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Harvesting Planets in the Inner and Outer Galaxy A HARVESTING PLANETS IN THE INNER AND OUTER GALAXY A THESIS SUBMITTED TO THE GRADUATE SCHOOL IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE MASTER OF SCIENCE BY JOSEPH D. KINDT DR. GUILLERMO GONZALEZ – ADVISOR BALL STATE UNIVERSITY MUNCIE, INDIANA DECEMBER 2015 For Allison, Lucy, Oliver, and the New Baby. TABLE OF CONTENTS ABSTRACT ................................................................................................................................. iv ACKNOWLEDGEMENTS ....................................................................................................... vi LIST OF FIGURES ................................................................................................................... vii LIST OF TABLES ....................................................................................................................... x 1. INTRODUCTION .............................................................................................................. 1 1.1 Background ................................................................................................................ 1 1.2 Radial Metallicity Gradient ...................................................................................... 2 1.3 Stellar Metallicity/Planet Incidence ......................................................................... 3 1.4 “Hot Jupiters” ............................................................................................................ 4 1.5 M-dwarfs ..................................................................................................................... 6 1.6 Interstellar Extinction ............................................................................................... 6 1.7 Transit Detection Method ......................................................................................... 6 1.8 Galactic Plane Studies ............................................................................................... 7 1.9 Difference Imaging ..................................................................................................... 8 1.10 Experimental Setup ................................................................................................... 9 2. SIMULATION .................................................................................................................. 11 2.1 Theory ....................................................................................................................... 11 2.2 Method ...................................................................................................................... 13 2.3 Analysis ..................................................................................................................... 16 3. IMAGE REDUCTION ..................................................................................................... 20 i 3.1 Software Environment and Requirements ............................................................... 20 3.2 IRAF Setup and Usage ............................................................................................... 21 3.3 Bias Correction ............................................................................................................ 24 3.4 Flat Field Correction .................................................................................................. 31 3.5 Fringe Correction ........................................................................................................ 35 4. pyDIA .................................................................................................................................. 43 4.1 Background .............................................................................................................. 43 4.2 Software Requirements ........................................................................................... 43 4.3 Hardware .................................................................................................................. 44 4.4 Input .......................................................................................................................... 45 4.5 Usage ......................................................................................................................... 47 4.6 Output ....................................................................................................................... 49 4.7 Unit Conversion ....................................................................................................... 50 5. VARTOOLS ........................................................................................................................ 52 5.1 Installation ................................................................................................................ 52 5.2 Basic Usage ............................................................................................................... 52 5.3 Programs ................................................................................................................... 53 6. VaST ................................................................................................................................... 61 6.1 Introduction .............................................................................................................. 61 6.2 Software Requirements/Installation ....................................................................... 61 6.3 Input .......................................................................................................................... 62 6.4 Output and Utilities ................................................................................................. 63 6.5 Magnitude Calibration ............................................................................................ 65 ii 6.6 Results ....................................................................................................................... 66 7. Observations ...................................................................................................................... 71 8. Results ................................................................................................................................ 72 8.1 Introduction .............................................................................................................. 72 8.2 pyDIA/VARTOOLS ................................................................................................... 72 8.3 VaST .......................................................................................................................... 78 8.3.1 PSF Photometry Method ................................................................................... 78 8.3.2 Aperture Photometry Method .......................................................................... 84 8.4 Result Coordinates ................................................................................................... 90 8.5 Variable Candidate Classification .......................................................................... 95 8.6 Significance of Results ............................................................................................. 95 9. Conclusion ......................................................................................................................... 98 References ................................................................................................................................... 99 Appendix A: IRAF flatcombine Parameters ......................................................................... 105 Appendix B: Fix JD FITS Values ........................................................................................... 106 Appendix C: Sample pyDIA Script ......................................................................................... 107 Appendix D: Sample VARTOOLS Command ....................................................................... 108 Appendix E: Installation of PSFEx for VaST ....................................................................... 109 iii ABSTRACT THESIS: Harvesting Planets in the Inner and Outer Galaxy STUDENT: Joseph D. Kindt DEGREE: Master of Science COLLEGE: Science and Humanities DATE: December 2015 PAGES: 126 This thesis project involves the creation of a data analysis pipeline that will be used for the study of the incidence of exoplanets in the midplane of the Galaxy. The procedure for the reduction of data is designed to use IRAF, and the procedure for the analysis of the data uses pyDIA and VaST. pyDIA is a program that performs difference imaging and photometry and is designed for use with crowded fields; VaST includes aperture and psf-fitting photometry methods. Sample data of the fields of interest are used in the design of the analysis procedure. These images were obtained using the SARA-S Observatory telescope. The results from VaST and pyDIA are compared in order to select the most appropriate analysis method. Seven variable star candidates in the data set were discovered using both programs. Light curves and coordinates of these stars are presented. Specifically, the analysis pipeline will be used in future research to investigate the incidence of exoplanets at different galactocentric distances. The incidence of exoplanets should decrease with increasing distance from the galactic center. This prediction is based upon two known relationships. The first is the relationship between the incidence of giant
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