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Showing 1 to 20 of 27 for “"ATOMIC BEAM"”.
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Atomic beam techniques in a rubidium vapour cell
… a study on the realisation of a usable rubidium atomic beam inside a sealed vapour cell. A velocity selective optical pumping scheme was implemented to enable the detection of atoms of a particular velocity class travelling between two separated laser beams. This represents a new spectroscopic …
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Investigation of Gas-Surface Dynamics Using an Ar Atomic Beam and Functionalized Self-Assembled Monolayers
… gas species. Our research employs molecular beam techniques and well-characterized surfaces to study these processes. The goal of this study is to better understand how the physical and chemical nature of the surface interface influences energy transfer dynamics in gas-surface collisions. An …
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The force on an atom moving in an intense standing wave
… the transverse velocities of atoms in a thermal beam. When the standing wave is tuned above resonance the atomic beam is collimated and has an increased intensity at the center of the beam. Below resonance, the SW anti-collimates the atomic beam, reducing the central intensity. These effects are …
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Laserless slow atom source for loading atom traps
… to selectively remove the fast atoms from an atomic beam and to guide the remaining slow atoms into a trapping region. The permanent magnets establish a quadrupole field which extends along the axis of a bent vacuum nipple. A threshold velocity is set by the radius of curvature of the bent …
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Measurement of second-order coherence in the microlaser
… a new velocity selection scheme for the barium atomic beam and a new simple multi-stop time-to- digital converter (MSTDC). Using two .dye lasers, a narrow velocity ground-state barium atomic beam is prepared. It has a velocity width of about 10% and a height of more than 50% of the original …
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Apparatus for the lifetime measurement of Samarium excited states
… ... A new method for the detection of the atomic beam of some materials is presented.
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Πολυφωτονική φασματοσκοπία του Sr-αυτοϊονιζόμενες καταστάσεις με J=3 και διπλός ιονισμός
Focusing one or two dye laser beams in a Sr atomic beam and using a TOF mass spectrometer. A) We have recorded energy level positions and autoionization widths of the odd pavity J=3 states of Sr, in the energy range. Between the 5S1/2 and 4D3/2, 5/2 ionization limits. The analysis of the spectra …
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Spinabhängige Asymmetriefunktionen in der elastischen und inelastischen Elektron-Cäsium-Streuung bei mittleren Energien
… as theoretically, for many years. In a crossed-beam arrangement a polarized electron beam from a strained GaAs crystal is intersected with a polarized Cs atomic beam to measure the angular dependences of the spin-asymmetries A1, A2 and Ann as well as the relative differential cross section at …
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Cross sections for photoionization of the 6²P-fine structure levels of cesium
… levels have been measured using a triple crossed-beam apparatus. Two photon beams, one for excitation and one for ionization, impinge upon an atomic beam and produce ions at the point of intersection. The relative cross section is determined from a knowledge of the ion count rate and the relative …
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Optical manipulation of helium(2(3)S) atoms with a diode laser
… has been used to efficiently spin polarize an atomic beam of He(2$\sp3$S) metastable atoms by optical pumping on the $\rm 2\sp3S\sb1\rightarrow2\sp3P\sb1$ (D1) transition. The diode laser is an InGaAs/GaAs strained multiquantum well with a distributed Bragg reflector to insure single …
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Photoionization of laser excited barium
… theory. The experiments were performed using an atomic beam apparatus and two lasers. One laser beam, of fixed wavelength, excited ground state barium atoms to the 6s6p ¹P state while the other, of variable wavelength, was used to ionize these atoms. Several different combinations of …
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Analysis of scattered protons in deuteron electrodisintegration with a polarized electron beam and an internal polarized target
… In particular, the tensor asymmetry, Ad, and beam-vector asymmetry, Al, from deuteron electrodisintegration, ... , are sensitive to the existence of a tensor component in the NN interaction. The Bates Large Acceptance Spectrometer Toroid (BLAST) provides a unique opportunity to measure …
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Theory Advances in High-Precision Two-Photon Spectroscopy
… model which can be used for the analysis of atomic beam experiments. Dynamic polarizabilities of relevant S and D states, quantifying the dynamic Stark shift, and transition matrix elements among these states are calculated, taking into account leading-order relativistic, radiative and …
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On Quantum Reflection and The Casimir Effect : Application to atom-surface scattering
… analysis of experimental data obtained with the Atomic Beam Spin Echo (ABSE) spectrometer by scattering 3He from a strongly disordered alpha-quartz dielectric surface and from an atomically rough gold surface under grazing incidence. The data are interpreted in terms of the quantum reflection …
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Helium Atom Scattering from Chiral Structures
… to motivate the study of chiral surfaces using atomic beam techniques. The importance of chirality is discussed in chapter 1, along with the significant role played by surfaces in the creation of chiral media required for biologically and industrially relevant enantioselective reactions. The key …
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Development of a laser ionization test bench for radioactive ion beams
… it can play in the production of radioactive ion beams. The theory of the production of radioactive ion beams and resonant laser ionization using different techniques will be discussed. Furthermore, the Isotope Separation On-Line method will be comprehensively discussed and the requirements needed …
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Measuring atomic properties with an atom interferometer
Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths, one of which travels through an interaction region. The paths are recombined, and the interference pattern exhibits a phase shift …
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⁸⁷Rubidium Bose-Einstein condensates : machine construction and quantum Zeno experiments
… 87Rb is described in detail. A high flux thermal atomic beam is decelerated by a Zeeman slower and is then captured and cooled in a magneto-optical trap. The atoms are then transfered into a cloverleaf style Ioffe-Pritchard magnetic trap and cooled to quantum degeneracy with radio frequency …
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Measurement of the electric form factor of the neutron at low momentum transfers using a vector polarized deuterium gas target at BLAST
… measurements require highly polarized electron beams and either a vector polarized neutron target (typically ²H) or else a neutron final state polarimeter. The Bates Large Acceptance Spectrometer Toroid (BLAST) provides a unique opportunity to measure! the shape of the neutron electric form …
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Exotic Species of Hydrogen
… and theoretical investigations of the triatomic molecule H3 and the negative ion of Hydrogen H-. These 'exotic' systems of Hydrogen are known to have a rather instable character due to their strong internal coupling and correlation phenomena. Their astrophysical significance and their role …
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