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Light Echoes and Late-Time Emissions of Type IA Supernovae Dina Drozdov Clemson University, [email protected]

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Light Echoes and Late-Time Emissions of Type IA Supernovae Dina Drozdov Clemson University, Ddrozdo@G.Clemson.Edu Clemson University TigerPrints All Dissertations Dissertations 5-2016 Light Echoes and Late-Time Emissions of Type IA Supernovae Dina Drozdov Clemson University, [email protected] Follow this and additional works at: https://tigerprints.clemson.edu/all_dissertations Recommended Citation Drozdov, Dina, "Light Echoes and Late-Time Emissions of Type IA Supernovae" (2016). All Dissertations. 1639. https://tigerprints.clemson.edu/all_dissertations/1639 This Dissertation is brought to you for free and open access by the Dissertations at TigerPrints. It has been accepted for inclusion in All Dissertations by an authorized administrator of TigerPrints. For more information, please contact [email protected]. Light Echoes and Late-Time Emissions of Type Ia Supernovae A Dissertation Presented to the Graduate School of Clemson University In Partial Fulfillment of the Requirements for the Degree Doctorate of Philosophy Physics by Dina Drozdov May 2015 Accepted by: Dr. Mark D. Leising, Committee Chair Dr. Dieter Hartmann Dr. Jeremy King Dr. Catalina Marinescu Abstract Type Ia supernovae have many applications in astronomy, yet with fundamental properties still not fully understood, new methods for investigating the environment of a supernova need to be developed. A light echo is produced from the scattering of light from a bright source and can be used to analyze the dust in the vicinity of the supernova and learn invaluable information about the source. These techniques can put constraints on explosion and progenitor models. Although light echo detections from Type Ia supernovae are rare, with only seven total extragalactic detections, this could be due to the lack of thorough late-epoch monitoring. Since key information is determined from even a single light echo detection, light echo searches should be undertaken in the future to supplement our understanding of supernovae. As part of our collaborative campaign for studying the emission of supernovae at late epochs, we have added two light echoes to a small sample size of Type Ia supernova light echo detections: SN 2009ig in NGC 1015 and a dual echo from SN 2007af in NGC 5584. Both echoes were observed with the Hubble Space Telescope and allow for the most detailed images of Type Ia supernova light echoes to date. Three filters (F555W, F814W, and F350LP) captured the echoes obtained with the Wide Field Camera 3, and since both host galaxies were imaged as part of the same observing program, these cases will be the best comparable light echo pairs. We also further investigate the light echoes from SN 2006X in NGC 4321 and SN 1998bu in NGC 3368 from Hubble Space Telescope archival images. Analyses performed on the images gives crucial insight into the dusty environment of the host galaxy and the surroundings of the supernova. The outer echo from SN 2007af was created from an interstellar dust sheet located ∼800 pc in front of the supernova, while the inner echo could be from interstellar or circumstellar origin. A circumstellar light echo could imply a single degenerate progenitor. The dust is closer to the supernova for the echo in SN 2009ig. Exploring the color of the ii echoes gives implications on the dust type, and both light echo cases have atypical color evolution from model predictions, which suggests abnormal dust is involved. The echoes from SN 2006X and double echo from SN 1998bu show the evolution of the echoes over a long time period, which can be compared to past findings by multiple teams. The echoes show remarkable similarity to other Type Ia echo detections, and with more discoveries, the transition of light echoes from normal emission can be investigated, which could further probe the supernova ejecta. Using a process we developed, we calculate the magnitude differences between Hubble Space Telescope and standard filters in the case of normal supernovae. We conclude by comparing all light echo detections to date and discussing the future goals of this work. iii Table of Contents Title Page ............................................ i Abstract ............................................. ii List of Tables .......................................... vi List of Figures..........................................viii 1 Introduction......................................... 1 1.1 Late-Epoch Behavior of Type Ia Supernovae....................... 2 1.2 Light Echoes in Type Ia Supernovae........................... 3 1.3 Light Echoes as Tools ................................... 5 2 SN 2007af ..........................................15 2.1 Ground-based Observations................................ 15 2.2 Space-based Observations................................. 20 2.3 Physical Model....................................... 28 3 SN 2006X ..........................................36 3.1 Early Epoch Observations and Reductions........................ 37 3.2 HST Observations ..................................... 41 3.3 Light Echo Geometry ................................... 46 3.4 Dust Analysis........................................ 49 4 SN 1998bu..........................................58 4.1 Early Observations..................................... 59 4.2 Light Echo Observations.................................. 61 4.3 Photometry......................................... 68 4.4 Dust Analysis........................................ 69 5 SN 2009ig ..........................................85 5.1 Early Observations..................................... 85 5.2 Steward and Kitt Peak Observations........................... 91 5.3 Light Echo Observations.................................. 92 5.4 Dust Analysis........................................ 96 6 Comparisons.........................................102 6.1 SN 1991T vs. SN 1998bu ................................. 103 6.2 SN 2007af vs. SN 1998bu ................................. 106 6.3 All SN Ia Light Echoes................................... 107 7 Conclusions .........................................110 iv 7.1 Future Work ........................................ 113 Appendices ...........................................117 A Ground- Versus Space-Based Filter Differences ..................... 118 v List of Tables 2.1 Optical Photometry from Steward Observatory..................... 16 2.2 Angular Sizes of Echoes .................................. 26 2.3 HST Photometry Parameters............................... 27 2.4 Light Echo Magnitudes .................................. 28 2.5 Dust Sheet Distances.................................... 29 2.6 Dust Parameters ...................................... 31 2.7 Color Values ........................................ 31 3.1 Early Epoch Optical Observations ............................ 38 3.2 Early Epoch Optical Observations Continued...................... 39 3.3 CSP Early Epoch Optical Observations ......................... 40 3.4 Early Epoch Optical Observations ............................ 41 3.5 Light Echo Photometry Comparisons........................... 45 3.6 Angular Size Comparisons................................. 50 3.7 Dust Sheet Distances.................................... 50 3.8 Magnitude Change Values................................. 52 3.9 Optical Depth of Dust................................... 52 3.10 SN 2006X Color Evolution................................. 55 3.11 SN 2006X B { V Light Echo Color Predictions..................... 56 3.12 SN 2006X Light Echo V { I Color Predictions ..................... 56 3.13 SN 2006X Filter Differences................................ 57 4.1 Early Optical Observations ................................ 60 4.2 Optical Observations.................................... 62 4.3 Optical Observations Continued.............................. 63 4.4 Further SN 1998bu Optical Observations ........................ 64 4.5 HST SN 1998bu Observations............................... 66 4.6 SN 1998bu Light Echo Photometry ........................... 72 4.7 SN 1998bu Outer Echo Sizes and Dust Distances.................... 76 4.8 SN 1998bu Inner Echo Sizes and Dust Distances .................... 76 4.9 Dust Sheet Inclination Evolution............................. 77 4.10 Peak Photometry Magnitudes............................... 80 4.11 Magnitude Change Values................................. 80 4.12 Optical Depth of Dust................................... 81 4.13 SN 1998bu Filter Differences ............................... 83 4.14 HRC Light Echo Color Predictions............................ 83 4.15 2009 Light Echo Color Predictions ............................ 83 4.16 2014 Light Echo Color Predictions ............................ 84 5.1 KAIT Observations..................................... 87 5.2 KAIT Observations Continued .............................. 88 vi 5.3 Swift/UVOT Observations................................. 88 5.4 Peak Color Information .................................. 88 5.5 Steward and Kitt Peak Observations........................... 93 5.6 LBT Observations ..................................... 93 5.7 HST Observations ..................................... 94 5.8 SN 2009ig Light Echo V { I Color Predictions ..................... 101 5.9 SN 2009ig Filter Differences................................ 101 6.1 SN 1991T vs. SN 1998bu Light Echo Magnitudes.................... 103 6.2 SN Ia Light Echo Detections ............................... 107 6.3 SN Ia Light Echo Comparisons .............................. 109 1 WFC3 { Bessell Filter Differences............................. 118 2 WFC3 { Johnson-Cousins Filter Differences....................... 121 3 WFC3 { Str¨omgrenFilter
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