Relevant bibliographies by topics / Magnetic inhomogeneities

Academic literature on the topic 'Magnetic inhomogeneities'

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Published: 14 March 2023

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Journal articles on the topic "Magnetic inhomogeneities"

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Rudnick, Lawrence. "Manifestations of Magnetic Field Inhomogeneities." Journal of Astrophysics and Astronomy 32, no. 4 (December 2011): 549–55. http://dx.doi.org/10.1007/s12036-011-9113-5.

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Gogola, D., A. Krafčík, O. Štrbák, and I. Frollo. "Magnetic Resonance Imaging of Surgical Implants Made from Weak Magnetic Materials." Measurement Science Review 13, no. 4 (August 1, 2013): 165–68. http://dx.doi.org/10.2478/msr-2013-0026.

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Materials with high magnetic susceptibility cause local inhomogeneities in the main field of the magnetic resonance (MR) tomograph. These inhomogeneities lead to loss of phase coherence, and thus to a rapid loss of signal in the image. In our research we investigated inhomogeneous field of magnetic implants such as magnetic fibers, designed for inner suture during surgery. The magnetic field inhomogeneities were studied at low magnetic planar phantom, which was made from four thin strips of magnetic tape, arranged grid-wise. We optimized the properties of imaging sequences with the aim to find the best setup for magnetic fiber visualization. These fibers can be potentially exploited in surgery for internal stitches. Stitches can be visualized by the magnetic resonance imaging (MRI) method after surgery. This study shows that the imaging of magnetic implants is possible by using the low field MRI systems, without the use of complicated post processing techniques (e.g., IDEAL).
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Wu, Huiyan, Kerong Zhu, Guoyong Xu, and Hu Wang. "Magnetic inhomogeneities in electron-doped manganites ()." Physica B: Condensed Matter 407, no. 4 (February 2012): 770–73. http://dx.doi.org/10.1016/j.physb.2011.12.022.

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Gaunt, Paul. "Magnetic coercivity." Canadian Journal of Physics 65, no. 10 (October 1, 1987): 1194–99. http://dx.doi.org/10.1139/p87-195.

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The theory of magnetic hardening and its impact on the design of permanent magnets is presented. The statistical theory of domain-wall pinning by sample inhomogeneities is outlined, and its relevance to the latest generation of permanent magnets is discussed.
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Shcherbakov, A. G., M. J. Fernandez-Figueroa, F. Martin-Parra, E. De Castro, and M. Cornide. "The HeI λ10830 Å Observations of Two Rs Cvn Systems ζ and λ And." Symposium - International Astronomical Union 157 (1993): 167–69. http://dx.doi.org/10.1017/s0074180900174054.

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Magnetically active late-type stars have inhomogeneities on their surfaces that cause various observable effects in the spectral lines and light curves. Such inhomogeneities are magnetic starspots, plages etc. in active regions on the photospheric and chromospheric level. The variations of the spectral lines and light curves originating in these inhomogeneities undergo modulations following stellar rotation.
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Makarov, P., V. Ustyugov, and V. Scheglov. "Modelling of electromagnetic wave propagation in magnetically inhomogeneous media." Proceedings of the Komi Science Centre of the Ural Division of the Russian Academy of Sciences, no. 5 (December 20, 2022): 100–105. http://dx.doi.org/10.19110/1994-5655-2022-5-100-105.

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This paper discusses the FDTD-algorithm for modeling electromagnetic wave propagation in randomly inhomogeneous magnetic media. We present the modeling results of square wave signals propagation in time-independent nanocomposite films with magnetic inhomogeneities of two types: with a random distribution of inhomogeneities throughout the film thickness and the “close packing” in the center.
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Ekomasov, E. G., and R. R. Murtazin. "Modeling of the nucleation of magnetic inhomogeneities in ferromagnets with inhomogeneities material parameters." Letters on Materials 2, no. 1 (2012): 9–12. http://dx.doi.org/10.22226/2410-3535-2012-1-9-12.

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Michaud, G. "Particle transport and surface abundance inhomogeneities." Symposium - International Astronomical Union 176 (1996): 321–28. http://dx.doi.org/10.1017/s0074180900083339.

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The various mechanisms leading to the appearance of horizontal inhomogeneities at the surface of ApBp stars are critically reviewed. The effect of magnetic fields is essential but is it more to control locally, on the surface, the appearance of anomalies that are caused by the vertical transport of particles, or is it to create directly the horizontal inhomogeneities by horizontal transport? The time scales for horizontal and vertical transport will be discussed in this context.The processes discussed include: a) ambipolar diffusion of protons and hydrogen in the presence of magnetic fields; b) the guiding of diffusion by magnetic fields; c) the horizontal component of radiative accelerations; d) mass loss; e) light induced drift.
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Seppenwoolde, Jan-Henry, Mathilda van Zijtveld, and Chris J. G. Bakker. "Spectral characterization of local magnetic field inhomogeneities." Physics in Medicine and Biology 50, no. 2 (January 7, 2005): 361–72. http://dx.doi.org/10.1088/0031-9155/50/2/013.

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Ling, C. D., E. Granado, J. J. Neumeier, J. W. Lynn, and D. N. Argyriou. "Magnetic inhomogeneities in electron-doped Ca1−xLaxMnO3." Journal of Magnetism and Magnetic Materials 272-276 (May 2004): 246–48. http://dx.doi.org/10.1016/j.jmmm.2003.11.102.

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Dissertations / Theses on the topic "Magnetic inhomogeneities"

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Pasquato, Ester. "Effects of stellar surface inhomogeneities on astrometric accuracy." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209872.

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Surface brightness asymmetries are a very common feature of stars. Among other effects they cause a difference between the projected centre of mass and the photocentre. The evolution of those surface features makes this difference time-dependent. In some cases the displacement can be a non-negligible fraction of the star radius R, and if R>1 AU, of the parallax. We investigate the impact of surface brightness asymmetries on the Gaia astrometric solution and on the data processing flow. In particular we derive analytical expressions for the change in the derived astrometric parameters for a single-star, with respect to the parameters for a uniformly-bright star, as a function of the characteristics of the surface brightness asymmetries. These predictions are confirmed by the results of the processing of simulated astrometric Gaia data where a photocentre motion caused by surface brightness asymmetries has been added using a Gaussian Markovian model.

In the case of a red supergiant star, the average photocentre shift is about 0.1 AU. Such a photocentric noise translates in a 10% inaccuracy on the parallax (independently of the distance), which becomes larger than the statistical error on the parallax derived from the data reduction for stars that are up to about 4 kpc away. For the most nearby stars, we derive an inaccuracy on the parallax that can be 10 times its statistical error. Finally we estimate that up to about 4000 stars among red supergiants and bright giants may have astrometric parameters that are inaccurate at levels bigger than expected because of the surface brightness asymmetries. In the determination of this number, a crucial role is played by the Gaia observable magnitude range. The fact that Gaia will not observe stars brighter than 5.6 in the Gaia G band means that the closest stars will not be observed. Yet, the impact of the surface brightness asymmetries is proportional to their angular size, meaning that the stars whose astrometric accuracy would be most affected are not observed.

Various non-Gaussian spot models (as applicable in the case of magnetic spots) have been implemented and analytical predictions for the effects of such magnetic spots are computed for the most representative classes of magnetic stars.

Another effect of the presence of surface brightness asymmetries is their impact on Gaia data processing flow. The quality of the fit of the data is evaluated with the F2 parameter that is a transformation of χ2 such that it has a unit normal distribution when the model is adequate and it is independent of the number of measurements. If the goodness-of-fit F2 of the single-star solution is not good enough (F2>3), a chain of solution of growing complexity is tried until a satisfactory one (with F2<3) is obtained. If no good solution is found, a so-called stochastic solution is computed where a "cosmic" error is added to the data in order to obtain a single-star solution with F2=0. We show that the photocentre noise induces an increase in the goodness-of-fit parameter, causing this chain of solutions to be entered. Depending on the characteristics of the photocentre noise, a variable fraction of the stars in our simulations end up with a non-single-star solution. Yet, we show that these (orbital) solutions are not acceptable because non-significant or non-physical. Finally, an important fraction of stars is assigned a stochastic solution with a cosmic noise matching well the photocentric noise.

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Les asymétries de brillance de surface sont une caractéristique commune des étoiles. Parmi d'autres effets, elles provoquent une différence entre la projection du centre de masse et le photocentre. L'évolution de ces structures de surface rend cette différence variable avec le temps. Dans certains cas, le déplacement du photocentre peut être une fraction non négligeable du rayon de l'étoile R et, si R>1 UA, de la parallaxe. Nous examinons l'impact des asymétries de brillance de surface sur la solution astrométrique de Gaia et sur le processus de traitement des données. En particulier nous dérivons des expressions analytiques pour le changement des paramètres astrométriques déerivées pour une étoile simple, par rapport aux paramètres pour une étoile uniformément lumineuse, en fonction des caractéristiques des asymétries de brillance de surface. Ces prévisions sont confirmées par les résultats de simulations du traitement des données astrométriques de Gaia, auxquelles des mouvements du photocentre causés par des asymétries de brillance de surface ont été ajoutés en utilisant un modèle gaussien markovien.

Dans le cas d'une étoile super-géante rouge, le décalage moyen du photocentre est d'environ 0.1 UA. Un bruit photocentrique de cette amplitude se traduit dans une imprécision de 10% sur la parallaxe (indépendamment de la distance), qui peut devenir plus grande que l'erreur statistique sur la parallaxe déerivée par la réduction des données, pour les étoiles plus proches d'environ 4 kpc. Pour les étoiles les plus proches, nous évaluons une imprécision sur la parallaxe qui peut être 10 fois leur erreur statistique. Finalement, nous estimons que jusqu'à environ 4000 étoiles parmi les super-géantes rouges et géantes brillantes peuvent avoir des paramètres astrométriques inexactes à des niveaux plus grands que prévu en raison des asymétries de brillance de surface. Dans la détermination de ce nombre, la gamme de magnitudes observables par Gaia joue un rôle crucial. Le fait que Gaia n'observera pas les étoiles plus brillantes que 5.6 mag (en bande Gaia) signifie que les étoiles les plus proches ne seront pas observées. Pourtant, l'impact des asymétries de brillance de surface est proportionnel à leur taille angulaire, ce qui signifie que les étoiles dont la précision astrométrique seraient la plus affecté ne seront pas observées.

Différents modèles de taches ont été réalisés et des prédictions analytiques pour les effets de ces taches magnétiques sont calculés pour les classes les plus représentatives des étoiles magnétiques.

Un autre effet de la présence des asymétries de brillance de surface est leur impact sur le traitement des données de Gaia. La qualité de l'ajustement des données est évaluée avec le paramètre F2 qui est une transformation de χ2 telle qu'il ait une distribution normale lorsque le modèle est adéquat. Si la qualité de l'ajustement F2 de la solution étoile-simple n'est pas acceptable (F2>3), une chaîne de solutions de complexité croissante est essayée jusqu'à ce qu'une solution satisfaisante (avec F2<3) soit obtenue. Si aucune solution satisfaisante n'est trouvée, une solution dite stochastique est calculée où une erreur "cosmique" est ajoutée aux données afin d'obtenir une solution étoile-simple avec F2=0. Nous montrons que le bruit du photocentre induit une augmentation de F2, ce qui provoque l'activation de cette chaîne de solutions. Selon les caractéristiques du bruit du photocentre, une solution étoile-non-simple est obtenue pour une fraction variable des étoiles dans nos simulations. Nous montrons que ces solutions (orbitales) ainsi obtenues ne sont pas acceptables car non significatives ou non-physiques. Enfin, une fraction importante d'étoiles se voient attribuer une solution stochastique avec un bruit cosmique correspondant au bruit photocentrique.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Assländer, Jakob [Verfasser]. "Static Field Inhomogeneities in Magnetic Resonance Encephalography: Effects and Mitigation / Jakob Assländer." München : Verlag Dr. Hut, 2014. http://d-nb.info/1063221269/34.

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Baumann, Christoph. "Magnetic and structural inhomogeneities in single layered manganites La1-xSr1+xMnO4 : hyperfine field investigations /." Berlin : Mensch-und-Buch-Verl, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014182273&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Assländer, Jakob [Verfasser], and Jürgen [Akademischer Betreuer] Hennig. "Static field inhomogeneities in magnetic resonance encephalography : : effects and mitigation = Statische Magnetfeldinhomogenitäten in der Magnetresonanzencephalographie : Effekte und Mitigation." Freiburg : Universität, 2014. http://d-nb.info/1123481458/34.

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Körzdörfer, Gregor [Verfasser], Bernhard [Akademischer Betreuer] Hensel, and Bernhard [Gutachter] Hensel. "Analysis and Mitigation of the Effect of Magnetic Field Inhomogeneities and Undersampling Artifacts on Magnetic Resonance Fingerprinting / Gregor Körzdörfer ; Gutachter: Bernhard Hensel ; Betreuer: Bernhard Hensel." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/1211822125/34.

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Reich, Jan Christoph [Verfasser], and G. [Akademischer Betreuer] Drexlin. "Magnetic Field Inhomogeneities and Their Influence on Transmission and Background at the KATRIN Main Spectrometer / Jan Christoph Reich. Betreuer: G. Drexlin." Karlsruhe : KIT-Bibliothek, 2013. http://d-nb.info/1031709037/34.

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Benitez, Mendieta Jessica. "An efficient and semiautomatic segmentation method for 3D surface reconstruction of the lumbar spine from Magnetic Resonance Imaging (MRI)." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/101274/1/Jessica_Benitez%20Mendieta_Thesis.pdf.

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A new semiautomatic technique for the segmentation and reconstruction of 3D vertebral anatomy from MRI is presented where five cadaveric human lumbar spines and one ovine spine were used. The MR images were subjected to contrast enhancement, anisotropic diffusion filtering, and thresholding was selected as the preferable segmentation technique to create 3D surfaces from the MRI datasets. The reconstructions were manually cleaned using commercial software. The resulting reconstructed surface included discrete vertebral bodies with distinct separation between the spinous processes. CT reconstructions were used to assess the accuracy of the reconstructed spinal anatomy from MRI.
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Splitthoff, Daniel Nicolas [Verfasser], and Jürgen [Akademischer Betreuer] Hennig. "SENSE shimming (SSH) : : fast detection of B0 field inhomogeneities in magnetic resonance imaging = SENSE Shimming (SSH) : schnelle Detektion von B0 Feldinhomogenitäten in der Magnet-Resonanz-Bildgebung." Freiburg : Universität, 2012. http://d-nb.info/1123467404/34.

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De, Biasi Federico. "Matrix-Assisted NMR." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3424861.

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During the last decades, the interest of chemistry toward increasingly sophisticated processes has grown exponentially. As a consequence, the evolution of the systems under investigation has been necessarily paired with the development of modern methodologies capable of handling the enormous amount of data stemming from samples of great complexity. Among the many examples in the literature, one of the biggest ongoing challenges is the analysis of mixtures, from reaction crude extracts to biological fluids like blood and urine. Indeed, chromatography has been - and still remains - one of the primary methods adopted to reduce the complexity of a multi-analyte system. Nonetheless, one intrinsic problem of the chromatographic approach is its inability to identify unknown molecules, and hyphenated techniques (mostly based on mass spectroscopy) have been developed just to overcome this stumbling block. On the other hand, Nuclear Magnetic Resonance (NMR) spectroscopy is one of the most powerful techniques for the investigation of organic compounds. NMR exploits an intrinsic property exhibited by some atomic nuclei -- the spin -- to acquire chemical and structural information through well-established experimental protocols, known as pulse sequences. In particular, solution-state NMR can boast a vast ensemble of procedures aimed at collecting detailed data about through bond connectivities (COSY, TOCSY, HSQC,...) or through space proximities (NOESY, ROESY,...). All these information are nothing less than fundamental for the structure determination of unknown compounds. Even tough this makes NMR spectroscopy largely appealing, the acquisition of such extensive information ultimately translates into detecting many signals at once, so that spectra interpretation can become a very challenging task. This is especially true when observing 1H resonances, which display a small dispersion in the frequency domain (about 12 ppm) and spectral crowding becomes consequently a serious problem. Not surprisingly, the situation becomes almost unmanageable when NMR is applied to the assay of mixtures, where the superposition of signals stemming from different species is virtually assured. Certainly, multidimensional NMR techniques can be useful for the interpretation of crowded single-molecule spectra, but they rapidly loose all their advantages as the number of components in the sample increases. As for chromatography, the advent of hybrid techniques like LC-NMR, where LC stands for Liquid Chromatography, has partly circumvented the aforementioned difficulties, yet at the cost of an expensive and dedicated instrumentation. In the context of mixture analysis, matrix-assisted NMR methodologies stand as an alternative to the various hyphenated techniques. They rely on the combination of NMR spectroscopy and an external agent added to the sample, which can be either a molecular or macromolecular species, or even a mesoscopic matrix. The aim of such matrices is to differentiate the signals of the various components, favouring their detection and characterisation. The present work is divided into three independent parts. The first two are dedicated to different subjects of matrix-assisted NMR. In particular, Part I is aimed at the understanding of the physical phenomena underlying signal broadening when a solid, stationary phase is used in Matrix-Assisted Diffusometry (MAD) NMR measurements. Part II focuses on nanoparticle-assisted NMR chemosensing, a technique where monolayer-protected gold nanoparticles are exploited to transfer magnetization to selected classes of analytes by means of the Nuclear Overhauser Effect. In this second part, different nanoparticle-assisted methodologies are presented and analysed, alongside with some strategies aimed at the enhancement of the sensitivity. Part III concerns the complete 1H-NMR characterisation of the atomically precise Au38(SBut)24 gold nanocluster, which can be considered as a prototypical nanoparticle. The Au38 core features four different symmetry-unique and equally populated binding sites for the grafting of the ligands that constitute the coating monolayer. Each binding site shows a distinct pattern of resonances, so that the overall 1H-NMR spectrum of the cluster is the result of the superposition of four independent subspectra. In this case, the full characterisation of the spectrum has been achieved through a combined NMR-MD (Molecular Dynamics) analysis.
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Lemarchand, Nadège. "Impacts of cosmic inhomogeneities on the CMB : primordial perturbations in two-field bouncing cosmologies and cosmic magnetism in late-time structures Secondary CMB anisotropies from magnetized haloes I. Power spectra of the Faraday rotation angle and conversion rate." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS510.

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Le Fond Diffus Cosmologique (FDC) est une sonde cosmologique clé mettant des contraintes étroites sur le modèle CDM de l’Univers. Emis 380000 ans après le big bang, il montre de petites anisotropies en température et en polarisation qui tracent les inhomogénéités cosmiques à différentes époques de l’Univers. D’une part, les anisotropies primaires donnent accès à l’inflation durant laquelle les perturbations primordiales sont générées. D’autre part, les anisotropies secondaires tracent les inhomogénéités dans l’Univers récent, qui ont évolué en grandes structures sous l’action de la gravité, à partir des inhomogénéités primordiales. Ainsi les anisotropies du CMB sont une sonde puissante à la fois de l’origine des inhomogénéités dans l’Univers très jeune, et de leur état évolué dans l’Univers récent. Cette thèse porte sur deux aspects des inhomogénéités: d’abord leur production dans une extension du scénario inflationnaire, puis la prédiction de l’impact des champs magnétiques des grandes structures sur les anisotropies secondaires polarisées du FDC.Malgré ses succès, l’inflation ne résout pas le problème de la singularité initiale du big bang, où la gravité pourrait être quantique. En Cosmologie Quantique à Boucles (CQB), cette singularité est remplacée par un rebond quantique. La CQB à un champ avec potentiel quadratique a déjà été étudiée et prédit une phase d’inflation suivant le rebond. Les perturbations primordiales ne sont plus seulement produites pendant l’inflation, mais aussi pendant le rebond et la contraction le précédant. Ici, j’ai considéré une extension à deux champs de la CQB avec un champ massif comme inflaton, et un champ sans masse servant d’horloge interne. J’ai d’abord étudié l’évolution globale de l’Univers de manière analytique et numérique, montrant que loin dans la contraction, le champ massif domine le contenu énergétique. J’ai aussi vérifié que l’inflation reste probable, malgré la présence du champ sans masse. Puis, j’ai examiné la production de perturbations: contrairement au cas à un champ, en plus de la composante adiabatique standard, elles sont ici décrites par une composante isocourbe, caractéristique des modèles multi-champs et pour laquelle Planck a mis des limites supérieures. Loin dans la contraction, ces deux composantes sont hautement couplées. J’ai montré comment fixer leurs conditions initiales en utilisant des variables combinant les deux types de perturbations, rendant le couplage sous-dominant. Il reste maintenant à les propager à travers le rebond jusqu’à la fin de l’inflation pour obtenir leurs spectres de puissance (croisé), à comparer ensuite aux contraintes observationnelles.Depuis son émission, le FDC a voyagé à travers les grandes structures avant de nous atteindre. Son interaction avec les structures engendre des anisotropies secondaires, comme celles dues à l’effet SZ dans les amas. Des plasmas magnétisés ont été observés dans les galaxies et les grandes structures. Cela devrait engendrer de la Rotation Faraday (RF) de la polarisation linéaire primordiale, transformant des modes E en B, et de la Conversion Faraday (CF) de la polarisation linéaire en circulaire. J’ai revisité ces sources d’anisotropies en calculant les spectres de puissance angulaires de l’angle de RF et du taux de CF par les grandes structures. J’ai utilisé le modèle de halo en me focalisant sur l’impact des projections des champs magnétiques. Les spectres piquent à des multipoles 104 et sont proportionnels à 83, en supposant un champ magnétique indépendant de la masse du halo. Cette dépendance est cependant dégénérée avec celle qui existe entre les champs magnétiques et la masse des halos. Puis, je détaille le calcul des spectres de puissance angulaires totaux des anisotropies polarisées, à partir de ceux de la RF et de la CF. Enfin, je montre comment reconstruire les champs de RF et de CF à partir du FDC en adaptant les estimateurs développés pour la reconstruction du lentillage gravitationnel
The Cosmic Microwave Background (CMB) is a key cosmological probe, that sets tight constraints on the CDM model of the Universe. Released 380000 years after the big bang, it exhibits tiny anisotropies in temperature and polarisation which trace the cosmic inhomogeneities at different epochs of the Universe. On the one hand, primary anisotropies give access to inflation, during which the primordial perturbations are generated. On the other hand, secondary anisotropies trace inhomogeneities in the recent Universe, which have evolved into large scale structures through gravity, starting from the primordial ones. Hence CMB anisotropies are a powerful probe of both the origin of inhomogeneities in the very early Universe, and their evolved state in the late-time Universe. This thesis deals with two aspects of inhomogeneities by first considering their production in an extension of the inflationary scenario, and second by predicting the impact of magnetic fields in large scale structures on the secondary CMB polarised anisotropies.Despite its successes, inflation does not solve the initial big bang singularity issue, where gravity might need to be quantised. In Loop Quantum Cosmology (LQC), this singularity is replaced by a quantum bounce. Single field LQC with quadratic potential has already been studied and predicts an inflation phase following the bounce. Then, primordial inhomogeneities are not only produced during inflation, but also during the bounce and the contraction preceding it. Here, I considered a multifield extension of LQC with two fields: a massive one as being the inflaton, and a massless one used as an internal clock. I first studied the background evolution of the Universe both analytically and numerically. I showed that far in the contraction, the massive field dominates the energy budget. I have also checked that inflation remains likely to happen, despite the presence of the massless field. Secondly, I investigated how perturbations are produced. Unlike the one-field case, they are now described by an isocurvature component in addition to the standard adiabatic one, the former being characteristic of multifield models, for which Planck has put upper limits. In the remote past of the contraction, these two kinds of perturbations are highly coupled. I showed how to set their initial conditions by using appropriate variables mixing both kinds of perturbations, making the coupling subdominant. These perturbations remain to be propagated through the bounce down to the end of inflation to get their primordial (cross)spectra, to be subsequently compared to observational constraints.Since its released, the CMB traveled through large scale structures before reaching us. This leads to secondary anisotropies by its interaction with these structures, like e.g. gravitational deflection or the SZ effect in clusters. Magnetic fields have been observed in galaxies and larger structures. Since these structures are also filled with free electrons, this should lead to the Faraday Rotation (FR) effect which rotates the primordial linear polarisation, turning E into B modes, and to the Faraday Conversion (FC) effect which converts linear into circular polarisation. I revisited these sources of secondary anisotropies by computing the angular power spectra of the FR angle and the FC rate by large-scale structures. I used the halo model paying special attention to the impact of magnetic field projections. I found angular power spectra peaking at multipoles 104. Assuming a mass-independent magnetic field, the angular power spectra scale with the amplitude of matter perturbations as 83. This scaling is however degenerated with the one of the magnetic field with halos’ mass. I finally detail how to compute the full angular power spectra of polarised anisotropies, starting from the FR and FC power spectra. I also show how to reconstruct the FR and FC fields from the CMB adapting the estimators developed for lensing reconstruction
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Books on the topic "Magnetic inhomogeneities"

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Kim, Jae Koul. Static field inhomogeneities in magnetic resonance imaging. 1995.

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Book chapters on the topic "Magnetic inhomogeneities"

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Ryutova, Margarita. "Effects of Flux Tube Inhomogeneities and Weak Nonlinearity." In Physics of Magnetic Flux Tubes, 75–105. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-96361-7_4.

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Ryutova, Margarita. "Effects of Flux Tube Inhomogeneities and Weak Nonlinearity." In Physics of Magnetic Flux Tubes, 69–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-45243-1_4.

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Maceroni, C., A. Bianchini, M. Rodonó, F. van't Veer, and R. Vio. "Statistics of magnetic cycles in late-type single and close binary stars." In Surface Inhomogeneities on Late-Type Stars, 303–6. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/3-540-55310-x_177.

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Khokhlova, V. L. "Study of Inhomogeneities on the Surface of Magnetic CP Stars." In Upper Main Sequence Stars with Anomalous Abundances, 125–34. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4714-6_18.

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Hubrig, S., and G. Mathys. "Mass Loss, Magnetic Field and Chemical Inhomogeneities in the He-Weak Star HD 21699." In Pulsation, Rotation and Mass Loss in Early-Type Stars, 167–68. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1030-3_44.

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Chikumoto, Noriko, Kimiyasu Furusawa, and Masato Murakami. "Magneto-Optical Studies of Chemical Inhomogeneities in Bi2212 Single Crystals." In Magneto-Optical Imaging, 119–24. Dordrecht: Springer Netherlands, 2004. http://dx.doi.org/10.1007/978-94-007-1007-8_15.

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Bardzokas, Demosthenis I., Michael L. Filshtinsky, and Leonid A. Filshtinsky. "Scattering of a Shear Wave by Cylindrical Inhomogeneities in Piezoceramic Media of Various Configurations (Antiplane Deformation)." In Mathematical Methods in Electro-Magneto-Elasticity, 181–228. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/3-540-71031-0_5.

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Nieto-Castanon, Alfonso. "FMRI minimal preprocessing pipeline." In Handbook of functional connectivity Magnetic Resonance Imaging methods in CONN, 3–16. Hilbert Press, 2020. http://dx.doi.org/10.56441/hilbertpress.2207.6599.

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This chapter describes standard and advanced preprocessing steps in fcMRI. These steps are aimed at correcting or minimizing the influence of well-known factors affecting the quality of functional and anatomical MRI data, including effects arising from subject motion within the scanner, temporal and spatial image distortions due to the sequential nature of the scanning acquisition protocol, and inhomogeneities in the scanner magnetic field, as well as anatomical differences among subjects.
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Sutton, Bradley P., and Fan Lam. "Imaging in the Presence of Magnetic Field Inhomogeneities." In Advances in Magnetic Resonance Technology and Applications, 327–54. Elsevier, 2022. http://dx.doi.org/10.1016/b978-0-12-822726-8.00023-3.

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Cheryauka, Arvidas, Michael S. Zhdanov, and Motoyuki Sato. "Chapter 5 Nonlinear approximations for electromagnetic scattering from electrical and magnetic inhomogeneities." In Methods in Geochemistry and Geophysics, 65–83. Elsevier, 2002. http://dx.doi.org/10.1016/s0076-6895(02)80087-7.

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Conference papers on the topic "Magnetic inhomogeneities"

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Noterdaeme, Olivier, and Michael Brady. "Correction of inhomogeneities in Magnetic Resonance Images." In 2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 2008. http://dx.doi.org/10.1109/iembs.2008.4649637.

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Krause, H., and J. Engemann. "Measurement of local material inhomogeneities in magnetic garnet films." In International Conference on Magnetics. IEEE, 1990. http://dx.doi.org/10.1109/intmag.1990.734959.

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BURGY, J., M. MAYR, V. MARTIN-MAYOR, A. MOREO, and E. DAGOTTO. "COLOSSAL EFFECTS IN TRANSITION METAL OXIDES CAUSED BY INTRINSIC INHOMOGENEITIES." In Physical Phenomena at High Magnetic Fields - IV. WORLD SCIENTIFIC, 2002. http://dx.doi.org/10.1142/9789812777805_0102.

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Liebgott, Florian, Christian Wurslin, and Bin Yang. "Segmentation of magnetic resonance images in presence of severe intensity inhomogeneities." In ICASSP 2013 - 2013 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). IEEE, 2013. http://dx.doi.org/10.1109/icassp.2013.6637802.

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Baym, Gordon, and Jen-Chieh Peng. "Evolution of Primordial Neutrino Helicities in Cosmic Magnetic Fields and Gravitational Inhomogeneities." In Proceedings of the 24th International Spin Symposium (SPIN2021). Journal of the Physical Society of Japan, 2022. http://dx.doi.org/10.7566/jpscp.37.020703.

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Поляков, Petr Polyakov, Акимов, and M. Akimov. "The distortion of the domain structure in the presence of a local magnetic defect in the film materials with a high anisotropy." In XXIV International Conference. Москва: Infra-m, 2016. http://dx.doi.org/10.12737/23178.

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The theory of magnetic domain of magnetic ordering in the film material, the presence of magnetic inhomogeneities caused by point defects of the dipole type, taking into account how changes in magnetostatic energy, and changes in the anisotropy energy of a domain wall curved. The analysis of the influence of the parameters determining the change in the energy of the magnetostatic interaction domain structure and the change in the anisotropy energy of a domain wall in the curved shape and the bending of the domain boundary.
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CORDERO, F., A. PAOLONE, C. CASTELLANO, and R. CANTELLI. "ANELASTIC MEASUREMENTS OF THE DYNAMICS OF LATTICE, CHARGE AND MAGNETIC INHOMOGENEITIES IN CUPRATES AND MANGANITES." In Proceedings of the Workshop. WORLD SCIENTIFIC, 2003. http://dx.doi.org/10.1142/9789812705112_0016.

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Chernigovskaya, M. A., B. G. Shpynev, and D. S. Khabituev. "Studying Longitudinal Inhomogeneities of the Ionospheric and Geomagnetic Disturbances in the Northern Hemisphere during Magnetic Storms." In 2019 Russian Open Conference on Radio Wave Propagation (RWP). IEEE, 2019. http://dx.doi.org/10.1109/rwp.2019.8810350.

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Granado, E., P. G. Pagliuso, J. A. Sanjurjo, C. Rettori, S. B. Oseroff, M. T. Causa, A. Butera, et al. "EFFECT OF INHOMOGENEITIES IN THE MAGNETIC PROPERTIES OF R1-xAxMnO3 (R = La,Pr; A = Ca, Sr)." In Proceedings of the Fifth International Workshop on Non-Crystalline Solids. WORLD SCIENTIFIC, 1998. http://dx.doi.org/10.1142/9789814447225_0015.

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Rousselet-Perraut, Karine, Chantal Stehle, Thierry Lanz, Thomas Boudoyen, Slobodan Jankov, Farrokh Vakili, Martin Kilbinger, Jean-Baptiste Lebouquin, and Oleg Kochukhov. "Mapping abundance inhomogeneities and magnetic fields of chemically peculiar (CP) stars with optical aperture synthesis arrays." In Astronomical Telescopes and Instrumentation, edited by Wesley A. Traub. SPIE, 2003. http://dx.doi.org/10.1117/12.458590.

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Reports on the topic "Magnetic inhomogeneities"

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Ryutova, M., M. Kaisig, and T. Tajima. Propagation of magnetoacoustic waves in the solar atmosphere with random inhomogeneities of density and magnetic fields. Office of Scientific and Technical Information (OSTI), August 1990. http://dx.doi.org/10.2172/6637341.

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