Programmable Trigger Logic Unit Based on FPGA Technology

A programmable trigger logic module (TRILOMO) was implemented successfully in an FPGA using their internal look-up tables to save Boolean functions. Up to 16 trigger input signals can be combined logically for a fast trigger decision. The new feature is that the trigger decision is VME register based. The changes are made without modifying the FPGA code. Additionally the module has an excellent signal delay adjustment.Comment: 4 pages, 4 figure

Differential Scattering Cross-Sections for the Different Product Vibrational States in the Ion-Molecule Reaction Ar+ + N2

The charge transfer reaction Ar+ + N2 --> Ar + N2+ has been investigated in a crossed beam experiment in combination with three-dimensional velocity map imaging. Angular differential state-to-state cross sections were determined as a function of the collision energy. We found that scattering into the first excited vibrational level dominates as expected, but only for scattering in the forward direction. Higher vibrational excitations up to v'=6 have been observed for larger scattering angles. For decreasing collision energy, scattering into higher scattering angles becomes increasingly important for all kinematically allowed quantum states. Our detailed measurements indicate that a quantitative agreement between experiment and theory for this basic ion-molecule reaction now comes within reach.Comment: accepted to Phys. Rev. Let

Strongly aligned and oriented molecular samples at a kHz repetition rate

We demonstrate strong adiabatic laser alignment and mixed-field orientation at kHz repetition rates. We observe degrees of alignment as large as cos\Theta=0.94 at 1 kHz operation for iodobenzene. The experimental setup consist of a kHz laser system simultaneously producing pulses of 30 fs (1.3 mJ) and 450 ps (9 mJ). A cold 1 K state-selected molecular beam is produced at the same rate by appropriate operation of an Even-Lavie valve. Quantum state selection has been obtained using an electrostatic deflector. A camera and data acquisition system records and analyzes the images on a single-shot basis. The system is capable of producing, controlling (translation and rotation) and analyzing cold molecular beams at kHz repetition rates and is, therefore, ideally suited for the recording of ultrafast dynamics in so-called "molecular movies".Comment: 6 pages, 4 figures, in press in Mol. Phys., accepted in February 2013, in final production (galley proofs done) since March 8, 2013, v3 only adds publication dat

Photodetachment of cold OH- in a multipole ion trap

The absolute photodetachment cross section of OH- anions at a rotational and translational temperature of 170K is determined by measuring the detachment-induced decay rate of the anions in a multipole radio-frequency ion trap. In comparison with previous results, the obtained cross section shows the importance of the initial rotational state distribution. Using a tomography scan of the photodetachment laser through the trapped ion cloud, the derived cross section is model-independent and thus features a small systematic uncertainty. The tomography also yields the column density of the OH- anions in the 22-pole ion trap in good agreement with the expected trapping potential of a large field free region bound by steep potential walls.Comment: Phys. Rev. Lett., in pres

Two-state wave packet for strong field-free molecular orientation

We demonstrate strong laser-field-free orientation of absolute-ground-state carbonyl sulfide molecules. The molecules are oriented by the combination of a 485-ps-long non-resonant laser pulse and a weak static electric field. The edges of the laser pulse create a coherent superposition of two rotational states resulting in revivals of strong transient molecular orientation after the laser pulse. The experimentally attained degree of orientation of 0.6 corresponds to the theoretical maximum for mixing of the two states. Switching off the dc field would provide the same orientation completely field-free

Strongly driven quantum pendulum of the OCS molecule

We demonstrate and analyze a strongly driven quantum pendulum in the angular motion of stateselected and laser aligned OCS molecules. Raman-couplings during the rising edge of a 50-picosecond laser pulse create a wave packet of pendular states, which propagates in the confining potential formed by the polarizability interaction between the molecule and the laser field. This wave-packet dynamics manifests itself as pronounced oscillations in the degree of alignment with a laser-intensity dependent period.Comment: 6 pages, 4 figure

Evaporation of buffer gas-thermalized anions out of a multipole rf ion trap

We identify plain evaporation of ions as the fundamental loss mechanism out of a multipole ion trap. Using thermalized negative Cl- ions we find that the evaporative loss rate is proportional to a Boltzmann factor. This thermodynamic description sheds new light on the dynamics of particles in time-varying confining potentials. It specifically allows us to extract the effective depth of the ion trap as the activation energy for evaporation. As a function of the rf amplitude we find two distinct regimes related to the stability of motion of the trapped ions. For low amplitudes the entire trap allows for stable motion and the trap depth increases with the rf field. For larger rf amplitudes, however, rapid energy transfer from the field to the ion motion can occur at large trap radii, which leads to a reduction of the effective trapping volume. In this regime the trap depth decreases again with increasing rf amplitude. We give an analytical parameterization of the trap depth for various multipole traps that allows predictions of the most favorable trapping conditions.Comment: Phys. Rev. Lett., in pres

Fundamentos del diseno e industrializacion de muebles de linea plana.

159 p.Las posibilidades de un país maderero, como lo es Chile, de incrementar sustancialmente sus exportaciones en el rubro muebles, están claramente demostradas en estudios comparativos realizados en otros países exportadores, por ejemplo, Taiwán, país importador de madera, exporta más de 2000 millones de dólares anuales. (INFOR, 2004) A nivel nacional, en los últimos años la industria manufacturera de muebles ha tenido un gran auge de exportaciones; este crecimiento ha generado necesidades inmediatas, entre las cuales se ha podido detectar: Falta de personal capacitado a nivel de trabajadores y profesionales, falta de diseños propios, problemas de calidad, tecnologías atrasadas, etc. (INFOR, 2004) La demanda por muebles continuará aumentando: El país sólo podrá hacer frente a esta demanda en la medida que tenga personal capacitado, una red de productores; pequeños, medianos y grandes, pueda ofrecer diseños, que siendo propios tengan acogida en el mercado internacional, además de un sistema de Calidad para la fabricación de muebles, donde se realicen cabalmente las uniones y se escoja apropiadamente los herrajes de acuerdo al diseño de éstos. La memoria desarrollada pretende en lo fundamental capacitar, transfiriendo al sector productivo, información sobre diseños, sistemas constructivos adecuados para el mercado interno y de exportación y el uso de maquinarias. De acuerdo a lo anterior esta memoria está destinada a la descripción de los principales aspectos del funcionamiento y el uso de maquinaria, sistemas de herrajes y diseño de muebles de línea plana; esto se consiguió adaptando experiencias extranjeras en general, a la realidad nacional, mediante bibliografía obtenida a través de medios digitales, como también por revisiones bibliográficas

How can a 22-pole ion trap exhibit 10 local minima in the effective potential?

The column density distribution of trapped OH$^-$ ions in a 22-pole ion trap is measured for different trap parameters. The density is obtained from position-dependent photodetachment rate measurements. Overall, agreement is found with the effective potential of an ideal 22-pole. However, in addition we observe 10 distinct minima in the trapping potential, which indicate a breaking of the 22-fold symmetry. Numerical simulations show that a displacement of a subset of the radiofrequency electrodes can serve as an explanation for this symmetry breaking

Improved spatial separation of neutral molecules

We have developed and experimentally demonstrated an improved electrostatic deflector for the spatial separation of molecules according to their dipole-moment-to-mass ratio. The device features a very open structure that allows for significantly stronger electric fields as well as for stronger deflection without molecules crashing into the device itself. We have demonstrated its performance using the prototypical OCS molecule and we discuss opportunities regarding improved quantum-state-selectivity for complex molecules and the deflection of unpolar molecules.Comment: 6 figure