Yes

Moderne Lasereinrichtungen stellen hochintensives Licht mit sehr kurzer zeitlicher Struktur zur Verfügung. Damit bringen diese Einrichtungen die Phänomene in die Laboratorien, welche normalerweise nur in der Nähe von stark strahlenden Sternen im Weltall zu finden sind. Bezüglich der Streuprozesse von Teilchen innerhalb dieser extremen Lichtquellen gibt es eine Vielzahl an theoretischen Untersuchungen. Vorwiegend geschehen diese unter der Verwendung der Starkfeld-Quantenelektrodynamik, einer Theorie zur quanten- theoretischen Beschreibung von elektromagnetischen Wechselwirkungen innerhalb eines kohärenten hochintensiven Feldes, welches als semi-klassisches Hintergrundfeld beschrieben wird. Zum Beispiel zeigte die theoretische Behandlung des Compton-Prozesses (die inelastis- che Elektron-Photon-Streuung) oder des Breit-Wheeler-Prozesses (der Paarproduktion in der Kollision von zwei Photonen) innerhalb der Starkfeld-Quantenelektrodynamik eine große Menge an neuen nicht-linearen Effekten und Phänomen, welche stellenweise in zukun- ftsweisenden Experimenten nachgewiesen werden konnten. Von großem Interesse und auch zentrales Untersuchungsobjekt der vorliegenden Arbeit ist ebenso der Trident-Prozess: ein Prozess zweiter Ordnung in der (Starkfeld-) Quan- tenelektrodynamik, bei dem ein Elektron-Positron-Paar innerhalb der Kollision eines Photonstrahls (z.B. erzeugt von einem Laser) und eines gegenläufigen Elektronenstrahls entsteht. Allerdings ist der Trident-Prozess im Zusammenhang mit hochintensiven Feldern nicht ausschließlich das Produkt seiner Teile, den erwähnten Compton- und Breit-Wheeler- Prozessen, vielmehr erzeugt das Vorhandensein des intermediären Photons durch seine virtuellen und reellen Beträge überaus komplizierte Strukturen. In den letzten Jahren gab es daher eine große Menge an theoretischen Beiträgen zur nicht-linearen Behandlung des Trident-Prozesses bezüglich eines weiten Bereichs an Eigenschaften der verwendeten Lichtquelle. Jedoch ist der nicht-lineare Trident-Prozess wegen seiner anspruchsvollen mathematischen Natur bisher nicht als völlig verstanden anzusehen. In der vorliegen- den Arbeit liegt der Fokus auf der Abhängigkeit des Trident-Prozesses von den kurzen zeitlichen Strukturen der verwendeten Lichtquellen bei hohen Energien. Grob gesprochen bedeutet dies, dass die kurz gepulsten Strukturen der modernen Lichtquellen zu breiten Spektren der Photonstrahlen führen, welche sich dann auch in den betrachteten Prozessen widerspiegeln. Demfolgend wird in der vorliegenden Arbeit eine neue Approximation an die Starkfeld-Quantenelektrodynamik erarbeitet, welche in der Lage ist, die spektralen Abhängigkeiten in den Prozessen zu beschreiben, die in Laser-Elektron-Kollisionen bei hohen Energien vorzufinden sind. Diese neue Approximation wird dann auf den Trident- Prozess angewendet und es werden die neuen Strukturen herausgearbeitet, welche durch das breite Spektrum der betrachteten Lichtquelle entstehen. Ferner werden bestehende oder geplante extreme Lichtquellen dahingehend untersucht, in welcher Weise diese, kombiniert mit einem passendem Elektronenstrahl, sensitiv für die vorgestellten spektralen Effekte im Trident-Prozess sind. Abschließend werden weitere mögliche Anwendungsbereiche der neuen Approximation diskutiert.:1 Introduction 1 2 Strong-field quantum electrodynamics 11 2.1 Description of the laser field 12 2.2 Background field approximation 18 2.3 Momentum space rules of strong-field QED 25 2.4 Ward identity and gauge invariance 34 2.5 Strong-field trident process 36 3 Pulsed-perturbative quantum electrodynamics 43 3.1 Approaches and approximations to strong-field QED 43 3.2 Momentum space rules in pulsed-perturbative QED 46 3.3 Spectrum of the background field 52 4 Pulsed-perturbative trident process 57 4.1 Matrixelement and cross section 57 4.2 Total cross section 72 4.3 Inclusive positron distributions 75 4.4 Exclusive electron distributions 81 4.5 Experimental capability 93 5 Summary and Outlook 97 Appendix 101 A Relativistic Kinematics 103 A.1 Preliminary remarks 103 A.2 Coordinate systems 104 A.3 Frames of reference 109 A.4 Kinematics of 2→3 processes 111 B Feynman rules of QED 121 C Perturbative trident pair production 125 C.1 Matrixelement and cross section 125 C.2 Numerical implementation and comparison to literature 129 C.3 Differential cross sections in transverse coordinates 132 C.4 Darkphotons 134 D Useful mathematical statements 139 Bibliography 153 / Modern laser facilities provide highly intense light with a very short temporal structure, which brings the phenomena originally found near the strong radiating stars in the universe into the laboratory. Accordingly, there are, among others, wide theoretical investigations w.r.t. scattering processes of particles impinging this extreme light sources. This has been done by applying the strong-field quantum electrodynamics, which is a theory of electromagnetic interactions within coherent highly intense light treated as a semi-classical background field. For instance, the treatment of the Compton process (inelastic electron- photon scattering) and the Breit-Wheeler process (pair production of a collision of two photons) with strong-field quantum electrodynamics revealed a vast amount of novel non-linear structures and phenomena, which were to some extent experimentally verified. Of particular interest and the central object of investigation within this thesis is also the trident process: a second order process in (strong-field) quantum electrodynamics producing an electron-positron pair within the collision of a photon beam (e.g. produced by a laser) with a counter-propagating electron. However, in the context of highly intense fields, the trident process is more than the product of its parts, the mentioned Compton and Breit-Wheeler process, since the intermediate photon yields both virtual and real contributions producing exceedingly complicated structures. Over the last years, there are several theoretical contributions to the non-linear treatment of the trident process w.r.t. a wide range of laser properties, but the trident process has not yet been fully understood due to its demanding mathematical nature. Within the present thesis, we focus on the dependence of the trident process to the short temporal structures of the involved light source at high energies. Loosely speaking, this means the short pulsed structure of modern light sources provide a wide energy spectrum of the respective photons, which is imprinted on the considered scattering processes. Accordingly, we elaborate a new approximation to strong-field quantum electrodynamics capable to describe the spectral dependence of processes within laser-electron collisions at high energies. Then we apply this new approximation to the trident process and reveal the novel structures generated by the spectrum of the light source. Therefore, we provide an analysis of the spectral impact to the trident process involving the total cross section as well as several inclusive and exclusive distributions of its final particles. Consequently, we examine in principle the experimental capabilities of present or planed extreme light sources by combining them with a suitable electron beam, whether they are sensitive to the encountered spectral effects of the trident process and discuss further applications of the newly introduced approximation.:1 Introduction 1 2 Strong-field quantum electrodynamics 11 2.1 Description of the laser field 12 2.2 Background field approximation 18 2.3 Momentum space rules of strong-field QED 25 2.4 Ward identity and gauge invariance 34 2.5 Strong-field trident process 36 3 Pulsed-perturbative quantum electrodynamics 43 3.1 Approaches and approximations to strong-field QED 43 3.2 Momentum space rules in pulsed-perturbative QED 46 3.3 Spectrum of the background field 52 4 Pulsed-perturbative trident process 57 4.1 Matrixelement and cross section 57 4.2 Total cross section 72 4.3 Inclusive positron distributions 75 4.4 Exclusive electron distributions 81 4.5 Experimental capability 93 5 Summary and Outlook 97 Appendix 101 A Relativistic Kinematics 103 A.1 Preliminary remarks 103 A.2 Coordinate systems 104 A.3 Frames of reference 109 A.4 Kinematics of 2→3 processes 111 B Feynman rules of QED 121 C Perturbative trident pair production 125 C.1 Matrixelement and cross section 125 C.2 Numerical implementation and comparison to literature 129 C.3 Differential cross sections in transverse coordinates 132 C.4 Darkphotons 134 D Useful mathematical statements 139 Bibliography 153

- Master Wenceslas of Trident and mural painting of Bohemian origin in area of Trentino around 1400 This thesis primarily deals with cycles of mural painting associated with so called Master Wenceslas of Trento. This painter has been probably trained in Bohemia, but is attested for the first time at the court of Prince-Bishop of Trento, George of Liechtenstein. The first chapter analyses the current state of research. The history of the Trentino area follows. This part mainly focuses on political relations with Bohemia (2.3) and especially George of Liechtenstein, originally from Moravia (2.4). The following chapters describe individual cycles of painting - the frescoes in Eagl Tower on the castle Buonconsiglio of Trento, the cycle of mural painting in the cemetery chapel in Rifiano, the decoration of the church of St. Charles in Pergine, one scene in the passage under the tower of Meranos Parish Church, and the painting in village Termeno. The analyses of historical sources (8.1) as well as the comparison of each cycle led to the conclusion that the painter was the leader of a court workshop of Bishop George of Liechtenstein, which broke up in 1407. Then Wenceslas left to Merano. Wenceslas' personal style has evident signs of his training in Bohemia during the 70's of the 14th century, his contact...

Yes / This briefing paper is the second in a series to be published during 2007 and 2008 as part of the Bradford Disarmament Research Centre¿s programme on Nuclear-Armed Britain: A Critical Examination of Trident Modernisation, Implications and Accountability.

No

In 1958 the United States and United Kingdom signed the Mutual Defense Agreement which allowed the two countries to share information and technology concerning nuclear weapons. This paper examines the history of this agreement and the Polaris and Trident Sales agreements which followed. The main focus of the paper is the motivating interests of both countries to maintain these agreements today.

Tato diplomová práce se zabývá popisem řiditelnosti specifického robotického hada, který se nazývá trident snake robot. Tento robot je řazen mezi neholonomní systémy. Model je převeden do jazyka diferenciální geometrie a řízen pomocí vektorových polí a operace na nich zavedené (Lieova závorka). Je také uvažována aproximace řídicí distribuce. Dále jsou formulovány pohyby hada ve směru vektorových polí a jejich kombinace, které zajišťují základní pohyby v prostoru (rotace a translace). Tyto pohyby jsou na závěr simulovány v prostředí V-REP.

This master’s thesis describes equations of motion for dynamic model of nonholonomic constrained system, namely the trident robotic snakes. The model is studied in the form of Lagrange's equations and D’Alembert’s principle is applied. Actually this thesis is a continuation of the study going at VUT about the simulations of non-holonomic mechanisms, specifically robotic snakes. The kinematics model was well-examined in the work of of Byrtus, Roman and Vechetová, Jana. So here we provide equations of motion and address the motion planning problem regarding dynamics of the trident snake equipped with active joints through basic examples and propose a feedback linearization algorithm.

Cette thèse a pour objet l'étude de l'interaction laser-matière dans un régime d'éclairement extrême que visent à atteindre plusieurs installations multi-pétawatt en cours de développement (CILEX-Apollon, ELI, IZEST, etc.). Pour un éclairement supérieur à 1022 Wcm-2, la dynamique relativiste des électrons accélérés dans l'onde laser est modiée par un important rayonnement Compton inverse non-linéaire. Au-delà de 1023 Wcm2, les photons ainsi produits peuvent, en interagissant à leur tour avec le champ laser, se désintégrer en paires électron-positron via le mécanisme de Breit-Wheeler non-linéaire. Ces mécanismes d'électrodynamique quantique, dont l'étude expérimentale était jusqu'ici l'apanage des grands accélérateurs de particles, peuvent grandement affecter les mécanismes usuels d'interaction laser-plasma, notamment ceux régissant l'accélération de particules chargées et, par conséquent, le bilan global de l'interaction. Afin de modéliser ce régime inédit d'interaction, qui combine processus collectifs, relativistes et d'électrodynamique quantique, nous avons enrichi des mécanismes précédents le code de simulation particle-in-cell calder développé de longue date au CEA/DIF. L'influence de ces mécanismes est d'abord explorée dans le cas d'une impulsion laser interagissant avec une cible dense de taille micrométrique. Un rendement de conversion de l'énergie laser en photons supérieur à 10% est observée au-dessus de 1023 Wcm-2, tandis que la production d'anti-matière s'emballe, via un mécanisme de cascade, à partir de 1024 Wcm2. Dans un second temps, nous étudions la génération de positrons lors de la collision frontale entre un faisceau d'électrons ultra-relativistes issu d'un accélérateur plasma et une impulsion laser ultra-intense. Dans une dernière partie, nous considérons un scénario prospectif d'intérêt astrophysique, à savoir la collision de plasmas de paires issus de cibles solides irradiées à 1024 Wcm-2 montrant la croissance rapide d'une instabilité de lamentation magnétique combinée à d'intenses effets radiatifs. / This PhD thesis is concerned with the regime of extreme-intensity laser-matter interaction that should be accessed on upcoming multi-petawatt facilities (e.g. CILEX-Apollon, ELI, IZEST). At intensities IL > 1022 Wcm-2, the relativistic dynamics of the laser-driven electrons becomes significantly modified by high-energy radiation emission through nonlinear inverse Compton scattering. For IL > 1023 Wcm-2, the emitted-ray photons can, in turn, interact with the laser field and decay into electron-positron pairs via the nonlinear Breit-Wheeler process. These quantum electrodynamic processes, which until recently could only be explored on large-scale particle accelerators, can greatly alter the "standard" mechanisms of laser-plasma interaction, and therefore its overall energy budget. In order to model their intricate interplay with the laser-induced plasma processes, they have been implemented within the particle-in-cell code calder developed at CEA. In a first part, we study these QED processes in the interaction of an ultra-intense laser with a micrometric overdense target. It is found that the laser-to--ray energy conversion efficiency can by far exceed 10% for intensities IL > 1023 Wcm-2, while copious pair production (through pair cascading) kicks in for IL > 1024 Wcm-2. In a second part, we consider positron generation in the collision between a GeV electron bunch issued from a laser-wake eld accelerator and a counterpropagating laser pulse. In a third part, we analyze a prospective scheme of astrophysical interest, consisting in the collision between two dense pair plasmas produced from solid targets irradiated at 1024 Wcm-2 showing a fast-growing magnetic lamentation instability amplified by intense synchrotron emission.

The aim of this thesis is to describe the development of register records in Bohemia by comparing the recent records in registry books with those issuing from the oldest registry books. It also shows the importance of the register records today and in the past, as well as the changes of these specifications and data through out the centuries. The importance of this thesis is to highlight the fact that the records in the registry books were originally determined to be registers of received sacraments arising from the clerical regulations issued by the Roman Catholic Church. The Trident Council instructed to keep registers of christening and marriages. But the implementation into practise of these registers took longer than it was expected. The register agenda in the Czech lands was not uniform until the 18th century. The proper integration of the register agenda was stated after this period on the basis of state regulations. The Roman Catholic Church contributed actively to the origin of keeping such an agenda and was also entitled and entrusted to supervise the register record of all other Churches.