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Showing 1 to 16 of 16 for “"protoplanetary disk"”.
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Planetesimal and Protoplanet Dynamics in a Turbulent Protoplanetary Disk
In a young protoplanetary disk, planetary objects undergo orbital migration due to the gravitational torques exerted by their surrounding gas. It has been an outstanding issue that an earth-sized planet embedded in a gas-rich environment may rapidly migrate into its host star. In this dissertation, …
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Analysis of Molecular Variability Due to Accretion Bursts in the Protoplanetary Disk of Ex Lup as Observed with the James Webb Space Telescope
Protoplanetary disks are structures that form around a pre-main sequence star as a result of conservation of angular momentum during collapse of dense cores in star-forming regions. They accrete gas onto the central proto-star, and are the sites of planet formation. Early in their lifetime, disk …
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Magnetic fields in the early solar system
… system were embedded in the ionized gas of the protoplanetary disk itself. Soon after, newly formed protoplanets may have harbored magnetic core dynamos. Paleomagnetic analysis of ancient samples permits direct constraints on these early solar system magnetic fields. Here I present paleomagnetic …
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Physical and Chemical Properties of Matrix in Primitive Chondrites
… to be the remnants of the dust and gas of the protoplanetary disk that allows us to better understand chemical and physical properties of this precursor material. Four pristine primitive meteorites were selected: Acfer 094 (C2-ung.), ALHA77307 (CO3), MIL 07687 (C3-ung.) and QUE 99177 (CR2). The …
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Characterizing sub-mm observations of protoplanetary disks at super-resolution scales
… span Gyr of evolution, from their formation in protoplanetary disks and continued growth in debris disks to their dynamical evolution in exoplanetary systems and ultimate accretion onto white dwarfs. Measurements in each of these eras can be used to inform study in the others. Interferometry …
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Paleomagnetic Investigation of Enstatite Chondrite Chondrules: Implications for the Solar Nebula
… were characterized by the rapid evolution of the protoplanetary disk. A magnetic field governed the highly efficient mass and angular momentum transport systems. Paleomagnetic measurements of chondrites have constrained the intensity of the nebular field between ∼3-7 AU. Previous work on two dusty …
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Remanent magnetization in angrite NWA 4931
… and may record planetesimal dynamo activity and protoplanetary disk fields in the early solar system. Towards this goal, the natural remanent magnetism and its origin were examined in newly discovered angrite NWA 4931. Measurements were conducted on subsamples cut from various distances along a …
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Spectroscopic and spectro-astrometric analysis of T Tauri Stars
… we must investigate the composition of the protoplanetary disk from which the solar system formed. To infer this, we study analogs to the early solar system called T Tauri stars. These objects are low-mass, pre-main sequence stars surrounded by circumstellar disks of material from which …
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Employing Magnetic Field Records at Key Moments in Planetary Evolution
… solar system and planetary evolution: I) The protoplanetary disk; II) The initial melting on the first planetary bodies; and III) The early interior evolution of modern planets. I address Stage I through a paleomagnetic analysis of returned samples from asteroid Ryugu to determine the role of …
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Probing planetary system histories via observations, experiments, and modelling of circumstellar gas and dust
Circumstellar disks of gas and dust are integral parts of planetary systems from formation to maturation. Protoplanetary disks, the name for circumstellar material at the earliest stages of a stellar lifetime, provide key information about the formation processes of planets, and therefore of the …
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OBSERVATIONAL CONSTRAINTS OF THE INTERACTION BETWEEN PLANETS AND PROTOPLANETARY DISKS
… process, emerging from the material within the protoplanetary disk surrounding the young protostar. Interactions between these newly formed planets and the disk create observable effects on the disk itself, which can be detected in the sub-millimeter to centimeter wavelength range through …
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Isotopes as a Tool for Exploring Exoplanet Atmospheres
… location and heating processes within the protoplanetary disk. Through simulations, I assessed the detectability of isotopologues in the atmospheres of exoplanets with JWST and determined the best dozen targets to measure atmospheric carbon isotope ratios using transmission spectroscopy. …
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Investigations of close-in exoplanets : starspot transits, and ultra-short period planets
… a rotating envelope of gas collapses into a disk-shaped protoplanetary disk from which the planets form. But this is not the case for all exoplanets. Close-in gas giants are frequently found in orbits that are tilted respect to the spin axis, a sign that some process is altering the orbits of …
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SHEDDING NEW LIGHT ON OLD DATA: FINDING NEW RESULTS FOR EXOPLANET SCIENCE IN ARCHIVAL DATA
… attributed to material at the inner edge of the protoplanetary disk. This behaviour is often variable and aperiodic, suggesting that the occulting material is changing in morphology on the time scale of a single orbit. Using python’s scikit-learn I have developed a code that utilises a Random …
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Development of a Self-Consistent Gas Accretion Model for Simulating Gas Giant Formation in Protoplanetary Disks
The number of extrasolar planet discoveries has increased dramatically over the last 15 years. Nearly 700 exoplanets have currently been observed through a variety of observation techniques. Most of the currently documented exoplanets differ greatly from the planets in our own Solar System, with …
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NATURAL ANALOGUES OF PLANET MERCURY’S SURFACE: MINERALOGICAL AND SPECTROSCOPIC ASPECTS
… that Mercury formed in the inner part of the protoplanetary disk from highly reduced precursor materials. However, the interpretation of Mercury’s spectral properties remains complex due to the effects of space weathering (SpWe) and extreme temperature variations affecting the surface. Since …