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The parities of eleven J=1 levels in 208Pb were determined by nuclear resonance fluorescence scattering of linearly polarized photons. A new 1+ level at Ex=5.846 MeV with Gamma 02 / Gamma =1.2±0.4 eV was found. This level can probably be identified with the theoretically predicted isoscalar 1+ state in 208Pb. All other bound dipole states below 7 MeV with Gamma 02 / Gamma >1.5 eV have negative parity. The 1- assignment to the 4.842-MeV level is of special significance because of previous conflicting results about its parity.
The 16O ( gamma ,p0) reaction has been studied with linearly polarized bremsstrahlung photons in and below the giant E1 resonance. The parity of the absorbed radiation was determined from the observed azimuthal asymmetry of the emitted protons. Combined with unpolarized measurements the polarized results determine the proton decay amplitudes of the M1 resonance at Ex=16.2 MeV in 16O. The shape of the unpolarized 16O ( gamma ,p3) angular distribution in the giant E1 resonance was derived from the measured analyzing power. NUCLEAR REACTIONS 16O( gamma ,p), E=15-25 MeV; measured analyzing power theta =90° linearly polarized bremsstrahlung; 16O dipole levels deduced pi ; 16.2 MeV 1+ resonance deduced p0 decay amplitudes; 16O GEDR deduced p3 angular distribution.
The ultrarelativistic quantum molecular dynamics model (UrQMD) is used to study global observables in central reactions of Au+Au at sqrt[s]=200A GeV at the Relativistic Heavy Ion Collider (RHIC). Strong stopping governed by massive particle production is predicted if secondary interactions are taken into account. The underlying string dynamics and the early hadronic decoupling implies only small transverse expansion rates. However, rescattering with mesons is found to act as a source of pressure leading to additional flow of baryons and kaons, while cooling down pions.
11 262 keV 1+ state in 20Ne
(1983)
The excitation energy of the lowest 1+, T=1 state in 20Ne, which is important for parity nonconservation studies, has been determined in a photon scattering experiment to be 11 262.3 ± 1.9 keV. Values for the gamma -ray branching of this level to the ground state and to the first 2+ level in 20Ne are 84 ± 5% and 16 ± 5%, respectively. NUCLEAR REACTIONS 20Ne( gamma , gamma ), E gamma <18 MeV, bremsstrahlung; measured E gamma , gamma branching. Ne natural targets.
Proton emission in relativistic nuclear collisions is examined for events of low and high multiplicity, corresponding to large and small impact parameters. Peripheral reactions exhibit distributions of protons in agreement with spectator-participant decay modes. Central collisions of equal-size nuclei are dominated by the formation and decay of a fireball system. Central collisions of light projectiles with heavy targets exhibit an enhancement in sideward emission which is predicted by recent hydrodynamical calculations.
Angular distributions for elastic and inelastic transitions in 20Ne + 16O scattering have been measured at E(20Ne)=50 MeV. For the 0+, 2+, and 4+ members of the 20Ne ground-state rotational band, the angular distributions exhibit pronounced backward peaking characteristic of an alpha -cluster exchange mechanism. The analysis of the ground-state transition in the first-order elastic transfer model yields no satisfactory fit although microscopic cluster form factors and full recoil corrections are employed. A coupled channels calculation for the 0+, 2+, and 4+ transitions reveals very strong coupling effects, indicating that the coherent superposition of first-order optical model and distorted-wave Born-approximation amplitudes may not be an adequate model for these reactions. NUCLEAR REACTIONS 16O(20Ne, 16O) and 16O(20Ne, 20Ne), elastic and inelastic transfer; E=50MeV; measured sigma (Ef , theta ); optical model + DWBA, and CCBA analyses.
The elastic alpha scattering to backward angles has been studied for 40,42,44,48Ca between 40.7 and 72.3 MeV. The cross sections for 40Ca are larger than those for the higher isotopes up to the highest energies. They show backward increases that disappear above 50 MeV. The enhancement factor for 40Ca over 42,44Ca varies smoothly with energy. 48Ca does also show a backward cross-section enhancement over 42,44Ca. alpha -cluster rotational bands in the 44Ti compound state, four-nucleon correlations in 40Ca, and the l-dependent optical model are discussed as approaches to understand the anomaly. The rotator model appears to agree qualitatively with the experimental data. It involves rotational bands extending at least up to J=16 in 44Ti.
We present simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) for the Arctic winter 2002/2003. We integrated a Lagrangian denitrification scheme into the three-dimensional version of CLaMS that calculates the growth and sedimentation of nitric acid trihydrate (NAT) particles along individual particle trajectories. From those, we derive the HNO3 downward flux resulting from different particle nucleation assumptions. The simulation results show a clear vertical redistribution of total inorganic nitrogen (NOy), with a maximum vortex average permanent NOy removal of over 5 ppb in late December between 500 and 550 K and a corresponding increase of NOy of over 2 ppb below about 450 K. The simulated vertical redistribution of NOy is compared with balloon observations by MkIV and in-situ observations from the high altitude aircraft Geophysica. Assuming a globally uniform NAT particle nucleation rate of 3.4·10−6 cm−3 h−1 in the model, the observed denitrification is well reproduced. In the investigated winter 2002/2003, the denitrification has only moderate impact (<=10%) on the simulated vortex average ozone loss of about 1.1 ppm near the 460 K level. At higher altitudes, above 600 K potential temperature, the simulations show significant ozone depletion through NOx-catalytic cycles due to the unusual early exposure of vortex air to sunlight.
Chlorine monoxide (ClO) plays a key role in stratospheric ozone loss processes at midlatitudes. We present two balloonborne in situ measurements of ClO conducted in northern hemisphere midlatitudes during the period of the maximum of total inorganic chlorine loading in the atmosphere. Both ClO measurements were conducted on board the TRIPLE balloon payload, launched in November 1996 in Le´on, Spain, and in May 1999 in Aire sur l’Adour, France. For both flights a ClO daylight and night time vertical profile could be derived over an altitude range of approximately 15–31 km. ClO mixing ratios are compared to model simulations performed with the photochemical box model version of the Chemical Lagrangian Model of the Stratosphere (CLaMS). Simulations along 24-h backward trajectories were performed to study the diurnal variation of ClO in the midlatitude lower stratosphere. Model simulations for the flight launched in Aire sur l’Adour 1999 show a good agreement with the ClO measurements. For the flight launched in Le´on 1996, a similar good agreement is found, except at around ~ 650 K potential temperature (~26km altitude). However, a tendency is found that for solar zenith angles greater than 86°–87° the simulated ClO mixing ratios substantially overestimate measured ClO by approximately a factor of 2.5 or more for both flights. Therefore we conclude that no indication can be deduced from the presented ClO measurements that substantial uncertainties exist in midlatitude chlorine chemistry of the stratosphere. An exception is the situation at solar zenith angles greater than 86°–87° where model simulations substantial overestimate ClO observations.
Back-angle enhancements of elastic alpha -scattering cross sections have been observed for nuclei at the ends of the 1p, 2s-1d, and f7 / 2 shells. Strong reduction of this enhancement occurs if excess neutrons enter the next open major shell. The results are discussed in terms of intermediate alpha structure.
Pion-production cross sections have been measured for the reaction 40Ar+40Ca--> pi ++X at a laboratory energy of 1.05 GeV/nucleon. A maximum in the pi + cross section occurs at mid-rapidity, which is anomalous relative to p+p and p+nucleus reactions and compared to many other heavy-ion reactions. Calculations based on cascade and thermal models fail to fit the data.
Inclusive energy spectra of protons, deuterons, and tritons were measured with a telescope of silicon and germanium detectors with a detection range for proton energies up to 200 MeV. Fifteen sets of data were taken using projectiles ranging from protons to 40Ar on targets from 27Al to 238U at bombarding energies from 240 MeV/nucleon to 2.1 GeV/nucleon. Particular attention was paid to the absolute normalization of the cross sections. For three previously reported reactions, He fragment cross sections have been corrected and are presented. To facilitate a comparison with theory the sum of nucleonic charges emitted as protons plus composite particles was estimated and is presented as a function of fragment energy per nucleon in the interval from 15 to 200 MeV/nucleon. For low-energy fragments at forward angles the protons account for only 25% of the nucleonic charges. The equal mass 40Ar plus Ca systems were examined in the center of mass. Here at 0.4 GeV/nucleon 40Ar plus Ca the proton spectra appear to be nearly isotropic in the center of mass over the region measured. Comparisons of some data with firestreak, cascade, and fluid dynamics models indicate a failure of the first and a fair agreement with the latter two. In addition, associated fast charged particle multiplicities (where the particles had energies larger than 25 MeV/nucleon) and azimuthal correlations were measured with an 80 counter array of plastic scintillators. It was found that the associated multiplicities were a smooth function of the total kinetic energy of the projectile. NUCLEAR REACTIONS U(20Ne,X), E / A=240 MeV/nucleon; U(40Ar,X), Ca(40Ar,X), U(20Ne,X), Au(20Ne,X), Ag(20Ne,X), Al(20Ne,X), U(4He,X), Al(4He,X), E / A=390 MeV/nucleon; U(40Ar,X), Ca(40Ar,X), U(20Ne,X), U(4He,X), U(p,X), E / A=1.04 GeV/nucleon; U(20Ne,X), E / A=2.1 GeV/nucleon; measured sigma (E, theta ), X=p,d,t.
Exclusive pi - and charged-particle production in collisions of Ar+KCl is studied at incident energies from 0.4 to 1.8 GeV/u. Complete disintegration of both nuclei is observed. The correlation between pi - and total charge multiplicity shows no islands of anomalous pion production. For constant numbers of proton participants the pi - multiplicity distributions are Poissons. For central collisions <n pi -> increases smoothly and to first order linearly with the c.m. energy. Disagreement with the firestreak model is found. Pacs numbers: 25.70.Hi, 24.10.Dp
Lambda 's produced in central collisions of 40Ar+KC1 at 1.8-GeV/u incident energy were detected in a streamer chamber by their charged-particle decay. For central collisions with impact parameters b<2.4 fm the Lambda production cross section is 7.6±2.2 mb. A calculation in which Lambda production occurs in the early stage of the collision qualitatively reproduces the results but underestimates the transverse momenta. An average Lambda polarization of -0.10±0.05 is observed. PACS numbers: 25.70 Bc
Pion production and charged-particle multiplicity selection in relativistic nuclear collisions
(1982)
Spectra of positive pions with energies of 15-95 MeV were measured for high energy proton, 4He, 20Ne, and 40Ar bombardments of targets of 27Al, 40Ca, 107,109Ag, 197Au, and 238U. A Si-Ge telescope was used to identify charged pions by dE / dx-E and, in addition, stopped pi + were tagged by the subsequent muon decay. In all, results for 14 target-projectile combinations are presented to study the dependence of pion emission patterns on the bombarding energy (from E / A=0.25 to 2.1 GeV) and on the target and the projectile masses. In addition, associated charged-particle multiplicities were measured in an 80-paddle array of plastic scintillators, and used to make impact parameter selections on the pion-inclusive data. NUCLEAR REACTIONS U(20Ne, pi +), E / A=250 MeV; U(40Ar, pi +), Ca(40Ar, pi +), U(20Ne, pi +), Au(20Ne, pi +), Ag(20Ne, pi +), Al(20Ne, pi +), U(4He, pi +), Al(4He, pi +). E / A=400 MeV; Ca(40Ar, pi +), U(20Ne, pi +), U(4He, pi +), U(p, pi +), E / A=1.05), GeV; U(20Ne, pi +), E / A=2.1 GeV; measured sigma (E, theta ), inclusive and selected on associated charged-particle multiplicity.
Energy spectra and angular distributions have been measured of 3He and 4He fragments emitted from Ag and U targets, bombarded with 2.7-GeV protons, and 1.05-GeV/nucleon alpha particles and 16O ions. All cross sections increase dramatically with projectile mass. No narrow peaks are found in the angular distributions or in the energy spectra.
Double-differential cross sections have been measured for high-energy p, d, t, 3He, and 4He particles emitted from uranium targets irradiated with 20Ne ions at energies of 250, 400, and 2100 MeV/nucleon and 4He ions at 400 MeV/nucleon. By using the shape and yield of the proton energy spectra, the shape and yield of the d, t, 3He, and 4He energy spectra can be deduced at all measured angles for all incident projectile energies by assuming that they are formed by a coalescence of cascade nucleons, using a model analogous to that of Butler and Pearson, and Schwarzschild and Zupancic-caron.
A simple model is proposed for the emission of nucleons with velocities intermediate between those of the target and projectile. In this model, the nucleons which are mutually swept out from the target and projectile form a hot quasiequilibrated fireball which decays as an ideal gas. The overall features of the proton-inclusive spectra from 250- and 400-MeV/nucleon 20Ne ions and 400-MeV/nucleon 4He ions interacting with uranium are fitted without any adjustable parameters.
The energy spectra of protons and light nuclei produced by the interaction of 4He and 20Ne projectiles with Al and U targets have been investigated at incident energies ranging from 0.25 to 2.1 GeV per nucleon. Single fragment inclusive spectra have been obtained at angles between 25° and 150°, in the energy range from 30 to 150 MeV/nucleon. The multiplicity of intermediate and high energy charged particles was determined in coincidence with the measured fragments. In a separate study, fragment spectra were obtained in the evaporation energy range from 12C and 20Ne bombardment of uranium. We observe structureless, exponentially decaying spectra throughout the range of studied fragment masses. There is evidence for two major classes of fragments; one with emission at intermediate temperature from a system moving slowly in the lab frame, and the other with high temperature emission from a system propagating at a velocity intermediate between target and projectile. The high energy proton spectra are fairly well reproduced by a nuclear fireball model based on simple geometrical, kinematical, and statistical assumptions. Light cluster emission is also discussed in the framework of statistical models. NUCLEAR REACTIONS U(20Ne,X), E=250 MeV/nucl.; U(20Ne,X), U(α,X) E=400 MeV/nucl.; U(20Ne,X), Al(20Ne,X), E=2.1 GeV/nucl.; measured σ(E,θ), X=p, d, t, 3He,4He. U(20Ne,X), U(α,X), E=400 MeV/nucl.; U(20Ne,X), E=2.1 GeV/nucl.; measured σ(E, θ), Li to O. U(20Ne,X), U(12C,X), E=2.1 GeV/nucl.; measured σ(E, 90°), 4He to B. Nuclear fireballs, coalescence, thermodynamics of light nuclei production.
Results are presented from a search for the decays D0 -> K min pi plus and D0 bar -> K plus pi min in a sample of 3.8x10^6 central Pb-Pb events collected with a beam energy of 158A GeV by NA49 at the CERN SPS. No signal is observed. An upper limit on D0 production is derived and compared to predictions from several models.
Particle production in central Pb+Pb collisions was studied with the NA49 large acceptance spectrometer at the CERN SPS at beam energies of 20, 30, 40, 80, and 158 GeV per nucleon. A change of the energy dependence is observed around 30A GeV for the yields of pions and strange particles as well as for the shapes of the transverse mass spectra. At present only a reaction scenario with onset of deconfinement is able to reproduce the measurements.
The transverse mass spectra of Omega hyperons and phi mesons measured recently by STAR Collaboration in Au+Au collisions at sqrt(s_NN) = 130 GeV are described within a hydrodynamic model of the quark gluon plasma expansion and hadronization. The flow parameters at the plasma hadronization extracted by fitting these data are used to predict the transverse mass spectra of J/psi and psi' mesons.
Efficient systems for the securities transaction industry : a framework for the European Union
(2003)
This paper provides a framework for the securities transaction industry in the EU to understand the functions performed, the institutions involved and the parameters concerned that shape market and ownership structure. Of particular interest are microeconomic incentives of the industry players that can be in contradiction to social welfare. We evaluate the three functions and the strategic parameters - the boundary decision, the communication standard employed and the governance implemented - along the lines of three efficiency concepts. By structuring the main factors that influence these concepts and by describing the underlying trade-offs among them, we provide insight into a highly complex industry. Applying our framework, the paper describes and analyzes three consistent systems for the securities transaction industry. We point out that one of the systems, denoted as 'contestable monopolies', demonstrates a superior overall efficiency while it might be the most sensitive in terms of configuration accuracy and thus difficult to achieve and sustain.
Despite a lot of re-structuring and many innovations in recent years, the securities transaction industry in the European Union is still a highly inefficient and inconsistently configured system for cross-border transactions. This paper analyzes the functions performed, the institutions involved and the parameters concerned that shape market and ownership structure in the industry. Of particular interest are microeconomic incentives of the main players that can be in contradiction to social welfare. We develop a framework and analyze three consistent systems for the securities transaction industry in the EU that offer superior efficiency than the current, inefficient arrangement. Some policy advice is given to select the 'best' system for the Single European Financial Market.
In recent years stock exchanges have been increasingly diversifying their operations into related business areas such as derivatives trading, post-trading services and software sales. This trend can be observed most notably among profit-oriented trading venues. While the pursuit for diversification is likely to be driven by the attractiveness of these investment opportunities, it is yet an open question whether certain integration activities are also efficient, both from a social welfare and from the exchanges' perspective. Academic contributions so far analyzed different business models primarily from the social welfare perspective, whereas there is only little literature considering their impact on the exchange itself. By employing a panel data set of 28 stock exchanges for the years 1999-2003 we seek to shed light on this topic by comparing the factor productivity of exchanges with different business models. Our findings suggest three conclusions: (1) Integration activity comes at the cost of increased operational complexity which in some cases outweigh the potential synergies between related activities and therefore leads to technical inefficiencies and lower productivity growth. (2) We find no evidence that vertical integration is more efficient and productive than other business models. This finding could contribute to the ongoing discussion about the merits of vertical integration from a social welfare perspective. (3) The existence of a strong in-house IT-competence seems to be beneficial to overcome.
Academic contributions on the demutualization of stock exchanges so far have been predominantly devoted to social welfare issues, whereas there is scarce empirical literature referring to the impact of a governance change on the exchange itself. While there is consensus that the case for demutualization is predominantly driven by the need to improve the exchange's competitiveness in a changing business environment, it remains unclear how different governance regimes actually affect stock exchange performance. Some authors propose that a public listing is the best suited governance arrangement to improve an exchange's competitiveness. By employing a panel data set of 28 stock exchanges for the years 1999-2003 we seek to shed light on this topic by comparing the efficiency and productivity of exchanges with differing governance arrangements. For this purpose we calculate in a first step individual efficiency and productivity values via DEA. In a second step we regress the derived values against variables that - amongst others - map the institutional arrangement of the exchanges in order to determine efficiency and productivity differences between (1) mutuals (2) demutualized but customer-owned exchanges and (3) publicly listed and thus at least partly outsider-owned exchanges. We find evidence that demutualized exchanges exhibit higher technical efficiency than mutuals. However, they perform relatively poor as far as productivity growth is concerned. Furthermore, we find no evidence that publicly listed exchanges possess higher efficiency and productivity values than demutualized exchanges with a customer-dominated structure. We conclude that the merits of outside ownership lie possibly in other areas such as solving conflicts of interest between too heterogeneous members.
Wir untersuchten über einen Zeitraum von 5 Jahren 40 Patienten, bei denen die Diagnose einer Achalasie nach etablierten Kriterien gesichert worden war hinsichtlich der Effektivität und der Nebenwirkungen einer pneumatischen Dilatation mit einem neuartigen "Low - Compliance" Ballonsystem. Alle Patienten wurden vor, 4 - 6 Wochen und abschließend im Mittel 28 ± 15 Monate nach der pneumatischen Dilatation untersucht. Die pneumatische Dilatation erfolgte entweder unter Verwendung eines 30 oder 35 mm Ballonsystemes, abhängig von vorher festgelegten Kriterien. Zusätzlich konnte bei 12 dieser Patienten, vor - und im Mittel 26 ± 15 Monate nach der pneumatischen Dilatation, eine ösophageale pH - Messung durchgeführt werden. Insgesamt wurden 52 Dilatationen mit einer durchschnittlichen Dilatationszeit von 4 Minuten durchgeführt. Ein initialer Erfolg nach einmaliger pneumatischer Dilatation konnte bei 35 Patienten (87,5%) erreicht werden. Die übrigen 5 Patienten sowie weitere 7 Patienten, bei denen eine Dysphagie erneut auftrat, wurden ein zweites Mal dilatiert. Die beiden Patienten, bei denen auch nach dieser zweiten Dilatation noch deutliche Symptome bestanden, wurden einer operativen Kardiomyotomie zugeführt (Operationsfrequenz = 5%). Die Effektivität der Dilatation wurde durch eine signifikante Verringerung der klinischen Symptomatik dokumentiert. So verringerte sich der Symptomen - Score (1-14 Punkte) von 9,9 ± 2,1 Punkte vor pneumatischer Dilatation, auf 4,9 ± 2,4 Punkte 4-6 Wochen nach pneumatischer Dilatation und auf 4,9 ± 2,4 Punkte bei der Abschlußuntersuchung (p< 0,01). Der Ruhedruck des unteren Ösophagussphinkters konnte durch die Dilatation von 28,3 ± 0,8 mmHg auf 16,4 ± 6,4 mmHg nach Dilatation und weiter auf 14,7 ± 5,5 mmHg bei der Abschlußuntersuchung, gesenkt werden (p< 0,01). Weder der radiologisch bestimmte Durchmesser des tubulären Ösophagus, noch die manometrisch fassbaren Kontraktionsamplituden im tubulären Ösophagus wurden durch die pneumatische Dilatation signifikant beeinflußt. Betrachtet man die Nebenwirkungen, so zeigte die Langzeit pH - Metrie eine deutliche Erhöhung der Anzahl, sowie der Dauer der gastroösophagealen Refluxepisoden, mit einem pH < 4 nach der pneumatischen Dilatation. Konträr zu diesen Ergebnissen klagte allerdings nur ein Patient über Sodbrennen. Bei einem weiteren Patienten konnte, obwohl dieser keine Beschwerden angab, endoskopisch eine Ösophagitis Grad I gesichert werden. Es wurde eine Perforation beobachtet, eine operative Versorgung des Patienten war jedoch nicht erforderlich. Diese Ergebnisse zeigen, daß die pneumatische Dilatation mit dem "Low - Compliance" System eine adäquate Behandlungsmethode der Achalasie darstellt, die sich jedoch hinsichtlich ihrer Kurz - und Langzeiteffektivität nicht wesentlich von den bisher verwendeten Systemen unterscheidet.
Die standardisierte Kopplung des sozialen Sicherungssystems an eine ‚Normalarbeitsbiographie‘ geriet in den letzten Jahren immer stärker in die Kritik. Einerseits, weil die darauf aufbauenden Leistungen auf Dauer nicht mehr aufrechterhaltbar scheinen, da die Finanzierung durch immer weniger Erwerbsarbeit und immer mehr Leistungsbezug, v.a. durch die steigende Zahl der RentnerInnen, zunehmend erschwert wird. Andererseits wurde bereits in den 80er Jahren verstärkt Kritik an der mangelnden Leistungsfähigkeit des Sicherungssystems bezüglich der Vermeidung von Armut geäußert. Das deutsche Sozialstaatsmodell gerät in die Gefahr, nicht ähnliche Wohlfahrtsniveaus zu sichern, sondern neue Konflikte zu schüren, und die Gesellschaft in Profiteure und Nonprofiteure der Marktwirtschaft zu spalten. Die Zeiten, in denen man die Möglichkeit einer Vollbeschäftigung in den westlichen Industrieländern für realistisch hielt, scheinen zu Ende zu sein. Es gelingt VertreterInnen einer Politik der Vollbeschäftigung offenbar nicht, erfolgversprechende Konzepte zu entwickeln, die die zunehmende ‚Rationalisierung‘ der Produktionsprozesse mit einer Politik der ‚Arbeit für Alle‘ in Einklang bringen könnten. So sieht es danach aus, als könnte das ‚Normalarbeitsverhältnis‘, das jahrzehntelang Ziel einer sozialstaatlichen Aufwertung der Lohnarbeit war und als Versöhnung der Klassen unter dem Kapital angesehen wurde, nicht mehr mehrheitsfähig sein. Die Risikovielfalt unterschiedlicher Lebenswege kann nicht mehr mit standardisierten Sicherungsmaßnahmen aufgefangen werden. Seit den siebziger Jahren (und verstärkt seit Mitte der 80er Jahre) gibt es breite Bevölkerungsschichten, die nicht über ein existenzsicherndes Einkommen verfügen und somit als „arm“ bezeichnet werden können. Etwa 10% der Bevölkerung in den meisten westlichen Industriestaaten verfügen nur über ein Einkommen, das unter 50% des Durchschnittsnettoeinkommens der Gesamtbevölkerung des jeweiligen Landes liegt. Bis zu 20% der Bevölkerung verfügen über ein Einkommen, das unter 60% des Durchschnittsnettoeinkommens liegt. 25 – 30% der Gesamtbevölkerung sind nach Schätzungen in der BRD zumindest kurzzeitig von Armut betroffen. Die neue Armut ist nicht nur etwa bei der steigenden Zahl von SozialhilfebezieherInnen beobachtbar, sondern auch bei der in einem festen Arbeitsverhältnis stehenden Bevölkerung. „Armut trotz Arbeit“ nennt man diesen verbreiteten Zustand der sogenannten „working poor“. Zur Zeit stehen in der Bundesrepublik ca. 40% der Armen in einem festen Arbeitsverhältnis. 4 Eine Reform des sozialen Sicherungssystems besonders hinsichtlich einer Minimalsicherung in allen Lebensbereichen wird unausweichlich werden. Hierzu gibt es verschiedene Grundsicherungsmodelle, die in der Arbeit vorgestellt werden sollen. Der belgische Wissenschaftler Philippe van Parijs beschäftigt sich seit Ende der 70er Jahre mit einem besonderen Grundeinkommensmodell, nämlich dem „unbedingten Grundeinkommen“ (unconditional basic income). Im Mittelpunkt dieses Modells steht die Rechtfertigung der Einführung eines Rechts auf ein Mindesteinkommen für alle, welches dadurch erreicht werden soll, daß alle BürgerInnen ein Einkommen vom Staat zu Verfügung gestellt bekommen, das ihnen unabhängig von Arbeitsfähigkeit, Bedürftigkeit oder Arbeitswilligkeit ausgezahlt wird. Van Parijs‘ Modell ist deshalb von besonderem Interesse, weil es eine reichhaltige Schnittstelle von Grundsicherungssystemen einerseits und Gerechtigkeitstheorien andererseits darstellt. Es eignet sich besonders als Ausgangspunkt für eine dauerhafte interdisziplinäre Arbeit zwischen Soziologie, Ökonomie und Philosophie. Ist dieses Modell eine praktikable Lösung, d.h. ist dieses Modell finanzierbar und auch gegenüber anderen Modellen attraktiv? Ist es auch unter anspruchsvollen Gerechtigkeitsaspekten normativ rechtfertigbar? Ist es also gerecht, effektiv in bezug auf das Armutsproblem und wirtschaftlich effizient? Mit diesen Fragen will sich diese Arbeit auseinandersetzen. Die Arbeit gliedert sich in vier Hauptteile. Im ersten Hauptteil (A) wird eingehend die Geschichte der Armutsentwicklung behandelt. Es wird untersucht, welche Rolle die Armut in unterschiedlichen Gesellschaftsformen und insbesondere im Rahmen der Entwicklung bis hin zur modernen Industriegesellschaft gespielt hat. Es soll geklärt werden, inwieweit verschiedene Erklärungsmodelle entwickelt wurden, und welche Modelle für welche Armutstypen aussagekräftig sind. Außerdem wird genauer auf die Verfeinerung der Ansätze innerhalb der Soziologie der Armut eingegangen, die nötig waren, um das unklare Bild einer amorphen, neuen Armut aufzuhellen. Gewonnen werden soll aus diesen Kapiteln eine möglichst umfangreiche und genaue Gegenstandsbestimmung sowie die Beantwortung der Frage, ob die neue Armut mit der Entwicklung moderner Industriestaaten systematisch verknüpft ist, oder ob unterschiedliche Armutstypen unvermittelt nebeneinanderstehende Randerscheinungen verschiedener sozialer Organisationsformen sind. Weiterhin könnten Argumente für konstruktive legitimierbare Ansätze der Armutsvermeidung im Gegensatz zu destruktiven oder schlecht legitimierbaren Ansätzen gefunden werden. 5 Im zweiten Teil (B) werden verschiedene Grundsicherungsmodelle vorgestellt. Sie werden auf ihre Finanzierbarkeit, ihre Zielgenauigkeit, und auf ihre Fähigkeiten, mit den in den vorigen Kapiteln aufgeworfenen Problemen umzugehen, geprüft. Der dritte Teil (C) behandelt die normative Rechtfertigung von Umverteilungsmaßnahmen und Grundsicherung. Es werden verschiedene Gerechtigkeitstheorien unter besonderer Berücksichtigung der gerechten Güterverteilung vorgestellt. Anhand verschiedener Autoren aus dem libertären, liberalen und analytisch-marxistischen Spektrum werden Ansprüche und Probleme der Gerechtigkeitsfragen verdeutlicht. Im weiteren Verlauf wird die Theorie von van Parijs genauer vorgestellt. Es wird versucht, anhand des vorliegenden Textmaterials alle populären normativen Einwände gegen van Parijs auszuräumen. Als Ergebnis soll ein eigenes gerechtes Grundsicherungsmodell vorgestellt werden, das sich an van Parijs‘ Theorie orientiert, aber auch Anforderungen anderer Gerechtigkeitskonzeptionen berücksichtigt. Dieses Modell wird Income-Outcome Gerechtigkeit genannt. Zum Schluß (Teil D) wird der Versuch unternommen, das Income-Outcome Modell mit den Grundsicherungsmodellen aus (B) zu verknüpfen und mit den gewonnenen Anforderungen aus (A) zu vergleichen. So sollte es gelingen, ein gerechtes und sozialpolitisch diskutierbares Grundsicherungsmodell für die Bundesrepublik Deutschland zu entwickeln. A Armut und Armutsforschung Dieser Teil beschäftigt sich mit der Entstehung und Wandlung des Armutsbegriffs, mit der modernen Definition und Messung von Armut und mit der Rolle der Armut in unterschiedlichen Gesellschaftsformen. Außerdem werden aktuelle Ansätze der und Debatten innerhalb der Armutsforschung vorgestellt. Zunächst soll die Entstehung und Verwendung des Armutsbegriffs im wissenschaftlichen Kontext grob umrissen werden. Danach folgt eine eingehende Beschäftigung mit der historischen Entwicklung des Armutsbegriffs und mit seiner Verwendung in verschiedenen Epochen von Urgesellschaften über das Mittelalter bis hin zur modernen Industriegesellschaft.
In Zeiten der Zunahme prekärer Arbeitsverhältnisse und wachsender Ungleichverteilung der Einkommen ist die Entkoppelung von Einkommen und Erwerbsarbeit aktueller denn je. Im Verlauf der Arbeit wird Schritt für Schritt aufgezeigt, wie mit einem garantierten Grundeinkommen eine Reform der sozialen Sicherungssysteme gelingen kann. Der Weg des garantierten Grundeinkommens zeigt sich als beste Lösung, wenn Armutsfreiheit, diskontinuierliche Arbeit, selbstbestimmte Beschäftigung, ein Mindesteinkommen als soziales Grundrecht und die Reform des Wohlfahrtsstaats gleichermaßen gefördert werden sollen. Dieses Buch ist besonders als Einstiegslektüre in die Themen Armutsforschung, soziale Grundsicherungssysteme und Gerechtigkeitstheorien geeignet.
This paper studies a setting in which a risk averse agent must be motivated to work on two tasks: he (1) evaluates a new project and, if adopted, (2) manages it. While a performance measure which is informative of an agent´s action is typically valuable because it can be used to improve the risk sharing of the contract, this is not necessarily the case in this two-task setting. I provide a sufficient condition under which a performance measure that is informative of the second task is worthless for contracting despite the agent being risk averse. This shows that information content is a necessary but not a sufficient condition for a performance measure to be valuable.
It is widely believed that the ideal board in corporations is composed almost entirely of independent (outside) directors. In contrast, this paper shows that some lack of board independence can be in the interest of shareholders. This follows because a lack of board independence serves as a substitute for commitment. Boards that are dependent on the incumbent CEO adopt a less aggressive CEO replacement rule than independent boards. While this behavior is inefficient ex post, it has positive ex ante incentive effects. The model suggests that independent boards (dependent boards) are most valuable to shareholders if the problem of providing appropriate incentives to the CEO is weak (severe).
Das Tetralemma des Rechts : zur Möglichkeit einer Selbstbeschränkung des Kommunikationssystems Recht
(2000)
Was tut das Recht wenn es nichts tut? In diese Frage hat Niklas Luhmann das Problem gekleidet, wie ein judicial self-restraint unter Geltung des Justizverweigerungsverbotes denkbar ist. Eine Beantwortung dieser Frage aus Sicht einer Systemtheorie, die das Recht als operativ geschlossenes Kommunikationssystem im Rahmen einer auf der Erkenntnistheorie des radikalen Konstruktivismus fußenden Theorie der Gesellschaft zu erfassen sucht (Recht als autopoietisches System), hat Luhmann zwar angerissen, aber nicht befriedigend zu Ende gedacht. Besonders interessant ist diese Frage vor dem Hintergrund der Diskussion um ein prozedurales Rechtsparadigma, welches angesichts der gegenwärtigen gesellschaftlichen Umbrüche das überkommene materiale Paradigma ablösen soll (Prozeduralisierung des Rechts). Es erscheint daher reizvoll, auf der Suche nach Antworten einen Beitrag sowohl zur Systemtheorie des Rechts als auch zu einer Theorie des prozeduralen Rechts zu leisten.
Reflexive transnational law : the privatisation of civil law and the civilisation of private law
(2002)
The author examines the emergence of a transnational private law in alternative dispute resolution bodies and private norm formulating agencies from a reflexive law perspective. After introducing the concept of reflexive law he applies the idea of law as a communicative system to the ongoing debate on the existence of a New Law Merchant or lex mercatoria. He then discusses some features of international commercial arbitration (e.g. the lack of transparency) which hinder self-reference (autopoiesis) and thus the production of legal certainty in lex mercatoria as an autonomous legal system. He then contrasts these findings with the Domain Name Dispute Resolution System, which as opposed to Lex Mercatoria was rationally planned and highly formally organised by WIPO and ICANN, and which is allowing for self-reference and thus is designed as an autopoietic legal system, albeit with a very limited scope, i.e. the interference of abusive domain name registrations with trademarks (cybersquatting). From the comparison of both examples the author derives some preliminary ideas regarding a theory of reflexive transnational law, suggesting that the established general trend of privatisation of civil law need to be accompanied by a civilisation of private law, i.e. the constitutionalization of transnational private regimes by embedding them into a procedural constitution of freedom.
Wider participation in stockholding is often presumed to reduce wealth inequality. We measure and decompose changes in US wealth inequality between 1989 and 2001, a period of considerable spread of equity culture. Inequality in equity wealth is found to be important for net wealth inequality, despite equity's limited share. Our findings show that reduced wealth inequality is not a necessary outcome of the spread of equity culture. We estimate contributions of stockholder characteristics to levels and inequality in equity holdings, and we distinguish changes in configuration of the stockholder pool from changes in the influence of given characteristics. Our estimates imply that both the 1989 and the 2001 stockholder pools would have produced higher equity holdings in 1998 than were actually observed for 1998 stockholders. This arises from differences both in optimal holdings and in financial attitudes and practices, suggesting a dilution effect of the boom followed by a cleansing effect of the downturn. Cumulative gains and losses in stockholding are shown to be significantly influenced by length of household investment horizon and portfolio breadth but, controlling for those, use of professional advice is either insignificant or counterproductive. JEL Classification: E21, G11