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The article discusses three jazz albums: "Embracing Dawn" by Marius Neset, "Possession" by Asha Parkinson, and "Embracing Dawn" by Christian Sands. The albums feature a combination of classical and jazz musicians, with compositions that are mostly written rather than improvised. The article praises the albums for their thoughtful conception and interesting addition to the modern chamber music and jazz repertoire. It also highlights the skills of the artists in arranging and composing, as well as their ability to create a narrative through the sequence of tracks. [Extracted from the article]

This report presents the time filtered BDF- k (FiBDF- k) methods up to fourth-order time accuracy for the molecular beam epitaxial equation with no-slope selection. The new (k + 1) -order methods are developed by introducing an inexpensive post-filtering step to the variable-step BDF- k (k = 1 , 2 , 3) methods. We show that the FiBDF- k methods are uniquely solvable and volume conservative. Some novel discrete gradient structures of the FiBDF- k formulas are derived such that we can build up the discrete energy dissipation laws for the associated time-steppings. Numerical examples are included to show the mesh-robustness and effectiveness of the variable-step methods especially in the long-time simulations. • High-order variable-step time filtered BDF-k (FiBDF-k) methods. • Novel discrete gradient structures of the FiBDF-k formulas. • Mesh-robustly stability and adaptive time-stepping strategy. [ABSTRACT FROM AUTHOR]

Focuses on the applications of radiation pressure. Acceleration of small neutral particles to high velocity; Atomic beams; Molecular beams.

The article focuses on chemical accelerators. The first successful molecular-beam studies of a chemical reaction were made by Sheldon Datz and Ellison H. Taylor of the Oak Ridge National Laboratory with the use of the apparatus in 1955. One problem encountered in the use of chemical accelerators is the absence of a simple method in detecting neutral atoms and molecules. A dipole accelerator to accelerate molecules is currently being built by Lennard Wharton of the University of Chicago in Illinois.

The article discusses the impact of the development of masers, lasers and atomic clocks on the evolution of modern physics. The three necessary elements of modern molecular beams are source of molecules with an aperture through which the molecules can escape into a vacuum, the collimating aperture and a method for detecting the effects of various influences on the beam.

Molecular Beam Epitaxy (MBE) is a high-vacuum technique with atomic-layer control and precision. It is based on the chemical reaction of the atoms, molecules, or atomic clusters vaporized from the specific evaporation sources on the substrates. The molecular beam defines a unidirectional ballistic flow of atoms and/or molecules without any collisions amongst. In the late 1960s, MBE was initially developed for the growth of GaAs and (Al, Ga)As systems[1,2] due to the unprecedented capabilities and then was applied to study other material systems. MBE growth is conventionally performed in vacuum and ultra-high vacuum (UHV) (10-8–10-12 mbar) conditions. [ABSTRACT FROM AUTHOR]

An implicit–explicit linear BDF2 scheme with variable steps is proposed for the molecular beam epitaxial model without slope selection. The fourth-order surface diffusion term is treated implicitly and the nonlinear term is approximated by a second order explicit extrapolation. A new type regularization term A τ 2 Δ h 2 D 2 ϕ n ( D 2 ϕ n represents the variable-step BDF2 formula) is designed to ensure unconditional energy stability in long-time simulations. Under the time-step ratio constraint 0 < τ k / τ k − 1 < 4. 864 , the linear BDF2 method preserves the modified discrete energy dissipation law unconditionally if a proper large constant A is chosen. Furthermore, with the help of discrete orthogonal convolution kernels and the corresponding convolution Young inequalities, the L 2 norm stability and convergence analysis of the linear BDF2 scheme for the MBE model are established. Numerical examples are presented to demonstrate the accuracy and efficiency of the proposed scheme. [ABSTRACT FROM AUTHOR]

We propose laser-based methods for the production of nuclear spin hyperpolarized molecules. Following pulsed, coherent excitation from ground-state molecules in a molecular beam to specific rotational |J mj) states, the resulting hyperfine polarization beating produces desirable nuclear spin m¡ population distributions and mj -- mj correlations at specific later times. At this point, selective dissociation can be used to remove undesired spin states, or a strong magnetic field can be applied, which later can be removed adiabatically to transfer the population-enhanced nuclear spin configurations to the desired nuclear spin state. Finally, the polarization beating is stopped, and the molecules are stored by cryogenic trapping. We show how these methods can be used to produce the long-lived singlet state of l5N2O and ortho H2O, which have been proposed as magnetic tracers. We discuss how large production rates between 1 and 100 jumol/s with singlet-state populations between 35% and 100% can be achieved. [ABSTRACT FROM AUTHOR]

We present a formalism to calculate phase-space acceptance in a Zeeman decelerator. Using parameters closely mimicking previous Zeeman deceleration experiments, this approach reveals a velocity dependence of the phase stability which we ascribe to the finite rise and fall times of the current pulses that generate the magnetic fields inside the deceleration coils. It is shown that changing the current switch-off times (characterized by the reduced position of the synchronous particle K0) as the sequence progresses, so as to maintain a constant mean acceleration per pulse, can lead to a constant phase stability and hence a beam with well-defined characteristics. We also find that the time overlap between fields of adjacent coils has an influence on the phase-space acceptance. Previous theoretical and experimental results [A. W. Wiederkehr et al., Phys. Rev. A 82, 043428 (2010); J. Chem. Phys. 135, 214202 (2011).] suggested unfilled regions in phase space that influence particle transmission through the decelerator. Our model provides a means to directly identify the origin of these effects due to coupling between longitudinal and transverse dynamics. Since optimum phase stability is restricted to a rather small parameter range in terms of the reduced position of the synchronous particle K0, only a limited range of final velocities can be attained using a given number of coils. We evaluate phase stability for different Zeeman deceleration sequences, and by comparison with numerical three-dimensional particle-trajectory simulations, we demonstrate that our model provides a valuable tool to find optimum parameter sets for improved Zeeman deceleration schemes. An acceleration-deceleration scheme is shown to be a useful approach to generating beams with well-defined properties for variable-energy collision experiments. More generally, the model provides significant physical insights that are applicable to other types of particle decelerators with finite rise and fall time fields. [ABSTRACT FROM AUTHOR]

Advanced pulsed cryogenic molecular-beam electric deflection methods involving position-sensitive mass spectrometry and 7.87-eV ionizing radiation were used to measure the polarizabilities of more than half of the metallic elements in the Periodic Table. Concurrent Stern-Gerlach deflection measurements verified the ground-state condition of the measured atoms. Comparison with state-of-the-art calculations exposes significant systematic and isolated discrepancies throughout the Periodic Table. [ABSTRACT FROM AUTHOR]

Ultracold molecular gases are promising as an avenue to rich many-body physics, quantum chemistry, quantum information, and precision measurements. This richness, which flows from the complex internal structure of molecules, makes the creation of ultracold molecular gases using traditional methods (laser plus evaporative cooling) a challenge, in particular due to the spontaneous decay of molecules into dark states. We propose a way to circumvent this key bottleneck using an all-optical method for decelerating molecules using stimulated absorption and emission with a single ultrafast laser. We further describe single-photon cooling of the decelerating molecules that exploits their high dark state pumping rates, turning the principal obstacle to molecular laser cooling into an advantage. Cooling and deceleration may be applied simultaneously and continuously to load molecules into a trap. We discuss implementation details including multilevel numerical simulations of strontium monohydride. These techniques are applicable to a large number of molecular species and atoms with the only requirement being an electric dipole transition that can be accessed with an ultrafast laser. [ABSTRACT FROM AUTHOR]

Heavy diatomic molecules have been identified as good candidates for use in electron electric dipole moment (eEDM) searches. Suitable molecular species can be produced in pulsed beams, but with a total flux and/or temporal evolution that varies significantly from pulse to pulse. These variations can degrade the experimental sensitivity to changes in the spin precession phase of an electrically polarized state, which is the observable of interest for an eEDM measurement. We present two methods for measurement of the phase that provide immunity to beam temporal variations, and make it possible to reach shot-noise-limited sensitivity. Each method employs rapid projection of the spin state onto both components of an orthonormal basis. We demonstrate both methods using the eEDM-sensitive H³Δ1 state of thorium monoxide, and use one of them to measure the magnetic moment of this state with increased accuracy relative to previous determinations. [ABSTRACT FROM AUTHOR]

We examine two approaches for significantly extending the velocity range of the optical bichromatic force (BCF), to make it useful for laser deceleration of atomic and molecular beams. First, we present experimental results and calculations for BCF deceleration of metastable helium using very large BCF detunings and discuss the limitations of this approach. We consider in detail the constraints, both inherent and practical, that set the usable upper limit of the BCF. We then show that a more promising approach is to utilize a BCF profile with a relatively small velocity range in conjunction with chirped Doppler shifts, to keep the force resonant with the atoms as they are slowed. In an initial experimental test of this chirped BCF method, helium atoms are slowed by ≲370 m/s using a BCF profile with a velocity width of ≲125 m/s. Straightforward scaling of the present results indicates that a decelerator for He" capable of loading a magneto-optical trap can yield a brightness comparable to a much larger Zeeman slower. [ABSTRACT FROM AUTHOR]

We demonstrate the spatial separation of the prototypical indole(H20) clusters from the various species present in the supersonic expansion of mixtures of indole and water. The major molecular constituents of the resulting molecular beam are H20, indole, indole(H20), and indole(H20)2. It is a priori not clear whether such floppy systems are amenable to strong manipulation using electric fields. Here, we have exploited the cold supersonic molecular beam and the electrostatic deflector to separate indole(H20) from the other molecular species as well as the helium seed gas. The experimental results are quantitatively explained by trajectory simulations, which also demonstrate that the quantum-state selectivity of the process leads to samples of indole(H20) in low-lying rotational states. The prepared clean samples of indole(H20) are ideally suited for investigations of the stereodynamics of this complex system, including time-resolved half-collision and diffraction experiments of fixed-in-space clusters. Our findings clearly demonstrate that the hydrogen bonded indole(H20) complex behaves as a rigid molecule under our experimental conditions and that it can be strongly deflected [ABSTRACT FROM AUTHOR]

We show that the multiplicative product of a molecular-beam excitation spectrum and an ultracold-molecule excitation spectrum, with a frequency offset appropriate to the initial ultracold-molecule level, provides the relative rate of stimulated Raman transfer (SRT) from a given high rovibrational level to the lowest rovibronic level, i.e., the vn = 0,jn = 0 level of the ground electronic state for photoassociated (and magnetoassociated) ultracold molecules. This product spectrum clearly indicates the optimal pathways for SRT, even when the two component spectra are completely unassigned. We illustrate this specifically for the case of KRb. [ABSTRACT FROM AUTHOR]

We demonstrate experimentally the guiding of cold and slow ND3 molecules along a thin charged wire over a distance of ~0.34 m through an entire molecular beam apparatus. Trajectory simulations confirm that both linear and quadratic high-field-seeking Stark states can be efficiently guided from the beam source up to the detector. A density enhancement up to a factor 7 is reached for beams with velocities ranging down to ~ 150 m/s generated by the rotating nozzle technique. [ABSTRACT FROM AUTHOR]

Supersonic-jet luminescence spectroscopy was applied to study vibronic transitions in icosahedral N2 and Ar-N2 clusters having from 100 to 400 particles per cluster. In the case of mixed Ar-N2 clusters, the w 1Δu→ X1Σg+ transitions were observed to occur in single N2 molecules in an Ar environment, in very much the same way as in Ar-N2 bulk samples. In N2 clusters, however, a band series was detected which, to our knowledge, was never observed earlier. In the spectra of Ar-N2 clusters, this series coexisted with the "bulk" w 1Δu→ X1Σg+ transitions. Our analysis demonstrated that the series should be assigned to emission of van der Waals (N2)2 dimers from inside clusters. Earlier, such dimers were only observed in molecular beams and gaseous nitrogen; this paper reports their observation in the solid phase of nitrogen. Our results can be of interest from the viewpoint of producing polymeric nitrogen since (N2)2 dimers can be considered to be a starting species for its synthesis. [ABSTRACT FROM AUTHOR]

We report recent U.S. R&D progress on neutrino factory studies since last International Neutrino Factory Workshop. Our R&D programs cover wide range of research areas which include targetry, muon cooling hardware development, acceleration and simulations of intense muon beams. These programs are integrated well with international R&D programs for neutrino factory studies and the International Muon Ionization Experiment (MICE) at Rutherford Appleton Laboratory (RAL), U.K. [Copyright &y& Elsevier]

This report reviews the status of detector studies for future neutrino oscillation experiments at Super-Beams, β-Beams or ν-Factories. The following techniques are considered: Low-Z Tracking Calorimetry, Water Čerenkov, Liquid Argon Time Projection Chamber, Magnetised Iron Calorimetry and Emulsion Cloud Chamber. For each technique, the attention is focused on the main issues in R&D and detector design. [Copyright &y& Elsevier]

Looks at some fascinating developments in precisely guiding chemical reactions at the microscopic, molecular level. Details on a study by Fleming Crim and his coworkers at the University of Wisconsin; Measurement of reactants; Functionality of molecular beam machines.

It is useful to describe the deformation characteristics of long biological macromolecules, such as deoxyribonucleic acid (DNA), by means of terms such as "bending", "stretching", or "twisting". These terms are borrowed from classical beam theory, a traditional and widely known subfield of continuum mechanics, whereas the standard numerical modeling procedure for macromolecules, which is molecular dynamics, does not allow for explicit introduction of the aforementioned deformation modes. This somehow puts some limit to the mechanical understanding of biological macromolecules. As a remedy, we here propose an upscaling (or homogenization) approach, spanning a new conceptual bridge from molecular dynamics to beam theory. Firstly, we apply the principle of virtual power (PVP) to classical continuum beams subjected to stretching and twisting, as well as to atomic compounds represented as discrete systems of mass points in the framework of molecular dynamics. Equating virtual power densities associated with continuum and discrete representations provides homogenization rules from the atomic compounds to the continuum beam line elements. Secondly, the forces acting on the aforementioned mass points are derived from energy potentials associated with bond stretching, valence and torsion angle variations, as well as electrostatic and van der Waals interactions. Application of this strategy to a specific DNA sequence consisting of 20 base pairs reveals deformation-dependent conformational changes, as well as paradox phenomena such as "stretching due to overwinding", in line with known experimental observations. [ABSTRACT FROM AUTHOR]

A bunching scheme for a long bunch with large energy spread is discussed. This neat bunching scheme is based on fast amplitude modulation by use of beating between frequencies. Tracking simulation results starting from a pion production target in a 16T magnetic field show the feasibility of a velocity compliant bunching scheme that uses time of flight information of the muons. Such a scheme can preserve the longitudinal emittance of the beam, and thus the energy spread can be kept small. [Copyright &y& Elsevier]

The performance in terms of sensitivity for measuring the continuous ( and δ) and discrete ( and ) oscillation parameters for the β-Beam and Super-Beam alone, and for their combination has been studied. A neutrino complex that includes a standard β-Beam and a Super-Beam facility is considered and the scenario where the neutrinos are sent toward a Megaton water Cerenkov detector located at the Fréjus laboratory (baseline 130 Km) is exploited. [Copyright &y& Elsevier]

The Beta Beam concept is a very promising technology to achieve high intensity and high purity neutrino beams. The main limitation of the Beta Beam in its baseline configuration (“low-γ option”) resides in the smallness of the parent ion energy. Here, the emerging electron neutrinos have an energy of a few hundreds MeV, i.e. a spectrum that significantly limits the physics reach of the facility. Moreover, in order to attain sensitivities comparable to a Phase II Superbeam, the construction of a Mton size detector is mandatory to overcome the smallness of the cross sections. In the following, we discuss a few recent proposals for an increase of the parent ion energy (“high-γ options”) with emphasis on physics performances and technological challenges. [Copyright &y& Elsevier]

The article reports on the use of molecular beam epitaxy to build materials atomic layer by atomic layer producing structures that do not and cannot exist in nature. Molecular beam epitaxy promises a generation of chips that will set new records for speed and performance. Molecular beam epitaxy is used in making gallium arsenide.

We present a theoretical study of the mixed-field-orientation of asymmetric-top molecules in tilted static electric field and nonresonant linearly polarized laser pulse by solving the time-dependent Schrödinger equation. Within this framework, we compute the mixed-field orientation of a state-selected molecular beam of benzonitrile (C7H5N) and compare with the experimental observations [J. L. Hansen et al., Phys. Rev. A 83, 023406 (2011)] and with our previous time-independent descriptions [J. J. Omiste et al., Phys. Chem. Chem. Phys. 13, 18815 (2011)]. For an excited rotational state, we investigate the field-dressed dynamics for several field configurations as those used in the mixed-field experiments. The nonadiabatic phenomena and their consequences on the rotational dynamics are analyzed in detail. [ABSTRACT FROM AUTHOR]

This article focuses on the use of a technique, known as the molecular beam epitaxy (MBE), developed by Jon Heffernan and his team, in building an indium-gallium-nitride blue-violet laser diode. The significance of that success was quick to register at the Sharp Corp., the Japanese consumer electronics and manufacturing company based in Osaka. Blue-violet-laser diodes are about to burst onto the consumer electronics market in a technology called Blu-ray, which exploits the short wavelength of blue light to record up to 27 gigabits or 13 hours of standard video on a single digital video disc. having a new way to build them could give the company access to a market that is expected to be worth five billion dollars within three years. MBE is a process in which gases are allowed to settle on a substrate kept in an ultrahigh vacuum.

Focuses on the development of blue-violet laser made by molecular beam epitaxy from Sharp Laboratories of Europe. Ky features; Device characteristics; Implications for laser production costs.