Relevant bibliographies by topics / Atomes neutres

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Academic literature on the topic 'Atomes neutres'

Author: Grafiati
Published: 25 May 2024
Last updated: 15 March 2025

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Journal articles on the topic "Atomes neutres"

1

Atiyah, M. F., and N. S. Manton. "Complex geometry of nuclei and atoms." International Journal of Modern Physics A 33, no. 24 (August 30, 2018): 1830022. http://dx.doi.org/10.1142/s0217751x18300223.

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We propose a new geometrical model of matter, in which neutral atoms are modelled by compact, complex algebraic surfaces. Proton and neutron numbers are determined by a surface’s Chern numbers. Equivalently, they are determined by combinations of the Hodge numbers, or the Betti numbers. Geometrical constraints on algebraic surfaces allow just a finite range of neutron numbers for a given proton number. This range encompasses the known isotopes.
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Kirichenko, A. N., A. V. Krasilnikov, N. B. Rodionov, V. P. Rodionova, A. G. Trapeznikov, V. P. Yartsev, S. A. Meshchaninov, K. K. Artemev, R. A. Khmel’nitskii, and V. N. Amosov. "Spectrometers of Neutrons and Fast Atoms of Tokamak Thermonuclear Plasma Based on CVD Synthesized Diamond Single-Crystal Films." Fizika plazmy 50, no. 4 (November 27, 2024): 484–90. http://dx.doi.org/10.31857/s0367292124040082.

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High radiation resistance, chemical inertness, the ability to operate at elevated temperatures, high mobility and efficiency of charge-carrier collection are important properties of diamond for designing detectors and spectrometers of ionizing radiation. Currently, diagnostics of neutrons and neutral particle fluxes based on diamond detectors for the ITER thermonuclear reactor are justified and developed. This work presents the results of a Raman spectroscopy and photoluminescence spectroscopy study of the electronic quality of synthesized epitaxial diamond films obtained by vapor deposition in a hydrogen and methane mixture in the ARDIS reactor on boron-doped single-crystal diamond substrates. To confirm their electronic quality, detectors have been made from films selected by spectrometric methods and the charge collection efficiency and energy resolution have been measured when irradiated with alpha particles from a 241Am source and 14.7 MeV fast neutrons from the ING-07T2 neutron generator.
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Naghiyev, T. G. "Neutron-alpha reactions in nano α-Si3N4 particles by neutrons." Modern Physics Letters A 36, no. 24 (August 10, 2021): 2150181. http://dx.doi.org/10.1142/s0217732321501819.

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Computer modeling was applied to the study of [Formula: see text] transmutations in [Formula: see text] nanoparticles under the influence of neutrons at different energies. The modeling was separately performed for each Si and N atoms in the [Formula: see text] nanoparticles and the effect of neutrons on transmutations was investigated. The simulations were conducted individually for each stable isotope due to different effective cross-section of the probability of transmutation in the different types of isotopes of silicon and nitrogen atoms. Effective cross-section spectra of [Formula: see text] transmutation in Si and N atoms were comparatively studied.
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Mason, T. E., and A. D. Taylor. "Neutron Scattering in Materials Research." MRS Bulletin 24, no. 12 (December 1999): 14–16. http://dx.doi.org/10.1557/s0883769400053665.

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With materials of ever-increasing complexity becoming key elements of the technologies underpinning industrial and economic development, there is an ongoing need for tools that reveal the microscopic origins of physical, electrical, magnetic, chemical, and biological properties. Neutron scattering is one such powerful tool for the study of the structure and dynamics of materials. Neutrons are well suited to this purpose for several reasons:∎ Neutrons are electrically neutral, leading to penetration depths of centimeters and thereby enabling in situ studies.∎ Neutron cross sections exhibit no regular dependence on atomic number and are similar in magnitude across the periodic table, giving rise to sensitivity to light elements in the presence of heavier ones.∎ Certain large differences in isotopic scattering cross sections (e.g., hydrogen to deuterium, H/D) make neutrons especially useful for the study of light atoms in materials.∎ The range of momentum transfer available allows probing of a broad range of length scales (0.1–105 Å), important in many different materials and applications.∎ Thermal and “cold” (longer-wavelength) neutrons cover a range of energies sufficient to probe a wide range of lattice or magnetic excitations, “slow” dynamic processes such as polymer chain reptation, and so forth.∎ Neutrons have magnetic moments and are thus uniquely sensitive probes of magnetic interactions.∎ Neutrons can be polarized, allowing the cross sections (magnetic and non-magnetic) to be separated.∎ The simplicity of the magnetic and nuclear interactions makes interpretation of results straightforward.
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Monti, V., M. Costa, E. Durisi, E. Mafucci, A. Calamida, A. I. Castro Campoy, A. Fontanilla, L. Russo, and R. Bedogni. "Neutron spectroscopy for Boron Neutron Capture Therapy beams characterization." Journal of Instrumentation 19, no. 05 (May 1, 2024): C05036. http://dx.doi.org/10.1088/1748-0221/19/05/c05036.

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Abstract Boron Neutron Capture Therapy (BNCT) is a therapeutic treatment for malignant tumors that utilizes the nuclear reactions that happen when thermal neutrons are captured by boron-10 atoms to selectively destroy designated cells. Boron-10 atoms are biochemically accumulated inside the tumor target, which is then irradiated with thermal neutrons. In recent years, the possibility to obtain accelerator based intense neutron beams has given a boost to the diffusion of BNCT also in Europe, removing the need of nuclear reactors. In this contest, the monitoring and characterization of the epithermal neutron beams dedicated to BNCT becomes an important issue. The directional neutron spectrometer called NCT-WES (Neutron Capture Therapy Wide Energy Spectrometer) is a single moderator neutron spectrometer composed of a polyethylene cylinder embedding six semiconductor-based detectors positioned at different depths along the cylinder axes. The position of the six detectors is studied in order to maximize the response of each one in a selected neutron energy range. The unfolding of the six simultaneous readings allows to reconstruct the incoming neutron energy spectrum as in a parallelized Bonner Sphere System. A cylindrical collimator situated in the front of the spectrometer makes the instrument sensitive to neutrons coming only from a given direction, which allows to exclude the contribution of the room scattered radiation. The experimental validation of the spectrometer, obtained through several measuring campaigns, is reported and discussed.
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Morris, Elizabeth M., and J. David Cooper. "Density measurements in ice boreholes using neutron scattering." Journal of Glaciology 49, no. 167 (2003): 599–604. http://dx.doi.org/10.3189/172756503781830403.

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AbstractThis paper describes the use of a neutron probe to measure detailed stratigraphy in ice and snow. The Wallingford neutron probe, developed for measurement of soil moisture, consists of an annular radioactive source of fast neutrons around the centre of a cylindrical detector for slow (thermal) neutrons. In snow and ice, the fast neutrons lose energy by scattering from hydrogen atoms, and the number of slow neutrons arriving at the detector (the count rate) is related to the density of the medium. Calibration equations for count rate as a function of snow density and borehole diameter have been derived. Snow-density profiles from boreholes obtained using the probe show that, despite the smoothing produced by the neutron-scattering process, annual variations in density can be resolved. The potential contribution of the neutron probe to improvements in mass-balance monitoring is discussed.
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Roberts, Joyce A. "The Manuel Lujan Jr. Neutron Scattering Center." MRS Bulletin 22, no. 9 (September 1997): 42–46. http://dx.doi.org/10.1557/s0883769400033996.

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In October 1986, the neutron scattering facility at Los Alamos National Laboratory became a national user facility and a formal user program was initiated in 1988. In July 1989, this facility was dedicated as the Manuel Lujan Jr. Neutron Scattering Center (Lujan Center) in honor of the long-term Congress representative from New Mexico. The Lujan Center, part of the Los Alamos Neutron Science Center (LANSCE), is a pulsed spallation neutron source equipped with time-of-flight neutron-scattering spectrometers for condensed-matter research. Neutron scattering is a powerful technique for probing the microscopic structure of condensed matter. The energies and wavelengths of thermal neutrons closely match typical excitation energies and interatomic distances in solids and liquids. Because neutrons have no charge, they penetrate bulk samples of material to give precise information on the positions and motions of individual atoms. The magnetic moment of a neutron interacts with unpaired electrons, making neutrons ideal for probing microscopic magnetic properties. Because neutron-scattering cross sections do not vary monotonically with the atomic number of the scattering nucleus, neutrons and x-rays can provide complementary structural information. This technique is particularly effective for structural problems in polymer and biological studies because hydrogen and deuterium scatter neutrons strongly but with different cross sections.
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Dlougach, Eugenia, Mikhail Shlenskii, and Boris Kuteev. "Neutral Beams for Neutron Generation in Fusion Neutron Sources." Atoms 10, no. 4 (November 25, 2022): 143. http://dx.doi.org/10.3390/atoms10040143.

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Neutral beam injection is supposed to be the main source of high-energy particles, driving non-inductive current and generating primary neutrons in fusion neutron sources design based on tokamaks. Numerical simulation of high-energy particles’ thermalization in plasma and fusion neutron emission is calculated by novel dedicated software (NESTOR code). The neutral beam is reproduced statistically by up to 109 injected particles. The beam efficiency and contribution to primary neutron generation is shown to be dependent on the injection energy, input current, and plasma temperature profile. A beam-driven plasma operation scenario, specific for FNS design, enables the fusion rate and neutron generation in plasma volume to be controlled by the beam parameters; the resultant primary neutron yield can be efficiently boosted in plasma maintained at a relatively low temperature when compared to ‘pure’ fusion reactors. NESTOR results are applicable to high-precision nuclear and power balance estimations, neutron power loads distribution among tokamak components, tritium generation in hybrid reactors, and for many other tasks critical for FNS design.
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Pylypchuk, Ie V., V. O. Kovach, Anna V. Iatsyshyn, O. V. Farrakhov, V. N. Bliznyuk, and V. O. Kutsenko. "Immobilization of boronic acid derivative onto the magnetic Gd-containing composites." IOP Conference Series: Earth and Environmental Science 1049, no. 1 (June 1, 2022): 012014. http://dx.doi.org/10.1088/1755-1315/1049/1/012014.

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Abstract Aiming to develop new magnetic materials for neutron shielding applications, B- and Gd-containing magnetic nanoparticles were synthesized. Following bottom-up synthetic approach, core-shell Fe 3 O 4/Gd 2 O 3 nanocomposite particles were synthesized at the first stage. In the next stage, magnetic core-shell particles were modified with amino groups followed by grafting onto their surface of the boronic acid derivative. Such a multifunctional material, containing both boron (B) and gadolinium (Gd) atoms is a promising candidate for developing films and membranes, strongly interacting with neutrons. Due to the presence of boronic acids and bound to the indicator (Alizarin Red S), the material can induce color changes while immersed in sugar-containing solutions. Such a feature enables a possibility to estimate the number of boron atoms left after interaction with neutrons, thus allowing to check composite neutron-capture recourse.
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Liebschner, Dorothee, Pavel V. Afonine, Nigel W. Moriarty, Paul Langan, and Paul D. Adams. "Evaluation of models determined by neutron diffraction and proposed improvements to their validation and deposition." Acta Crystallographica Section D Structural Biology 74, no. 8 (July 24, 2018): 800–813. http://dx.doi.org/10.1107/s2059798318004588.

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The Protein Data Bank (PDB) contains a growing number of models that have been determined using neutron diffraction or a hybrid method that combines X-ray and neutron diffraction. The advantage of neutron diffraction experiments is that the positions of all atoms can be determined, including H atoms, which are hardly detectable by X-ray diffraction. This allows the determination of protonation states and the assignment of H atoms to water molecules. Because neutrons are scattered differently by hydrogen and its isotope deuterium, neutron diffraction in combination with H/D exchange can provide information on accessibility, dynamics and chemical lability. In this study, the deposited data, models and model-to-data fit for all PDB entries that used neutron diffraction as the source of experimental data have been analysed. In many cases, the reported R work and R free values were not reproducible. In such cases, the model and data files were analysed to identify the reasons for this mismatch. The issues responsible for the discrepancies are summarized and explained. The analysis unveiled limitations to the annotation, deposition and validation of models and data, and a lack of community-wide accepted standards for the description of neutron models and data, as well as deficiencies in current model refinement tools. Most of the issues identified concern the handling of H atoms. Since the primary use of neutron macromolecular crystallography is to locate and directly visualize H atoms, it is important to address these issues, so that the deposited neutron models allow the retrieval of the maximum amount of information with the smallest effort of manual intervention. A path forward to improving the annotation, validation and deposition of neutron models and hybrid X-ray and neutron models is suggested.
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Dissertations / Theses on the topic "Atomes neutres"

1

Schlosser, Nicolas. "Etude et réalisation de micro-pièges dipolaires optiques pour atomes neutres." Phd thesis, Université Paris Sud - Paris XI, 2001. http://tel.archives-ouvertes.fr/tel-00001195.

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Les atomes neutres piégés sont des candidats potentiels pour
l'implémentation de portes logiques quantiques. Dans ce contexte, cette étude
porte sur la réalisation d'un piège dipolaire optique de si petite taille qu'il
ne puisse contenir qu'un atome unique. Pour cela, il est nécessaire de
focaliser très fortement un laser à l'endroit où l'on désire capturer les
atomes. L'expérience s'articule donc autour d'un objectif de microscope de
grande ouverture numérique, entièrement conçu et réalisé au laboratoire. Cette
optique est utilisée pour faire focaliser un laser au centre d'un piège
magnéto-optique, réservoir d'atomes froids alimentant le piège dipolaire ainsi
créé.

Le dispositif d'observation des atomes piégés est basé sur le même objectif,
qui collecte, avec une grande efficacité, la fluorescence des atomes piégés et
en fait l'image sur une caméra CCD ou une photodiode à avalanche. La résolution
spatiale du dispositif utilisant la caméra permet d'obtenir une image des
atomes capturés, alors que l'on utilise la rapidité de la photodiode à
avalanche pour les études de la dynamique du piège avec une bonne résolution
temporelle.

Après une description détaillée de ce dispositif expérimental, nous montrons
qu'il est possible de réaliser des micro-pièges dipolaires optiques, de
quelques microns cube et contenant une dizaine d'atomes. L'étude de la
dynamique de chargement et de la durée de vie de ces pièges révèle également la
présence de processus de collisions à deux corps. Nous montrons ensuite qu'en
diminuant le taux de chargement il est possible d'observer, en temps réel, un
atome unique piégé pendant quelques secondes. Dans ce régime, un processus de
"blocage collisionnel" limite ce nombre d'atome à un. Pour finir, nous
décrirons la mise en place d'un double piège dipolaire, dans lequel on peut
piéger un atome unique dans chaque site. Ce dispositif ouvre la voie vers
l'étude de l'interaction entre atomes piégés individuellement.
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Beugnon, Jérôme. "Contrôle de l'état interne d'un atome unique piégé et expériences d'interférences à deux photons : vers l'information quantique avec des atomes neutres." Phd thesis, Université Paris Sud - Paris XI, 2007. http://tel.archives-ouvertes.fr/tel-00185446.

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Les atomes neutres sont de bons candidats pour la réalisation de protocoles d'information quantique. Cette thèse présente des expériences effectuées dans cette perspective sur des atomes individuels de rubidium piégés dans des pinces optiques de taille microscopique. Ces pinces sont obtenues en focalisant un faisceau laser sur une taille inférieure à un micromètre. Nous montrons que l'on peut contrôler l'état de chaque atome individuellement en faisant des transitions Raman à deux photons entre deux niveaux hyperfins de l'état fondamental. Nous observons des oscillations de Rabi entre ces deux niveaux à des fréquences pouvant atteindre plusieurs mégaHertz. Nous étudions aussi la cohérence de ce système par des expériences de franges de Ramsey et d'écho de spin. Des temps de cohérence de plusieurs dizaines de millisecondes sont mesurés. De plus, dans le but de manipuler des atomes dans un registre quantique, nous démontrons le déplacement d'une pince optique contenant un atome et le transfert de celui-ci d'une pince dans une autre sans perte de cohérence ni chauffage. Finalement, en vue de réaliser l'intrication conditionnelle de deux atomes, nous étudions l'émission de photons par ces atomes piégés. Nous montrons que ces atomes sont des sources de photons uniques déclenchables efficaces et nous décrivons l'observation d'interférences à deux photons entre deux photons uniques émis par deux atomes voisins indépendants. Ces interférences quantiques prouvent l'indiscernabilité des photons émis par chaque atome.
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Beugnon, Jérôme. "Contrôle de l'état interne d'un atome unique piégé et expériences d'interférences à deux photons : vers l'information quantique avec des atomes neutres." Phd thesis, Paris 11, 2007. http://www.theses.fr/2007PA112314.

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Les atomes neutres sont de bons candidats pour la réalisation de protocoles d'information quantique. Cette thèse présente des expériences effectuées dans cette perspective sur des atomes individuels de rubidium piégés dans des pinces optiques de taille microscopique. Ces pinces sont obtenues en focalisant un faisceau laser sur une taille inférieure à un micromètre. Nous montrons que l'on peut contrôler l'état de chaque atome individuellement en faisant des transitions Raman à deux photons entre deux niveaux hyperfins de l'état fondamental. Nous observons des oscillations de Rabi entre ces deux niveaux à des fréquences pouvant atteindre plusieurs mégaHertz. Nous étudions aussi la cohérence de ce système par des expériences de franges de Ramsey et d'écho de spin. Des temps de cohérence de plusieurs dizaines de millisecondes sont mesurés. De plus, dans le but de manipuler des atomes dans un registre quantique, nous démontrons le déplacement d'une pince optique contenant un atome et le transfert de celui-ci d'une pince dans une autre sans perte de cohérence ni chauffage. Finalement, en vue de réaliser l'intrication conditionnelle de deux atomes, nous étudions l'émission de photons par ces atomes piégés. Nous montrons que ces atomes sont des sources de photons uniques déclenchables efficaces et nous décrivons l'observation d'interférences à deux photons entre deux photons uniques émis par deux atomes voisins indépendants. Ces interférences quantiques prouvent l'indiscernabilité des photons émis par chaque atome.
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Kara, Abdelkader. "Contribution à l'étude expérimentale et théorique de la diffusion élastique d'atomes neutres par des surfaces périodiques et des surfaces avec des défauts isolés." Lille 1, 1985. http://www.theses.fr/1985LIL10031.

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L'étude expérimentale des surfaces de Cu par diffraction d'hélium à basse énergie permet de déterminer un potentiel d'interaction atome-surface. On peut déterminer la densité électronique en surface. Développement d'un formalisme de diffusion d'atomes neutres par les surfaces avec défauts isolés. La solution exacte est décrite sous forme de série de perturbation. En prenant une distribution aléatoire de défauts, les sections efficaces de diffusion calculées au 2ème ordre de perturbation pour des lacunes sur Cu(100) et Cu(110) et des atomes d'hydrogène adsorbés sur Cu(110) sont comparables a celles mesurées.
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Kissami, Abdelhamid. "Etude des sections efficaces d'excitation (desexcitation) et des profils des raies par des atomes neutres et ionises." Orléans, 1990. http://www.theses.fr/1990ORLE2030.

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Le travail entrepris a consiste en la realisation d'un programme numerique capable de calculer le profil des raies spectrales dans les plasmas, dans le cadre de l'approximation semi classique. Afin d'atteindre cet objectif plusieurs etapes ont ete franchies. La premiere consiste a calculer les sections efficaces d'excitation et desexcitation puis d'integrer l'ensemble sur une distribution maxwellienne dans l'espace des vitesses. La seconde etape a trait au calcul de la partie atomique du profil de raie (force de raie), qui est obtenue a partir d'une nouvelle technique fondee sur l'approximation coulombienne, dont le calcul de l'element de matrice radial est base sur des series recurrentes aisement calculables s'etendant a des domaines non hydrogenoides ainsi qu'aux niveaux de rydberg. La partie angulaire qui ne depend que du mode de couplage a ete programmee en utilisant les coefficients 6-j pour n'importe quel mode de couplage pur. En troisieme partie, la partie collisionnelle, du profil des raies est obtenue de maniere quasi-exacte par un calcul original des fonctions electroniques dipolaires et quadrupolaires. Cette methode s'avere etre une alternative bien superieure a toutes les formes empiriques, tel que le facteur de gaunt, utilisees habituellement. Les codes numeriques realises rendent possible le calcul des parametres d'elargissement d'un bon nombre de raies spectrales non tabulees jusqu'a present. Finalement ce logiciel permet un progres tres sensible, notamment par sa simplicite et sa vitesse d'execution par rapport a toutes les methodes de calcul utilisees actuellement et donne des resultats au moins aussi precis que les meilleurs calculs publies en bon accord avec la plupart des experiences fiables
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Jandura, Sven. "Optimized quantum gates for neutral atom quantum computers." Electronic Thesis or Diss., Strasbourg, 2024. http://www.theses.fr/2024STRAF027.

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Les atomes neutres sont récemment apparus comme une plate-forme compétitive pour l'informatique quantique. Le développement de portes quantiques intriquées de haute délité est la clé du succès de cette plateforme. Dans cette thèse, nous développons plusieurs protocoles nouveaux et optimisés pour l'implémentation de portes quantiques à deux et plusieurs qubits sur des atomes neutres. Nous introduisons la famille des protocoles temps-optimaux, qui implémentent une porte quantique donnée aussi rapidement que possible en appliquant une impulsion laser unique avec une phase dépendant du temps. Nous explorons également les protocoles de portes qui sont particulièrement robustes face à certaines sources d'erreurs expérimentales, et les portes qui sont optimisées pour leur utilisation dans un code de correction d'erreur quantique. En n, nous proposons deux nouveaux protocoles pour implémenter des portes multi-qubits non-locales sur des atomes neutres couplés à un mode de cavité commun qui peut être implémenté simplement par un pilotage classique de la cavité. Les résultats de cette thèse permettent d'obtenir des portes quantiques plus simples, de meilleure qualité et plus robustes sur des atomes neutres, et constituent une étape vers la réalisation de la vision d'un ordinateur quantique
Neutral atoms have recently emerged as a competitive platform for quantum computing. The development of high delity entangling quantum gates is a key to success of this platform. In this thesis, we develop several new and optimized protocols for the implementation of two- and multi-qubit quantum gates on neutral atoms. We introduce the family of time-optimal protocols, which implement a given quantum gate as fast as possible by applying a single laser pulse with a time-dependent phase. We also explore gate protocols which are particularly robust against certain experimental error sources, and gates which are optimized for their use in a quantum error correction code. Finally, we propose two new protocols to implement non-local multi-qubit gates on neutral atoms coupled to a common cavity mode which can be implemented simply by a classical drive of the cavity. The results of this thesis allow for simpler, higher quality, and more robust quantum gates on neutral atoms, and constitute a step towards realizing the vision of a quantum computer
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Loisel, Jean-Philippe. "Réalisation de sources lasers à l'état solide et observation du phénomène LIAD : application au développement d'une horloge optique à atomes neutres d'argent." Versailles-St Quentin en Yvelines, 2010. http://www.theses.fr/2010VERS0062.

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Les possibilités remarquables offertes par les techniques de refroidissement laser et de piégeage ont permis des avancées significatives dans le domaine des standards de fréquence à base d'atomes neutres. Parmi les différents systèmes permettant d'accéder à des valeurs de stabilité et précision élevés, l'atome d'argent est considéré comme l'un des candidats les plus prometteurs comme standard optique de fréquence. Cette thèse traite du développement d'une horloge basée sur des atomes neutres d'Ag. La transition 4d105s2 S1/2 > 4d95s2 2D5/2 dans l'Argent peut fournir une référence de fréquence pour les raisons suivantes : le niveau métastable 2D5/2, qui se relaxe par émission d'un photon quadripolaire électrique à 330. 5 nm, possède une durée de vie estimée à 0. 2 s, correspondant à une largeur de raie naturelle très faible de 0. 8 Hz. Il est par conséquent possible de bénéficier d'un long temps d'interaction pour le dispositif de fontaine atomique. De plus, cet état est accessible par une transition à 2 photons à 661. 2 nm, permettant d'éliminer l'effet Doppler du 1er ordre. Comme aspect technique important, la fréquence nécessaire pour la transition d'horloge et celle pour le refroidissement des atomes d'argent (raie D2 à 328 nm) peut être obtenue avec le même cristal de NdYLF (émission possible à 1322 nm/1312 nm). Ce travailde thèse détaille la réalisation de s sources nécessaires au refroidissement des atomes d'argent et à la transition d'horloge à l'aide d'un cristal de NdYLF pompé par diode et par deux étapes de doublage de fréquence intracavité. Par ailleurs, le phénomène LIAD y est présenté comme un compromis intéressant dans la conception d'une horloge atomique optique
The remarkable capabilities of laser cooling and trapping techniques for neutral atoms have led to great advances in the field of neutral atom-based frequency standards. Among the several atomic systems affording excellent prospects of high stability and accuracy in the optical region, the silver atom is regarded as one of the most promising candidates for an optical frequency standard. This thesis deals with the development of a clock based on neutral silver atoms. The Ag 4d105s2 S1/2 > 4d95s2 2D5/2 transition provides an attractive reference frequency for the following reasons : the 2D5/2 metastable level, which decays by emission of electric quadrupole radiation at 330. 5 nm, has an estimated lifetime of 0. 2 s, corresponding to an ultralow natural linewidth of only 0. 8 Hz. It’s therefore possible therefore to benefit from the long interaction time in an atomic fountain setup. Furthermore, the long-lived state is accessible with a two-photon transition at 661. 2 nm, providing a first-order Doppler-free interaction with atoms of all velocities. As an important technical aspect, the frequency needed to drive the clock transition and to cool the silver atoms (D2 line at 328 nm) can be provided by the same crystal Nd:YLF enable to generate both 1322 nm and 1312 nm. This work details especially the realization of the laser sources for both cooling silver atoms and driving the clock transition by diode-pumped Nd-YLF crystal and intracavity frequency doubling operation in two steps (second and fourth harmonic generation). In addition, the Lignt Induced Atomic Desorption (LIAD) phenomenon is described and observed as an interesting compromise in the case of an optical atomic clock conception
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8

Petitjean, Luc. "Étude théorique et expérimentale des collisions entre atomes de Rydberg et cibles neutres (atomique ou moléculaire) à énergie thermique : transferts résonnants d'énergie interne." Paris 11, 1985. http://www.theses.fr/1985PA112108.

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Cette thèse reporte une étude des propriétés collisionnelles des atomes de Rydberg avec des cibles neutres (atomique ou moléculaire). Ces collisions sont décrites dans le cadre de l'Approximation d'Impact (AI). Des méthodes permettant l'évaluation du facteur de forme de la transition atomique, étape clé dans le calcul d'une section efficace, sont proposées et discutées. Celles-ci autorisent de nombreuses confrontations avec les résultats expérimentaux. Les sections efficaces de dépeuplement total d'états de Rydberg du rubidium par des perturbateurs moléculaires (N2, CO, NH₃, ND₃) sont mesurées et comparées aux valeurs prédites par l'AI. L'influence des moments multipolaires de la molécule ainsi que celui d'autres paramètres physiques importants (le défaut d’énergie de la réaction, par exemple) sont clairement établies. Dans le cas des molécules dipolaires, le dépeuplement total est principalement dû au transfert quasi-résonnant d'énergie où l'énergie interne (atomique ou rotationnelle) perdue par l'un des partenaires de la collision est gagnée par l'autre. Enfin, notre approche théorique est étendue aux états moins excités et comparée à des résultats expérimentaux
This thesis reports a study of the collisional behavior of atomic Rydberg states with atomic and molecular targets. These collisions are described within the frame of the Impulse Approximation (IA). Methods for the evaluation of the atomic form factor, the key step in the derivation of the cross-section, are proposed and discussed allowing numerous comparisons with experimental data. The quenching cross-sections of high rubidium Rydberg states by molecular perturbers (N₂, CO, NH₃, ND₃) are measured and compared to IA predictions. The influence of the molecular multipole moment as well as of ether relevant physical parameters (energy balance of the reaction) are clearly stated. In the case of dipole molecules the total depopulation is mainly governed by near-resonant energy transfer where the internal energy (atomic or rotational) lest by one colliding partner is gained by the ether. Finally, our theoretical approach is tentatively extended to low-lying excited states and compared to experimental results
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Haas, Florian. "Creation of entangled states of a set of atoms in an optical cavity." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2014. http://tel.archives-ouvertes.fr/tel-00968861.

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In this thesis, we demonstrate the creation and characterization of multiparticle entangled states of neutral atoms with the help of a high finesse cavity. Our experimental setup consists of a fibre-based high finesse cavity above the surface of an atom chip. It allows us to prepare an ensemble of 87Rb atoms with well-defined atom number. The atoms are trapped in a single antinode of an intracavity standing wave dipole trap and are therefore all equally coupled to the cavity mode. We present a scheme based on a collective, quantum non-destructive (QND) measurement and conditional evolution to create symmetric entangled states and to analyze them at the single-particle level by directly measuring their Husimi Q function. We use this method to create and characterize W states of up to 41 atoms. From the tomography curve of the Q function, we reconstruct the symmetric part of the density matrix via different reconstruction techniques and obtain a fidelity of 0.42. Furthermore, we have devised an entanglement criterion which only relies on comparing two populations of the density matrix. We use it to infer the degree of multiparticle entanglement in our experimentally created states and find that the state with highest fidelity contains at least 13 entangled particles. In addition, we show preliminary results on experiments to count the atom number inside a cavity in the QND regime and to create entangled states via quantum Zeno dynamics.
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Dalyac, Constantin. "Quantum many-body dynamics for combinatorial optimisation and machine learning." Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS275.

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L'objectif de cette thèse est d'explorer et de qualifier l'utilisation de la dynamique quantique à N-corps pour résoudre des problèmes industriels difficiles et des tâches d'apprentissage automatique. En tant que collaboration entre des partenaires industriels et universitaires, cette thèse explore les capacités d'un dispositif à atome neutre pour résoudre des problèmes réels. Tout d'abord, nous examinons les problèmes d'optimisation combinatoire et montrons comment les atomes neutres peuvent naturellement encoder un célèbre problème d'optimisation combinatoire appelé le "Maximum Independent Set on Unit-Disk graphs". Ces problèmes apparaissent dans les défis industriels tels que le chargement intelligent des véhicules électriques. L'objectif est de comprendre pourquoi et comment on peut s'attendre à ce qu'une approche quantique résolve ce problème plus efficacement qu'une méthode classique. Les algorithmes que nous proposons sont testés sur un véritable à l'aide d'un ensemble de données provenant d'EDF, la compagnie française d'électricité. Nous explorons en outre l'utilisation d'atomes neutres en 3D pour résoudre des problèmes qui sont hors de portée des méthodes d'approximation classiques. Enfin, nous essayons d'améliorer notre intuition sur les types d'instances pour lesquelles une approche quantique peut (ou ne peut pas) donner de meilleurs résultats que les méthodes classiques. Dans la deuxième partie de cette thèse, nous explorons l'utilisation de la dynamique quantique dans le domaine de l'apprentissage automatique. En plus d'être une grande chaîne de mots à la mode, l'apprentissage automatique quantique (QML) a été de plus en plus étudié ces dernières années. Dans cette partie, nous proposons et mettons en œuvre un protocole quantique pour l'apprentissage automatique sur des ensembles de données de graphes, et nous montrons des résultats prometteurs en ce qui concerne la complexité de l'espace de caractéristiques associé. Enfin, nous explorons l'expressivité des modèles d'apprentissage automatique quantique et présentons des exemples où les méthodes classiques peuvent approximer efficacement les modèles d'apprentissage automatique quantique
The goal of this thesis is to explore and qualify the use of N-body quantum dynamics to Tsolve hard industrial problems and machine learning tasks. As a collaboration between industrial and academic partners, this thesis explores the capabilities of a neutral atom device in tackling real-world problems. First, we look at combinatorial optimisation problems and showcase how neutral atoms can naturally encode a famous combinatorial optimisation problem called the Maximum Independent Set on Unit-Disk graphs. These problems appear in industrial challenges such as Smart-Charging of electric vehicles. The goal is to understand why and how we can expect a quantum approach to solve this problem more efficiently than classical method and our proposed algorithms are tested on real hardware using a dataset from EDF, the French Electrical company. We furthermore explore the use of 3D neutral atoms to tackle problems that are out of reach of classical approximation methods. Finally, we try to improve our intuition on the types of instances for which a quantum approach can(not) yield better results than classical methods. In the second part of this thesis, we explore the use of quantum dynamics in the field of machine learning. In addition of being a great chain of buzzwords, Quantum Machine Learning (QML) has been increasingly investigated in the past years. In this part, we propose and implement a quantum protocol for machine learning on datasets of graphs, and show promising results regarding the complexity of the associated feature space. Finally, we explore the expressivity of quantum machine learning models and showcase examples where classical methods can efficiently approximate quantum machine learning models
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Books on the topic "Atomes neutres"

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1964-, Newbury Nathan, Wieman C. E, and American Association of Physics Teachers., eds. Trapping of neutral atoms. College Park, MD: American Association of Physics Teachers, 1998.

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P, Ozerov Ruslan, ed. Magnetic Neutron Diffraction. Boston, MA: Springer US, 1995.

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Smarandache, Florentin. Neutrosophic physics: More problems, more solutions, collection of papers. Hanko, Finland: North-European Scientific Publishers, 2010.

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Mohd Nor bin Md Yusuf. The interaction of fast neutral atoms with metal surfaces. [s.l.]: typescript, 1989.

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Janot, Christian, Winfried Petry, Dieter Richter, and Tasso Springer, eds. Atomic Transport and Defects in Metals by Neutron Scattering. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71007-0.

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DeLay, Glen Clark. Neutron placement with proton and positon. Lawndale, CA: DeLay's Printing, 2004.

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United States. National Aeronautics and Space Administration., ed. Surface conversion techniques for low energy neutral atom imagers: Final report. [Washington, DC: National Aeronautics and Space Administration, 1995.

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Agency, International Atomic Energy, ed. Neutron reflectometry: A probe for materials surfaces : proceedings of a technical meeting organized by the International Atomic Energy Agency and held in Vienna, 16-20 August 2004. Vienna: International Atomic Energy Agency, 2006.

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Civiš, Svatopluk, Ekaterina Zanozina, Adam Pastorek, Petr Kubelík, Martin Ferus, and Ashok Chilukoti. Atomic Emission Spectra of Neutral Noble Gases in the Infrared Spectral Range. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-47352-5.

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Conference on Neutron Scattering in the 'Nineties (1985 Jülich, Germany). Neutron scattering in the 'nineties: Proceedings of a conference ... organized by the International Atomic Energy Agency in cooperation with the Jülich Nuclear Research Centre and held in Jülich, 14-18 January 1985. Vienna: IAEA, 1985.

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Book chapters on the topic "Atomes neutres"

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Averyn, Viktar S. "Short Refresher of Radiobiology." In Nuclear and Radiological Emergencies in Animal Production Systems, Preparedness, Response and Recovery, 13–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-63021-1_2.

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AbstractThe atoms are built up of a nucleus, containing positive (protons) and neutral (neutrons) particles, surrounded by negative particles (electrons), circulating around the “atomic orbit”. The number of the protons in the nucleus is giving the atomic number of the element (usually labelled as “Z”), and the sum of the neutrons and protons in the nucleus is giving the atomic or mass number of the element (usually labelled as “A”). The number in the electrons in the atomic orbit is always equal to the number of protons in the nucleus. However, as the mass of the electrons is almost equal to zero, they do not influence the whole atomic mass.
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Raven, Will. "Isotope Shifts, Radioactive Decay, and the Nuclear Forces." In Atomic Physics for Everyone, 197–223. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-69507-0_10.

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AbstractIn this chapter, we explore the nucleus, focusing on how the number of neutrons in a nucleus influences transition frequencies and the stability of atoms. We begin by examining the effect of neutrons on transition frequencies, then shift into detailed discussions of the nuclear forces and principles governing atomic stability and radioactive decay. Various modes of radioactive decay, including neutron and proton emission, $$\alpha $$ α decay, spontaneous fission, $$\beta ^-$$ β − decay, $$\beta ^+$$ β + decay, and electron capture, are investigated, with an emphasis on the conditions under which each occurs. Additionally, we explore the nuclear shell model to understand the energetics behind different types of decays and the stability of isotopes.
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Michaud, Georges, Georges Alecian, and Jacques Richer. "Neutron Stars." In Atomic Diffusion in Stars, 259–70. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-19854-5_14.

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Radzig, Alexandre A., and Boris M. Smirnov. "Energetics of Neutral Atoms." In Springer Series in Chemical Physics, 87–120. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-82048-9_5.

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Vorburger, A., and P. Wurz. "Lunar Atmosphere, Energetic Neutral Atoms." In Encyclopedia of Lunar Science, 1–6. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-05546-6_221-1.

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Missimer, J. "Neutral Currents in Muonic Atoms." In Fundamental Interactions in Low-Energy Systems, 115–25. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4684-4967-9_7.

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Vorburger, A., and P. Wurz. "Lunar Atmosphere, Energetic Neutral Atoms." In Encyclopedia of Lunar Science, 462–67. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-319-14541-9_221.

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Radzig, Alexandre A., and Boris M. Smirnov. "Spectroscopic Characteristics of Neutral Atoms." In Springer Series in Chemical Physics, 147–257. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-82048-9_7.

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Aspect, Alain. "Laser Manipulation of Neutral Atoms." In NATO ASI Series, 193–206. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4899-1576-4_9.

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Metcalf, Harold J., and Peter van der Straten. "Magnetic Trapping of Neutral Atoms." In Graduate Texts in Contemporary Physics, 137–48. New York, NY: Springer New York, 1999. http://dx.doi.org/10.1007/978-1-4612-1470-0_10.

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Conference papers on the topic "Atomes neutres"

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Balewski, Jan, Milan Kornjača, Katherine Klymko, Siva Darbha, Mark R. Hirsbrunner, Pedro L. S. Lopes, Fangli Liu, and Daan Camps. "Engineering Quantum States with Neutral Atoms." In 2024 IEEE International Conference on Quantum Computing and Engineering (QCE), 1221–27. IEEE, 2024. https://doi.org/10.1109/qce60285.2024.00144.

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Bergeman, Thomas, and Harold Metcalf. "Magnetic trapping of neutral atoms." In International Laser Science Conference. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/ils.1986.wf6.

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Magnetic trapping of laser-cooled neutral atoms has been demonstrated at NBS and is progressing in other laboratories. Confinement of any object requires exchanging kinetic for potential energy, and for neutral atoms, this necessarily derives from shifts of internal energy levels. This is implemented through the force experienced by the atomic magnetic moment in a carefully designed, highly inhomogeneous field. Since magnetic fields of convenient strength can shift atomic energy levels by only a few gigahertz (temperature ≌ 0.1 K), neutral atom traps are very shallow and must be loaded with very cold atoms. We present some motivations for using magnetic traps and then discuss the constraints and optimal configurations of various arrangements. For example, no trap can be isotropic. Next we discuss both the classical and quantum mechanical motions of trapped atoms. These motions are important for at least two reasons: First, several schemes under study for further cooling depend on knowing the position and velocity of the atoms, as well as the vector field at each point along the orbit. Second, magnetic traps depend on the atomic moment remaining aligned with the field as the atom orbits in the trap, and this precludes rapid motion through a low-field region.
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Chu, Steven, Mark Kasevich, Kathryn Moler, Erling Riis, and David Weiss. "Future of neutral atom clocks." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.wh1.

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The measurement on energy levels suitable for time standards can be made more precise with the use of neutral atom manipulation techniques. We have created a fountain of atoms where the measurement time of atoms in ballistic free-fall can be on the order of a fraction of a second. With these long measurement times, the linewidth of the transition between the ground state hyperfine transition of sodium was measured to be 2 Hz. Transitions in the optical frequency range could then have Q's of 1014 to 1015. In addition to creating high Q resonances, it is desirable to have a continuous, high density fountain of atoms. Towards this end, we have constructed an "atomic funnel" capable of creating a cold, high flux stream of atoms suitable for injection into a continuous atomic fountain. In the first embodiment of the funnel, the brightness of the atomic beam (defined as the number of atoms per second/( ΔvxΔvyΔvz) was increased by a factor of 3 × 103. With more recent improvements for both funneling more atoms from the hot atomic beam and better use of polarization gradient cooling to launch the atoms, we will describe how to improve the brightness enhancement by another four orders of magnitude.
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Oates, Chris, Zeb Barber, Jason Stalnaker, Chad Hoyt, Yann Le Coq, and Leo Hollberg. "Optical Atomic Clocks Based Upon Neutral Atoms." In Laser Science. Washington, D.C.: OSA, 2007. http://dx.doi.org/10.1364/ls.2007.ltuh3.

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Ketterle, Wolfgang. "Recent Advances in Bose-Einstein Condensation." In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/cleo_europe.1998.plen1.

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The observation of Bose-Einstein condensation (BEC) in dilute atomic gases was the realization of many long-standing goals: (1) to cool neutral atoms into the ground state of the system, thus exerting ultimate control over the motion and position of atoms limited only by Heisenberg's uncertainty relation; (2) to generate a coherent sample of atoms all occupying the same quantum state (this was subsequently used to realize an atom laser, a device which generates coherent matter waves); and (3) to create a quantum fluid with properties quite different from the quantum liquids He-3 and He-4. This provides a test-ground for many-body theories of the dilute Bose gas which were developed many decades ago, but never tested experimentally.
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Ido, T., M. M. Boyd, A. D. Ludlow, T. Zelevinsky, S. Blatt, S. M. Foreman, M. Notcutt, and J. Ye. "Optical atomic clocks based on ultracold neutral strontium atoms." In International Quantum Electronics Conference, 2005. IEEE, 2005. http://dx.doi.org/10.1109/iqec.2005.1561161.

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Phillips, William D. "Laser cooling, stopping, and magnetic trapping of neutral atoms." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.wv3.

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A thermal atomic Na beam is opposed by a resonantly tuned laser beam. The radiation pressure decelerates and compresses the thermal velocity distribution, bringing the average velocity to zero and reducing the width from ~1000 m/s to a few tens of m/s or less.1 The density of stopped atoms is > 106/cm3 within a bandwidth of a few m/ s. These densities and velocities are suitable for trapping by a number of proposed optical and magnetic traps. Using these stopped atoms, we have demonstrated the first electromagnetic trapping of neutral atoms. The trap, a magnetic quadrupole formed by two separated, coaxial, opposed current loops, confines the atoms by virtue of the force exerted on the Na magnetic dipole moment by the inhomogeneous magnetic field. The time constant for exponential decay of the atomic population in the trap is 0.83(7) s and is limited mainly by collisions with fast background gas atoms. The maximum velocity of atoms contained in the trap is 3.5 m/s, corresponding to a maximum energy of 17 mK.
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Maruyama, Ippei, Osamu Kontani, Shohei Sawada, Osamu Sato, Go Igarashi, and Masayuki Takizawa. "Evaluation of Irradiation Effects on Concrete Structure: Background and Preparation of Neutron Irradiation Test." In ASME 2013 Power Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/power2013-98114.

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Methods for assessing the soundness of concrete exposed to irradiation are being developed within the framework of a project of the Nuclear Regulation Authority (NRA) “Japan Ageing Management Program for System Safety”. This paper presents the background of this project and recent research works. The major reason for deterioration of concrete under irradiation conditions is expansion of aggregate due to neutron and gamma-ray irradiation. Dislocation of atoms in covalent structures of aggregate minerals, and resultant lattice constant change and alteration to amorphous phase are produced by fast neutrons. In addition, through electronic exertion, some energy deposition is accumulated as permanent distortion/strain in atomic structures. Other effects are also summarized. We plan to conduct a neutron irradiation test from May 2013. In selecting mix proportions and concrete components for the irradiation test program, sample size as a function of capsule size and gamma-heating, cement type, and aggregate size and type are determined based on preliminary experiments.
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Holmgren, D. E., and D. F. Prelewitz. "Sodium core-excited fluorescence enhancement by charge transfer." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.thpo19.

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We have demonstrated a technique which enhances emission lines of core-excited Na transitions occurring in a hollow-cathode discharge. The technique should apply to other alkali atoms and could help in identifying the core-excited visible spectra of heavier alkali atoms. In our experiment, stored population is produced by the discharge in the Na-ion metastable level 2p53s J = 2. A pulsed dye laser is used to transfer this population to a higher ion level of the 2p53p configuration. Core-excited neutral atoms are subsequently produced by an exothermic charge transfer from ground neutrals to the enhanced parent 2p53p ion population. We observe enhanced fluorescence (2 to 3 times above background levels) from neutral 2p53s3d, 2p53s4s, and possibly 2p53p2 configurations when the metastable ion population is transferred to higher ion levels.
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Yanli, Xiong, Qiu Xiaopeng, Liu Shuhuan, Li Zhuoqi, Liu Shuangying, Ma Yong, Song Ci, and Han Ning. "Simulation and Analysis of 4H-SiC-Based PiN Fast Neutron Detector With Polyethylene Converter Using Geant4." In 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-92268.

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Abstract When detecting fast neutrons, generally select materials with high hydrogen content, such as polyethylene and lithium hydride. It’s known that polyethylene is widely used and has high detect efficiency. Therefore, this paper uses Geant4 software to simulate 4H-SiC-based PiN fast neutron detector with polyethylene converter of varies thickness. With the increase of converter thickness, the conversion efficiency of 1–14MeV monoenergetic fast neutron will first increase and then decrease. By analysing the trend of conversion efficiency, the thickness is determined as 1000um. Then, the 1MeV, 2MeV, 4MeV and 8MeV monoenergetic neutrons and typical fats neutron source: Am-Be neutron source are simulated under the thickness of 1000um convertor, the particle types and energy distribution to the sensitive volume and the energy deposition of particles in the sensitive region are also obtained. Through the analysis of recoil proton energy spectrum, the relationship between incident neutron energy and recoil proton energy are studied. Also, through the analysis of PKA (primary knocked-out atoms) energy spectrum, we found that the main reactions in epi-layer are 28Si(n,n’) 28Si, 12C(n,n’) 12C, 28Si(n,α) 25Mg, 28Si(n,p) 28Al, etc. It is found that heavy ions such as C and Si produced by neutrons in sensitive volume account for a large proportion. The above research finally helps to investigate the deposit energy in the epi-layer.
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Reports on the topic "Atomes neutres"

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Ків, Арнольд Юхимович, Володимир Миколайович Соловйов, and Sergey A. Tomilin. Formation of Si precipitates іn neutron irradiated Al. Видавничий відділ КДПУ, 2001. http://dx.doi.org/10.31812/0564/1027.

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Transmutation reactions are the unique way to get a large concentration of Silicon atoms in Aluminum lattice, and just in substitutional positions. Appearing Silicon atoms in Aluminum lattice instead of Aluminum atoms leads to arising of mechanical stresses. This factor is the keystone of the model, which allows to explain the main peculiarities of Si precipitate creation in Aluminum irradiated by thermal neutrons. First, we shall describe the qualitative peculiarities of the model. Then we shall perform some quantitative estimates. At last the model will be discussed and compared with experimental data.
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Holden, T., J. Root, and R. Hosbons. CWI1988-Andi-12 Neutron Diffraction of Axial Residual Strains in the Vicinity of a Girth Weld. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), April 1988. http://dx.doi.org/10.55274/r0011390.

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Recent research has shown that neutron diffraction is a practical non-destructive method for determining residual strains in the vicinity of a girth weld in line pipe. The basis of the technique is that the distance between planes of atoms is used as a miniature, directional, internal strain gauge, just as for X-ray measurements. However, the penetration of neutrons into metals ls from 1000 to 10,000 times greater than that of X-rays, so that measurements may easily be made throughout the thickness of steel pipe including the region of the weld itself. The purpose of the present measurements was to characterize the axial residual strains remaining in linepipe after two pieces had been joined with a girth weld. This report summarizes the measurements of the axial residual strains in each of two pipes of thickness 11 and 16 mm at the 6:00, 1:30 and 10:00 positions.
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Hill, C. Summary Report of the Third Research Coordination Meeting on Data for Atomic Processes of Neutral Beams in Fusion Plasma. IAEA Nuclear Data Section, June 2022. http://dx.doi.org/10.61092/iaea.twqe-92hz.

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10 experts in the field of atomic collisional physics and neutral beam modelling for magnetic confinement fusion devices, together with IAEA Staff met online from 24 – 26 November 2021 for the Third Research Coordination Meeting of the IAEA Coordinated Research Project (CRP) F43023: Data for Atomic Processes of Neutral Beams in Fusion Plasma. They described progress since the previous project meeting in February 2019, discussed open issues and reviewed the coordinated research and code comparison activities conducted as part of the CRP. The proceedings of the meeting are summarized in this report.
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Hill, Christian. Data for Atomic Processes of Neutral Beams in Fusion Plasma. IAEA Nuclear Data Section, February 2019. http://dx.doi.org/10.61092/iaea.19hv-wzn5.

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12 experts in the field of atomic collisional physics and neutral beam modelling for magnetic confinement fusion devices, together with IAEA staff met at IAEA Headquarters 19 – 21 February 2019 for the Second Research Coordination Meeting of an IAEA Coordinated Research Project on Data for Atomic Processes of Neutral Beams in Fusion Plasma. They described progress with their research since the previous project meeting in June 2017, discussed open issues and made plans for continued coordinated research and code comparison during the remaining years of the project. The proceedings of the meeting are summarized in this report.
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Pritchard, David E., and Wolfgang Ketterle. Experiments with Trapped Neutral Atoms. Fort Belvoir, VA: Defense Technical Information Center, March 1996. http://dx.doi.org/10.21236/ada306690.

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Ketterle, Wolfgang. Experiments With Trapped Neutral Atoms. Fort Belvoir, VA: Defense Technical Information Center, January 2010. http://dx.doi.org/10.21236/ada514076.

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Ketterle, Wolfgang. Experiments with Trapped Neutral Atoms. Fort Belvoir, VA: Defense Technical Information Center, August 2000. http://dx.doi.org/10.21236/ada381427.

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Saffman, Mark, and Thad Walker. Quantum Logic With Cold Neutral Atoms. Fort Belvoir, VA: Defense Technical Information Center, August 2006. http://dx.doi.org/10.21236/ada454801.

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Lee, Jongmin, Michael J. Martin, Yuan-Yu Jau, Ivan H. Deutsch, and Grant W. Biedermann. A new approach to entangling neutral atoms. Office of Scientific and Technical Information (OSTI), November 2016. http://dx.doi.org/10.2172/1333520.

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Phillips, William D. Laser Cooling and Trapping of Neutral Atoms. Fort Belvoir, VA: Defense Technical Information Center, July 1992. http://dx.doi.org/10.21236/ada253537.

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