Дисертації з теми "Transiti planetari"
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Giacobbe, Paolo. "Photometric transit search for planets around cool stars from the Western Italian Alps: the APACHE survey." Doctoral thesis, Università degli studi di Trieste, 2014. http://hdl.handle.net/10077/9965.
Повний текст джерелаSmall-size ground-based telescopes can effectively be used to look for transiting rocky planets around nearby low-mass M stars using the photometric transit method. Since 2008, a consortium of the Astrophysical Observatory of Torino (OATo-INAF) and the Astronomical Observatory of the Autonomous Region of Aosta Valley (OAVdA) have been preparing for the long-term photometric survey APACHE (A PAthway toward the Characterization of Habitable Earths), aimed at finding transiting small-size planets around thousands of nearby early and mid-M dwarfs. APACHE uses an array of five dedicated and identical 40-cm Ritchey-Chretien telescopes and its routine science operations started at the beginning of summer 2012. Here I present the results of the `pilot study', a year-long photometric monitoring campaign of a sample of 23 nearby dM stars, and of the APACHE survey first year data. In these studies, I set out to (i) demonstrate the sensitivity to > 2 Rearth transiting planets with periods of up to a few days around our programme stars, through a two-fold approach that combines a characterization of the statistical noise properties of our photometry with the determination of transit detection probabilities via simulations; and (ii), where possible, improves our knowledge of some astrophysical properties (e.g. activity, rotation) of our targets by combining our differential photometric measurements with spectroscopic information from the long-term programme GAPS with the HARPS-N spectrograph on the Telescopio Nazionale Galileo. Furthermore, cool M dwarfs within a few tens of parsecs from the Sun are becoming the focus of dedicated observational programs in the realm of exoplanet astrophysics that will make use of astrometric measurements. I present numerical simulations to gauge the Gaia potential for precision astrometry of exoplanets orbiting a sample of known dM stars within ~ 30 pc from the Sun. I then investigate some aspects of the synergy between the astrometric data expected from the Gaia mission on nearby M dwarfs and the APACHE program.
XXV Ciclo
1985
Aigrain, Suzanne. "Planetary transits and stellar variability." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614684.
Повний текст джерелаMcQuillan, Amy. "Stellar variability and rotation in Kepler planetary transit search data." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:802a873d-650f-4f0b-b814-f8397b2798e2.
Повний текст джерелаDe, Marchi Fabrizio. "Variable stars and planetary transit search in super metal-rich open clusters." Doctoral thesis, Università degli studi di Padova, 2008. http://hdl.handle.net/11577/3427100.
Повний текст джерелаStreet, Rachel. "A search for extra-solar planetary transits in the field of open cluster NGC 6819." Thesis, University of St Andrews, 2002. http://hdl.handle.net/10023/12939.
Повний текст джерелаBallerini, Paola. "Effects of starspots activity on optical and near infrared observations of planetary transits." Doctoral thesis, Università di Catania, 2013. http://hdl.handle.net/10761/1377.
Повний текст джерелаNisley, Ishara. "Transit timing variations of the exoplanet K2-25b." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/117447.
Повний текст джерелаCataloged from PDF version of thesis. "May 16, 2017." "This thesis was submitted to the Institute Archives without all the required signatures"--Disclaimer Notice page.
Includes bibliographical references (page 53).
Transit light curves of the exoplanet K2-25b were studied to examine the possibility of transit timing variations (TTVs) in the system, which could imply the presence of a perturbing planet. Observations of K2-25b transits were taken using 14-inch and 24-inch telescopes at Wallace Astrophysical Observatory. Two transit light curves were fit using an MCMC implementation to find the orbital period, planetary radius, and semi-major axis. A new period calculation yielded an orbital period of 3.48457 +/-0.00004, consistent with the period of 3.484552 +0.000044/-0.000036 from Mann et al. 2016. No significant variations were found in the midtimes of the new transit observations when comparing them to the midtime originally published in Mann et al. 2016. Future observations will require smaller uncertainties to meaningfully constrain the mass and period of potential perturbing planets. Signal-to-noise ratio calculations showed that telescopes over approximately 2.2 meters in diameter have better potential to detect small TTVs.
by Ishara Nisley.
S.B.
Adams, Elisabeth Rose. "Transit timing with fast cameras on large telescopes." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59737.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 171-178).
Timing and system parameters were measured for seven transiting exoplanets: OGLETR- 56b (11 transits), OGLE-TR-132b (7), OGLE-TR-111b (6), OGLE-TR-113b (6), CoRoT-2b (3), OGLE-TR-10b (3), and XO-2b (2). Ground-based observations of 38 transits were made using three new frame-transfer instruments: POETS and MagICe2v on the 6.5m Magellan telescopes, and MORIS on the 3m IRTF. For each planet, all transit light curves including available literature data were jointly fit using a Monte Carlo Markov Chain method, providing accurate new values for the planetary radius and other parameters. Transit ephemerides have been updated and transit midtimes have been investigated for potential transit timing variations (TTVs) caused by other planets or moons. Our transit midtime analysis contradicts a claimed TTV for OGLE-TR-111b (Diaz et al., 2008), finding no evidence in data from 2005-2009. The radius, 1.019 + 0.026 Rj, is intermediate to previous values (Winn et al., 2007; Diaz et al., 2008). We confirm the radius of OGLE-TR-56b, which previously had only one light curve (Pont et al., 2007), as 1.332 ± 0.063 Rj, but find a longer duration by 15 minutes, while the orbital period, 1.2119094 ± 0.0000024, is unchanged. Times for OGLE-TR-10b are consistent with the ephemeris of Holman et al. (2007), though two literature transits show large deviations (586 ± 86 s; Pont et al., 2007) and (-612 ± 26 s; Bentley et al., 2009). Times for four planets (OGLE-TR-113b, OGLE-TR-132b, CoRoT-2b, and XO-2b), with midtime errors as small as 9 s, agree with published ephemerides and show no signs of TTVs. The orbital period of OGLE-TR-113b derived from new data from 2007-2009, however, is shorter by 0.24 ± 0.12 s compared to the period calculated for literature data from 2002 and 2005. If confirmed, this would be the first detection of a change in the orbital period of an exoplanet, which could be caused by orbital decay as the planet falls onto its star.
by Elisabeth Rose Adams.
Ph.D.
Morley, Caroline V. "Measuring transit timing variations of exoplanets using small telescopes." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/114139.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (pages 57-58).
Transits of exoplanets were observed from June 2009 through January 2010. Six transit light curves are presented in this paper for three planets: WASP-10b, WASP- 11/HAT-P-10b, and TrES-3. Measurements of the planetary radii, semi-major axis, transit duration, and period confirmed literature values to within two sigma. Transit timing variations were not observed in these systems, but calculations show that it would be possible to measure transit timing variations induced by large exomoons (greater than about 6 Earth masses) in the WASP-11/HAT-P-10b system. Challenges of exoplanet observation from small telescopes are discussed. It was determined that overall, transit measurements of many exoplanets using small telescopes can be successful and scientifically useful.
by Caroline V. Morley.
S.B.
DeCroix, David Scot. "Large-eddy Simulations of the Convective and Evening Transition Planetary Boundary Layers." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20010319-182404.
Повний текст джерелаLarge-eddy simulation (LES) is a very useful tool in computationalfluid dynamics. The LES model allows one to solve a filtered set of theNavier-Stokes equations, thereby explicitly resolving scales of motionlarger than the discretization or grid size. Those motions smaller thanthe grid size are parameterized using a so-called subgrid scale model.
In this series of papers, we will use the TASS LES model, originallya cloud model, which has been modified to simulate planetary boundarylayer turbulence. We will first introduce the LES model and a newgrid-nesting method for the LES. Then we will present simulations ofthe convective planetary boundary layer, and then use the LES to studythe decay of convective planetary boundary layer turbulence to a stablystratified state.
The LES model has been modified to include a grid nesting capability.Grid meshes of higher resolution may be embedded within the LES enablingone to resolve smaller scales of motion (turbulence) than would bepossible by using a single grid mesh. The grid nesting methodology isdescribed in detail in Chapter 2.
In Chapter 3, the nested-grid LES will be applied to thesimulation of the convective planetary boundary layer. We will usea total of three grid meshes to increase the resolution in the surfacelayer, allowing a detailed analysis of the turbulence near the surface ofthe earth.
In Chapter 4, we will focus on applying Rayleigh Benardconvection criteria, using a linearized perturbation method,to the surface layer of a CBL produced by large-eddy simulation.Similarities and differences will be discussed between the LESproduced surface layer and classical Rayleigh-Benard convection theory.
In Chapter 5, using a large-eddy simulation model, we willexamine in detail the turbulent kinetic energy (TKE) budget during theevening transition. The simulation will be performed in order to compareto observations gathered at the Dallas-Fort Worth International Airport,Fort-Worth, TX. during September and October 1997.
In Chapter 6 the decay of planetary boundary layerturbulence during the evening transition will be studied. In previousstudies of the decay of turbulence, the effects of mean winds and shearsdue to pressure gradient on the turbulence decay was not considered.We propose to examine the effects of increasing geostrophic wind onthe convective boundary layer and its transition or decay to a stablecondition. Finally, the overall conclusions of each chapter will bepresented.
Cao, Qin Ph D. Massachusetts Institute of Technology. "Seismic imaging of the mantle transition zone." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70773.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references.
In this thesis, we developed a generalized Radon transform of SS precursors for large-scale, high-resolution seismo-stratigraphy of the upper mantle transition zone. The generalized Radon transform (GRT) is based on the single scattering approximation and maps singularities (reflections) in broad-band data into singularities (reflectors/scatters) in the medium. It is able to detect and characterize mantle discontinuities at a lateral resolution of several hundred kilometers. Synthetic tests with realistic source-receiver distributions demonstrate that the GRT is able to detect and image deep mantle interfaces at correct depths, even in the presence of noise, depth phases, phase conversions, and multiples generated by reverberation within the transition zone. We apply the GRT to ~1,600,000 broadband seismograms to delineate transition zone interfaces beneath distinct tectonic units, including a cross-section in the northwest Pacific Ocean that is far away from known down- and up-wellings, the volcanic islands of Hawaii, and the northwest Pacific subduction system. We account for smooth 3D mantle heterogeneity using first-order perturbation theory and independently derived global tomography models. Through integration with mineral physics data, the GRT seismic sections can put important constraints on the mantle temperature and mineralogy of the transition zone. Our GRT imaging results beneath the Central Pacific (including the Hawaii hotspot) reveal a more complicated mantle convection picture than a thin narrow vertical mantle "plume" passing through the transition zone. We found an 800- to 2000-kilometer-wide thermal anomaly (with a maximum temperature increase of -300 to 400 kelvin) deep in the transition zone west of Hawaii, by explaining the 410 and 660 km discontinuity topographies with olivine and garnet transitions in a pyrolitic mantle. According to our geodynamical modeling study of mantle upwellings, this might suggest that the hot materials feeding the Hawaii volcanoes do not rise from the lower mantle directly through a narrow vertical plume but may accumulate near the base of the transition zone before being entrained in flow toward Hawaii. In the GRT images of the subduction system, we found a deepened 660 km discontinuity in the slab that penetrates directly into the lower mantle according to tomography results. In another cross-section, where tomography results show that the slab is stagnant above the top of the lower mantle, we found broadening of the 660 km discontinuity signals at both edges of the slab. No corresponding uplift of the 410 km discontinuity is found. However, deepening of the 410 km discontinuity is observed beneath the continental side of the subduction system in both cross-sections, indicating hot anomalies at 410 km depth at the continental side if only the thermal effect is playing a role.
by Qin Cao.
Ph.D.
Lockhart, Matthew S. M. Massachusetts Institute of Technology. "A transit-timing variation study of the extrasolar planet TrES-3." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53108.
Повний текст джерелаIncludes bibliographical references (p. 105-106).
Portable Occultation Eclipse and Transit System (POETS) detectors [7] mounted on the Wallace Astrophysical Observatory (WAO) 0.8m and NASA Infrared Telescope Facility (IRTF) 3m telescopes are used to observe five stellar transit events of the extrasolar planet TrES-3 [5]. Model light curves are fit to the five data sets and transit midtimes are determined. Midtimes obtained in this study, along with midtimes reported by Sozzetti et al. (2008) [8], are compared to the ephemeris of the planet. The transit timing variation (TTV) of each midtime is calculated. Based on these data the presence of a third body in the TrES-3 system cannot be determined. Mass and period of a hypothetical perturbing body are calculated for several illustrative cases.
by Matthew Lockhart.
S.M.
Bowens-Rubin, Rachel (Rachel A. ). "Feasibility-study for space-based transit photometry using mid-sized nanosatellites." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/77872.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 85-88).
The photometric precision needed to measure a transit of small planets cannot be achieved by taking observations from the ground, so observations must be made from space. Mid-sized nanosatellites can provide a low-cost option for building an optical system to take these observations. The potential of using nanosatellites of varying sizes to perform transit measurements was evaluated using a theoretical noise budget, simulated exoplanet-transit data, and case studies to determine the expected results of a radial velocity followup mission and transit survey mission. Optical systems on larger mid-sized nanosatellites (such as ESPA satellites) have greater potential than smaller mid-sized nanosatellites (such as CubeSats) to detect smaller planets, detect planets around dimmer stars, and discover more transits in RV followup missions.
by Rachel Bowens-Rubin.
S.M.
Miles-Páez, Paulo A., Stanimir Metchev, Kevin L. Luhman, Massimo Marengo, and Alan Hulsebus. "The Prototypical Young L/T-Transition Dwarf HD 203030B Likely Has Planetary Mass." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/627091.
Повний текст джерелаOllander, Sandra. "Fler ekobyar, färre miljöproblem? : More ecovillages, less environmental problems?" Thesis, Malmö universitet, Malmö högskola, Institutionen för Urbana Studier (US), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-18441.
Повний текст джерелаTo solve sustainability problems we need to pay more attention to self sustainable societies with demand for less consumption, energy and transport as our lifestyle can not be combined with sustainability, climate-friendly and fair. Researchers and members of communities believe that the environmentally beneficial lifestyle that is associated with ecovillages and collective housing can contribute to reaching sustainable development goals and a sustainable lifestyle. A literature review and interviews were carried out with the purpose to investigate how ecovillages can help us live within the planetary boundaries and which social challenges ecovillages face. The results showed that ecovillages can help us to live within the planetary boundaries within six categories: ecological systems, ecological architecture, energy systems, transport systems, food systems and environmental friendly behaviour. Social challenges in ecovillages were leadership, decision making, undivided visions and goals, uneven balance of power, ethical questions, unemployment, organisation and different backgrounds.
Fruth, Thomas [Verfasser], and Heike [Akademischer Betreuer] Rauer. "Search for Planetary Transits and Stellar Variability with BEST II and ASTEP / Thomas Fruth. Betreuer: Heike Rauer." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2013. http://d-nb.info/1031511466/34.
Повний текст джерелаFredrich, Joanne Theresa. "Experimental study of the brittle to plastic transition in marble and diabase." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13752.
Повний текст джерелаVita.
Includes bibliographical references.
by Joanne Theresa Fredrich.
Ph.D.
Kelly, Amy E. (Amy Elizabeth) 1980. "Hydrocarbon biomarkers for biotic and environmental evolution through the Neoproterozoic-Cambrian transition." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/52763.
Повний текст джерелаThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references.
The sequence of events over the Neoproterozoic - Cambrian transition that led to the radiation of multicellular organisms has been an issue of debate for over a century. It is a critical interval in the history of life on Earth because it marks the first appearance of all extant animal phyla in the fossil record. We set out to improve understanding of environmental transitions during this key interval of Earth's history by studying chemical fossils (biomarkers) in Neoproterozoic to Cambrian aged sedimentary rocks and oils from Australia, Eastern Siberia and Oman. This thesis presents the distributions of steranes and other hydrocarbons through these various strata and the characterization of novel age and paleostratification biomarkers. Compound specific carbon isotopic data of n-alkanes and isoprenoids were also acquired and evaluated in the context of existing datasets with a focus on elucidating the processes responsible for anomalous trends. Consistent with current theory, our results indicate that there was a significant shift in the redox state the oceans and that this took place on a global scale. The biomarker and isotopic proxies we have measured help us further constrain the timing of this redox shift, and suggest a concomitant switch in the composition of marine photosynthetic communities, at termination of the Neoproterozoic Era.
by Amy Elizabeth Kelly.
Ph.D.
Whittaker, Gemma Nicole. "The analysis and removal of systematic trends in STEREO's HI-1A photometry and a search for planetary transits." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5054/.
Повний текст джерелаDe, Wit Julien. "Maps and masses of transiting exoplanets : towards new insights into atmospheric and interior properties of planets." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/95554.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (pages 183-200).
With over 1800 planets discovered outside of the Solar System in the past two decades, the field of exoplanetology has broadened our perspective on planetary systems. Research priorities are now moving from planet detection to planet characterization. In this context, transiting exoplanets-planets that cross in front of their star from our point-of-view-are of special interest due to the wealth of data made available by their orbital configuration. In this thesis, I introduce two methods, and their Markov chain Monte Carlo implementations, to gain new insights into the atmospheric and interior properties of exoplanets. The first method aims to map an exoplanet's atmosphere based on the eclipse scanning which is obtained while a planet is occulted by its host star. Ultimately temperature, composition, and circulation patterns could be constrained in three-dimensions from these maps, a significant asset for informing atmospheric models. I introduce the basics of eclipse mapping, its caveats (particularly, the correlation between the planet's shape, brightness distribution, and four system parameters), and a framework to mitigate the caveats' effects via global analyses including transits, phase curves, and radial velocity measurements. I use this method to create the first two-dimensional map and the first cloud map of an exoplanet for the hot-Jupiters HD 189733b and Kepler-7b, respectively. The second method, MassSpec, aims to determine transiting planet masses and atmospheric properties solely from transmission spectra, i.e. the starlight filtered by a planet's atmosphere during transits. Determination of an exoplanet's mass is key to understanding its basic properties, including its potential for supporting life. To date, mass constraints for exoplanets are predominantly based on radial velocity measurements, which are not suited for planets with low masses, large semi-major axes, or those orbiting faint or active stars. I demonstrate that a planet's mass has to be accounted for by atmospheric retrieval methods to ensure unbiased estimates of atmospheric properties. Utilizing MassSpec, the James Webb Space Telescope (launch date: 2018) could determine the mass and atmospheric properties of half a dozen Earth-sized planets in their host's habitable zones over its lifetime, which could lead to the first identification of a habitable exoplanet.
by Julien de Wit.
Ph. D. in Planetary Sciences
Cracchiolo, Gianluca. "Mitigation of the impact of stellar activity on observations of transiting planets." Doctoral thesis, Università degli Studi di Palermo, 2023. https://hdl.handle.net/10447/580043.
Повний текст джерелаThis thesis focuses on the quantification of the impact of stellar activity on observations of transiting planets and on the identification of a methodology to correct these effects. In particular, the role of starspots, both un-occulted and occulted is considered. The presence of spots on the visible stellar disk may distort the primary transit light curve in a wavelength-dependent way, mimicking the presence of an atmosphere. To take into account this bias, the thesis presents an innovative method to estimate the spots properties and their distribution from the out-of-transit observations and, on this basis, correct the planetary transit light curves, avoiding possible degeneracy between the presence of the planetary atmosphere and of the spots. The method is developed for low-resolution transit spectroscopy and is tested on realistic simulations of future observations of planetary transits with Ariel, a space mission dedicated to the observation of about 1000 transiting exoplanets whose launch is expected in 2029. Then, the method is applied to real observations of HST of a transiting planet. The first chapter of the thesis presents the state of the art of efforts done so far to mitigate the effect of the spots in planetary observations (chapter 1). Chapter 2 presents a method for correcting the effect of spots not-crossed by the transiting planet, starting from a basic model of the stellar activity, where the spotted star is simulated as a linear combination of stellar spectra at different temperatures and the star has a uniform emission. The method is tested on 3 simulated targets of transiting systems that will be observed by the Ariel mission. In Chapter 3, I introduced another component in the stellar model, making it more realistic. In fact, I simulate again the same targets analyzed in Chapter 2 but including the limb darkening effect to the stellar model. In this chapter, I show the importance of taking into account this effect if a good estimate of the spots’ parameters and a good correction of the planet's atmosphere have to be obtained. In Chapter 4 the approach presented in the previous chapters, and tested on simulations, is applied to observations of planetary transits of the planet LHS 1140 b, acquired with the Hubble Space Telescope. The analysis leads to two possible scenarios: in the first one the star is very active and almost the 65% of its surface is covered by spots (against other indicators in the literature suggesting a quiet star); in the second one, the star is quiet but is about 300 K cooler than in the first scenario. In both cases, the observed chromatic modulation derived from the planetary transit light curves is not due to the presence of a planetary atmosphere. In Chapter 5, I analyze the TESS light curves of the active star V1298 Tau, by modeling the star with a model dominated by 4 spots, co-rotating with the stellar surface. Such a study allows not only to derive the distribution of spots on V1298 Tau but also to correct the transit light curves of the 4 planets orbiting around the star for the effect of non-occulted spots. The results show that the spots’ effect may produce different transit depths for the 4 planets in the TESS and the K2 band, thus justifying the discrepancy between the planetary radii in the two bands reported in the scientific literature.
Neilson, Hilding R., Joseph T. McNeil, Richard Ignace, and John B. Lester. "Limb Darkening and Planetary Transits: Testing Center-to-limb Intensity Variations and Limb-darkening Directly from Model Stellar Atmospheres." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/2684.
Повний текст джерелаLamm, Rosalee Alicia. "Fine scale imaging of structures at and near the mantle transition zone using a generalized Radon transform." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37280.
Повний текст джерелаIncludes bibliographical references (p. 34-37).
We apply a generalized Radon transform (GRT) to the study of the transition zone discontinuities. The transition zone discontinuities, e.g. the '410' and '660', result from mineral phase changes that occur at depths constrained by temperature and chemistry, and can provide information about the conditions of the mantle within the transition zone. Previous global studies of topography on the transition zone discontinuities use SS data and are limited by the low lateral resolution provided by SS waves, on the order of about 1000 kilometers. The GRT employs inverse scattering theory to image perturbations in mass density and elastic parameters of a medium, and can resolve structure on the order of 100 kilometers; the limit of this resolution has yet to be tested. This study maps discontinuity depths in the northwest Pacific Ocean with a lateral spatial sampling of 1° and a vertical sampling of five kilometers. We observe striking variations in the depth, strength, and continuity of the '410', '520', and '660' seismic discontinuities, as well as the presence of structure beyond the bounds of what is traditionally considered to be the transition zone. Topographies on the '410' and '660' are alternately positively and negatively correlated, suggesting that both composition and temperature contribute to the observed depths. Preliminary analysis of '410' depths, which assumes no variations in chemistry, yields an upper bound for temperature variations of ±280K. Future tests and data preprocessing should further improve the GRT results.
by Rosalee Alicia Lamm.
S.M.
Pere, Christophe. "Étude de l’atmosphère de Vénus à l’aide d’un modèle de réfraction lors du passage devant le Soleil des 5-6 Juin 2012." Thesis, Université Côte d'Azur (ComUE), 2016. http://www.theses.fr/2016AZUR4063/document.
Повний текст джерелаThe transit of Venus across the Sun is a rare and unique opportunity to study therefraction of sunlight through the atmosphere, called the "aureola", and determine the atmosphericproperties of the planet and in particular the thermal structure of the upper atmosphere. Theobjective of this thesis was the modeling of this refraction effect at terminator during the passageacross the Sun which took place on June, 5-6 2012, and a comparison with data obtained in thesame region during the Venus Express mission.The first part is devoted to the analysis of data from an Earth-orbiting solar observatory thatallowed the creation of individual aureola light curves according to latitude, that were used as amodeling reference. The study of the refracting atmosphere was first carried out by an isothermalapproach (Baum and Code (1953) theory). The model was then refined by simulating threeconcentric layers based on prior analysis of Venus Express/SPICAV-SOIR vertical density profiledata obtained simultaneously on June 6, 2012. Finally, the complete model developed for thisstudy is a concentric layered model with sub-kilometer vertical resolution. This model has allowedus to retrieve from individual aureole lightcurves a density vertical profile function of the latitudeand the tau = 1 altitude of slanted opacity along the line of sight, induced by mesospheric aerosols.These data were subsequently used to generate temperature maps in 2D function of latitude andaltitude, we compare the solar occultation data from the Venus Express mission (SOIR). This studyalso determined independently the scale height of aerosols and the chromaticity in the atmosphereof Venus.A separate, additional study on 2004 Venus transit data was conducted jointly with Dr.Andrea Chiavassa to highlight the impact of the stellar granulation on exoplanetary transit curves inextrasolar systems
Burke, Christopher J. "Survey for transiting extrasolar planets in stellar systems stellar and planetary content of the Open Cluster NGC 1245 /." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1132168623.
Повний текст джерелаZellem, Robert Thomas. "Observing Transiting Exoplanets: Removing Systematic Errors To Constrain Atmospheric Chemistry And Dynamics." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556734.
Повний текст джерелаLee, Jae Min. "Retrieval of atmospheric structure and composition of exoplanets from transit spectroscopy." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:9daa5af9-040d-47eb-a2ca-57aefcc36f21.
Повний текст джерелаZhou, G., G. Á. Bakos, J. D. Hartman, D. W. Latham, G. Torres, W. Bhatti, K. Penev, et al. "HAT-P-67b: An Extremely Low Density Saturn Transiting an F-subgiant Confirmed via Doppler Tomography." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/623926.
Повний текст джерелаPepper, Joshua Aaron. "KELT the Kilodegree Extremely Little Telescope /." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1179852674.
Повний текст джерелаLyda, Andrew W. "Normal Fault Trace-Length Scaling in a Tectonic Transition Zone in Southern Sedna Planitia, Venus." Wright State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=wright1365612940.
Повний текст джерелаEscobar, David. "Mémoire et édition pendant la transition démocratique espagnole : la collection "Espejo de España" des Editions Planeta de 1973 à 1978." Bordeaux 3, 2008. http://www.theses.fr/2008BOR30044.
Повний текст джерелаThe collection entitled “Espejo de España”, which was created in 1973 by literary director Rafael Borràs Betriu on behalf of Planeta Publishings, came up to the specific expectations of the readership of that time. This collection was issued in the publishing market while the Francoist dictatorship was drawing to a close and major political events were about to emerge. Within this context, in the aftermath of a dictatorship whose main concern had been the preservation of a one-sided official memory, the volumes of the collection “Espejo de España” shed a more balanced light on the immediate history of the country, which was made possible both by a less severe censorship and by force of circumstances. In this respect, these books provide the reader with a real insight into the democratic transition and allow a better grasp of its historical scope. However, this collection is the outcome of an intellectual path initiated by Rafael Borràs in the book world in the middle of the fifties. He first created “La Jirafa”, a cultural review with an open-minded outlook, and then went on to work successively within several publishing houses, which allowed him to refine his projects focused on the recuperation of a past proscribed by the dictatorship. Furthermore, the outcome of “Espejo de España” can only be fully grasped through the objective alliance of two complementary dynamics. The collection came to light in Planeta Publishing and was therefore furthered by a publishing house which was economically prosperous. What is more, this collection was supported in a relatively autonomous way by his director Rafael Borràs who was then able to issue it on a fairly large scale
Bruno, Giovanni. "Characterization of transiting exoplanets : analyzing the impact of the host star on the planet parameters." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4746/document.
Повний текст джерелаDuring my PhD, I analyzed the spectra of nine Kepler stars obtained by radial velocity (RV) observations. This allowed the characterization of their planetary companions. I analyzed the spectra of twenty-one other CoRoT and Kepler stars, likely orbited by low-mass M dwarfs. This helped widening the sample of low-mass stars with measured mass and radius. I calculated the chromospheric activity indfex of thirty-one stars observed with SOPHIE/OHP, helping the study of star-planet interactions. I studied the behavior of SOPHIE in low signal-to-noise ratio (SNR) regime. I determinhed the SNR range in which a stellar spectrum is reliable for the measure of the stellar parameters.Within the SOPHIE consortium, I followed the complete analysis of the Kepler-117 system. This multi-planetary system presents variations in the planetary orbital periods due to their mutual dynamical interacion (TTVs). To fit the system parameters, a specific fitting approach including TTV modeling was developed. We derived the system parameters by the simultaneous fit of transits, RVs, and TTVs (Bruno et al. 2015).Finally, I addressed the problem of stellar activity in transit photometry. I implemented two starspot modeling codes into an MCMC algorithm, adding spot evolution to oneof them. I applied the codes to the Sun, CoRoT-7, and CoRoT-2. I carried an extensive study on the light curve of CoRoT-2, and explored the effects of the spots on the transit parameters (Bruno et al., in prep.). With the FF’ method (Aigrain et al. 2012), I contributed to explore the connection between the photometric and RV signature of starspots in CoRoT-7
Fogliardi, Michele. "Proprietà generali dei pianeti del sistema solare e ricerca di pianeti esterni." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21236/.
Повний текст джерелаMichel, Nathalie. "Modélisation de l'évolution thermique de Mars : conséquences sur le champ magnétique." Phd thesis, Université Paul Sabatier - Toulouse III, 2011. http://tel.archives-ouvertes.fr/tel-00572876.
Повний текст джерелаBordé, Pascal. "Recherche des exoplanètes, mesure de leurs propriétés physiques et orbitales." Habilitation à diriger des recherches, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00917762.
Повний текст джерелаSandford, Emily Ruth. "The Shapes of Planet Transits and Planetary Systems." Thesis, 2020. https://doi.org/10.7916/d8-jqt7-9a41.
Повний текст джерелаLin, Yi-Ling, and 林怡伶. "The Observations and Analysis of Transit Events In the XO-1 Planetary System." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/57166637360335136176.
Повний текст джерела國立清華大學
天文研究所
102
We observed two newly transits of the XO-1 planetary system. The observations of one of these transit events are done by using the 46-cm telescope hosted by Wise Observatory in Israel. The observations of the other one are done by using both 104-cm and 130-cm telescopes located at ARIES in India. We investigate the possibility for the transit timing variations (TTVs) in the orbital period of XO-1b that may aroused by the existents of an additional planet in this system, so we collected 28 transits from public data and analyzed with our own data. After the O-C diagram of the XO-1 system is obtained and analyzed, we found that a null TTV produces a fit with χred2=2.1764. We also find that the ephemeris with a sinusoidal function of a frequency 0.483985 has a fit with χred2=1.7962 and the one of a frequency 0.10706 has a fit with χred2=2.0867.
Johnson, Marshall Caleb. "Doppler tomographic observations of exoplanetary transits." 2013. http://hdl.handle.net/2152/21310.
Повний текст джерелаtext
Molinié, Roxana. "Experiencia de la desaparición en Lumpérica de Diamela Eltit, Los planetas de Sergio Chejfec y Los rubios de Albertina Carri." Thèse, 2014. http://hdl.handle.net/1866/12018.
Повний текст джерелаThis thesis analyzes how Diamela Eltit’s Lumpérica (1983), Sergio Chejfec’s Los planetas (1999), and Albertina Carri’s Los rubios (2003) articulate the experience of the loss of experience resulting from the dictatorships and post-dictatorships in Chile and Argentina. The last military dictatorships in the Southern Cone either impose or prepare the ground for the establishment of a new neoliberal order that deepens and intensifies with later democratic regimes. In this transition, the military governments deploy strategies of State terrorism that aim to eliminate all forms of resistance to the social reconfiguration necessary for the implementation of neoliberal politics, giving rise to an unprecedented kind of experience that is difficult to communicate. Moreover, both the dictatorships and the post-dictatorial democracies adopt strategies of forgetting, through either repression, political consensus or mass media communications. It is in this context that experience disappears. The discussion on experience of the loss of experience is based mainly on the concept of transition from State to Market in Latin America’s Southern Cone developed by thinkers such as Willy Thayer, Idelber Avelar or Brett Levinson, among others, as well as on Sergio Rojas’s considerations on dictatorial experience and on Walter Benjamin’s reflections on the crisis of experience in modern life. The first chapter, dedicated to Lumpérica, analyzes a nocturnal ritual where the protagonist, a woman named L. Iluminada, seduces the male protagonist, an electric billboard called “el luminoso” that projects publicity messages in the middle of a public square in Santiago; she hopes to make him wound and mark her skin, staging a “photographic desire” to keep a trace of the transition that other media push towards forgetting and erasure. The second chapter focuses on the figuration of excess in Los planetas, analyzing how writing, photography and urban space act as supplements to the voice and to the presence of M, a young man who disappeared during the Argentinian dictatorship, thus accounting for the loss of experience. After revisiting the debate incited by Los rubios, much of which centred on the film’s polemic use of toys, the third chapter analyzes how Carri’s film about the memory of her disappeared parents transmits the experience of post-dictatorial generations and confronts the heritage of the past through play.
En esta tesis se analiza la articulación de la experiencia de la pérdida de experiencia a la que dan lugar las dictaduras y las postdictaduras en Chile y Argentina, en Lumpérica (1983) de Diamela Eltit, Los planetas (1999) de Sergio Chejfec, y Los rubios (2003) de Albertina Carri. Las últimas dictaduras militares en el Cono Sur imponen o preparan el terreno para la implantación de un nuevo orden neoliberal que se intensifica durante los regímenes democráticos posteriores. En esta transición, el terrorismo de Estado mediante el cual los gobiernos militares buscan eliminar toda forma de resistencia a la reconfiguración de la sociedad que requiere la implementación de las políticas neoliberales, da lugar a una experiencia inédita, difícil de comunicar. Por otro lado, tanto las dictaduras como las democracias postdictatoriales ponen en marcha mecanismos de olvido del pasado, ya sea mediante la represión, el consenso político o los medios de comunicación de masas. Es en este contexto que la experiencia desaparece. Las premisas teóricas en que se basa el cuestionamiento sobre la experiencia de la pérdida de experiencia son el concepto de transición del Estado al Mercado en el Cono Sur latinoamericano desarrollado por intelectuales como Willy Thayer, Idelber Avelar o Brett Levinson, entre otros, así como las reflexiones sobre la experiencia dictatorial de Sergio Rojas y sobre la crisis de la experiencia en la modernidad de Walter Benjamin. El primer capítulo, dedicado a Lumpérica, interpreta el ritual nocturno en el que la protagonista, una mujer llamada L. Iluminada, seduce al protagonista masculino de la novela, un cartel eléctrico llamado “el luminoso” que proyecta avisos comerciales en el centro de una plaza de Santiago, para que este la hiera y marque su piel, como la puesta en escena de un “deseo fotográfico” de guardar una huella de la transición que otros medios tienden a borrar. El segundo capítulo enfoca la figuración del exceso en Los planetas y analiza cómo la escritura, la fotografía y el espacio urbano, al adquirir en la novela una función de suplementos de la palabra viva y de la presencia de M, secuestrado y desaparecido durante la dictadura argentina, dan cuenta de la experiencia de la pérdida de la experiencia de una plenitud. Después de exponer el rol de los juguetes en la polémica generada por Los rubios, el tercer capítulo analiza cómo el film de Carri sobre la memoria de sus padres montoneros desaparecidos transmite la experiencia de las generaciones postdictatoriales y se enfrenta al legado del pasado mediante el juego.
Petrucci, Romina Paola. "Estudio de variaciones en los tiempos de mínimo en estrellas con planetas transitantes del Hemisferio Sur." Doctoral thesis, 2015. http://hdl.handle.net/11086/2868.
Повний текст джерелаEn este trabajo presentamos los resultados del monitoreo y análisis homogéneo de tránsitos de planetas que orbitan alrededor de estrellas del Hemisferio Sur. El propósito principal de este seguimiento fotométrico es el de buscar variaciones en los tiempos de mínimo (TTVs) que pudieran atribuirse a la presencia de otros cuerpos de masa planetaria no detectados, ligados gravitacionalmente al sistema. Para ello realizamos observaciones con los telescopios argentinos Horacio Ghielmetti (THG) de 40 cm localizado en el Complejo Astronómico El Leoncito (CASLEO) y el telescopio de 1.54 m ubicado en la Estación Astrofísica de Bosque Alegre (EABA). Dado que se requieren muchos datos para llevar a cabo análisis de TTVs confiables, sólo estudiamos las 3 estrellas de nuestra muestra inicial que presentaron más de 10 observaciones entre propias y extraídas de la literatura. Como subproducto del análisis de variaciones en los tiempos de mínimo, para cada uno de nuestros objetos computamos nuevas efemérides y re-determinamos los parámetros físicos de la estrella y el planeta. Considerando que los puntos analizados comprenden como mínimo 3 años de observaciones, además de estudiar las variaciones a largo plazo de los tiempos de mínimo, evaluamos las variaciones en la inclinación de la órbita (i) y la profundidad del tránsito (k) que también pudieran atribuirse a la presencia de otro cuerpo de masa planetaria en el sistema.
Шмиков, Євген Олегович. "Удосконалення конструкції планетарного приводу кривошипного пресу". Магістерська робота, 2020. https://dspace.znu.edu.ua/jspui/handle/12345/2733.
Повний текст джерелаUA : В роботі обґрунтовано переваги використання приводу, встановлені основні закономірності руху ланок в період вмикання та зупинки, визначені навантаження на них та витрати енергії. Використання привода забезпечує зниження загальної ваги преса, усувається проміжна передача в багатоступеневому приводі, знижуються витрати роботи на вмикання порівнюючи з фрикційними муфтами.
EN : The work substantiates the advantages of using a drive, establishes the basic laws of link movement during the start and stop periods, certain loads on them and energy consumption. The use of the drive reduces the total weight of the press, eliminates the intermediate gear in a multi-stage drive, reduces the cost of the work on the inclusion compared with friction clutches.