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The Kinematics of Massive Stars and Circumstellar Material in the Carina Nebula

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The Kinematics of Massive Stars and Circumstellar Material in the Carina Nebula The Kinematics of Massive Stars and Circumstellar Material in the Carina Nebula Item Type text; Electronic Dissertation Authors Kiminki, Megan Michelle Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 04/10/2021 12:24:30 Link to Item http://hdl.handle.net/10150/625635 THE KINEMATICS OF MASSIVE STARS AND CIRCUMSTELLAR MATERIAL IN THE CARINA NEBULA by Megan Michelle Kiminki Copyright c Megan Michelle Kiminki 2017 A Dissertation Submitted to the Faculty of the DEPARTMENT OF ASTRONOMY In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY WITH A MAJOR IN ASTRONOMY AND ASTROPHYSICS In the Graduate College THE UNIVERSITY OF ARIZONA 2017 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the disser- tation prepared by Megan Michelle Kiminki, titled The Kinematics of Massive Stars and Circumstellar Material in the Carina Nebula and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy. Date: 27 June 2017 Nathan Smith Date: 27 June 2017 Daniel Marrone Date: 27 June 2017 Kaitlin Kratter Date: 27 June 2017 Catharine Garmany Date: 27 June 2017 Marcia Rieke Final approval and acceptance of this dissertation is contingent upon the candidate’s submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. Date: 27 June 2017 Dissertation Director: Nathan Smith 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of the requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that an accurate acknowledgement of the source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED: Megan Michelle Kiminki 4 ACKNOWLEDGEMENTS This dissertation would not exist without the invaluable guidance and encourage- ment of my advisor, Nathan Smith. Thank you for taking on a nervous third-year with an interest in massive stars. I would also like to thank the members of my committee: Dan Marrone, for a listening ear when I needed it; Katy Garmany, for jumping in with extraordinary enthusiasm; Kaitlin Kratter, for the single most useful tip on writing an introduction; Marcia Rieke, for helping out at the last minute; George Rieke, for the advising that got me through my prelim; and Josh Eisner, who also couldn’t be there at the end but offered support along the way. We would all have been lost without the tireless work of Michelle Cournoyer, program coordinator extraordinaire. Many thanks are owed to my collaborators and most especially to Megan Reiter, who—among many other things—reminded me that talking science can be fun. I will be forever grateful to Jay Anderson for sharing his code and teaching me the secrets of aligning HST images. I am also indebted to the Yale SMARTS team, particularly Emily MacPherson, for scheduling my CHIRON observations, and the telescope operators at CTIO who carried out those observations. Thank you to my fellow Steward grad students for your friendship and support. Michelle Wilson, office- and trailer-mate—we made it! Vanessa Bailey and Amanda Ford were there when the going got rough. Kate Follette has been an amazing role model and landlord. Johanna Teske’s enthusiasm about all my endeavors, both inside and outside of academia, helped so much. And Nick Ballering introduced me to BibTeX, which no dissertation-writer should ever have to do without. Thank you to my dad, for reading all my papers, and to my mom, for always being proud of me. Most of all, thank you to Dan, the most wonderful partner anyone could ever ask for. Support for the research in this dissertation was provided by NASA grants GO- 13390 and GO-13791 from the Space Telescope Science Institute, which is oper- ated by the Association of Universities for Research in Astronomy (AURA) under NASA contract NAS 5-26555. This work is based on observations made with the NASA/ESA Hubble Space Telescope and obtained from the Data Archive at the Space Telescope Science Institute, and on observations made at Cerro Tololo Inter- American Observatory, National Optical Astronomy Observatory (NOAO Proposal IDs 2014B-0235 and 2015B-0141), which is operated by AURA under a cooperative agreement with the National Science Foundation. 5 DEDICATION For Dan, my strength. For Ian, my joy. For the one on the way. 6 TABLE OF CONTENTS LISTOFFIGURES ................................ 8 LISTOFTABLES ................................. 9 ABSTRACT .................................... 10 CHAPTER1 INTRODUCTION . .. .. 11 1.1 FeedbackfromMassiveStars. 12 1.1.1 Feedbackmechanisms. 12 1.1.2 Triggered star formation . 19 1.2 TheCarinaNebula ............................ 21 1.2.1 Structure and stellar content . 22 1.2.2 The luminous blue variable η Carinae.............. 27 1.3 OBAssociations.............................. 30 1.4 Dissertation Overview . 33 CHAPTER 2 ANCIENT ERUPTIONS OF η CARINAE: A TALE WRITTEN INPROPERMOTIONS............................ 34 2.1 Introduction................................ 35 2.2 Observations and Analysis . 38 2.2.1 HST ACS............................. 38 2.2.2 HST WFPC2........................... 42 2.2.3 Position of the central source . 46 2.3 Results................................... 46 2.3.1 HST proper motions over two decades . 46 2.3.2 Agesoftheouterejecta . 50 2.3.3 Asymmetry and the most distant ejecta . 57 2.4 Discussion................................. 59 2.4.1 Comparison to radial velocities . 59 2.4.2 Relationship to X-ray emission and the extremely fast ejecta . 59 2.4.3 Alternate ejection histories . 62 2.4.4 Implications for models of η Car................. 64 2.5 Conclusions ................................ 65 7 TABLE OF CONTENTS – Continued CHAPTER 3 PROPER MOTIONS OF FIVE OB STARS WITH CANDI- DATE DUSTY BOW SHOCKS IN THE CARINA NEBULA . 67 3.1 Introduction................................ 68 3.2 Observations and Analysis . 73 3.2.1 HST ACSimaging ........................ 73 3.2.2 Image alignment and stacking . 75 3.2.3 Measuring local proper motions of saturated stars . 76 3.3 Results................................... 80 3.4 Discussion................................. 85 3.4.1 Proper motions as upper limits . 85 3.4.2 Comparison to absolute proper motions . 87 3.4.3 Interpreting bow shocks in giant H II regions . 91 3.4.4 Implications for the origins of OB associations . 93 3.5 Conclusions ................................ 94 CHAPTER 4 A RADIAL VELOCITY SURVEY OF THE CARINA NEB- ULA’SO-TYPESTARS ............................ 95 4.1 Introduction................................ 96 4.2 ObservationsandDataAnalysis . 100 4.2.1 Target selection . 100 4.2.2 Spectroscopy ........................... 100 4.2.3 New radial velocities . 101 4.2.4 Radial velocities from the literature . 108 4.3 NewandUpdatedBinaryOrbits . 111 4.3.1 HD92607 ............................. 114 4.3.2 HD93576 ............................. 117 4.3.3 HDE303312............................ 119 4.3.4 HDE305536............................ 122 4.3.5 Additional spectroscopic binaries . 122 4.4 Results and Discussion . 125 4.4.1 Distribution of stellar radial velocities . 125 4.4.2 Variations between clusters . 128 4.4.3 Comparison to molecular gas . 131 4.4.4 Comparison to ionized gas . 141 4.5 Conclusions ................................ 142 CHAPTER 5 SUMMARY AND FUTURE PROSPECTS . 145 REFERENCES................................... 149 8 LIST OF FIGURES 2.1 HST WFPC2 F658N image of η Caranditsouterejecta . 37 2.2 ACS 2005–2014 and WFPC2 1993–2001 difference images . 40 2.3 Boxes used to measure proper motions of the E condensations . ... 43 2.4 Histogramsofejectapropermotions. 47 2.5 Proper motion versus time for three representative features ...... 49 2.6 Comparison to Thackeray (1950)images ................ 51 2.7 Proper motion vectors color-coded by apparent ejection date ..... 53 2.8 Transverse velocity versus projected distance from η Car . 54 2.9 Histogramsofapparentejectiondates. 56 2.10 EjectaoutsidetheprimaryACSfootprint. 58 2.11 Proper motion vectors overlaid on soft X-ray emission . .. 60 3.1 HST ACS fields across the Carina Nebula . 74 3.2 Differenceimagesandbest-fitpixeloffsets . 77 3.3 Spitzer IRAC images showing bow shock orientations . 83 3.4 Comparisontoabsolutepropermotions. 88 3.5 Comparison to Gaia DR1 corrected to a local reference frame . 90 4.1 O-type and evolved massive stars in the Carina Nebula . 97 4.2 Representative CHIRON spectra of four O-type stars . ... 102 4.3 HD 92607 He I λ5876inphaseorder .................. 115 4.4 HD92607RVcurveandorbitalsolution . 116 4.5 HD93576RVcurveandorbitalsolution . 118 4.6 HDE303312RVcurveandorbitalsolutions
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