In this project, an algorithm has been implemented in Python to estimate the parameters describing the production and decay of a spin 1/2 baryon - antibaryon pair. This decay can give clues about a fundamental asymmetry between matter and antimatter. A model-independent formalism developed by the Uppsala hadron physics group and previously implemented in C++, has been shown to be a promising tool in the search for physics beyond the Standard Model (SM) of particle physics. The program developed in this work provides a more user-friendly alternative, and is intended to motivate further use of the formalism through a more maintainable, customizable and readable implementation. The hope is that this will expedite future research in the area of charge parity (CP)-violation and eventually lead to answers to questions such as why the universe consists of matter. A Monte-Carlo integrator is used for normalization and a Python library for function minimization. The program returns an estimation of the physics parameters including error estimation. Tests of statistical properties of the estimator, such as consistency and bias, have been performed. To speed up the implementation, the Just-In-Time compiler Numba has been employed which resulted in a speed increase of a factor 400 compared to plain Python code.

Ce travail porte sur la reconnaissance de sols à faible profondeur grâce aux données de résistance de pointe recueillies à l'aide de l'essai de pénétration dynamique à énergie variable, Panda®. L'objectif principal est d'étudier et de proposer un ensemble d'approches dans le cadre d'une méthode globale permettant d'exploiter les mesures issues d'une campagne de sondages Panda afin de bâtir un modèle géotechnique du terrain.Ce manuscrit est structuré en quatre parties, chacune abordant un objectif spécifique :dans un premier temps, on rappelle les principaux moyens de reconnaissance des sols, notamment l'essai de pénétration dynamique Panda. Ensuite on réalise un bref aperçu sur le modèle géotechnique et les techniques mathématiques pour décrire l'incertitude dans la caractérisation des propriétés du sol;la deuxième partie porte sur l'identification automatique des unités homogènes du terrain, à partir du signal pénétrométrique Panda. Suite à l'étude réalisée sur l'identification "experte" des couches à partir du signal Panda, des approches statistiques basées sur une fenêtre glissante ont été proposées. Ces techniques ont été étudiées et validées sur la base d'un protocole d'essais en laboratoire et sur des essais effectués en sites naturels et en conditions réelles;la troisième partie porte sur l'identification automatique des matériaux composant les unités homogènes détectées dans le signal Panda à partir des méthodes proposées en partie II. Une méthode de classification automatique basée sur des réseaux de neurones artificiels a été proposée et appliquée aux deux cas d'étude : la caractérisation de sols naturels et la classification d'un matériau granulaire argileux industrialisé (bentonite) ; enfin, la dernière partie est consacrée à la production d'un modèle de terrain basé sur la modélisation et la simulation de la résistance de pointe dynamique au moyen de fonctions aléatoires de l'espace. Cette modélisation est basée sur une approche par champs aléatoires conditionnés par les sondages Panda du terrain. Sa mise en œuvre a été étudiée pour un terrain expérimental situé dans la plaine deltaïque méditerranéenne en Espagne. Des études complémentaires en vue de raffiner cette démarche ont été réalisées pour un deuxième site expérimental dans la plaine de la Limagne en France. / This research focuses on the site characterization of shallow soils using the dynamic cone penetrometer Panda® which uses variable energy. The main purpose is to study and propose several techniques as part of an overall method in order to obtain a ground model through a geotechnical campaign based on the Panda test.This work is divided into four parts, each of them it is focused on a specific topic :first of all, we introduce the main site characterization techniques, including the dynamic penetrometer Panda. Then, we present a brief overview of the geotechnical model and the mathematical methods for the characterization of uncertainties in soil properties;the second part deals with the automatic identification of physical homogeneous soil units based on penetration's mechanical response of the soil using the Panda test. Following a study about the soil layers identification based only on expert's judgment, we have proposed statistical moving window procedures for an objective assessment. The application of these statistical methods have been studied for the laboratory and in situ Panda test;the third part focuses on the automatic classification of the penetrations curves in the homogeneous soil units identified using the statistical techniques proposed in part II. An automatic methodology to predict the soil grading from the dynamic cone resistance using artificial neural networks has been proposed. The framework has been studied for two different research problems: the classification of natural soils and the classification of several crushed aggregate-bentonite mixtures;finally, the last chapter was devoted to model the spatial variability of the dynamic cone resistance qd based on random field theory and geostatistics. In order to reduce uncertainty in the field where Panda measurements are carried out, we have proposed the use of conditional simulation in a three dimensional space. This approach has been applied and studied to a real site investigation carried out in an alluvial mediterranean deltaic environment in Spain. Complementary studies in order to improve the proposed framework have been explored based on another geotechnical campaign conducted on a second experimental site in France.

Dans la pratique actuelle du génie géotechnique, les essais de pénétration tels que les CPT, SPT, Panda sont largement utilisés pour caractériser mécaniquement les sols, au travers notamment d’une caractéristique de rupture appelée résistance de pointe. Par ailleurs, les dernières évolutions technologiques apportées aux essais de pénétration dynamique (Panda 3) permettent d’obtenir pendant chaque impact une courbe charge–enfoncement donnant la charge en pointe en fonction de l’enfoncement à partir de la mesure et du découplage des ondes générées durant l’essai. L’exploitation de cette nouvelle courbe fournit des informations non seulement sur la résistance de pointe dynamique mais également sur des paramètres mécaniques complémentaires mis en jeu pendant l’enfoncement de la pointe. L’objectif de cette thèse est de développer un modèle numérique en 2D capable de reproduire les signaux pénétrométriques obtenus expérimentalement par essais de type statique ou dynamique. Ce modèle est basé sur la méthode des éléments discrets avec une loi de contact linéaire simple. Une fois le modèle validé, une étude paramétrique a été réalisée en jouant essentiellement sur les modes d’application de la sollicitation (vitesse d’impact ou de pénétration), la granulométrie du matériau ainsi que l’arrangement granulaire (variation de la densité). Outre l’influence de ces paramètres sur les signaux pénétrométriques et la résistance de pointe mesurée, une attention particulière est portée sur l’analyse micromécanique : dissipation d’énergie dans le milieu, évolution des chaines de force, orientations des contacts. Cette analyse nécessite de développer des outils numériques spécifiques afin de mieux comprendre le mécanisme de l’enfoncement et tenter d’expliquer la réponse mécanique macroscopique obtenue. L’effet de la vitesse n’influence significativement que sur les essais de pénétration statiques et dynamiques en régime d’écoulement dense. A vitesse d’enfoncement comparable, il n’y a aucune différence significative au niveau microscopique entre les deux modes de sollicitation statique et dynamique. En ce qui concerne l’influence des caractéristiques du matériau, les résultats obtenus par le modèle numérique conforment aux celui réel lors que le frottement entre particules ou la compacité du milieu varie. Concernant la granulométrie, la variation de la courbe charge-enfoncement et la force de pointe dynamique augmente lorsque le diamètre moyen augmente. / In the field of in situ mechanical characterization of soils, penetration tests are commonly used. Penetration tests measure the properties of soils in the domain of large deformations. The tip resistances, deduced from pile driving theory, can be measured either in dynamic conditions (q d ) either in static conditions (q c ). Recently, the measurement technique in dynamic conditions has been improved and it is now possible to record the whole response of the soil during one impact in terms of tip force and penetration distance. The exploitation of this new curve provides information not only on dynamic tip resistance but also on additional mechanical parameters involved during the driving of the tip. The objective of this work is to develop a numerical model in 2D able to reproduce the penetrometric record obtained experimentally by static or dynamic penetration tests. This model is based on the discrete element method with a simple linear contact model. After the validation of the model, a parametric study was performed essentially on the loading type (static or dynamic), the penetration rate, the particle size of the granular material and the arrangement (density variation). Besides the influence of these parameters on the penetrometer signals and the tip resistance, a particular attention was focused on micromechanical analysis: energy dissipation in the medium, force chain evolution, contact orientation. This analysis requires the development of specific numerical tools to better understand the penetration mechanism and try to explain the macroscopic mechanical response obtained. The penetration rate influences significantly only in the dense flow regime on the static and dynamic penetration tests. There is no significant microscopic difference between static and dynamic penetration tests with similar penetration rates. Regarding the influence of the characteristics of the material, the numerical results obtained conform to the real results when the particle friction or the compactness of the medium varies. Concerning the particle size, the dynamic signal variation and the dynamic tip force increases when the average particle diameter increases.

Ce travail présente les développements récents réalisés sur le pénétromètre PANDA 3. Il s'agit d'un pénétromètre dynamique instrumenté qui permet à partir de la mesure puis du découplage des ondes créées par l’impact sur l’appareil, d’obtenir pour chaque coup une courbe charge-enfoncement σp-sp du sol ausculté. L’exploitation de cette courbe permet de déterminer des paramètres de résistance (résistance de pointe qd), de déformation (module dynamique Ed P3), des caractéristiques d’amortissement Js et de célérité d'ondes (CsP3 et CpP3) des sols auscultés en fonction de la profondeur tout au long du sondage. Cependant, et bien que la méthode soit très intéressante, celle-ci est restée au stade d’un prototype de laboratoire. Il est donc nécessaire de réaliser une étude plus approfondie sur l'essai lui-même et sur l’information contenue dans la courbe σp-sp en vue de fiabiliser la mesure et d’améliorer son exploitation. Dans un premier temps, nous présentons un bref aperçu sur les techniques de reconnaissance géotechnique et plus particulièrement celle des essais de pénétration dynamique. Le principe général du PANDA 3 est également présenté. La deuxième partie est consacrée au développement d'un nouveau prototype de pénétromètre PANDA 3. Ce développement s’appuie sur plusieurs études visant à valider la qualité des informations recueillies, leur bonne reproductibilité et le traitement des signaux d’acquisition. De même, un modèle numérique discret du battage pénétrométrique développé à l’aide du logiciel Particle Flow Code (Itasca) est présenté permettant de valider la technique de mesure. La troisième partie traite d'une étude comparative des résultats obtenus avec le PANDA 3 et d’autres techniques d'auscultation in situ afin de valider les résultats obtenus et l’utilisation de l’appareil dans des conditions réelles. Par ailleurs l’extension de cette technique de mesure au cas des pénétromètres lourds est appliquée dans le but de mesurer l'énergie transmise et d’étalonner le système de battage. Enfin, la dernière partie est consacrée à l'interprétation et l'exploitation des signaux en pointe afin d'affiner le modèle d'interprétation de la courbe charge-enfoncement. L'analyse de l'ensemble des signaux enregistrés au laboratoire a permis d’approcher une méthodologie d'exploitation de la courbe. L'application de la méthode proposée a été réalisée pour différents sols aussi bien au laboratoire que sur le terrain. Les résultats obtenus ont été confrontés avec d'autres types d’essais. / This work presents the recent developments made on the penetrometer PANDA®3. The instrumented dynamic penetrometer allowing, from the measurement and the decoupling of waves created by the impact, to obtain the load-penetration curve σp-sp of the soil. The exploitation of this curve allows determining the failure parameter (tip resistance qd), deformation (dynamic modulus EdP3), damping characteristics (Js) and wave speed (CsP3 and CpP3) of the investigated soil according to depth all along the sounding. However, although the proposed method is very interesting, it has remained at the stage of a laboratory prototype. It is therefore necessary to conduct a more thorough study of the test itself and the information provided from the σp-sp curve in order to obtain reliable measurement and improve their exploitation. First of all, we are presenting a brief overview of the geotechnical in-situ testing particularly that of the dynamic penetration tests as well as the general principle of PANDA 3 is presented. The second part is devoted to the development of a new prototype of the PANDA 3 penetrometer. This development is based on several studies aiming at validating the quality of the information, good reproducibility and treatment of the acquisition signals. Similarly, a discrete numerical model of the penetrometer developed using the Particle Flow Code software (Itasca) is presented to validate the measurement technique. The third part deals with a comparative study of the results obtained with the PANDA 3 and other in situ investigation techniques to validate the obtained results and the use of the device in real conditions. Moreover, the extension of this measurement technique in the case of heavy penetrometer is applied in order to measure the transmitted energy and to calibrate the driving system. The last part is devoted to refining the interpretation and exploitation of the load-penetration curve. The analysis of all the signals recorded in the laboratory allowed to approach a methodology of curve exploitation. The application of the proposed method was carried out for different soils both in the laboratory and on field. The results were confronted with other types of tests.

<p>The PANDA experiment is a part of the future FAIR accelerator facility and will study the strong interaction by detecting the reaction products from antiproton-proton annihilations in a near full solid-angle configuration. One option for the internal proton target in PANDA is frozen micro-spheres of hydrogen, so-called pellets.</p><p>Such a pellet target is interesting because of the unique characteristics it offers; the high target thickness, the small interaction volume, the minimal gas load on the vacuum system, and the possibility of tracking individual pellets. Nevertheless, it is possible to allocate the bulky equipment needed to produce the pellets at a few meters away from the beam. This way particle detectors can be located close and almost fully around the interaction point.</p><p>This thesis is devoted to the optimization of a pellet target. To perform measurements, a Pellet-Test Station was built at The Svedberg Laboratory, Uppsala. For the first time, experimental results show the pellet distribution in space and time, and in addition, the vacuum along the pellet pipes. Furthermore, dedicated measurements carried out at CELSIUS/WASA demonstrate the existence of pellet heating as a result of beam-target interactions.</p><p>In performing calculations, the potential problems with pellet heating at PANDA are outlined. Moreover, to look at the consequences for the desired physics, a reaction involving short-lived D-mesons has been used to show the advantages of pellets compared to a more spacious target.</p><p>In conclusion, these studies lead to a deeper understanding of the pellet properties, which makes it possible to suggest future improvements, such as cooling with no vibrations.</p>

<p>This thesis treats the mass range of charmonium states and excited gluonic fields in two experiments, BESII and PANDA, and outlines a phenomenological model that connects them.</p><p>In BESII, <i>e</i>⁺<i>e</i>^– form a charmonium initial state, which is utilised as a source for secondary particles. The analysed channels, <i>ψ</i>´→ <i>γK</i>⁺<i>K</i>^– and <i>ψ</i>´→ <i>γπ</i>⁺<i>π</i>^–, give access to intermediate scalar states such as the two glueball candidates: f₀(1500) and f₀(1710). The f₀(1710) is indeed observed in decay into both <i>π</i>⁺<i>π</i>^– and <i>K</i>⁺<i>K</i>^– and the f₀(1500) is accepted as a necessary part of the <i>π</i>⁺<i>π</i>^– signal at the moderate 5% level. In addition, we observe the two tensor states f₂(1270) (in both channels) and f₂´(1525) (in <i>K</i>⁺<i>K</i>^–), but the need for the f₂´(1525) is not firmly established. The region around 2 GeV/<i>c</i>² is fitted with an f₄(2050) and an f₀(2200) in <i>π</i>⁺<i>π</i>^–. This region is fairly flat in <i>K</i>⁺<i>K</i>^– with a slight peak at the f₀(2200). Branching ratios for all eight channels are given. A fit to the angular distribution of ψ´→ γ f₂(1270) → <i>γ π</i>⁺<i>π</i>^–gave two possible solutions for the relative importance of helicity projections zero, one and two.</p><p>The future <i>pp</i>bar experiment PANDA is still in the development phase; important physics goals have been defined and we are now taking on the laborious task of constructing a detector that is able to fulfil them. A simulation investigation of a theoretically preferred <i>J</i><i>PC</i>=1^–+ charmonium hybrid (<i>H</i><i>c</i>) is presented: <i>ppbar</i> → <i>H</i><i>c</i><i>π</i>⁰/<i>η</i>, <i>H</i><i>c</i> → <i>χ</i><i>c</i>₁ (<i>π</i>⁰<i>π</i>⁰)<i>S–wave</i>, <i>χ</i><i>c</i>₁ → <i>J</i>/<i>ψπ</i>⁰, with a final state of seven photons and a lepton pair. To detect this channel next to full coverage of CM phase space is needed and as little material as possible before the electromagnetic calorimeter. </p><p>A second simulation study of <i>pp</i>bar → <i>η</i><i>c</i> → <i>γγ</i> at PANDA, suggests that the channel should be possible to detect with a signal-to-background ratio of 5±1 and a detection efficiency of at least 10%. </p><p>By assuming a constant matrix element we obtain a relation between the decay width for <i>ψ</i> → <i>pp</i>bar+<i>m</i>, which has been measured at BES for several cases, and the cross section for <i>pp</i>bar charmonium production in association with the same light meson, <i>m</i> (at for example PANDA). Cross sections of ~300–3000 pb were predicted for J/ψ production and ~30 pb for <i>ψ</i>' production. Isoscalars seem to be preferred to isovectors in <i>J</i>/<i>ψ</i> production, this might however be an artefact of simplifications within the model. A comparison with the only measured cross section, <i>pp</i>bar → <i>J</i>/<i>ψπ</i>⁰, suggests that the model is useful as a first estimate.</p>

The PANDA experiment is a part of the future FAIR accelerator facility and will study the strong interaction by detecting the reaction products from antiproton-proton annihilations in a near full solid-angle configuration. One option for the internal proton target in PANDA is frozen micro-spheres of hydrogen, so-called pellets. Such a pellet target is interesting because of the unique characteristics it offers; the high target thickness, the small interaction volume, the minimal gas load on the vacuum system, and the possibility of tracking individual pellets. Nevertheless, it is possible to allocate the bulky equipment needed to produce the pellets at a few meters away from the beam. This way particle detectors can be located close and almost fully around the interaction point. This thesis is devoted to the optimization of a pellet target. To perform measurements, a Pellet-Test Station was built at The Svedberg Laboratory, Uppsala. For the first time, experimental results show the pellet distribution in space and time, and in addition, the vacuum along the pellet pipes. Furthermore, dedicated measurements carried out at CELSIUS/WASA demonstrate the existence of pellet heating as a result of beam-target interactions. In performing calculations, the potential problems with pellet heating at PANDA are outlined. Moreover, to look at the consequences for the desired physics, a reaction involving short-lived D-mesons has been used to show the advantages of pellets compared to a more spacious target. In conclusion, these studies lead to a deeper understanding of the pellet properties, which makes it possible to suggest future improvements, such as cooling with no vibrations.

This thesis treats the mass range of charmonium states and excited gluonic fields in two experiments, BESII and PANDA, and outlines a phenomenological model that connects them. In BESII, e+e– form a charmonium initial state, which is utilised as a source for secondary particles. The analysed channels, ψ´→ γK+K– and ψ´→ γπ+π–, give access to intermediate scalar states such as the two glueball candidates: f0(1500) and f0(1710). The f0(1710) is indeed observed in decay into both π+π– and K+K– and the f0(1500) is accepted as a necessary part of the π+π– signal at the moderate 5% level. In addition, we observe the two tensor states f2(1270) (in both channels) and f2´(1525) (in K+K–), but the need for the f2´(1525) is not firmly established. The region around 2 GeV/c2 is fitted with an f4(2050) and an f0(2200) in π+π–. This region is fairly flat in K+K– with a slight peak at the f0(2200). Branching ratios for all eight channels are given. A fit to the angular distribution of ψ´→ γ f2(1270) → γ π+π–gave two possible solutions for the relative importance of helicity projections zero, one and two. The future ppbar experiment PANDA is still in the development phase; important physics goals have been defined and we are now taking on the laborious task of constructing a detector that is able to fulfil them. A simulation investigation of a theoretically preferred JPC=1–+ charmonium hybrid (Hc) is presented: ppbar → Hcπ0/η, Hc → χc1 (π0π0)S–wave, χc1 → J/ψπ0, with a final state of seven photons and a lepton pair. To detect this channel next to full coverage of CM phase space is needed and as little material as possible before the electromagnetic calorimeter. A second simulation study of ppbar → ηc → γγ at PANDA, suggests that the channel should be possible to detect with a signal-to-background ratio of 5±1 and a detection efficiency of at least 10%. By assuming a constant matrix element we obtain a relation between the decay width for ψ → ppbar+m, which has been measured at BES for several cases, and the cross section for ppbar charmonium production in association with the same light meson, m (at for example PANDA). Cross sections of ~300–3000 pb were predicted for J/ψ production and ~30 pb for ψ' production. Isoscalars seem to be preferred to isovectors in J/ψ production, this might however be an artefact of simplifications within the model. A comparison with the only measured cross section, ppbar → J/ψπ0, suggests that the model is useful as a first estimate.

The prevalence of play in the animal kingdom makes it a well-studied phenomenon, yet little is known about play fighting behavior in bears. I investigated the effects of sex, partner (dam or cub), and early rearing conditions on play fighting behavior in giant panda cubs by observing video tapes that were recorded at two facilities in China over a three-year period. Two of the three factors, sex and partner, had significant effects on the play fighting behavior of giant panda cubs. I found sex differences in play fighting, with males exhibiting significantly higher rates of biting behavior than females during play bouts with other cubs. This lends support to the motor training hypothesis and suggests that there is a relationship between adult roles and earlier play fighting behavior. Partner had a significant effect on play fighting, in that cubs exhibited significantly higher rates of Bite, Break Away, Paw Swat, and Re-engage behaviors during play bouts with cubs. These differences suggest that cubs and dams might provide different opportunities as partners during play fighting bouts. Because some behaviors occurred at higher rates with dams, it is possible that dams engage in self-handicapping behavior during play fighting bouts with cubs. Early rearing conditions did not have significant effects on behaviors when they were examined by category or by individual behaviors. Similar results were found when cubs that had access to adult females after six months of age were excluded from the analyses. These results suggest that early rearing conditions have little effect on the play fighting behavior of captive giant panda cubs. Certain aspects of giant panda behavioral ecology, however, might contribute to stability in play signals, regardless of early rearing conditions. Future studies of play fighting behavior in bears should further examine these and other factors, and that data from these studies need to be interpreted in light of the relationship of bears to other carnivores.