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A Penning-trap facility for high-precision mass spectrometry based on a novel detection method has been built. This method consists in measuring motional frequencies of singly-charged ions trapped in strong magnetic fields through the fluorescence photons from laser-cooled 40Ca+ ions, to overcome limitations faced in electronic single-ion detection techniques. The key element of this facility is an open-ring Penning trap coupled upstream to a preparation Penning trap similar to those used at Radioactive Ion Beam facilities. Here we present a full characterization of the trap and demonstrate motional frequency measurements of trapped ions stored by applying external radiofrequency fields in resonance with the ions' eigenmotions, in combination with time-of-flight identification. The infrastructure developed to observe the fluorescence photons from 40Ca+, comprising the 12 laser beams and the optical system to register the image in a high-sensitive CCD sensor, has been proved by taking images of the trapped and cooled 40Ca+ ions. This demonstrates the functionality of the proposed laser-based mass-spectrometry technique, providing a unique platform for precision experiments with implications in different fields of physics. [ABSTRACT FROM AUTHOR]

This study considers the position of clitics in verbal phrases with infinitives and gerunds, in which the speaker can choose to place the clitic in pre- or post-verbal position. The analysis is based on seventy-two one-hour tape-recorded conversations with speakers from Houston and the state of Michoacán, México. General results indicate a process of grammaticalization that appears as a strong tendency to place the clitic in front of the verbal phrase. A more in-depth analysis offers evidence that shows the role played by the contact situation with English; some characteristics of the verbal phrases studied seem to be sensitive to the contact situation. Reflexive verb constructions show a clear reduction of clitic climbing in groups of bilingual speakers. Although there is a strong tendency toward clitic climbing in most of the verbal phrases examined, some resistance, varying by generation, is observed with auxiliaries like empezar/comenzar con, saber, tratar de and venir a + infinitive. On the other hand, all bilingual speakers, regardless of generation, seem to follow the same general tendency of monolingual Spanish speakers to prefer clitic climbing in verbal phrases with gerunds, with incremental differences in verbal phrases like ir a, deber, querer, tener que, acabar de, and volver a + infinitive. [ABSTRACT FROM AUTHOR]

The radiation detection resonance ionization spectroscopy (RADRIS) technique enables laser spectroscopic investigations of the heaviest elements which are produced in atom-at-a-time quantities from fusion-evaporation reactions. To achieve a high efficiency, laser spectroscopy is performed in a buffer-gas environment used to thermalize and stop the high-energy evaporation residues behind the velocity filter SHIP. The required cyclic measurement procedure in combination with the applied filament collection for neutralization as well as confinement of the stopped ions and subsequent pulse-heat desorption constrains the applicability of the technique. Here, some of these limitations and also opportunities that arise from this unique measurement setup will be evaluated. [ABSTRACT FROM AUTHOR]

We report on the progress towards the implementation of a double trap system for the coupling of ion clouds stored in different traps through the charges they induce in a common electrode. The two traps have cylindrical symmetry and can be used either as Penning or Paul traps. The laser system for Doppler cooling of 40Ca+ clouds is described. The cooling can be performed differentially in the two traps, aiming at the study of the coupling between two clouds of ions at different temperatures. This setup is the starting point for the realization of energy transfer between two Doppler-cooled ions stored in different traps. We report on the status of the experiment and evaluate the performance required for an efficient coupling. [ABSTRACT FROM AUTHOR]