In this Thesis, I explore transiting exoplanets: what we can learn from modeling their light curves, and what we can learn from their arrangement in planetary systems. I begin in Chapter 1 by briefly reviewing the history of transit modeling, from the earliest theoretical models of eclipsing binary stars to the models in current widespread use to model exoplanet transits. In Chapter 2, I model the transits of a sample of Kepler exoplanets with strong prior eccentricity constraints in order to derive correspondingly strong constraints on the density of their host stars, and find that the density constraints I derive are as precise as density constraints from asteroseismology if the transits are observed at high signal-to-noise. In Chapter 3, I apply the same methodology in reverse: using prior knowledge of the stellar density based on Gaia parallax measurements, I model the transits of twelve singly-transiting planets observed by K2 and derive constraints on their periods. In Chapter 4, I consider the general problem of deducing the shape of a transiting object from its light curve alone, which I term ``shadow imaging;'' I explore the mathematical degeneracies of the problem and construct shadow images to explain Dips 5 and 8 of Boyajian's Star. I next turn to multi-planet systems: in Chapter 5, I investigate the underlying multiplicity distribution of planetary systems orbiting FGK dwarfs observed by Kepler. I find that we can explain the multiplicities of these systems with a single Zipfian multiplicity distribution, without invoking a dichotomous population. In Chapter 6, I consider the arrangement of planets in those systems, and use neural networks inspired by models used for part-of-speech tagging in computational linguistics to model the relationship between exoplanets and their surrounding "context," i.e. their host star and sibling planets. I find that our trained regression model is able to predict the period and radius of an exoplanet to a factor of two better than a naive model which only takes into account basic dynamical stability. I also find that our trained classification model identifies consistent classes of planets in the period-radius plane, and that it is rare for multi-planet systems to contain a neighboring pair of planets from non-contiguous classes. In Chapter 7, I summarize these results and briefly discuss avenues for future work, including the application of our methods to planets and planetary systems discovered by TESS.

At this moment there is a gap in information regarding the affect roots might have on 210Pb distribution in peat cores and in turn the obtained chronologies by 210Pb dating. Therefore, four peat cores were collected from the snow manipulation study site within the mire complex Storflaket (68°20048″N, 18°58016″E). Two cores from snow fence plots, which has experienced root growth due to permafrost thaw, and 2 cores from control plots. 210Pb distribution and the provided 210Pb chronologies were then compared with root content within and between the cores. In two of the cores (C5 and SF2) did subsurface peaks in the 210Pb activity profile follow the distribution profile of the dwarf shrub roots. The same pattern was not seen with Eriophorum roots. This indicates that presence of dwarf root with their shallow and horizontally growth can affect the 210Pb profile by horizontal translocation of 210Pb. The chronologies obtained by the CF:CS and CRS dating models could not be validated for the C5 core which suggest that dwarf shrub roots also can affect the 21oPb dating.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21572号 / 理博第4479号 / 新制||理||1643(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 野上 大作, 教授 長田 哲也, 教授 嶺重 慎 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

京都大学 / 新制・課程博士 / 博士(理学) / 甲第23014号 / 理博第4691号 / 新制||理||1673(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 野上 大作, 教授 嶺重 慎, 教授 太田 耕司 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

This thesis deals with an introduction to debugging and debuggers. The thesis describes principles of the debugging information, especially the DWARF format and its Call Frame Information (CFI), that enables a debugger to visualize the call stack. Furthermore, extensions of the debugger used in the Lissom project were designed and implemented. These extensions added support for call stack visualization, history value storage and step return and step over commands.

No description available.

M dwarf stars make up over 70% of stars by number in the Milky Way Galaxy and are known to host at least two exoplanets per star on average. Using mutually eclipsing double-lined spectroscopic binary stars (SB2 EBs), astronomers can empirically measure stellar properties of M dwarf stars including mass and radius. However, empirical measurements systematically differ from the predictions of stellar evolutionary models and show large scatter. Some M dwarf stars are outliers, with radii that are a factor of 2-to-3 larger than model predictions, assuming they were measured accurately. In this dissertation, I investigated whether the outliers, systematic offset, and the scatter seen in the mass-radius diagram are physical, using SB2 EBs with photometry from NASA's Kepler Mission and high-resolution near-infrared ground-based spectroscopy. Empirical measurements using space-based photometry and high-resolution near-infrared ground-based spectroscopy, together with Bayesian model-fitting techniques, provide significant advancements over previous measurements. For this dissertation work, a sample of Kepler EBs were carefully chosen to be detached and non-interacting. I conducted a radial velocity survey of the sample using Immersion GRating INfrared Spectrometer (IGRINS) with the Discovery Channel Telescope (DCT) and iSHELL with NASA's Infrared Telescope Facility (IRTF). Combined with high-precision Kepler data, I determined the masses and radii of the component stars in the sample. I also determined a new mass-radius relationship of M dwarf stars using the sample of Kepler EB systems. My investigation showed that the outliers in the mass-radius diagram of M dwarf stars are not physical and they are due to the quality of data and from analysis using different pipelines. I also showed that the offset and scatter in the mass-radius diagram are persistent, which are not from the measurement uncertainties. This suggests the need for an extra degree of freedom to accurately capture the discrepancies between the empirical measurements and model predictions. Lastly, I showed that reduced convective heat flow due to enhanced magnetic fields from rapid stellar rotation can account for the offset and scatter in the measurements.

Final thesis was worked out on theme Aplication of cryotherapy as a tool for plant viruses eradication from Prunus persica (L.) Batsch regenerants. Experiment was conducted on Faculty of Agronomy of the Mendel University in Brno and in the Crop Research Institute in Prague-Ruzyně. Literary research describes information about peach cultivation in vitro and plant pathogen eradication by cryotherapy. These information has been used in practical part of the final thesis. Plant material of the ´Redhaven´variety of peach was used for virus eradication by cryotherapy. Cryotherapy was applied on shoot tips. In the end of final thesis shoot tips viability and regeneration were evaluated.

At this moment there is a gap in information regarding the affect roots might have on 210Pb distribution in peat cores and in turn the obtained chronologies by 210Pb dating. Therefore, four peat cores were collected from the snow manipulation study site within the mire complex Storflaket (68°20048″N, 18°58016″E). Two cores from snow fence plots, which has experienced root growth due to permafrost thaw, and 2 cores from control plots. 210Pb distribution and the provided 210Pb chronologies were then compared with root content within and between the cores. In two of the cores (C5 and SF2) did subsurface peaks in the 210Pb activity profile follow the distribution profile of the dwarf shrub roots. The same pattern was not seen with Eriophorum roots. This indicates that presence of dwarf root with their shallow and horizontally growth can affect the 210Pb profile by horizontal translocation of 210Pb. The chronologies obtained by the CF:CS and CRS dating models could not be validated for the C5 core which suggest that dwarf shrub roots also can affect the 21oPb dating.

We have used the Hubble STIS and FUSE archives of ultraviolet spectra of bright AGNs to identify intergalactic Lya absorbers in nearby (z ≤ 0.1) voids. From a parent sample of 651 Lyα absorbers, we identified 61 "void absorbers" located >1.4 h70-1 Mpc from the nearest L* or brighter galaxy. Searching for metal absorption in high-quality (S/N > 10) spectra at the location of three diagnostic metal lines (O VI λ1032, C IV λ1548, Si III λ1206), we detected no metal lines in any individual absorber, or in any group of absorbers using pixel co-addition techniques. The best limits on metal-line absorption in voids were set using four strong Lya absorbers with NHI > 1014 cm-2, with 3 σ equivalent-width limits ranging from 8 mÅ (O VI) to 7-15 mÅ (C IV) and 4-10 mÅ (Si III). Photoionization modeling yields metallicity limits Z < 10 -1.8±0.4 Z⊙ from nondetections of C IV and VI, some ∼6 times lower than those seen in Lyα/O VI absorbers at z < 0.1. Although the void Lyα absorbers could be pristine material, considerably deeper spectra are required to rule out a universal metallicity floor produced by bursts of early star formation, with no subsequent star formation in the voids. The most consistent conclusion derived from these low-z results and similar searches at z = 3-5 is that galaxy filaments have increased their mean IGM metallicity by factors of 30-100 since z ∼ 3.