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A Be+ ion trap for H2+ spectroscopy / Un piège à ions Be+ pour la spectroscopie d'H2+Heinrich, Johannes 13 April 2018 (has links)
L'objectif du projet est la mesure du rapport de la masse de l'électron à celle du proton par spectroscopie vibrationnelle à deux photons sans effet Doppler de H2+. Le refroidissement des ions H2+ est nécessaire et ne peut être fait que par refroidissement sympathique par des ions Be+ refroidis par laser. La première partie présente la conception et la réalisation d'un piège linaire adapté au confinement des ions H2+ et Be+ et permettant les accès optiques nécessaires pour les lasers et l'imagerie. La seconde partie décrit les sources laser à 626 (à base de diodes laser ou de lasers à fibres) ainsi que la cavité de doublage de fréquence utilisés pour obtenir le faisceau à 313 nm pour refroidir les ions Be+. La dernière partie expose les premiers résultats obtenus qui montrent que le montage est opérationnel. Elle présente l'observation et la caractérisation de cristaux de Coulomb de Be+ ainsi que des cristaux de Coulomb mixtes Be+/H2+ où les ions H2+ sont créés par impact électronique à partir du gaz résiduel. Ces résultats montrent que le montage est prêt pour réaliser la spectroscopie de H2+. / The objective of the project is to perform high-resolution Doppler-free two-photon vibrational spectroscopy of the H2+ molecular ion for accurate electron to proton mass ratio determination. Trapping and laser-cooling of the H2+ ions is necessary. Since H2+ molecular ions cannot be directly laser cooled, a solution is the implementation of sympathetic cooling via a laser cooled Be+ ions. In the first part of this thesis the design and implementation of a linear Paul trap is presented. This trap is suitable to confine H2+ and Be+ ions while allowing good optical access for multiple laser sources and the imaging system. The second part describes a low power, diode based laser system to provide narrow linewidth 626nm light, and a high power, fiber laser based laser system. Subsequently, a bow-tie cavity is presented to frequency double the 626nm light to obtain 313nm light for Be+ Doppler-cooling. In the last part the operational readiness of the trap and the fiber laser based 313nm laser source is demonstrated by the observation of Be+ Coulomb crystals. Electron impact ionization of H2 present in the residual gas allows to observe sympathetic cooling and shows that the developed setup can provide the experimental conditions for precision spectroscopy of H2+.
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The Optical Spectroscopic And Photometric Observations Of The Optical Counterparts To The Be/x-ray Binary Systems: Gro J2058+42 And V0332+53Ozbey, Mehtap 01 August 2008 (has links) (PDF)
The spectroscopic and photometric observations of the optical
counterparts to the Be/X-ray binary systems GRO J2058+42 and V0332+53 (BQ Cam), taken with RTT150 (Russian-Turkish 1.5 meter Telescope), are presented in this study. The distance, color and the reddening estimates for both sources, obtained via photometric observations, are consistent with the previous results. The results of our spectroscopic observations performed between May 2006 and June 2008 for optical counterpart to GRO J2058+42 indicate that the double-peaked emission line profile turns into a single-peaked
emission after the last outburst of the system. Furthermore, the spectra of the source show clear evidence for the changes in the ratio of the double peaks of H alpha emission line indicative of the precession of the high-density regions confined in the disk. Unlike the spectra of counterpart to GRO J2058+42, the spectra of BQ Cam, taken between September 2006 and December 2007, exhibit single-peaked H alpha and HeI (Lambda 7065 Angstrom) emission lines. In addition, the equivalent width values of H alpha emission lines, shifts from the the laboratory wavelengths for H alpha and HeI emission lines and the variation in optical brightness of BQ Cam show a close correlation.
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Das "Verb" be in der englischen SatzstrukturBode, Stefanie, January 1900 (has links)
Thesis (doctoral)--Universität Göttingen, 2001. / Includes bibliographical references (p. 285-294).
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[en] REFLECTIONS ON THE (IN)CAPACITY TO BE ALONE / [pt] REFLEXÕES SOBRE A (IN)CAPACIDADE DE ESTAR SÓJOANA MARCOS CHISSINI 25 April 2022 (has links)
[pt] O presente trabalho tem como objetivo investigar as bases da capacidade de
um indivíduo estar só e apreender o que comprometeria a possibilidade de alguém
ser, existir e de se constituir em uma unidade, alcançando o crescimento emocional
e a autonomia. Para isso, foi desenvolvida uma pesquisa teórica a partir do método
conceitual analítico. A investigação foi fundamentada, principalmente, no
pensamento do psicanalista inglês Donald Winnicott. Em uma primeira parte,
investigou-se o aspecto positivo da solidão partindo da concepção winnicottiana do
estar só como uma capacidade. Na segunda parte, a capacidade de estar só foi
relacionada com o espaço potencial winnicottiano, partindo da releitura e da
compreensão de Thomas Ogden de que na capacidade de estar só a criança se torna
capaz de gerar um espaço continente no qual ela vive. Por fim, na terceira parte
desta pesquisa, refletiu-se sobre o aspecto desértico da solidão buscando apreender
possíveis dificuldades no desenvolvimento emocional primitivo que
inviabilizariam a vivência do estar só. Procurou-se compreender as ansiedades
primitivas e os processos defensivos envolvidos nos primórdios do
desenvolvimento, explorando a etiologia do falso self winnicottiano em
contraponto com o gesto espontâneo do bebê. / [en] The present work aims to investigate the basis of an individual s capacity to
be alone and to apprehend what would compromise the possibility of someone
being, existing and constituting a unit, achieving emotional growth and autonomy.
For this, a theoretical research was developed from the analytical conceptual
method. The investigation was based mainly on the theory of the English
psychoanalyst Donald Winnicott. In a first part, it was investigated the positive
aspect of aloneness based on the Winnicottian conception of being alone as a
capacity. In the second part, it was related the capacity to be alone with the
Winnicottian potential space, starting from the reinterpretation and understanding
of Thomas Ogden that in the capacity to be alone, the child becomes capable of
generating a continent space in which he lives. Finally, in the third part of this
research, it was contemplated the desert aspect of loneliness, seeking to understand
possible difficulties in primitive emotional development that would make the
experience of being alone unfeasible. It was investigated the primitive anxieties and
the defensive processes involved in the beginnings of development, exploring the
etiology of the Winnicottian false self in counterpoint to the baby s spontaneous
gesture.
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Skolval, likvärdighet och skolsegregation : En diskursanalytisk fallstudie av den svenska skolan enligt ’What’s the problem represented to be?’-metodenNilsson, Shanice January 2022 (has links)
This work is a discourse analysis on a case study of Swedish school politic. Whith Carol Bacchi’s ‘What’s the problem represented to be?’-method this thesis conducts an analysis of the two propositions ’Ett mer likvärdigt skolval’ and ’Ökad likvärdighet för skolhuvudmän’. The method’s strength is that it seeks what’s presupposed in policy and problematizes it. The research questions are from ‘What’s the problem represented to be?’ and are as follows: 1) What problem representations can be found in P58 and P161? Is anyone more prominent? 2) What presuppositions underpin this representation of the ‘problem’? 3) What’s left unproblematic? Can the ‘problem’ be thought about differently? The analysis showed that the problem is the high concentration of students with the same weak socioeconomic background at schools and school segregation which is contingent of the residential segregation. The presupposition to this problem representation is the idea of school as a democratic meeting point for students with different backgrounds. The school segregation causes the school to fail being a meeting point of that sort. The school choice enables school segregation and the so called ‘white flight’-phenomenon. The voluntary segregation was not accustomed for in the propositions but that provides ground for further research.
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[en] SER OR ESTAR: THAT S THE QUESTION!: A DESCRIPTIVE USAGE STUDY AIMING PORTUGUESE AS A SECOND LANGUAGE FOR FOREIGNERS / [pt] SER OU ESTAR: EIS A QUESTÃO!: UM ESTUDO DESCRITIVO DE USOS VOLTADO PARA O PORTUGUÊS COMO SEGUNDA LÍNGUA PARA ESTRANGEIROSBRUNO DE ANDRADE RODRIGUES 09 December 2016 (has links)
[pt] Este estudo, destinado ao ensino de Português como Segunda Língua para Estrangeiros (PL2E), visa à descrição e à sistematização dos usos dos verbos ser e estar articulados a sintagma nominal, sintagma adjetival e sintagma preposicional com base no corpus que compreende 7 episódios da primeira temporada do programa Os Normais, exibida pela Rede Globo de Televisão, no ano de 2001. A análise, orientada por pressupostos funcionalistas, procura evidenciar as condições semântico-sintáticas e sociocognitivas (contextuais) que determinam a seleção entre ser e estar, assumindo como pressuposto básico o caráter significativo e multifuncional dessas formas. Assim, mostramos que os referidos verbos tomam parte na construção do significado das orações em que figuram e que desempenham funções discursivas. Nossa análise permite-nos concluir que são três as ordens de fatores nas quais se baseia a seleção entre ser e estar: a estruturação semântico-sintática da oração; o conjunto de pressupostos que constituem os contextos socicognitivos dos interlocutores; e as funções discursivas a que servem esses verbos. / [en] This study, to be used in the teaching of Portuguese as a Second Language for Foreigners (PSLF), aims at the description and systematization of the uses of the verbs ser and estar connected to a nominal syntagm, to an adjectival syntagm and to a prepositional syntagm. The corpus include 7 episodes of the first season of the sitcom Os Normais, exhibited by the Rede Globo TV Network, in 2001. The analysis, carried out based on funcionalist principles, sought to show the semantic-syntatic and sociocognitive conditions (contextual) that determine the selection between ser and estar, adopting as assumption the meaningful and multifunctional nature from these forms. Therefore, we show that the above-mentioned verbs take part in the construction of the meaning of clauses wherein they occur and that they perform discourse functions. Our analysis enable us to conclude that there are three the types of factors in which the choise between ser and estar is based: the semantic-syntatic structure of the clause; the set of assumptions that constitute the sociocognitve contexts of the speakers; and the discursive functions that these verbs serve.
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Reasons to be DesiredGoldstein, Emily R 01 January 2015 (has links)
Through a comparison of Tennessee Williams’ Blanche in A Streetcar Named Desire and Neil LaBute’s Steph in reasons to be pretty, this thesis explores the ways in which the female position has both changed and remained relatively the same over the course of the last sixty years.
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Fruit and vegetable intake in relation to health-related and socio-economic characteristics among parents-to-be in Västerbotten, SwedenHendriks, Sophia, van Hooft, Jutta January 2012 (has links)
Background This study was part of the Salut programme with the goal to improve the health and well-being of the population of Västerbotten. The target group in this study were the parents-to-be. An adequate fruit and vegetable (FV) intake can contribute to a better health and can be influenced by several factors. This can be used to describe the characteristics for different groups.Aims The aim of this study was to describe the FV intake among parents-to-be in Västerbotten. A further aim was to examine what characterizes parents-to-be who eat different amounts of FV regarding to Body Mass Index (BMI), meal types, snack consumption, physical activity (PA), level of education, habits of life and satisfaction with economic situation.Method A cross-sectional study design was used. The data were collected by using health forms designed by Salut, which were distributed to the parents-to-be (nmothers=4352, nfathers/partners=3965) by midwives. Data was analyzed with SPSS. Chi2 test was used to analyse differences between those with a FV intake below or according the recommendation and Mann-Whitney U-Test was used to compare the mothers- with the fathers-to-be. The significance level was set to 0.05.Results Of the mothers- and fathers/partners-to-be respectively up to 23.5% and 6.9% met the FV recommendations. Based on the BMI, 25.9% of the mothers-to-be and 52.1% of the fathers/partners-to-be was overweight or obese. PA (p<0.001), habits of life (p<0.001) satisfaction with economic situation (pmothers=0.044, pfathers=0.005) and highest level of completed education (pmothers<0.001, pfathers=0.005) were positively associated with the FV intake.Conclusion The FV intake was associated with several characteristics and there were significant differences between the mothers- and fathers-to-be. This information can be used to design and implement an intervention to increase the FV intake to improve the health and well-being of the population of Västerbotten.
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Emission line stars in and beyond the Perseus ArmRaddi, Roberto January 2013 (has links)
I present low-resolution (Dl 6 A° ) follow-up spectroscopy of 370 Ha emitters (12 . r . 17) identified with IPHAS, in a 100 deg2 wide section of the Galactic plane that is located between ` = (120 ; 140 ) and b = ( 1 ; +4 ). Classical Be stars are found to be the most numerous group of the observed targets ( 60%). Sixty-eight classical Be stars have also been observed at higher spectral resolution (Dl 2 4 A° ) and S/N ratio, which allows spectral typing to an estimated precision of 1 sub-type. Colour excesses were measured via spectral energy distribution fitting of flux-calibrated data. I took care to remove the circumstellar contribution to the measured colour excess, using an established scaling to the Ha equivalent widths. In doing so, this method of correction was re-evaluated and modified to better suit the data at hand. Spectroscopic parallaxes were measured constraining the luminosity class via estimates of distances to main sequence A/F stars, which are found within a few arcminutes of each classical Be star on the sky. In order to probe the structure of the outer Galactic disc, I studied the spatial distribution of 63 out of 248 classical Be stars identified. Their cumulative distribution function with respect to the distance is statistically compatible both with a smooth exponential density profile and with a simple spiral arms representation. The distribution of reddenings of classical Be stars is compared with estimates of the total Galactic reddening along their sightlines. It is expected that the measured reddenings match the integrated Galactic values, for distant stars located outside the Galactic dust layer, or they are smaller than the asymptotic values if the stars are less distant. The outcome meets expectations, and lends support to the conclusion that the measured reddenings are determined to a precision of 10%. The sample of 248 objects doubles the number of known classical Be stars in this part of the Galactic plane. Unlike the pre-existing bright sample, the new objects are seen at large distances, between 2 – 8 kpc with typical E(B V) 0:9. Only four stars are members of known clusters. Ten classical Be stars are proposed to be well beyond the putative Outer Arm, at distances larger than 8 kpc. The large sample of stars, which has been identified here, is the result of a successful selection and analysis of classical Be stars that is offered for more exploitation in future. The proposition is that GAIA observations will use the present sample of classical Be stars as a new tracer of the Galactic disc.
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PHOTO-REVERBERATION MAPPING OF A PROTOPLANETARY ACCRETION DISK AROUND A T TAURI STARMeng, Huan Y. A., Plavchan, Peter, Rieke, George H., Cody, Ann Marie, Güth, Tina, Stauffer, John, Covey, Kevin, Carey, Sean, Ciardi, David, Duran-Rojas, Maria C., Gutermuth, Robert A., Morales-Calderón, María, Rebull, Luisa M., Watson, Alan M. 23 May 2016 (has links)
Theoretical models and spectroscopic observations of newborn stars suggest that protoplantary disks have an inner "wall" at a distance set by the disk interaction with the star. Around T Tauri stars, the size of this disk hole is expected to be on a 0.1 au scale that is unresolved by current adaptive optics imaging, though some model-dependent constraints have been obtained by near-infrared interferometry. Here we report the first measurement of the inner disk wall around a solar-mass young stellar object, YLW 16B in the rho Ophiuchi star-forming region, by detecting the light-travel time of the variable radiation from the stellar surface to the disk. Consistent time lags were detected on two nights, when the time series in H (1.6 mu m) and K (2.2 mu m) bands were synchronized while the 4.5 mu m emission lagged by 74.5 +/- 3.2 s. Considering the nearly edge-on geometry of the disk, the inner rim should be 0.084 au from the protostar on average, with an error of order 0.01 au. This size is likely larger than the range of magnetospheric truncations and consistent with an optically and geometrically thick disk front at the dust sublimation radius at similar to 1500 K. The widths of the cross-correlation functions between the data in different wavebands place possible new constraints on the geometry of the disk.
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