In this thesis, the possibility of enabling space-mining for the upcoming decade is explored. Making use of recently-proven reusable rockets, we envision a fleet of spacecraft capable of reaching Near-Earth asteroids. To analyze this idea, the goal of this problem is to maximize the asteroid mass retrieved within a spacecraft max life span. Explicitly, the maximum lifetime of the spacecraft fleet is set at 30 years. A fuel supply-chain is proposed and designed so that each spacecraft is refueled before departing for each asteroid. To maximize access to the number of asteroids and retrievable mass for each mission, we propose launching each mission from an orbit with low escape velocity. The L2-Halo orbit at the libration point in the Earth-Moon system was selected due to its easy access from Low-Earth Orbit and for a cislunar synergy with NASA Gateway. Using data from NASA SmallBody and CNEOS databases, we investigated NEAs in the period between 2030 and 2060 could be captured in the ecliptic plane and returned to L2-Halo with two approaches, MARM-1 and MARM-2. Together, these databases provide all information for every asteroid's close approach known today. Returning the asteroid as a whole is explored in the MARM-1 method, while MARM-2 evaluates the possibility of reaching larger asteroids and returning a fragment of their masses, such that it optimizes the available cargo weight per time of flight of each mission. The following results are compared with previous work from the community. The results show a 96% reduction in the cost per kg, with an enormous increase in retrieved mass. With these results, this thesis shows that not solely energy or dynamic optimization will be responsible for proving space mining feasibility, but rather a combination of those and business best practices. Proving feasibility for space mining is a complex and immense problem. Although this thesis opens new possibilities for future work on the field and sparkes the interest of private endeavors, the final solution for this problem still requires additional exploration. / M.S. / In this thesis, the possibility of enabling space-mining for the upcoming decade is explored. Making use of recently-proven reusable rockets, we envision a fleet of spacecraft capable of reaching Near-Earth asteroids, NEAs. To analyze this idea, the goal of this problem is to maximize the asteroid mass retrieved within a spacecraft max life span. Explicitly, the maximum lifetime of the spacecraft fleet is set at 30 years. A fuel supply-chain is proposed and designed so that each spacecraft is refueled before departing for each asteroid. To maximize access to the number of asteroids and retrievable mass for each mission, we propose launching each mission from an orbit with low escape velocity. A location after the Moon, at the L2-Halo orbit, was selected due to its easy access from Low-Earth Orbit and for a synergy with the proposed new space station at the Moon orbit. Using data from NASA databases, we investigated the asteroids in the period between 2030 and 2060 that could be captured and returned with two approaches, MARM-1 and MARM-2. Together, these databases provide all information for every asteroid's close approach known today. Returning the asteroid as a whole is explored in the MARM-1 method, while MARM-2 evaluates the possibility of reaching larger asteroids and returning a fragment of their masses, such that it optimizes the available cargo weight per time of flight of each mission. The following results are compared with previous work from the community. The results show a 96% reduction in the cost per kg, with an enormous increase in retrieved mass. With these results, this thesis shows that not solely energy or dynamic optimization will be responsible for proving space mining feasibility, but rather a combination of those and business best practices. Proving feasibility for space mining is a complex and immense problem. Although this thesis opens new possibilities for future work on the field and sparkes the interest of private endeavors, the final solution for this problem still requires additional exploration.

L'hydrogène moléculaire diffus et froid peut être l'un des candidats ultimes à la composante baryonique cachée de la Voie Lactée. Nous décrivons une nouvelle voie de recherche de matière transparente dans le disque et le halo galactiques, qui exploite les effets de diffraction et de réfraction de la lumière des étoiles d'arrière-plan. En simulant le retard de phase induit par un milieu turbulent, nous avons calculé la figure d'éclairement sur la terre d'une source étendue pour une bande passante donnée. Nous montrons que dans les cas favorables, la luminosité apparente d'une étoile d'arrière-plan peut être soumise à des fluctuations stochastiques de l'ordre de quelques pour cent sur une échelle de temps caractéristique de quelques minutes. Nous avons recherché de tels effets de scintillation, induits par du gaz moléculaire de nébuleuses visibles (sombres), ainsi que par d'hypothétiques (invisibles) clumpuscules d'hydrogène moléculaire froid du halo, pendant deux nuits avec le détecteur infra-rouge SOFI au foyer du télescope NTT de l'ESO. Parmi les quelques milliers d'étoiles surveillées, nous avons détecté un objet dont les variations sont compatibles avec un fort effet de scintillation à travers une structure turbulente de la nébuleuse B68. Comme par ailleurs aucun effet de scintillation n'a été trouvé vers le Petit Nuage de Magellan, nous sommes en mesure d'établir des limites supérieures sur la contribution des clumpuscules de gaz à la masse du halo galactique. Nous montrons qu'une surveillance à cadence élevée dans la bande visible avec un télescope de diamètre supérieur à quatre mètres équipé d'une caméra à lecture rapide devrait permettre, avec une exposition de quelque millions (d'heures x étoiles), de quantifier ou de borner d'une façon très significative la contribution du gaz moléculaire turbulent au halo Galactique. / Cool molecular hydrogen H2 may be the ultimate possible constituent to the Milky-Way missing baryon. We describe a new way to search for such transparent matter in the Galactic disc and halo, through the diffractive and refractive effects on the light of background stars. By simulating the phase delay induced by a turbulent medium, we computed the corresponding illumination pattern on the earth for an extended source and a given passband. We show that in favorable cases, the light of a background star can be subjected to stochastic fluctuations of the order of a few percent at a characteristic time scale of a few minutes. We have searched for scintillation induced by molecular gas in visible dark nebulae as well as by hypothetical halo clumpuscules of cool molecular hydrogen (H2_He) during two nights, using the NTT telescope and the IR SOFI detector. Amongst a few thousands of monitored stars, we found one light-curve that is compatible with a strong scintillation effect through a turbulent structure in the B68 nebula. Because no candidate were found toward the SMC, we are able to establish upper limits on the contribution of gas clumpuscules to the Galactic halo mass. We show that the short time-scale monitoring of a few 10^6 star _ hour in the visible band with a >4 m telescope and a fast readout camera should allow one to interestingly quantify or constrain the contribution of turbulent molecular gas to the Galactic halo.

Cette thèse, écrite en anglais, étudie la non-Gaussianité (NG) des avant-plans extragalactiques au fond de rayonnement fossile (FDC), celui-ci étant une des observables de choix de la cosmologie actuelle. Ces dernières années a émergé la recherche de déviations du FDC à la loi Gaussienne, car elles permettraient de discriminer les modèles de génération des perturbations primordiales. Cependant les mesures du FDC, e.g. par le satellite Planck, sont contaminées par différents avant-plans. J'ai étudié en particulier les avant-plans extragalactiques traçant la structure à grande échelle de l'univers: les sources ponctuelles radio et infrarouges et l'effet Sunyaev-Zel'dovich thermique (tSZ). Je décris donc les outils statistiques caractérisant un champ aléatoire : les fonctions de corrélations, et leur analogue harmonique : les polyspectres. En particulier le bispectre est l'indicateur de plus bas ordre de NG avec le plus fort rapport signal sur bruit (SNR) potentiel. Je décris comment il peut être estimé sur des données en tenant compte d'un masque (e.g. galactique), et propose une méthode de visualisation du bispectre plus adaptée que les préexistantes. Je décris ensuite la covariance d'une mesure de polyspectre, une méthode pour générer des simulations non-Gaussiennes, et comment la statistique d'un champ 3D se projette sur la sphère lors de l'intégration sur la ligne de visée. Je décris ensuite la genèse des perturbations de densité par l'inflation standard et leur possible NG, comment elles génèrent les anisotropies du FDC et croissent pour former la structure à grande échelle de l'univers actuel. Pour décrire cette dite structure, j'expose le modèle de halo et propose une méthode diagrammatique pour calculer les polyspectres du champ de densité des galaxies et avoir une représentation simple et puissante des termes impliqués. Puis je décris les avant-plans au FDC, tant galactiques que extragalactiques. J'expose la physique de l'effet tSZ et comment décrire sa distribution spatiale avec le modèle de halo. Puis je décris les sources extragalactiques et présente une prescription pour la NG de sources corrélées. Pour le fond diffus infrarouge (FDI) j'introduis une modélisation physique par le modèle de halo et la méthode diagrammatique. Je calcule numériquement le bispectre 3D des galaxies et obtiens la première prédiction du bispectre angulaire FDI. Je montre les différentes contributions et l'évolution temporelle du bispectre des galaxies. Pour le bispectre du FDI, je montre ses différents termes, sa dépendence en échelle et en configuration, et comment il varie avec les paramètres du modèle. Par analyse de Fisher, je montre qu'il apporte de fortes contraintes sur ces paramètres, complémentaires ou supérieures à celles venant du spectre. Enfin, je décris mon travail de mesure de la NG. J'introduis d'abord un estimateur pour l'amplitude du bispectre FDI, et montre comment le combiner avec de similaires pour les sources radio et le FDC, pour une contrainte jointe des différentes sources de NG. Je quantifie la contamination des sources ponctuelles à l'estimation de NG primordiale ; pour Planck elle est négligeable aux fréquences centrales du FDC. Je décris ensuite ma mesure du bispectre FDI sur les données Planck ; il est détecté très significativement à 217, 353 et 545 GHz, avec des SNR allant de 5.8 à 28.7. Sa forme est cohérente entre les différentes fréquences, de même que l'amplitude intrinsèque de NG. Enfin, je décris ma mesure du bispectre tSZ, sur des simulations et sur les cartes tSZ estimées par Planck, validant la robustesse de l'estimation via des simulations d'avant-plans. Le bispectre tSZ est détecté avec un SNR~200. Son amplitude et sa dépendence en échelle et en configuration sont cohérentes avec la carte des amas détectés et avec les simulations. Enfin, cette mesure place une contrainte sur les paramètres cosmologiques : sigma_8 (Omega_b/0.049)^0.35 = 0.74+/-0.04 en accord avec les autres statistiques tSZ. / This PhD thesis, written in english, studies the non-Gaussianity (NG) of extragalactic foregrounds to the Cosmic Microwave Background (CMB), the latter being one of the golden observables of today's cosmology. In the last decade has emerged research for deviations of the CMB to the Gaussian law, as they would discriminate the models for the generation of primordial perturbations. However the CMB measurements, e.g. by the Planck satellite, are contaminated by several foregrounds. I studied in particular the extragalactic foregrounds which trace the large scale structure of the universe : radio and infrared point-sources and the thermal Sunyaev-Zel'dovich effect (tSZ). I hence describe the statistical tools to characterise a random field : the correlation functions, and their harmonic counterpart : the polyspectra. In particular the bispectrum is the lowest order indicator of NG, with the highest potential signal to noise ratio (SNR). I describe how it can be estimated on data, accounting for a potential mask (e.g. galactic), and propose a method to visualise the bispectrum, which is more adapted than the already existing ones. I then describe the covariance of a polyspectrum measurement, a method to generate non-Gaussian simulations, and how the statistic of a 3D field projects onto the sphere when integrating along the line-of-sight. I then describe the generation of density perturbations by the standard inflation model and their possible NG, how they yield the CMB anisotropies and grow to form the large scale structure of today's universe. To describe this large scale structure, I present the halo model and propose a diagrammatic method to compute the polyspectra of the galaxy density field and to have a simple and powerful representation of the involved terms. I then describe the foregrounds to the CMB, galactic as well as extragalactic. I briefly describe the physics of the thermal Sunyaev-Zel'dovich effect and how to describe its spatial distribution with the halo model. I then describe the extragalactic point-sources and present a prescription for the NG of clustered sources. For the Cosmic Infrared Background (CIB) I introduce a physical modeling with the halo model and the diagrammatic method. I compute numerically the 3D galaxy bispectrum and produce the first theoretical prediction of the CIB angular bispectrum. I show the contributions of the different terms and the temporal evolution of the galaxy bispectrum. For the CIB angular bispectrum, I show its different terms, its scale and configuration dependence, and how it varies with model parameters. By Fisher analysis, I show it allows very good constraints on these parameters, complementary to or better than those coming from the power spectrum. Finally, I describe my work on measuring NG. I first introduce an estimator for the amplitude of the CIB bispectrum, and show how to combine it with similar ones for radio sources and the CMB, for a joint constraint of the different sources of NG. I quantify the contamination of extragalactic point-sources to the estimation of primordial NG ; for Planck it is negligible for the central CMB frequencies. I then describe my measurement of the CIB bispectrum on Planck data ; it is very significantly detected at 217, 353 and 545 GHz with SNR ranging from 5.8 to 28.7. Its shape is consistent between frequencies, as well as the intrinsic amplitude of NG. Ultimately, I describe my measurement of the tSZ bispectrum, on simulations and on Compton parameter maps estimated by Planck, validating the robustness of the estimation thanks to realist foreground simulations. The tSZ bispectrum is very significantly detected with SNR~200. Its amplitude and its scale and configuration dependence are consistent with the projected map of detected clusters and tSZ simulations. Finally, this measurement allows to put a constraint on the cosmological parameters : sigma_8*(Omega_b/0.049)^0.35 = 0.74+/-0.04 in agreement with other tSZ statistics.

The research described in this thesis originated from an idea to develop new body protection for the sport of fencing. The ultimate goal is to develop body armour which would be flexible, wearable, washable, light and breathable, offer protection from injuries and cover the entire body of a sportsman. A new material which exhibits shear thickening behaviour has been specially developed for this purpose in the process of this investigation. The material was designed and synthesised as a soft polymeric system which is flexible, chemically stable and able to increase the value of its modulus of elasticity upon impact at a high strain rate, while remaining in its soft gel-like elastomeric state when low strain rate deformation is applied. The polymeric system that has been developed is based on interpenetrating polymeric networks (IPN) of immiscible polyurethane/urea-ester/ether and poly(boron)n(dimethylsiloxane)m (where on average m ≈ 16 n). In addition, as the polydimethylsilane (PDMS) based polymeric system strongly tends to phase separation, the siloxane polymeric network was chemically cross-linked to the polyurethane polymeric network through polyurethane chemical cross-link-bridges. In order to introduce polyurethane cross-links to a siloxane-based polymeric network, some of the attached methyl groups in the PDMS polymeric backbone were substituted by ε-pentanol groups. The resulting polymeric system combines properties of an alternating copolymer with IPN. The actual substitution of the methyl groups of PDMS into alternating ε-pentanol groups was performed by Grignard reaction of trifunctional chlorosilane monomers, magnesium and 1,5-dibromopentane. Chemical analytical techniques like FT-IR, 13C NMR and 1H NMR spectroscopy were used to reveal the chemical structure of the synthesised polymeric network. The mechanical and dynamical properties of the obtained polymeric system were analysed by dynamic mechanical analysis (DMA). This part of the investigation indicated that the novel polymeric system exhibited shear thickening behaviour, but only at a narrow diapason of deformations (i.e., deformations between 2 to 3 % of the length of the sample). At this limited diapason of deformation an effective increase of the modulus of elasticity from 6 MPa (at lower frequencies, i.e., up to ≤6 Hz of the applied oscillating stress) to 65 MPa (at frequencies between 12.5 to 25 Hz) was obtained. However, no increase in the modulus of elasticity was recorded at deformations below 1.5 % or above 3.5 % of length of the sample at the same frequencies (0 to 25Hz) of the applied oscillating stress.

Cool molecular hydrogen H2 may be the ultimate possible constituent to the Milky-Way missing baryon. We describe a new way to search for such transparent matter in the Galactic disc and halo, through the diffractive and refractive effects on the light of background stars. By simulating the phase delay induced by a turbulent medium, we computed the corresponding illumination pattern on the earth for an extended source and a given passband. We show that in favorable cases, the light of a background star can be subjected to stochastic fluctuations of the order of a few percent at a characteristic time scale of a few minutes. We have searched for scintillation induced by molecular gas in visible dark nebulae as well as by hypothetical halo clumpuscules of cool molecular hydrogen (H2_He) during two nights, using the NTT telescope and the IR SOFI detector. Amongst a few thousands of monitored stars, we found one light-curve that is compatible with a strong scintillation effect through a turbulent structure in the B68 nebula. Because no candidate were found toward the SMC, we are able to establish upper limits on the contribution of gas clumpuscules to the Galactic halo mass. We show that the short time-scale monitoring of a few 10^6 star _ hour in the visible band with a >4 m telescope and a fast readout camera should allow one to interestingly quantify or constrain the contribution of turbulent molecular gas to the Galactic halo.

Shea Creek est un gisement d'uranium liée à la discordance entre un socle métamorphique et des roches sédimentaires d'origine fluviatile, d'âge Paléo-protérozoïque et situé dans la partie ouest du bassin d'Athabasca. Ce gisement majeur est le plus profond connu actuellement dans le bassin (entre 680 m et 1000 m de profondeur). Il rassemble en un même lieu tous les types de minéralisation associés à une discordance connus de par le monde. Cette étude s'appuie sur l'analyse de plus de 1200 échantillons du halo d'altération qui entoure le gisement et sur l'utilisation des données d'exploration minière. L'objectif est double. Il s'agit d'une part de déterminer des guides sédimentologiques, pétrographiques, minéralogiques et géochimiques pour la prospection des corps minéralisés en zone profonde et d'autre part d'utiliser ces critères pour construire une représentation tridimensionnelle simplifiée (minéralisation et halo d'altération) permettant de préciser le modèle génétique de ce gisement profond. La localisation des différentes zones minéralisées dépend non seulement des phénomènes d'altération liés aux circulations hydrothermales contrôlées par la tectonique, mais aussi de la nature du remplissage sédimentaire et de son évolution diagénétique. L'architecture de la zone minéralisée de Shea Creek montre que les corps minéralisés sont localisés dans des structures en grabben remplies par des alternances de grès propres et de grès argileux souvent préservés de la compaction et de l'altération. La signature minéralogique et géochimique de ces grès suggère un apport provenant de l'érosion de paléo-altérites continentales (régolithe). La très forte concentration en défauts d'ir / Shea Creek is an unconformity-type uranium deposit located in the west part of Atabaska basin. It is related to an unconformity between a metamorphic basement and sedimentary rocks of fluvial origin, of paleoproterozoic age. Shea Creek's particularity is to be the deepest ore deposit ever known in the basin (between 680 m and 1000 m deep). It gathers all types of unconformity hosted mineralization known. More than 1200 samples, taken from halo alteration around the deposit, were analyzed and mining exploration data were used for this study. First, the aim was to determine the markers for prospection of mineral elements in deep area: sedimentological, petrographical, geochemical and mineralogical types. Then, it was to build a simple three-dimensional model (mineralization and alteration halo) using these criteria in order to precise the genetic pattern of this deep deposit. The location of mineralized areas depends on tectonic deformation, on sedimentary filling and diagenetic development. The morphology of Shea Creek’s ore deposit shows clearly that mineralization is located in the grabbens composed by clean sandstones and clay sandstones, often preserved from compaction and alteration phenomena. The mineralogical and geochemical signature of these clay sandstones suggests a contribution from the erosion of continental paleo-alterite (regolith). Beside, the great concentration of radiation induced defects suggests the presence in abundance of uranium in the grabbens from sedimentary state.

Depuis leur découverte au milieu des années quatre-vingt, les noyaux à halo n'ont cessé d'intriguer et de fasciner. Cette découverte a été rendue possible par le développement de faisceaux d'ions radioactifs au cours des années septante. Cette performance a ouvert le champ de l'exploration des propriétés des noyaux atomiques aux frontières de la stabilité.<p><p>Les noyaux à halo présentent une taille beaucoup plus grande que prévue par l'hypothèse communément adoptée du noyau sphérique et seraient constitués d'un coeur, qui a les propriétés d'un noyau normal, auquel un ou deux neutrons qui forment le halo seraient faiblement liés. Cette propriété bouleverse complètement l'image traditionnelle du noyau atomique, celle d'un mélange quasiment homogène de protons et de neutrons.<p><p>Les noyaux à halo ont tendance à facilement se dissocier lorsqu'ils entrent en collision avec un noyau cible. Leurs réactions de dissociation constituent donc un formidable outil expérimental pour étudier leurs propriétés. Cependant l'analyse de telles réactions nécessite une description précise du processus de collision. A cette fin, nous avons développé un nouveau modèle de réaction: l'approximation eikonale dynamique. Il s'agit d'une méthode purement quantique qui combine les avantages des approximations eikonale traditionnelle et semi-classique. Elle prend en compte aussi bien les effets dynamiques du mouvement interne du projectile que les interférences quantiques entre les trajectoires. Elle conduit à la résolution d'une équation de Schrödinger approchée similaire à celle de l'approximation semi-classique avec trajectoires rectilignes.<p><p>Nous appliquons l'approximation eikonale dynamique à l'étude de réactions impliquant trois noyaux à halo différents :le $^{11}$Be, le $^{19}$C et le $^{8}$B. Pour les trois systèmes étudiés, nous confrontons nos résultats théoriques avec les données expérimentales disponibles. Nous constatons un très bon accord tant sur l'allure que sur l'ordre de grandeur des différentes sections efficaces. Ceci est valable aussi bien pour les collisions sur cible lourde que sur cible légère. Les motifs d'interférence présents dans les distributions angulaires sont également bien reproduits par notre modèle, y compris pour la diffusion élastique.<p><p>Nous analysons la section efficace de dissociation expérimentale du $^{19}$C dans le but de déterminer la présence d'une résonance dans le spectre continu de ce noyau. Nous constatons que plusieurs options restent plausibles et que d'autres mesures sont nécessaires (sur cible légère, par exemple) pour confirmer nos hypothèses.<p><p>La dissociation coulombienne du $^{8}$B fait l'objet de nombreuses études expérimentales dans le but d'obtenir des informations sur la réaction inverse qu'est la capture radiative $^{7}$Be(p,$gamma$)$^{8}$B. En analysant cinq expériences pour lesquelles différentes observables ont été mesurées, nous examinons la validité des hypothèses qui permettent de faire un lien direct entre dissociation et capture radiative. Nous observons que l'extraction d'informations sur la capture radiative à partir de données de dissociation semble plus compliqué qu'initiallement prévu. Cependant les différentes mesures permettent de valider un modèle de structure du $^{8}$B qui peut servir au calcul de la section efficace de capture radiative.<p><p>L'approximation eikonale dynamique constitue donc un outil performant qui permet d'analyser toutes les observables liées à la dissociation élastique d'un noyau à halo sur une cible lourde ou légère à des énergies incidentes de quelques dizaines de MeV par nucléon. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

Beginning with his High Mass written in 1994, popular Swedish composer Sven-David Sandström modeled multiple compositions after famous canonical works using the same texts and/or instrumentation. Sandström wants to be compared to the greatest, specifically in how a twenty-first century composer responds to a text set , in the case of J.S. Bach's , over 250 years ago. His setting of Matthäuspassion (MP), which uses the same libretto as J.S. Bach, is his most extensive non-operatic work, one he considers his most significant, and likely his last work based on a preexisting model. This study 1) examines the influence of J.S. Bach's MP on Sandström's setting in the use of characters and chorales, 2) illustrates Sandström's compositional language in MP based on recent studies on his choral music, 3) describes his use of musical symbolism, and 4) discusses his religious and spiritual motivations behind the work, as well as his preferred uses in performance.

The Milky Way has undergone several mergers with other galaxies during its lifetime. The mergers have been identified via stellar debris in the Halo of the Milky Way. The practice of mapping these mergers is called galactic archaeology. To perform this archaeologic inspection, three stellar features must be mapped: chemistry, kinematics and age. Historically, the latter has been difficult to determine, but can today to high degree be determined through asteroseismology. Red giants are well fit for these analyses. In this thesis, the red giant HE1405-0822 is completely characterized, using spectroscopy, asteroseismology and orbit integration, to map its origin. HE1405-0822 is a CEMP-r/s enhanced star in a binary system. Spectroscopy and asteroseismology are used in concert, iteratively to get precise stellar parameters, abundances and age. Its kinematics are analyzed, e.g. in action and velocity space, to see if it belongs to any known kinematical substructures in the Halo. It is shown that the mass accretion that HE1405-0822 has undergone has given it a seemingly younger age than probable. The binary probably transfered C- and s-process rich matter, but how it gained its r-process enhancement is still unknown. It also does not seem like the star comes from a known merger event based on its kinematics, and could possibly be a heated thick disk star. / Vintergatan har genomgått flera sammanslagningar med andra galaxer under sin livstid. Dessa sammanslagningar har identifierats genom rester av stjärnor i Vintergatans Halo. Arbetssättet för att kartlägga dessa sammanslagningar kallas galaktisk arkeologi. För att kunna göra en arkeologisk undersökning krävs tre egenskaper hos de undersökta stjärnorna: kemi, kinematik och ålder. Historiskt sett har den sistnämnda varit svår att bestämma, men kan idag bestämmas med hög precision m.h.a. asteroseismologi. Röda jättar lämpar sig väl för dessa analyser. I denna uppsats undersöks den röda jätten HE1405-0822. Den kartläggs helt m.h.a. spektroskopi, asteroseismologi och bananalys. HE1405-0822 är en CEMP-r/s-förhöjd stjärna i ett binärt system. Spektroskopi och asteroseismologi används tillsammans, iterativt, för att få precisa stjärnparametrar, kemiskt innehåll och ålder. Dess kinematik analyseras, t.ex. i verkan- och hastighetsrummet, för att se om den tillhör någon känd kinematisk substruktur i Halon. Det visas att massöverföringen som HE1405-0822 genomgått har gett den en skenbart yngre ålder än vad som är troligt. Denna binära kompanjon har troligtvis övertfört C- och s-process-rikt material, men hur den fick sin mängd r-processämnen är fortfarande okänt. Det verkar inte som att stjärnan kommer från någon tidigare kartlagd sammanslagning baserat på dess kinematik, och skulle kunna vara en stjärna med upphettad kinematik från Vintergatans tjocka disk.

One-nucleon halo nuclei are exotic nuclei which can be seen as a core around which orbits a loosely-bound valence nucleon. They are usually studied through reactions such as elastic scattering and breakup. The ratio method has been developed as a tool to study one-neutron halo nuclei at high energies. It consists of the ratio of angular cross sections, breakup and elastic scattering, which removes most of the sensitivity to the reaction mechanism and to the reaction model. In the simple recoil excitation and breakup (REB) model, the ratio simplifies to a form factor dependent solely on the wave function of the projectile. By measuring this observable and comparing it to the REB form factor, i.e. in the ratio method, more detailed information on the structure of the halo could be obtained. For neutron-halo nuclei at high energy, the ratio observable obtained from accurate CDCC and DEA theoretical calculations follows its REB prediction. I study the extension of this method to lower energies of the reaction which could make the measurement appropriate to facilities such as SPIRAL2 (GANIL, Caen, France) and ReA12 at FRIB (Michigan State University) and to proton halos. This is done by comparing the REB form factor to dynamical calculations of the ratio. The reactions investigated are the reaction of 11Be, the archetypical one-neutron halo nucleus, on 12C, 40Ca and 208Pb targets at 20 MeV/nucleon and of 8B, the archetypical one-proton halo nucleus, on 12C, 58Ni and 208Pb targets at44 MeV/nucleon.For these reactions, the adiabatic assumption is no longer valid due to the effect of the Coulomb interaction. This effect is mainly visible at forward angle for 11Be and is aggravated for 8B by the fact that the halo is charged. The ratio works less well than for neutron-halos at intermediate and high energies. Nevertheless, the ratio is shown to be very sensitive to the orbital angular momentum l0 in which the halo is bound and its binding energy E0, i.e. the single-particle structure of the projectile. Variations of l0 and E0 induce visible changes in shape and in magnitude (up to several orders) of the ratio. Also, the agreement of the ratio with its REB prediction is best when the projectile is loosely-bound and for low l0, i.e. for s and p waves. The validity of the method is not affected by the use of energy ranges—or bins— in the projectile continuum. These tend to increase the cross section without changing the agreement of the ratio with its REB prediction. The applicability of the method is finally explored at high energy for proton-rich nuclei 17F, 25Al and 27P. I show that the ratio method works the latter since this nucleus is bound by a mere 0.870 MeV in the s-wave. For the other nuclei, although the agreement of the ratio with its REB prediction is less good than for neutron-halo nuclei at high energy, it still provides estimates of nuclear-structure features, such as l0 and E0 and could be applied in what can be called an approximate application of the ratio method. Heavy nuclei exhibit a neutron skin, i.e. a thin layer around the nucleus where only neutrons are found. The thickness of the skin is highly correlated with the slope of the symmetry energy. The process of coherent neutral-pion photoproduction is used to extract the nuclear density and hence the neutron-skin thickness of heavy nuclei. In order to analyse recent data on the photoproduction on 12C, 40,48Ca, 116, 120, 124Sn and 208Pb, I build a reaction code. My model uses the formalism of Kerman, McManus and Thaler (KMT) which allows to build the photoproduction matrix on a nucleus from the ones describing the elementary process on a single nucleon. Within the impulse approximation, the photoproduction is seen as the coherent sum of the photoproduction on each of the nucleons. In the plane wave impulse approximation (PWIA), no rescattering of the pion is considered after its production and the cross section is directly proportional to the Fourier transform of the density. Such process is taken into account at the distorted wave impulse approximation (DWIA) by considering a potential simulating the pion-nucleus interaction and built from the KMT formalism.The agreement of my model with the data is good, especially for 208Pb. The distortion has a significant impact on the photoproduction process. The sensitivity of the process to the density of the target is analysed by performing the calculations with several different densities calculated in different structure models. The distortion has the effect of deteriorating this sensitivity. In the particular case of a 208Pb target, the impact of variations of the neutron-skin thickness of around 0.1 fm on the photoproduction cross section is ten times smaller than the size of the error bars on the experimental data. These results, although less dramatic, hold for the tin targets, for which preliminary data exists. In the light of these results, the coherent neutral-pion photoproduction process does not seem to be suited in the study of the neutron-skin thickness. This conclusion goes in contrast to the results of recent measurements on 208Pb, for which the method was shown to be sensitive to fine details of the density. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished