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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]