this system (including calibration of the hardware) and obtaining the flight time for a particle in a event. The necessary step for calibrating the system are outlined, too. (orig.)
Original Title
Entwicklung einer Modell-unabhaengigen Auswertung von Photon-Deuteron-Reaktionen fuer den SAPHIR-Detektor
Primary Subject
Secondary Subject
Source
20 Oct 1993; 80 p; ISSN 0172-8741; 
; Diss.
; Diss.
Record Type
Report
Literature Type
Thesis/Dissertation
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Country of publication
BONN SYNCHROTRON, BREAKUP REACTIONS, CALIBRATION, COMPUTER CODES, COUNTING TECHNIQUES, DATA PROCESSING, DEUTERIUM TARGET, EFFECTIVE MASS, GEV RANGE 01-10, MASS SPECTRA, MEV RANGE 100-1000, PARTICLE IDENTIFICATION, PHOTON-NEUTRON INTERACTIONS, PHOTON-PROTON INTERACTIONS, PHOTONUCLEAR REACTIONS, PHOTOPRODUCTION, PION DETECTION, PIONS MINUS, PIONS NEUTRAL, PROTON DETECTION, PROTONS, QUASI-FREE REACTIONS, RELATIVISTIC RANGE, SCATTERPLOTS, TIME-OF-FLIGHT METHOD
ACCELERATORS, BARYONS, BASIC INTERACTIONS, BOSONS, CATIONS, CHARGED PARTICLE DETECTION, CHARGED PARTICLES, CYCLIC ACCELERATORS, DETECTION, DIAGRAMS, DIRECT REACTIONS, ELECTROMAGNETIC INTERACTIONS, ELEMENTARY PARTICLES, ENERGY RANGE, FERMIONS, GEV RANGE, HADRONS, HYDROGEN IONS, HYDROGEN IONS 1 PLUS, INFORMATION, INTERACTIONS, IONS, MASS, MESONS, MEV RANGE, NUCLEAR REACTIONS, NUCLEONS, PARTICLE INTERACTIONS, PARTICLE PRODUCTION, PHOTON-BARYON INTERACTIONS, PHOTON-HADRON INTERACTIONS, PHOTON-NUCLEON INTERACTIONS, PIONS, PSEUDOSCALAR MESONS, RADIATION DETECTION, SPECTRA, SYNCHROTRONS, TARGETS
Publication YearPublication Year
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AbstractAbstract
No abstract available
Primary Subject
Source
Aug 1973; 132 p; diagrams; 107 refs.; Thesis (Ph.D.).
Record Type
Report
Literature Type
Thesis/Dissertation
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Country of publication
ANGULAR DISTRIBUTION, ARSENIC 75, CADMIUM 112, ENERGY LEVELS, ENERGY SPECTRA, ENERGY-LEVEL TRANSITIONS, GALLIUM 69, GAMMA RADIATION, GIANT RESONANCE, HEAVY NUCLEI, INELASTIC SCATTERING, INTERMEDIATE MASS NUCLEI, KEV RANGE 100-1000, LEVEL WIDTHS, MEV RANGE 01-10, MOLYBDENUM 100, NICKEL 62, NUCLEAR PROPERTIES, NUCLEAR REACTIONS, NUCLEAR STRUCTURE, PHOTONS, POLARIZATION, PORTER-THOMAS DISTRIBUTION, STRENGTH FUNCTIONS, THALLIUM 203, THALLIUM 205, TIN 120, ZINC 66
ARSENIC ISOTOPES, CADMIUM ISOTOPES, DISTRIBUTION, ELECTROMAGNETIC RADIATION, ELEMENTARY PARTICLES, ENERGY RANGE, EVEN-EVEN NUCLEI, FUNCTIONS, GALLIUM ISOTOPES, ISOMERIC TRANSITION ISOTOPES, ISOTOPES, KEV RANGE, MEV RANGE, MOLYBDENUM ISOTOPES, NICKEL ISOTOPES, NUCLEI, ODD-EVEN NUCLEI, RADIATIONS, RADIOISOTOPES, RESONANCE, SCATTERING, SECONDS LIVING RADIOISOTOPES, SPECTRA, STABLE ISOTOPES, THALLIUM ISOTOPES, TIN ISOTOPES, ZINC ISOTOPES
Publication YearPublication Year
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AbstractAbstract
[en] Divergence and size of stored ion beams can be reduced superimposing on them an intense, monoenergetic electron beam with little transverse motion ('electron cooling'). The present work first considers the theoretical foundations of the method and then describes the planning and construction of an electron beam device for cooling antiprotons with MeV energies in the storage ring LEAR and CERN. With respect to the quantitative description of the method, the microscopic processes during the damping of the ion motion, the effect of the damping on an ion in a storage ring, and the properties of the intense, magnetically guided electron beam are discussed. Special attention is paid to the improvement of ion beam cooling due to the magnetic field guiding the electron beam. The electron beam device, operated in ultra-high vacuum, and the experience gained during its construction are described; experiments performed during the test period are presented. The work further develops a numerical simulation of electron cooling on the basis of the theory discussed. Given realistic external parameters, the simulation yields cooling times and equilibrium states of the ion beam during electron cooling in a storage ring. Finally, non-destructive methods for measuring the velocity distribution in the electron beam are described, which may prove helpful for optimizing the beam cooling. (orig.)
[de]
Divergenz und Strahlgroesse von gespeicherten Ionenstrahlen lassen sich verringern, indem man ihnen einen intensiven, monoenergetischen Elektronenstrahl mit geringer Transversalbewegung ueberlagert ('Elektronenkuehlung'). Die vorliegende Arbeit behandelt zunaechst die theoretischen Grundlagen der Methode und beschreibt anschliessend Planung und Aufbau einer Elektronenstrahlapparatur zur Kuehlung von Antiprotonen mit MeV-Energien im Speicherring LEAR am CERN. Im Hinblick auf die quantitative Beschreibung des Verfahrens werden die mikroskopischen Vorgaenge bei der Daempfung der Ionenbewegung, die Auswirkung der Daempfung auf die Ionen in einem Speicherring und die Eigenschaften des verwendeten intensiven, magnetisch gefuehrten Elektronenstrahls diskutiert. Besondere Aufmerksamkeit wird den vorteilhaften Auswirkungen des magnetischen Fuehrungsfelds fuer den Elektronenstrahl auf die Kuehlung des Ionenstrahls geschenkt. Die im Ultrahochvakuum betriebene Elektronenstrahlapparatur und die bei ihrem Aufbau gewonnenen Erfahrungen werden beschrieben; beim Testbetrieb durchgefuehrte Experimente werden dargestellt. Die Arbeit behandelt weiterhin die numerische Simulation der Elektronenkuehlung auf der Grundlage der diskutierten Theorie. Durch die Simulation werden Kuehlzeiten und Gleichgewichtszustaende des Ionenstrahls bei Elektronenkuehlung in einem Speicherring nach Vorgabe realistischer aeusserer Parameter berechnet. Abschliessend werden zerstoerungsfreie Methoden zur Ausmessung der Geschwindigkeitsverteilung im Elektronenstrahl beschrieben, die bei der Optimierung der Strahlkuehlung behilflich sein koennen. (orig.)Original Title
Elektronenkuehlung fuer nierderenergetische Antiprotonen
Primary Subject
Source
Feb 1986; 165 p; Diss.
Record Type
Report
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Thesis/Dissertation
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AbstractAbstract
[en] The SAPHIR detector at the new ELSA-Ring in Bonn probes reactions of photons with light nuclei, such as Hydrogen or Deuterium. It is designed for multi purpose usage and so it is possible to answer various questions in this field of physics. SAPHIR will able to measure reactions with many particles (charged or uncharged) in the final state. It also uses a tagging system so that the energy of the photon in the initial state is known. For an effective and fast offline analysis the great amount of data coming from the electronics must be reduced to a minimum. For this purpose SAPHIR uses a multi stage trigger system. At first a fast coincidence and veto suppresses the e+e- pairs and the second stage resets the detector, if the number of charged and uncharged particles in the final state doesn't match a trigger condition defined by the user. This decision has to be made in a few microseconds to reduce deadtime effects due to this trigger. To match these requirements the second trigger level is built from special electronics which widely uses the Memory Lookup Concept and had to be developed. Setup and functions of these electronic modules are described in this report. The software tools for handling the trigger system are also outlined. (orig.)
[de]
In dieser Diplomarbeit wurde die zweite Triggerstufe von SAPHIR aufgebaut und ausfuehrlich getestet. Dabei wurden die gesamte Elektronik fertiggestellt und ueberprueft. Dies geschah u.a. durch rechnergestuetzte Untersuchungen, die auch nach Fertigstellung der zweiten Triggerstufe eine weitgehende Kontrolle der Funktion der Elektronik erlauben. Zum funktionsfaehigen Ausbau gehoerte auch der Bau und die Programmierung des Clusterfinders und die Konstruktion des Clustersenders, der die Verbindung zwischen Auslesesystem und 'EMC-Einheit' herstellt. Zum Betrieb der zweiten Triggerstufe mussten Programme und Programmteile geschrieben werden, die der Online-Software des SAPHIR-Experiments erlauben, den Trigger einzustellen und zu kontrollieren. Ein menuegesteuertes, unabhaengiges Programm im Mikrocomputer VIP ermoeglicht die Kontrolle ueber alle Register, die in der Elektronik existieren. Da diese komplexe Struktur dem 'normalen Benutzer' verborgen bleiben soll, war es noetig eine einfache 'Programmierumgebung' und die dazu benoetigte Software zu schaffen. Fuer die Verwendung des Triggers durch den Exprimentator wurde eine symbolische Programmiersprache definiert und ein Uebersetzungsprogramm auf den VAX-Rechner des Instituts implementiert. Dieses erlaubt eine einfache Festlegung der Triggerbedingung fuer bestimmte physikalische Fragestellungen. Mit Hilfe dieser erzeugten Datei kann das SAPHIR-Online die zweite Triggerstufe 'programmieren'. Damit ist der SAPHIR-Physik-Trigger fertiggestellt und durch den Benutzer einstellbar und verwendbar. (orig.)Original Title
Die zweite Triggerstufe des SAPHIR-Detektors
Source
Jul 1990; 61 p; Available from Bonn Univ. (Germany, F.R.). Physikalisches Inst; Diploma Thesis.
Record Type
Report
Literature Type
Thesis/Dissertation
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Country of publication
ANTICOINCIDENCE, BACKGROUND RADIATION, BONN SYNCHROTRON, CHARGED PARTICLE DETECTION, COINCIDENCE CIRCUITS, DEAD TIME, DEUTERIUM TARGET, DRIFT CHAMBERS, MEV RANGE 100-1000, MULTIPLICITY, MULTIWIRE PROPORTIONAL CHAMBER, PARTICLE DISCRIMINATION, PHOTON-PROTON INTERACTIONS, PHOTONUCLEAR REACTIONS, TRIGGER CIRCUITS
ACCELERATORS, BASIC INTERACTIONS, CYCLIC ACCELERATORS, DETECTION, ELECTROMAGNETIC INTERACTIONS, ELECTRONIC CIRCUITS, ENERGY RANGE, INTERACTIONS, MEASURING INSTRUMENTS, MEV RANGE, NUCLEAR REACTIONS, PARTICLE IDENTIFICATION, PARTICLE INTERACTIONS, PHOTON-BARYON INTERACTIONS, PHOTON-HADRON INTERACTIONS, PHOTON-NUCLEON INTERACTIONS, PROPORTIONAL COUNTERS, PULSE CIRCUITS, RADIATION DETECTION, RADIATION DETECTORS, RADIATIONS, SYNCHROTRONS, TARGETS, TIMING PROPERTIES
Publication YearPublication Year
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Cheifetz, E.; Wolf, A.
Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Nuclear Physics
Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Nuclear Physics
AbstractAbstract
[en] Spontaneous fission of 252Cf produces very neutron-rich isotopes falling mainly in three interesting regions of the periodic table: a) the A=100-120, Z=38-46 region for which there is evidence of large deformations; b) the isotopes around the double magic 132Sn where simple configurations coupled to the closed shells Z=50, N=82 prevail; c) the region with A=140-150, Z=54-60, where there is a smooth transition from spherical to deformed nuclei. Many isomeric γ-rays with half-lives between 10-3000 nsec were found to be emitted by fragments in regions (a) and (b). In this work γ-factors of isomeric states in fission fragments were measured. Two experiments were carried out. In the first, angular distributions (with respect to the fission axis) of known isomeric γ-rays emitted by stopped fragment were found to be anisotropic, thus showing alignment of the angular momentum. In the second experiment, this alignment was used in a time-different perturbed angular correlation measurement from which g-factors were directly obtained. (B.G.)
Primary Subject
Source
1976; 19 p
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Report
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AbstractAbstract
No abstract available
Primary Subject
Source
Garg, J.B. (ed.); p. 257-262; 1972; Plenum Publishing Corp; New York; International conference on statistical properties of nuclei; Albany, N. Y; 23 Aug 1971
Record Type
Book
Literature Type
Conference
Country of publication
BEAMS, CADMIUM ISOTOPES, ELEMENTARY PARTICLES, ENERGY-LEVEL TRANSITIONS, EVEN-EVEN NUCLEI, INELASTIC SCATTERING, INTERMEDIATE MASS NUCLEI, ISOMERIC TRANSITION ISOTOPES, ISOTOPES, NICKEL ISOTOPES, NUCLEI, ODD-EVEN NUCLEI, RADIOISOTOPES, SAMARIUM ISOTOPES, SCATTERING, SECONDS LIVING RADIOISOTOPES, STABLE ISOTOPES, TIN ISOTOPES
Publication YearPublication Year
Reference NumberReference Number
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AbstractAbstract
No abstract available
Primary Subject
Source
Israel Atomic Energy Commission, Tel Aviv; p. 112; Jun 1986; p. 112
Record Type
Report
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Country of publication
Publication YearPublication Year
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Wustmann, B.; Wolf, A.
Forschungszentrum Rossendorf. Institute of Nuclear and Hadron Physics. Annual report 2000
Forschungszentrum Rossendorf. Institute of Nuclear and Hadron Physics. Annual report 2000
AbstractAbstract
No abstract available
Primary Subject
Source
Doenau, F.; Enghardt, W.; Grosse, E.; Kaempfer, B.; Schlett, M.; Schneidereit, C. (eds.); Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany). Inst. fuer Kern- und Hadronenphysik; 159 p; ISSN 1437-322X; ; Apr 2001; p. 34-35
; Apr 2001; p. 34-35
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Report
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Related RecordRelated Record
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AbstractAbstract
[en] Apparatus for use during polishing and sectioning operations of a ribbon sample is described. The sample holder includes a cylinder having an axially extending sample cavity terminated in a first funnel-shaped opening and a second slot-like opening. A spring-loaded pressure plunger is located adjacent the second opening of the sample cavity for frictional engagement of the sample prior to introduction of a molding medium in the sample cavity. A heat softenable molding medium is inserted in the funnel-shaped opening, to surround the sample. After polishing, the heater is energized to allow draining of the molding medium from the sample cavity. During manual polishing, the second end of the sample holder is inserted in a support ring which provides mechanical support as well as alignment of the sample holder during polishing. A gauge block for measuring the protrusion of a sample beyond the second wall of the holder is also disclosed
Primary Subject
Secondary Subject
Source
7 Aug 1984; v p; US PATENT DOCUMENT 4,463,927/A/; U.S. Commissioner of Patents, Washington, D.C. 20231, USA, $.50; PAT-APPL-469350.
Record Type
Patent
Country of publication
Publication YearPublication Year
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Wolf, A.; Cheifets, E.
Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Nuclear Physics
Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Nuclear Physics
AbstractAbstract
[en] Angular distributions of specific γ-rays emitted in the de-excitation of prompt fission products of 252Cf were measured with respect to the fission direction. A total of 42 angular distributions were measured, 23 of which were of transitions in even-even fragments. The strong anisotropy (A2=0.4-0.6) measured for 2+→0+, 4+→2+, and 6+→4+ transitions in 138,140Xe and 142,144Ba provides direct evidence that the angular momentum of the primary fragments is completely aligned perpendicular to the fission axis. Most of the results are consistent with the results of a statistical calculation. The anisotropies measured for some transitions in even-odd fragments were combined with information of other authors in an attempt to determine spins of low-lying levels in these fragments. Finally, it is shown that about 60% of the anisotropy of the gross unresolved γ-ray spectrum, measured extensively by other authors, is due to transitions in the ground state band of even-even fragments. (author)
Primary Subject
Source
1976; 32 p; 7 figs.
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Report
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