Dissertations / Theses: 'Electric Dipole Moment of the electron'

1

Condylis, Paul Constantine. "Measuring the electron electric dipole moment using supersonic YbF." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429391.

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2

Ashworth, Henry. "Towards an improved measurement of the electron electric dipole moment." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501120.

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3

Hudson, Jonathan James. "Measuring the electric dipole moment of the electron with YbF molecules." Thesis, University of Sussex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392800.

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4

Smallman, Ian Joseph. "A new measurement of the electron electric dipole moment using ytterbium fluoride." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/12872.

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This thesis describes a new measurement of the electron electric dipole moment (eEDM, de) made using a pulsed beam of ytterbium fluoride (YbF) molecules. YbF molecules are used as they greatly enhance the eEDM interaction with an applied electric field. In addition they suppress interactions with magnetic fields in the plane perpendicular to the applied electric field. This is hugely beneficial for suppressing the systematic effect that limited previous atomic eEDM searches. We measure the eEDM by performing a type of separated oscillating field interferometry, wherein the direction of applied electric and magnetic fields are reversed in between pulses of the molecular beam. From a dataset of 6194 individual eEDM measurements we find de = (-2.4 ± 5.7stat ± 1.5syst) x 10[superscript -28] e cm. This result is consistent with zero, so we set a new upper limit of |de| < 10.6 x 10[superscript -28] e cm at the 90% confidence level. A complete analysis of the dataset is given, with a thorough account of all the supplementary tests that were performed to check for systematic error. After publishing this world leading result we proceeded to upgrade the experiment to improve eEDM sensitivity and reduce certain systematic effects. This involved improving the rf polarisation along the parallel plate transmission line, shortening the rf pulse length and improving the magnetic shielding. A detailed discussion of the development and testing of the upgrades is given, including new measurements of the systematic uncertainties which will limit our next eEDM measurement.

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5

Spaun, Benjamin Norman. "A Ten-Fold Improvement to the Limit of the Electron Electric Dipole Moment." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11680.

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The Standard Model of particle physics is wonderfully successful in its predictions but known to be incomplete. It fails to explain the existence of dark matter, and the fact that a universe made of matter survived annihilation with antimatter following the big bang. Extensions to the Standard Model, such as weak-scale Supersymmetry, provide explanations for some of these phenomena by asserting the existence of new particles and new interactions that break symmetry under time-reversal. These theories predict a small, yet potentially measurable electron electric dipole moment (EDM), $d_e$, that also violates time-reversal symmetry. Here, we report a new measurement of the electron EDM in the polar molecule thorium monoxide (ThO): $d_e = -2.1 \pm 3.7stat \pm 2.5syst x 10-29$ e cm, which corresponds to an upper limit of $|d_e| <8.7 x 10-29$ e cm with 90 \% confidence. This is more than an order of magnitude improvement in sensitivity compared to the previous limit. This result sets strong constraints on new physics at an energy scale (TeV) at least as high as that directly probed by the Large Hadron Collider. The unprecedented precision of this EDM measurement was achieved by using the high effective electric field within ThO to greatly magnify the EDM signal. Valence electrons travel relativistically near the heavy thorium nucleus and experience an effective electric field of about 100 GV/cm, millions of times larger than any static laboratory field. The reported measurement is a combination of millions of separate EDM measurements performed with billions of ThO molecules in a cold, slow buffer gas beam. Other features of ThO, such as a near-zero magnetic moment and high electric polarizability, allow potential systematic errors to be drastically suppressed and ensure the accuracy of our measurement.
Physics

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6

Devlin, Jack Alexander. "Progress towards a more sensitive measurement of the electron electric dipole moment with YbF." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/28125.

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The electron is predicted to have a small electric dipole moment (eEDM), although so far no one has been able to measure this experimentally. The size of the eEDM is strongly connected to how badly time-reversal (T) symmetry is broken by nature. The Standard Model of particle physics, which has a small amount of T violation, predicts an unmeasurably tiny eEDM: de < 10^(-38) e cm. However, it is suggested that there should be additional T-violating processes to account for the matter-antimatter asymmetry in the universe. These could lead to a detectable eEDM near to the current limit |de|< 8.7*10^(-29) e cm (90\% confidence). Ramsey spectroscopy on paramagnetic, polar molecules has proved a very effective method for measuring eEDMs. In this thesis I explain the progress that has been made towards using ytterbium fluoride (YbF) for a new, improved measurement of the eEDM. I discuss the current operation of the experiment, and the systematic effects connected with the experiment. The statistical uncertainty of the experiment in analysed, and shown to be dominated by photon counting statistics. Then, a list of improvements to the machine are described, and simulated using rate equations and the optical Bloch equations. Taken together, these improvements enhance the sensitivity of the experiment by a factor of eleven, thus, it can be used in the near future to make a world-leading measurement of the electron EDM.

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7

Hutzler, Nicholas Richard. "A New Limit on the Electron Electric Dipole Moment| Beam Production, Data Interpretation, and Systematics." Thesis, Harvard University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3626724.

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The charge distribution associated with an electron has surprising implications for a number of outstanding mysteries in physics. Why is the universe made out of matter versus anti-matter, instead of both equally? What new particles and interactions lie beyond the current reach of accelerators like the LHC? Models which propose answers to these questions, such as Supersymmetry, tend to predict a small, yet potentially measurable, asymmetric interaction between an electron and an electric field, characterized by an electric dipole moment (EDM). Despite over six decades of experimental searching, no EDM of any fundamental particle has ever been measured; however, these experiments continue to provide some of the most stringent limits on new physics. Here, we present the results of a new search for the electron EDM, d_e = (-2.1 ± 3.7_stat ± 2.5syst) × 10^-29 e cm, which represents an order of magnitude improvement in sensitivity from the previous best limit. Since our measurement is consistent with zero, we present the upper limit of |d_e| < 8.7 × 10^-29 e cm with 90 percent confidence.

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8

Almond, James Robert. "Laser cooling of YbF molecules for an improved measurement of the electron electric dipole moment." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/47910.

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Cold molecules are attractive for a wide range of scientific applications, including quantum computation, the study of chemical reactions, and tests of fundamental physics. Laser cooling has proved to be an invaluable technique in the cooling of atoms. This technique was once thought to be infeasible for molecules, because it is difficult to find a closed cycling transition due to their vibrational structure. Recently, laser cooling of several diatomic species has been demonstrated. These molecules possess electronic transitions with highly diagonal Franck-Condon matrices, which make it possible to drive a quasi-closed cycling transition. Ytterbium fluoride (YbF) molecules are amenable to laser cooling and are especially interesting because they are used to measure the electron's electric dipole moment (eEDM). Measurements of the eEDM test the prediction of theories that extend the Standard Model of particle physics. The sensitivity of an eEDM experiment could be greatly increased by using ultracold molecules produced by direct laser cooling. This thesis presents work done towards producing a laser-cooled beam of YbF for an eEDM experiment. This work includes the construction of the cooling experiment, a novel method for efficiently combining laser beams of very similar frequencies, results of spectroscopic measurements to find the required transitions for laser cooling, the results of initial optical cycling experiments, and the first laser cooling results of YbF. Using a one-dimensional optical molasses, a beam of molecules is Doppler cooled in one transverse direction to a temperature of approximately 70 mK. Preliminary evidence of cooling to lower temperatures through a Sisyphus mechanism is also presented. Finally, paths towards improving the laser cooling are suggested. The work opens the door to improved measurements of the eEDM using ultracold YbF molecules.

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9

Kara, Dhiren Manji. "Toward an electron electric diploe moment measurement using Ytterbium fluoride." Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.536009.

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10

Chan, Chuan-Tsung. "Neutron electric dipole moment from QCD sum rules /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/9708.

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11

Zenner, Johannes [Verfasser]. "The search for the neutron electric dipole moment / Johannes Zenner." Mainz : Universitätsbibliothek Mainz, 2013. http://d-nb.info/1041244924/34.

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12

Gurevich, Yulia. "Preliminary Measurements for an Electron EDM Experiment in ThO." Thesis, Harvard University, 2011. http://dissertations.umi.com/gsas.harvard:10037.

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The ACME collaboration aims to measure the eEDM via Ramsey spectroscopy of a cryogenic beam of ThO molecules in their metastable H state. This thesis describes the launch of this new experimental effort. A set of diode lasers has been built to address all the necessary ThO transitions. The laser frequencies were stabilized to a stable reference laser via a $Fabry-P\acute{e}rot$ transfer cavity. A measurement of the magnetic dipole moment of the H state has been performed that is complementary to a previous measurement by the collaboration. This value is important for determining the sensitivity of the H state to magnetic fields, which can be a source of noise and systematic errors in the eEDM measurement. Experimental efforts to prepare the coherent superposition of the $M = \pm1$ Zeeman sublevels in the H,J = 1 state that is the starting point of the eEDM experiment using transitions to the G state resulted in a better understanding of transitions between $\Omega$-doublet states in an electric field. This led to a new technique for normalizing out shot-to-shot fluctuations in the molecular beam flux, which has also been demonstrated experimentally.
Physics

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13

Grozier, James R. "The cryogenic neutron electric dipole moment experiment : magnetic challenges and solutions." Thesis, University of Sussex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444372.

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14

Nouri, Nima. "MAGNETIC FIELD NON-UNIFORMITY CHALLENGES IN NEUTRON ELECTRIC DIPOLE MOMENT EXPERIMENTS." UKnowledge, 2016. http://uknowledge.uky.edu/physastron_etds/38.

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A new neutron Electric Dipole Moment (nEDM) experiment was proposed to be commissioned at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source (SNS) of the Oak Ridge National Laboratory (ORNL). The underlying theme of this experiment (first conceived by Golub and Lamoreaux in 1994) is the search for new physics beyond the Standard Model of particle physics. The discovery of a non-zero nEDM would be of revolutionary importance to physics, with the discovery of such providing for evidence for new-beyond-the-Standard-Model physics required for a resolution to the unresolved puzzle of why the universe is dominated by matter, as opposed to anti-matter. A first demonstration of a new magnetic field monitoring system for a neutron electric dipole moment experiment is presented. The system is designed to reconstruct the vector components of the magnetic field in the interior measurement region solely from exterior measurements. The results highlight the potential for the implementation of an improved system in an upcoming neutron electric dipole moment experiment to be carried out at the Spallation Neutron Source at Oak Ridge National Laboratory.

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15

Santos, George de Conto. "Electron and muon anomalous magnetic dipole moment in the 3-3-1 model with heavy leptons." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/153288.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Nós calculamos, no contexto do modelo 3-3-1 com léptons pesados carregados, vínculos sobre alguns dos parâmetros das partículas extras do modelo ao impor que suas contribuições aos fatores (g-2) do elétron e do múon estejam de acordo com os dados experimentais dentro de 1 sigma - 3 sigma. Para obter resultados realistas nós consideramos algumas das possíveis soluções das matrizes unitárias esquerda e direita que diagonalizam as matrizes de massa leptônicas, dando as massas leptônicas observadas e ao mesmo tempo acomodando a matriz de mistura de Pontecorvo-Maki-Nakagawa-Sakata (PMNS). Nós mostramos que, ao menos até a ordem de 1-loop, na faixa de parâmetros explorada, não é possível acomodar simultaneamente os fatores (g-2) do elétron e do múon a não ser que um dos léptons extras tenha massa da ordem de 20-40 GeVs e a escala de energia da simetria 331 esteja em torno de 60-80 TeVs.
We calculate, in the context of the 3-3-1 model with heavy charged leptons, constraints on some parameters of the extra particles in the model by imposing that their contributions to both the electron and muon (g-2) factors are in agreement with experimental data up to 1 sigma - 3 sigma. In order to obtain realistic results we use some of the possible solutions of the left- and right- unitary matrices that diagonalize the lepton mass matrices, giving the observed lepton masses and at the same time allowing to accommodate the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. We show that, at least up to 1-loop order, in the particular range of the space parameter that we have explored, it is not possible to fit the observed electron and muon (g-2) factors at the same time unless one of the extra leptons has a mass of the order of 20-40 GeVs and the energy scale of the 331 symmetry to be of around 60-80 TeVs.
152740/2014-7

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16

Karamath, James Robert. "He-II under high electric field conditions for the cryogenic neutron electric dipole moment experiment." Thesis, University of Sussex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444370.

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17

Kalita, Mukut R. "Search for a Permanent Electric Dipole Moment of ²²⁵Ra." UKnowledge, 2015. http://uknowledge.uky.edu/physastron_etds/34.

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The observation of a permanent electric dipole moment (EDM) in a non-degenerate system would indicate the violation of discrete symmetries of Time reversal (T) or combined application of Charge (C) and Parity (P) symmetry violation through the CPT theorem. The diamagnetic 225Ra atom with nuclear spin I=1/2 is a favorable candidate for an EDM search. Experimental sensitivity to its EDM is enhanced due to its high atomic mass and the increased Schiff moment of its octupole deformed nucleus. An experimental setup is developed where laser cooled neutral radium atoms are collected in a magneto-optical trap (MOT). The collected atoms are transported 1 meter with a far off-resonant optical dipole trap (ODT) and then the atoms are transferred to a second standing-wave ODT in an experimental chamber. The atoms are then optically polarized and allowed to Larmor precess in parallel and antiparallel electric and magnetic fields. The difference between the Larmor precession frequency for parallel and antiparallel fields is experimentally determined to measure the EDM. This thesis is about the first measurement of the EDM of the 225Ra atom where an upper limit of |d(225Ra)|<5.0*10-22 e cm (95\% confidence) is reached.

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18

Pattie, Robert W. Jr. "Status of the Los Alamos Room Temperature Neutorn Electric Dipole Moment Search." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etsu-works/5532.

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A discovery of the neutron's permanent electric dipole moment larger than the standard model prediction of dn ≈ 10-31 e·cm would signal a new source of CP-violation and help explain the matter-antimatter asymmetry in the universe. Tightening the limits on dn constrain extensions to the standard model in a complementary fashion to the atomic and electron EDM searches. The recent upgrade of the Los Alamos ultracold neutron source makes it possible for a new room temperature search with the statistical reach to improve upon current limits by a factor of 10 or more. During the 2018 LANSCE cycle a prototype apparatus was used to demonstrate the capability to transport and manipulate polarized neutrons and perform Ramsey and Rabi sequence measurements. I will report on the measurements made over the last year, efforts underway to upgrade the prototype chamber, and possible future upgrades of the ultracold neutron source.

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19

Hamzaoui, C. "CP violation in gauge theories and the electric dipole moment of the neutron." Thesis, University of Sussex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377048.

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20

Dadisman, James Ryan. "MAGNETIC FIELD DESIGN TO REDUCE SYSTEMATIC EFFECTS IN NEUTRON ELECTRIC DIPOLE MOMENT MEASUREMENTS." UKnowledge, 2018. https://uknowledge.uky.edu/physastron_etds/53.

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Charge-Conjugation (C) and Charge-Conjugation-Parity (CP) Violation is one of the three Sakharov conditions to explain via baryogenesis the observed baryon asymmetry of the universe (BAU). The Standard Model of particle physics (SM) contains sources of CP violation, but cannot explain the BAU. This motivates searches for new physics beyond the standard model (BSM) which address the Sakharov criteria, including high-precision searches for new sources of CPV in systems for which the SM contribution is small, but larger effects may be present in BSM theories. A promising example is the search for the electric dipole moment of the neutron (nEDM), which is a novel system to observe CPV due to the initial and final state being identical. A non-zero measurement necessarily requires violation of P and T discrete symmetries; invoking CPT invariance requires that CP is violated. There are BSM theories which predict a magnitude for the nEDM larger than SM predictions, so that such studies are beneficial at setting constraints on new physics. The current experimental limit of dn < 3.0 x 10-26 e cm at 90% CL as set by the Institut Laue-Langevin (ILL) [1] was largely limited by systematic effects related to the magnetic field. The research presented here supported technical progress toward a new measurement of the nEDM, with the goal of improving the result by an order of magnitude. A novel approach to the problem of limiting systematics is proposed, studied in Monte Carlo simulations, and an optimized prototype was constructed for use in a magnetic resonance experiment.

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21

Miranda, P. M. C. "Contributions to the search for a neutron EDM." Thesis, University of Sussex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375844.

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The work described in this thesis was carried out at the Institut Laue Langevin, Grenoble, France as a member of the group searching for the electric dipole moment (EDM) of the neutron. The first chapter is an introduction to ultra-cold neutrons (UCN) and their use in the search for an EDM. In chapter two a description is given of the data acquisition procedure and the data analysis method as well as a discussion of the various sources of spurious EDM signals. The data taken by the author yielded the result I-fe/e = ( -3.7 ± 5.4 )xl0-25 cm, which together' with all the other data previously and subsequently collected on PN5 gives I-fe/e = ( -3.7 ± 5.4 )xlO- 25 cm. The third chapter contains some calculations, based on a simple model of the polarizer's properties, of the time dependence of the polarized UCN density in the apparatus during a data ~cquisition cycle. It. also includes the results of the experiments made in an attempt to determine experimentally the model's parameters. The other two chapters are concerned with the problem of transferring efficiently UCN from the 0.6 K volume of the 4He superthermal source to thf! 300 K EDM apparatus without allowing the heat transfer by radiation to overload the source's refrigerator. The possibility of using metal coated polypropylene windows to achieve this aim is investigated in the fourth chapter. In chapter five the infra-red transmission of the stainless steel neutron guides is estimated by calculation and then determined experimentally with a view to using lengths of cold guides to attenuate the radiation heat transfer from the apparatus to the source.

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22

Cottle, Amy. "Development of a SQUID magnetometry system for a cryogenic neutron electric dipole moment experiment." Thesis, University of Oxford, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.711932.

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23

Liang, Anthony. "Electric deflection measurements of sodium clusters in a molecular beam." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31750.

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Thesis (Ph.D)--Physics, Georgia Institute of Technology, 2010.
Committee Chair: de Heer, Walter; Committee Member: Chou, Mei-Yin; Committee Member: First, Phillip; Committee Member: Whetten, Robert; Committee Member: Zangwill, Andrew. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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24

Malkowski, Susan Kate. "MAGNETIC SHIELDING STUDIES FOR THE NEUTRON ELECTRIC DIPOLE MOMENT EXPERIMENT AT THE SPALLATION NEUTRON SOURCE." UKnowledge, 2011. http://uknowledge.uky.edu/physastron_etds/1.

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The neutron Electric Dipole Moment Experiment at the Spallation Neutron Source requires an overall magnetic shielding factor of order 105 to attenuate external background magnetic fields. At present, the shielding design includes an external (room-temperature) multi-layer μ-metal magnetic shield, a cryogenic (4 Kelvin) Pb superconducting shield, and a cryogenic (4 Kelvin) ferromagnetic shield composed of Metglas ribbon. This research determined how to construct a Metglas shield using minimal material that produced axial and transverse shielding factors of ~267 and ~1500. In addition, the μ-metal and Metglas shields were modeled using finite element analysis. The FEA model includes external coils and their effect on the residual magnetic fields. This study will help with the design of the shielding.

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25

Hess, Paul William. "Improving the Limit on the Electron EDM: Data Acquisition and Systematics Studies in the ACME Experiment." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11679.

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The ACME collaboration has completed a measurement setting a new upper limit on the size of the electron's permanent electric dipole moment (EDM). The existence of the EDM is well motivated by theories extending the standard model of particle physics, with predicted sizes very close to the current experimental limit. The new limit was set by measuring spin precession within the metastable H state of the polar molecule thorium monoxide (ThO). A particular focus here is on the automated data acquisition system developed to search for a precession phase odd under internal and external reversal of the electric field. Automated switching of many different experimental controls allowed a rapid diagnosis of major systematics, including the dominant systematic caused by non-reversing electric fields and laser polarization gradients. Polarimetry measurements made it possible to quantify and minimize the polarization gradients in our state preparation and probe lasers. Three separate measurements were used to determine the electric field that did not reverse when we tried to switch the field direction. The new bound of |de|< 8.7 × 10^-29 e cm is over an order of magnitude smaller than previous limits, and strongly limits T-violating physics at TeV energy scales.
Physics

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26

Griffith, William Clark. "Limiting CP violation through a search for a permanent electric dipole moment of mercury 199 atoms /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/9760.

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27

Flaux, Pierrick. "Measurement of the neutron electric dipole moment at the Paul Scherrer Institute : production of magnetic fields." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC222/document.

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Le travail réalisé au cours de cette thèse concerne le développement du système de bobines de l'expérience n2EDM à l'Institut Paul Sherrer (PSI). Le but de cette expérience est de mettre en évidence de nouvelles sources de violation CP à travers la mesure du moment dipolaire électrique du neutron. L'actuelle limite supérieure sur la mesure de nEDM, $2.9 \cross 10^{-26}$ e.cm (90\% C.L.) à été obtenue par la collaboration RAL-Sussex-ILL en 2006.L'expérience n2EDM vise à améliorer d'un ordre de grandeur la sensibilité statistique en gardant sous contrôle les effets systématiques. Cela requiert la production d'un champ magnétique très uniforme. Les non-uniformités de ce dernier sont en effet responsable de la dépolarisation des neutrons et impliqués dans plusieurs effets systématiques.Dans le premier chapitre, les motivations physiques sont discutées.Le second chapitre décrit le principe de mesure de l'expérience n2EDM, ainsi que l'importance de l'uniformité du champ magnétique. Le chapitre s'achève par une présentation globale du dispositif expérimental.Le troisième chapitre présente le logiciel COMSOL et discute du design et des performances de la bobine B$_{0}$, en charge de la production du champ magnétique principal.Dans le quatrième chapitre, le système de bobines correctrices chargées de corriger les non-uniformités du champ magnétique et celles devant produire des gradients spécifiques sont présentées.Finalement, le cinquième et dernier chapitre présente l'étude des dipôles magnétiques localisés et de leur influence sur l'expérience
This work presents the design of the coils system developed for the n2EDM experiment at the Paul Sherrer Institute (PSI). The goal of this experiment is to reveal new sources of CP violation through the measurement of the neutron electric dipole moment. The current upper limit of the nEDM measurement, $2.9 \cross 10^{-26}$ e.cm (90\% C.L.) was achieved by the RAL-Sussex-ILL collaboration in 2006.The n2EDM experiment aims at improving by one order of magnitude the statistical sensitivity while keeping under control the systematics effects. It requires to produce a very uniform field, its non-uniformities being responsible of the neutron's depolarization and of severals systematic effects.In the first chapter, the theoretical motivation are discussed.The second chapter describes the measurement principle of the n2EDM experiment, as well as the importance of the magnetic field uniformity. This chapter ends by an overview of the apparatus.The third chapter introduces the COMSOL software and discuss the design and the performances of the B0 coil, in charge of the production of the main magnetic field.In the fourth chapter, the correcting coils used to suppress the non-uniformities of the magnetic field and the ones which produce specific gradients are presented.Finally, the fifth and last chapter talks about the study of localised magnetic dipoles and their influence on the experiment

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28

Santos, George De Conto. "Electron and muon anomalous magnetic dipole moment in the 3-3-1 model with heavy leptons /." São Paulo, 2018. http://hdl.handle.net/11449/153288.

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Orientador: Vicente Pleitez
Banca: Juan Carlos Montero Garcia
Banca: Ricardo D'Elia Matheus
Banca: João Pacheco Bicudo Cabral de Melo
Banca: Marcelo Moraes Guzzo
Resumo: Nós calculamos, no contexto do modelo 3-3-1 com léptons pesados carregados, vínculos sobre alguns dos parâmetros das partículas extras do modelo ao impor que suas contribuições aos fatores (g-2) do elétron e do múon estejam de acordo com os dados experimentais dentro de 1 sigma - 3 sigma. Para obter resultados realistas nós consideramos algumas das possíveis soluções das matrizes unitárias esquerda e direita que diagonalizam as matrizes de massa leptônicas, dando as massas leptônicas observadas e ao mesmo tempo acomodando a matriz de mistura de Pontecorvo-Maki-Nakagawa-Sakata (PMNS). Nós mostramos que, ao menos até a ordem de 1-loop, na faixa de parâmetros explorada, não é possível acomodar simultaneamente os fatores (g-2) do elétron e do múon a não ser que um dos léptons extras tenha massa da ordem de 20-40 GeVs e a escala de energia da simetria 331 esteja em torno de 60-80 TeVs.
Abstract: We calculate, in the context of the 3-3-1 model with heavy charged leptons, constraints on some parameters of the extra particles in the model by imposing that their contributions to both the electron and muon (g �� 2) factors are in agreement with experimental data up to 1 -3 . In order to obtain realistic results we use some of the possible solutions of the left- and right- unitary matrices that diagonalize the lepton mass matrices, giving the observed lepton masses and at the same time allowing to accommodate the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. We show that, at least up to 1-loop order, in the particular range of the space parameter that we have explored, it is not possible to t the observed electron and muon (g �� 2) factors at the same time unless one of the extra leptons has a mass of the order of 20-40 GeVs and the energy scale of the 331 symmetry to be of around 60-80 TeVs
Doutor

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May, Daniel John Robert. "A high precision comparison of the gyromagnetic ratios of the '1'9'9Hg atom and the neutron." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285111.

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30

Müller, Fabian Verfasser], Jörg [Akademischer Betreuer] [Pretz, and Lutz [Akademischer Betreuer] Feld. "Polarimeter development for electric dipole moment measurements in storage rings / Fabian Müller ; Jörg Johannes Pretz, Lutz Feld." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/121592755X/34.

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Müller, Fabian [Verfasser], Jörg [Akademischer Betreuer] Pretz, and Lutz [Akademischer Betreuer] Feld. "Polarimeter development for electric dipole moment measurements in storage rings / Fabian Müller ; Jörg Johannes Pretz, Lutz Feld." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/121592755X/34.

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32

Aleksandrova, Alina. "Magnetic Field Monitoring in the SNS Neutron EDM Experiment." UKnowledge, 2019. https://uknowledge.uky.edu/physastron_etds/68.

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It is a well known fact that the visible universe is made almost entirely of baryonic matter. Yet, this is also one of the greatest puzzles that physicists are trying to solve: Where did all of this matter come from in the first place? The Standard Model (SM) of particle physics predicts a baryon asymmetry that is much smaller than what is observed in nature. In order to try and explain this discrepancy, Sakharov (1967) postulated three necessary conditions for baryogenesis in the early universe. One of these is the requirement that charge conjugation (C) and the product of C and parity (P) symmetries are violated. Because the SM fails to generate the observed baryon asymmetry, additional sources of CP violation are needed in order to help reconcile theory and observation. Thus, physicists have been looking for extensions to the SM in search of an answer. The presence of a neutron Electric Dipole Moment (nEDM) would signal a new source of CP violation. A non-vanishing nEDM would provide evidence for the breaking of both parity (P) and time-reversal symmetry (T). Because CPT symmetry is assumed to be conserved and has not been found to be broken, this would signal CP violation. To look for an nEDM, stored ultracold neutrons are placed in parallel and anti-parallel magnetic and electric fields and the Larmor precession frequency is carefully measured. A difference in the precession frequency of the neutrons in the two states of the fields would signal the existence of an nEDM. The current upper limit of the nEDM was set by the RAL-Sussex-ILL collaboration and stands at dn < 3.0x10-26 e cm (90% CL). Currently a new cryogenic apparatus is under construction at the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory (ORNL) which aims to reduce the current upper limit by two orders of magnitude. A central problem to all neutron EDM experiments is the generation of a highly uniform and stable magnetic field. Because the suppression of systematic effects that arise from magnetic field nonuniformities and temporal drifts is vital to the success of these experiments, it is important to have the ability to precisely control and monitor the magnetic field gradients inside of the experimental volume. However, it is not always possible to measure the field gradients within the region of interest directly. To remedy this issue in the SNS nEDM experiment, a field monitoring system has been designed and tested that will allow for the reconstruction of the field gradients inside of the fiducial volume using noninvasive measurements of the field components at discrete locations external to this volume. This document will outline the theoretical framework of our method and present the results of experimental and simulated studies performed and the engineering design for such a field monitoring system.

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Rayyan, Saifuddin Ramadan. "Phenomenological Consequences of Heavy Right Handed Neutrinos." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27879.

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The discovery of neutrino mixing provides the possibility of a non vanishing CP violating phase in the neutrino mixing matrix. CP violation in the leptonic sector can be large enough to explain the matter-antimatter asymmetry in the universe. An indirect probe of CP violation is the experimental measurement of Electric Dipole Moment (EDM). CP violation has been discovered in the quark sector,but it contributes to lepton EDM at the 3-loop level. Neutrino masses can be generated in the standard model via the see-saw mechanism where heavy right-handed neutrinos mix with the weak-basis states. The Majorana nature of the seesaw type neutrinos generates new 2-loop diagrams that lead to a non-vanishing lepton EDM. Only estimates of the resulting EDM have been done in the literature. A full calculation of the 2-loop diagrams and the exact result is presented.
Ph. D.

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O'Leary, Brendon R. "In search of the electron's electric dipole moment in thorium monoxide| An improved upper limit, systematic error models, and apparatus upgrades." Thesis, Yale University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10633259.

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Searches for violations of discrete symmetries can be sensitive probes of physics beyond the Standard Model. Many models, such as supersymmetric theories, introduce new particles at higher masses that include new CP-violating phases which are thought to be of order unity. Such phases could generate measurable permanant electric dipole moments (EDMs) of particles. The ACME collaboration has measured the electron's EDM to be consistent with zero with an order of magnitude improvement in precision compared to the previous best precision (J. Baron et al., ACME collaboration, Science 343 (2014), 269-272) with a spin precession measurement performed in the H state of a beam of thorium monoxide (ThO). This limit constrains time-reversal violating physics for particles with masses well into the TeV scale. In this thesis I discuss the details of this measurement with an emphasis on the data analysis, search for systematic errors, and systematic error models that contributed to this result. I also discuss implemented and planned upgrades to the experimental apparatus intended to both improve the statistical sensitivity and reduce its susceptibility to systematic errors. At this time, the upgraded apparatus has been demonstrated to have a statistical sensitivity to the electron EDM that is more than a factor of 10x more precise than our previous measurement.

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35

Kuchler, Florian [Verfasser], Peter [Akademischer Betreuer] Fierlinger, and Elisa [Akademischer Betreuer] Resconi. "Electric dipole moment searches using the isotope 129-xenon / Florian Kuchler. Betreuer: Peter Fierlinger. Gutachter: Peter Fierlinger ; Elisa Resconi." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1088724973/34.

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36

Zimmer, Stefan [Verfasser]. "Search for a permanent electric dipole moment of 129 Xe with a He/Xe clock-comparison experiment / Stefan Zimmer." Mainz : Universitätsbibliothek Mainz, 2018. http://d-nb.info/1161614397/34.

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37

McCann, Michael Andrew. "Magnetometery for cryoEDM." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:0a503382-d356-4fd6-b877-65bd00df331b.

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The existence of the matter in the universe is still an unsolved puzzle. After the Big Bang, both matter and antimatter should have been created in equal amounts, and subsequently annihilated. The leading theories to explain the existence of matter require an imbalance in the production of matter and antimatter in the early universe. This in turn requires CP violation, an asymmetry of the laws of physics between matter and antimatter. cryoEDM is designed to explore the total amount of CP violation and resolve this issue. cryoEDM is a next-generation neutron electric dipole moment search in a commissioning phase of development at the Institut Laue-Langevin, Grenoble. A critical requirement of EDM searches is knowledge of the magnetic environment. This work is concerned with the development, implementation, and performance of the currently operating magnetometry system based on SQUID magnetometers. An analysis scheme to provide magnetometry data over the volume occupied by the neutrons, from measurements using the available magnetometers, is developed. An updated method to calibrate the magnetometers using internal sources of magnetic fields is presented, and found to give good agreement with independent measurements. A new method of calibration using the neutrons as a reference is discussed, and tests on an example arrangement are shown to be promising. Algorithms for detecting and correcting for hardware induced artefacts in the data are produced, and demonstrated to reconstruct the field with good agreement in all but the noisiest environments. A software framework is developed to combine these into a real-time analysis that provides feedback and diagnostics to the experiment. Using this new system the resolution of the magnetometers installed in cryoEDM is found to be limited by the environmental noise, and would give a false EDM signal that is greater than the statistical uncertainty in neutron counting. However, the resolution has been somewhat artificially limited to reduce the susceptibility to the RF interference present. This still allows the magnetometry to act as a useful diagnostic tool on any issues in the current magnetic environment, even if in a sub-optimal configuration. For example, investigation of the magnetic shielding of the experiment finds a reduction in the shielding relative to the design, a situation which is being addressed with the design of additional shielding. Once this shielding is installed the resolution of the magnetometers will improve as well as the slew rate of the SQUIDs, which is found to be lower than the $47,mu extup{Ts}^{-1}$ required to measure AC fields applied during a measurement. The current system can also determine sources of magnetic perturbations created within the experiment, which will require addressing before a full EDM run can be performed. For example, cryogenic effects are observed to occur approximately hourly causing large shifts in the magnetic field. Also operation of valves controlling the flow of neutrons around the experiment are found to produce both AC magnetic fields from the driving motors, and shifts in the field from their movement. Situations which can be resolved by reexamination of installation and operational procedures.

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38

Chekmenev, Stanislav Verfasser], Jörg [Akademischer Betreuer] [Pretz, and Yury [Akademischer Betreuer] Senichev. "Investigation of possibilities to measure the deuteron electric dipole moment at storage rings / Stanislav Chekmenev ; Jörg Johannes Pretz, Yury Senichev." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/116249820X/34.

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39

Chekmenev, Stanislav [Verfasser], Jörg [Akademischer Betreuer] Pretz, and Yury [Akademischer Betreuer] Senichev. "Investigation of possibilities to measure the deuteron electric dipole moment at storage rings / Stanislav Chekmenev ; Jörg Johannes Pretz, Yury Senichev." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/116249820X/34.

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40

Hinder, Fabian Verfasser], Jörg [Akademischer Betreuer] [Pretz, and Lutz Werner [Akademischer Betreuer] Feld. "Development of beam diagnostic systems for electric dipole moment measurements at particle accelerators / Fabian Hinder ; Jörg Johannes Pretz, Lutz Werner Feld." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1170680178/34.

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41

Hempelmann, Nils Verfasser], Jörg [Akademischer Betreuer] [Pretz, Achim [Akademischer Betreuer] Stahl, and Ralf [Akademischer Betreuer] Gebel. "Polarization measurement and manipulation for electric dipole moment measurements in storage rings / Nils Hempelmann ; Jörg Johannes Pretz, Achim Stahl, Ralf Gebel." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1169754945/34.

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42

Hempelmann, Nils [Verfasser], Jörg [Akademischer Betreuer] Pretz, Achim [Akademischer Betreuer] Stahl, and Ralf [Akademischer Betreuer] Gebel. "Polarization measurement and manipulation for electric dipole moment measurements in storage rings / Nils Hempelmann ; Jörg Johannes Pretz, Achim Stahl, Ralf Gebel." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1169754945/34.

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43

Hinder, Fabian [Verfasser], Jörg [Akademischer Betreuer] Pretz, and Lutz Werner [Akademischer Betreuer] Feld. "Development of beam diagnostic systems for electric dipole moment measurements at particle accelerators / Fabian Hinder ; Jörg Johannes Pretz, Lutz Werner Feld." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1170680178/34.

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44

Trinkel, Fabian Verfasser], Jörg [Akademischer Betreuer] [Pretz, and Kurt [Akademischer Betreuer] Aulenbacher. "Development of a Rogowski coil beam position monitor for electric dipole moment measurements at storage rings / Fabian Trinkel ; Jörg Johannes Pretz, Kurt Aulenbacher." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1162846038/34.

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45

Trinkel, Fabian [Verfasser], Jörg [Akademischer Betreuer] Pretz, and Kurt [Akademischer Betreuer] Aulenbacher. "Development of a Rogowski coil beam position monitor for electric dipole moment measurements at storage rings / Fabian Trinkel ; Jörg Johannes Pretz, Kurt Aulenbacher." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1162846038/34.

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46

Rosenthal, Marcel Verfasser], Jörg [Akademischer Betreuer] [Pretz, A. [Akademischer Betreuer] Lehrach, and Kurt [Akademischer Betreuer] Aulenbacher. "Experimental benchmarking of spin tracking algorithms for electric dipole moment searches at the cooler synchrotron COSY / Marcel Rosenthal ; Jörg Pretz, A. Lehrach, Kurt Aulenbacher." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1130352447/34.

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47

Rosenthal, Marcel Stephan [Verfasser], Jörg [Akademischer Betreuer] Pretz, A. [Akademischer Betreuer] Lehrach, and Kurt [Akademischer Betreuer] Aulenbacher. "Experimental benchmarking of spin tracking algorithms for electric dipole moment searches at the cooler synchrotron COSY / Marcel Rosenthal ; Jörg Pretz, A. Lehrach, Kurt Aulenbacher." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1130352447/34.

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48

Mereghetti, Emanuele. "Application of Effective Field Theories to Problems in Nuclear and Hadronic Physics." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/202538.

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The Effective Field Theory formalism is applied to the study of problems in hadronic and nuclear physics. We develop a framework to study the exclusive two-body decays of bottomonium into two charmed mesons and apply it to study the decays of the C-even bottomonia. Using a sequence of effective field theories, we take advantage of the separation between the scales contributing to the decay processes, 2m(b) ≫ m(c) ≫∧(QCD). We prove that, at leading order in the EFT power counting, the decay rate factorizes into the convolution of two perturbative matching coefficients and three non-perturbative matrix elements, one for each hadron. We calculate the relations between the decay rate and non-perturbative bottomonium and D-meson matrix elements at leading order, with next-to-leading log resummation. The phenomenological implications of these relations are discussed. At lower energies, we use Chiral Perturbation Theory and nuclear EFTs to set up a framework for the study of time reversal (T) symmetry in one- and few-nucleon problems. We consider T violation from the QCD θ term and from all the possible dimension 6 operators, expressed in terms of light quarks, gluons and photons, that can be added to the Standard Model Lagrangian. We construct the low energy chiral Lagrangian stemming from different TV sources, and derive the implications for the nucleon Electric Dipole Form Factor and the deuteron T violating electromagnetic Form Factors. Finally, with an eye to applications to nuclei with A ≥ 2, we construct the T violating nucleon-nucleon potential from different sources of T violation.

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Poncza, Vera [Verfasser], Andreas [Akademischer Betreuer] Lehrach, Andrzej [Akademischer Betreuer] Magiera, and Achim [Akademischer Betreuer] Stahl. "Extensive optimization of a simulation model for the electric dipole moment measurement at the Cooler Synchrotron COSY / Vera Poncza ; Andreas Lehrach, Andrzej Magiera, Achim Stahl." Aachen : Universitätsbibliothek der RWTH Aachen, 2021. http://d-nb.info/1239116799/34.

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Zechlau, Thorsten Sven [Verfasser], Peter [Akademischer Betreuer] [Gutachter] Fierlinger, and Winfried [Gutachter] Petry. "Ultra-Cold Neutron Transport and Spin Manipulation System for the Measurement of the Neutron Electric Dipole Moment / Thorsten Sven Zechlau ; Gutachter: Peter Fierlinger, Winfried Petry ; Betreuer: Peter Fierlinger." München : Universitätsbibliothek der TU München, 2016. http://d-nb.info/1120013925/34.

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Dissertations / Theses on the topic 'Electric Dipole Moment of the electron'

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