1,268 research outputs found

    Exoplanets in Open Clusters and Binaries: New Constraints on Planetary Migration

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    In this dissertation, we present three complementary studies of the processes that drive planetary migration. The first is a radial-velocity survey in search of giant planets in adolescent (\u3c1 \u3eGyr) open clusters. While several different mechanisms may act to drive giant planets inward, only some mechanisms will excite high eccentricities while doing so. Measuring the eccentricities of young hot Jupiters in these clusters (at a time before the orbits have had a chance to circularize due to tidal friction with their host stars) will allow us to identify which mechanisms are most important. Through this survey, we detect the first 3 hot Jupiters in open clusters (and at least 4 long-period planets), and we measure the occurrence rate of hot Jupiters in clusters to be similar to that of the field (~1%). We determine via analyses of hot Jupiter eccentricities and outer companions in these systems that high eccentricity migration mechanisms (those requiring the presence of a third body) are important for migration. The second project, an adaptive optics imaging survey for stellar companions to known hot Jupiter hosts, aims to determine the role that stellar companions in particular play in giant planet migration. Through a preliminary analysis, we derive a lower limit on the binary frequency of 45% (greater than that of the typical field star), and we find that the presence of a companion is correlated with misalignment of the spin-orbit angle of the planetary system, as would be expected for stellar Kozai-Lidov migration: at least 74% of misaligned systems reside in binaries. We thus conclude that among high eccentricity migration mechanisms, those requiring a stellar companion play a significant role. Finally, we describe simulations of measurements of the planet population expected to be discovered by TESS, and use these to demonstrate that a strong constraint on the obliquity distribution of small planets can be derived using only TESS photometry, Gaia astrometry, and vsin(i) measurements of the host stars. This obliquity distribution will be a key piece of evidence to help detemine the likely formation and migration histories of small planets, and can contribute to the assessment of the potential for Earth-like planets to harbor life

    From Parlor to Forest Temple: An Historical Anthropology of the Early Landscapes of the National Camp-Meeting Association for the Promotion of Holiness, 1867-1871.

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    This dissertation is an historical anthropology investigating the late 19th century liturgical landscapes of the National Camp‐Meeting Association for the Promotion of Holiness, an organization of Methodist clergy who sought ecclesiastical and social reform primarily through camp‐meeting revivals promoting the experience of entire sanctification. National camp meetings drew from the liturgical and architectural traditions of early 19th century frontier revivalism, yet, as this dissertation argues, these meetings were not simply an appropriation of the structure of Second Great Awakening revivals for the purpose of promoting holiness theology in decidedly more urban areas of the Northeast and Mid‐Atlantic. Rather, these meetings were a (re)imagining of the cultural practice of the camp‐meeting through a Victorian system of symbolic meanings, a middle‐class, (ex)urban geographic context, and a distinctive set of liturgical performances, social interactions, and cognitive‐environmental and architectural cues designed to elicit a changed subjectivity among attendees. Each of these transformations shaped the social space, architectural configuration, and site selection of the liturgical landscapes of the National Camp‐Meeting Association, and it is these spatial and material traces that offer a substantial body of data for the interpretation of past religious and ritual landscapes in North America. Such interpretation of revival landscapes is possible through a process of cross‐mending archival sources (diaries, autobiographies, biographies, historic correspondence, newspaper reports, sermon texts, organizational documents, maps, photographs), material culture, archaeological reports, geo‐spatial and environmental data to reconstruct and thickly interpret the ritual landscapes of three early meetings of the National Camp‐Meeting Association for the Promotion of Holiness – Vineland, New Jersey, Manheim, Pennsylvania, and Round Lake, New York. In its results, this dissertation argues for a significant connection between Methodism, geographic regions, and 19th century holiness practices, and an interpretation of holiness revivalism as a means of renegotiating moral orders amidst industrialization, urbanization, vacationing, and changing social fault lines in the church including race and gender

    Kepler-432: A Red Giant Interacting with One of its Two Long-period Giant Planets

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    We report the discovery of Kepler-432b, a giant planet (M_b = 5.41^(+0.32)_(-0.18)M_Jup, R_b = 1.145^(+0.036)_(-0.039)R_Jup) transiting an evolved star (M_* = 1.32^(+0.10)_(-0.07)M_⊙, R_* = 4.06^(+0.12)_(-0.08)R_⊙) with an orbital period of P_b = 52.501129^(+0.000067)_(-0.000053) days. Radial velocities (RVs) reveal that Kepler-432b orbits its parent star with an eccentricity of e=0.5134^(+0.0098)_(-0.0089), which we also measure independently with asterodensity profiling (AP; e=0.507^(+0.039)_(-0.114)), thereby confirming the validity of AP on this particular evolved star. The well-determined planetary properties and unusually large mass also make this planet an important benchmark for theoretical models of super-Jupiter formation. Long-term RV monitoring detected the presence of a non-transiting outer planet (Kepler-432c; M_c sin i_c = 2.43^(+0.22)_(-0.24) M_Jup, P_c = 406.2^(+3.9)_(-2.5) days), and adaptive optics imaging revealed a nearby (0".87), faint companion (Kepler-432B) that is a physically bound M dwarf. The host star exhibits high signal-to-noise ratio asteroseismic oscillations, which enable precise measurements of the stellar mass, radius, and age. Analysis of the rotational splitting of the oscillation modes additionally reveals the stellar spin axis to be nearly edge-on, which suggests that the stellar spin is likely well aligned with the orbit of the transiting planet. Despite its long period, the obliquity of the 52.5 day orbit may have been shaped by star–planet interaction in a manner similar to hot Jupiter systems, and we present observational and theoretical evidence to support this scenario. Finally, as a short-period outlier among giant planets orbiting giant stars, study of Kepler-432b may help explain the distribution of massive planets orbiting giant stars interior to 1 AU

    A Family Health Impact Analysis of Current United States Gun Policy

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    Gun violence in the United States is an epidemic that threatens the health and safety of individuals and families. It also has a particularly disproportionate impact on Black and Brown communities, women, sexual and gender minorities, and those living in poverty. However, despite increased recognition of the pervasive, pernicious, and inequitable impacts of gun violence, federal policy to curb them remains relatively stagnant. A family health impact analysis suggests that public policy efforts can best support family well-being through laws that restrict gun ownership for those who have identifiable risk factors for violence; through expanded  implementation of gun violence restraining orders; through requirements for both universal background checks at the federal level and national and community-specific gun violence awareness campaigns; and through incorporation of the expertise of family professionals

    Colouring naphthalene diimides

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    Naphthalene diimides have been explored in a wide variety of ways; They are a promising candidate for organic electronics, boasting the ability to form n-type semiconductor materials, the stability of their anions further aiding in this regard. Their electron poor aromatic core can be used in host guest chemistry to generate interlocked species. The ability to tune their electronic properties and how this could be manipulated to create photovoltaic devices is primarily focus of this thesis. A series of naphthalene diimides substituted at the core with morpholine moieties have been synthesized and their optical and electronic properties have been probed. Interestingly these species were found to not follow the typical trends for core substituted naphthalene diimides. Through further investigation it was revealed that this unexpected behavior was due to the conformation of core substituents, typically considered unimpactful. In addition to these species, more complex naphthalene diimide systems, core substituted with phenothiazine and phenoxazine, have been synthesized. By combination of the electron deficient naphthalene diimide with the electron rich phenothiazine and phenoxazine electron donor-acceptor species have been created. These species can be excited by visible light and upon excitation have the potential to generate a charge separated state, which could be used to generate current in a photovoltaic device. Finally a naphthalene diimide furnished with two BODIPY units was synthesized in an attempt to utilize it as the central rod of a rotaxane. The electronic properties of this rod species were also attempted to be modulated via thionation of the naphthalene diimide core. These species would be used to assess the viability of utilizing BODIPY as a light harvesting antenna for naphthalene diimide systems

    A review of the safety climate literature as it relates to naval aviation.

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    The purpose of this literature review is to provide the background to an evaluation of the utility of the Command Safety Assessment Survey (CSAS) as a valid predictor of future mishaps. The end goal is to be able to use the survey to identify at risk U.S. Naval squadrons prior to the occurrence of mishaps. Safety climate describes employees' perceptions, attitudes, and beliefs about risk and safety (Mearns & Flin, 1999). Safety climate is most commonly evaluated using questionnaires. Although assessments of safety climate are not widespread in civil aviation, the United States Navy has been using the CSAS since 2000 to measure the safety climate of aviation squadrons. This review argues that a comprehensive assessment of the construct (the extent to which the questionnaire measures what it is intended to measure) and discriminate validity (correlate the data from the questionnaire with a criterion variable, such as accidents) of the CSAS should be carried out. This assessment is necessary to ensure that squadron Commanding Officers, and senior leadership, are being provided with valid and reliable information on squadron safety climate.Approved for public release; distribution is unlimited

    Colouring naphthalene diimides

    Get PDF
    Naphthalene diimides have been explored in a wide variety of ways; They are a promising candidate for organic electronics, boasting the ability to form n-type semiconductor materials, the stability of their anions further aiding in this regard. Their electron poor aromatic core can be used in host guest chemistry to generate interlocked species. The ability to tune their electronic properties and how this could be manipulated to create photovoltaic devices is primarily focus of this thesis. A series of naphthalene diimides substituted at the core with morpholine moieties have been synthesized and their optical and electronic properties have been probed. Interestingly these species were found to not follow the typical trends for core substituted naphthalene diimides. Through further investigation it was revealed that this unexpected behavior was due to the conformation of core substituents, typically considered unimpactful. In addition to these species, more complex naphthalene diimide systems, core substituted with phenothiazine and phenoxazine, have been synthesized. By combination of the electron deficient naphthalene diimide with the electron rich phenothiazine and phenoxazine electron donor-acceptor species have been created. These species can be excited by visible light and upon excitation have the potential to generate a charge separated state, which could be used to generate current in a photovoltaic device. Finally a naphthalene diimide furnished with two BODIPY units was synthesized in an attempt to utilize it as the central rod of a rotaxane. The electronic properties of this rod species were also attempted to be modulated via thionation of the naphthalene diimide core. These species would be used to assess the viability of utilizing BODIPY as a light harvesting antenna for naphthalene diimide systems
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