En esta tesis se presenta la primera observación en rayos X con Chandra del sistema binario de alta masa 4u1700-37 durante una fase de eclipse del objeto compacto. El principal objetivo es estudiar la estructura/física de las inhomogeneidades del viento estelar a través de la espectroscopía de alta resolución. Se encuentra que: a) el brillo de las líneas de emisión de las trasiciones de la capa K, correspondientes a especies neutras, están directamente correlacionadas con la iluminación del continuo. Estas líneas no disminuyen significativamente durante el eclipse. Una posible explicación sería que estas líneas provinieran principalmente del viento estelar. b) Las líneas altamente ionizadas Fe xxv y Fe xxvi Ly alpha, disminuyen durante el eclipse, por lo que deberían producirse cerca del objeto compacto donde el parámetro de ionización es mayor que 3. c) Para describir las líneas de emisión del continuo, se requiere utilizar la suma de dos modelos de plasma fotoionizado, uno con baja ionización ( parámetro de ionización = -1), y otro con alta (parámetro de ionización = 2.4). De las medidas obtenidas para las líneas, podemos estimar un cociente de densidades alrededor de 300 entre las zonas de mayor y menor densidad del viento. Para ajustar el complejo de He-like Si xiii, el plasma requiere un ensanchamiento de las líneas. Para reproducir el flujo observado de las líneas r y f, es necesario añadir una tercera componente de origen colisional, plasma ionizado colisionalmente. d) El ancho de las líneas no está resuelto, a excepción del Silicio. No hay una clara distinción o separación radial entre las especies quasi-neutras e inonizadas, lo que es consistente con las inhomogeneidades frías embebidas en el medio caliente y enrarecido que podrían estar constituyendo el viento. Se estudia también la naturaleza del objeto compacto mediante evidencias de enfriamiento Compton durante un estallido de rayos X.

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The high mass X-ray binary 4U 2206+54 has been a very controversial system due to variability in spectral data as well as photometric data. We, at Brigham Young University, have been observing this system in multiple filters with several telescopes. This thesis presents our methods of observations, reductions, and results. It also compares what we have been detecting to other groups looking at the same target in different wavelengths. Furthermore, this thesis discusses some of the peculiarities of 4U 2206+54 and possible theories to explain these phenomena. Based on our photometric observations for the past three years, we believe the period of 4U 2206+54 is 25.1 days. Furthermore, spectral data show an unusual double-peaked Hα feature. We believe the primary star BD +53°2790 is a single star, and that the system is surrounded by a gas and dust shell.

In this thesis, X-ray spectral and pulse timing analysis of the high mass X-ray binary pulsar 4U 1907+09, based on the observations with Rossi X-ray Timing Explorer (RXTE) and International Gamma-Ray Astrophysics Laboratory (INTEGRAL), are presented. INTEGRAL (October 2005 - November 2007) and RXTE (June 2007 - December 2008) observations confirm that the luminosity of the source is highly variable such that, flaring and dipping activities are observed. The results of time-averaged energy spectra of RXTE and INTEGRAL observations are consistent with the previous studies. Orbital phase resolved spectroscopy with RXTE data, reveals that the Hydrogen column density varies through the orbit reaching to its maximum value just after periastron. This variation approves that the location of the absorbing material is the accretion flow. A slight spectral softening with increasing luminosity is aslo observed. 4U 1907+09 had been steadily spinning down for more than ~15 years with a rate of -3.54x10-14 Hz s-1. RXTE observations of the source in 2001 showed a ~60% decrease in the spin-down rate and INTEGRAL observations in 2003 showed a reversal to spin-up. The timing analysis presented in this thesis reveals a new spin-down episode with a rate of -3.59x10-14 Hz s-1, which is close to the previous steady spin-down rate. This result implies that a recent torque reversal before June 2007 has taken place. The reversal is a rare event for 4U 1907+09 and it indicates the variations in the mass accretion rate and/or geometry. Using RXTE observations, 24 new pulse periods are measured to demonstrate the period evolution. Energy resolved pulse profiles confirm that the profile has a double peak sinusoidal shape at energies below 20 keV, whereas the leading peak significantly loses its intensity above 20 keV. This energy dependence indicates that the physical circumstances of the two polar caps are different.

The risk for an adolescent to develop risk behaviors decrease when he/she feels to be included in and to have an influence on the society. Previous research shows that opportunities for young people to feel involved in the society are limited. Every year, here 4U offers a tolerance-education to young people. This study aims to investigate whether the tolerance-education has met its objectives. The aim of the study is to investigate whether and how here 4U:s tolerance-education affected young people´s sense of participation in the society and civic-engagement and whether it led to personal development. The study applies a qualitative method, with semi-structured interviews and applies a target selection of andolescents based on criterias that enable for the studys aim to be answered. The informants are six young people aged 16–22. A manifest content analysis has been applied to analyze the collected material. The results of the study show that young people feels that they have more opportunities and will to engage in society after the tolerance-education. It also demonstrates that the tolerance-education has contributed to young people´s opportunities for participation in the society. Furthermore, the results shows that the tolerance-education has contributed to the personal development of young people by giving them a chance to build confidence and self-esteem. / Genom att inkludera ungdomar i samhället minskar risken att de utvecklar ett risktagande beteende. Tidigare forskning påvisar att möjligheterna för ungdomar att känna sig delaktiga i samhället är begränsade. Varje år erbjuder here 4U en toleransutbildning till ungdomar. Den här studien syftar till att undersöka om toleransutbildningen uppfyllt dess mål. Utefter bakgrunden är studiens syfte att undersöka om och i så fall hur here 4U:s toleransutbildning påverkat ungdomars känsla av delaktighet i samhället, samhällsengagemang samt om den lett till personlig utveckling. Studien tillämpar en kvalitativ metod, har semistrukturerade intervjuer och tillämpar ett målstyrt urval. Informanterna är sex ungdomar i åldern 16–22. En kvalitativ analysprocess i form av en manifest innehållsanalys har tillämpats för att analysera det insamlade materialet. Studiens resultat visar att ungdomarna upplever sig ha bättre förutsättningar och vilja att engagera sig i samhället efter toleransutbildningen. Det påvisar även att toleransutbildningen bidragit till att ungdomarna fått möjligheter till delaktighet. Vidare visar det framtagna resultatet att toleransutbildningen bidragit till ungdomarnas personliga utveckling genom att de fått chans att bygga upp en självsäkerhet och en självkänsla.