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UNIVERSITY OF CALIFORNIA, SAN DIEGO Exploring the Geometry of Circumnuclear Material in Active Galactic Nuclei through X-ray Spectroscopy A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Physics by Elizabeth Rivers Committee in charge: George Fuller, Chair Richard Rothschild, Co-Chair Kim Griest Stefan Llewellyn Smith Kevin Quest 2012 Copyright Elizabeth Rivers, 2012 All rights reserved. The dissertation of Elizabeth Rivers is approved, and it is acceptable in quality and form for publication on mi- crofilm and electronically: Co-Chair Chair University of California, San Diego 2012 iii TABLE OF CONTENTS SignaturePage .................................. iii TableofContents................................. iv ListofFigures .................................. vii ListofTables................................... ix Acknowledgements ................................ x Vita and Publications . xii AbstractoftheDissertation . xiii 1 Introduction.................................. 1 1.1 AnatomyofanAGN .......................... 2 1.1.1 TheAccretionDisk....................... 3 1.1.2 The Broad and Narrow Emission Line Regions . 5 1.1.3 TheDustyTorus ........................ 6 1.1.4 Relativistic Jets . 7 1.2 X-raySpectralPropertiesofAGN. 9 1.2.1 Absorption ........................... 10 1.2.2 TheComptonReflectionHump . 11 1.2.3 The Fe K emission complex . 14 1.2.4 TheSoftExcess......................... 15 1.2.5 Previous Surveys and the Advantages of Broad X-ray Spec- tralAnalysis........................... 16 2 RXTE, Suzaku andDataReduction .................... 18 2.1 The Rossi X-ray Timing Explorer ................... 18 2.1.1 TheProportionalCounterArray . 20 2.1.2 The High Energy X-ray Timing Experiment . 23 2.1.3 HEXTE Background Considerations . 25 2.2 Suzaku.................................. 27 2.2.1 TheX-rayImagingSpectrometer . 27 2.2.2 TheHardX-rayDetector . 29 2.3 Methodology .............................. 30 2.4 Acknowledgements ........................... 30 iv 3 The RXTE ActiveGalacticNucleiSurvey . 31 3.1 The 23 Brightest AGN in the RXTE Archive............. 31 3.1.1 Selection Criteria . 32 3.1.2 The20–100keVBandpass . 33 3.1.3 Model Fitting of the 23 AGN Broad Sample . 33 3.2 FullSpectralSurvey .......................... 40 3.2.1 Selection Criteria . 40 3.2.2 MethodsandAnalysis ..................... 41 3.3 ResultsfortheSeyfertSample . 44 3.3.1 ComparisonstoPreviousSurveys . 48 3.3.2 The Circumnuclear Material . 51 3.3.3 High Energy Rollovers . 55 3.4 ResultsfortheBlazarSample . 57 3.5 TablesforChapter3 .......................... 59 3.6 Acknowledgements ........................... 72 4 AnEclipseofCentaurusA.......................... 73 4.1 TimeResolvedSpectralAnalysis . 76 4.2 ImplicationsforaClumpyTorus. 79 4.3 Acknowledgements ........................... 83 5 TheGeometryofMCG–2-58-22. 84 5.1 DetailsoftheObservation . 85 5.2 SpectralFitting............................. 87 5.2.1 TheFeKBandpass....................... 87 5.2.2 BroadbandFitting ....................... 90 5.2.3 Applying a Self-Consistent Model . 94 5.3 Results.................................. 96 5.3.1 TheFeKComplex ....................... 96 5.3.2 Reflection and Geometry of the Circumnuclear Material . 97 5.3.3 Optical ObscurationandX-rayAbsorption . 98 5.4 Acknowledgements ........................... 99 6 TheDisappearingSoftExcessinMkn590 . 100 6.1 SpectralAnalysis ............................102 6.1.1 Simultaneous Fitting of Suzaku and XMM-Newton Data . 104 6.1.2 Fe K Complex Analysis . 108 6.2 Results..................................108 6.2.1 TheSoftX-rayConundrum . 109 6.3 Acknowledgements ........................... 112 v 7 SummaryofResults .............................113 7.1 IndividualObjects ........................... 113 7.1.1 TheClumpyAbsorberinCenA. 113 7.1.2 The Circumnuclear Material in MCG–2-58-22 . 114 7.1.3 TheDisappearingSoftExcessinMkn590 . 115 7.2 TheArchivalSurveys. 115 7.3 Conclusion................................117 7.4 Acknowledgements ........................... 119 vi LIST OF FIGURES Figure1.1: MeanSEDsforquasars . 3 Figure 1.2: Characteristic double-humped blazar SEDs . 4 Figure 1.3: Unified AGN model from Urry & Padovani (1995) . 6 Figure 1.4: Clumpy torus model from Nenkova et al. (2008b) . .. 8 Figure 1.5: X-ray spectral components for Seyferts . ..... 10 Figure 1.6: Compton reflection hump and fluorescent lines from Compton reflectionoffacoldslab ...................... 12 Figure1.7: TheFeKemissioncomplex . 15 Figure 2.1: Sample lightcurves of several bright AGN from the RXTE archive 19 Figure 2.2: The RXTE spacecraft ....................... 21 Figure 2.3: The PCA individual units and assembly . 22 Figure2.4: DiagramofaphoswichusedinHEXTE . 24 Figure 2.5: HEXTE clusters A and B rocking patterns and field of view . 26 Figure2.6: AsingleXISCCDcamera. 28 Figure 2.7: The Suzaku HXDandGSO .................... 29 Figure 3.1: Data, model and data–model residuals for four Seyfert 1’s in thebroadsample.......................... 35 Figure 3.2: Data, model and data–model residuals for four Seyfert 2’s in thebroadsample.......................... 36 Figure 3.3: Data, model and data–model residuals for the four blazars in thebroadsample.......................... 37 Figure 3.4: Data to model ratios for NGC 4945 and Circinus illustrating reflectionvsrollovermodels . 38 Figure 3.5: Contour plots of various parameters for Seyfert 2’s . ..... 39 Figure 3.6: Γ distribution by Seyfert type. 46 Figure 3.7: R and F R distributionsbySeyferttype . 46 Figure 3.8: Stacked X-ray νFν spectraforSeyferts . 49 Figure 3.9: L2−10 vsΓforSeyferts....................... 50 Figure 3.10: LBol/LEdd vsΓforSeyferts .................... 50 Figure 3.11: R vs Fe line equivalent width for Seyfert 1’s and 2’s . 54 Figure 3.12: Γ distribution by blazar type . 56 Figure 3.13: Luminosity versus photon index for the blazars in our sample . 57 Figure 4.1: Light curves for the Cen A monitoring campaign . 75 Figure4.2: Timeresolvedspectralparameters . 76 Figure 4.3: Two sample spectra with data and best-fit residuals . .. 77 Figure 4.4: Model fits to the NH occultationprofile . 80 Figure 4.5: The linear-density sphere applied to the 2003–2004 increase in NH .................................. 82 vii Figure 5.1: Lightcurve over the duration of the Suzaku observation of MCG – 2-58-22 ............................... 86 Figure 5.2: Data–model residuals for a simple power law fit over the Fe K band................................. 88 Figure 5.3: Spectral fitting for MCG–2-58-22 from 0.7–50 keV . ... 91 Figure 5.4: Historical values for the 2–10 keV flux . 94 Figure 6.1: 2–10 XIS lightcurve for the Suzaku observation of Mkn 590 . 101 Figure6.2: XISandPINdataandfitresiduals . 103 Figure 6.3: Suzaku and XMM-Newton data and fit residuals for simultane- ousfitting..............................106 viii LIST OF TABLES Table3.1: AveragesbySourceType . 44 Table3.2: FullSurveySourceList . 59 Table3.2: FullSurveySourceList . 60 Table3.2: FullSurveySourceList . 61 Table3.2: FullSurveySourceList . 62 Table3.3: The20–100keVband. 63 Table 3.4: Broad Sample Fitting Results . 64 Table3.5: RolloverModels ........................... 65 Table3.6: Seyfert1’s: BaseModelFitParameters . 66 Table3.7: Seyfert2’s: BaseModelFitParameters . 67 Table 3.8: Complex Models for Seyferts: Partial Covering and Scattered Emission............................... 68 Table 3.9: Blazars: Power-Law Model Parameters . 69 Table 3.10: Blazars: Broken Power-Law Model Parameters . .... 70 Table 3.11: Other AGN in the RXTE Archive ................ 70 Table 3.11: Other AGN in the RXTE Archive ................ 71 Table 3.11: Other AGN in the RXTE Archive ................ 72 Table5.1: ModelParameters. 93 Table 5.2: Model Parameters for MYTorus ................. 95 Table6.1: ParametersforBest-fitModels . 105 ix ACKNOWLEDGEMENTS I would like to thank the following people: Alex Markowitz for all his men- torship and hard work; J¨orn Wilms and Katja Pottschmidt for invaluable advice; My office mates Slawo Suchy and Paul Hemphill for being my computer gurus and for being someone to laugh with; Mark Rafelski and Jonathon Whitmore for lead- ing the way; Alex Diamond-Stanic and Alison Coil for being excellent role models; Mike Gollner, Agnieszka Cieplak, and Kevin and Tali Ball for moral support and the occasional (okay frequent) rides to the airport; Mom, Dad, Malia, and the rest of my family for setting me on this path and encouraging me the whole way; Chuck for the flowers and the pancakes and for making the whole thing bearable; And last, but not least, thank you Rick, for being the most understanding and patient advisor I could have asked for. Chapter 2, in part, is a reproduction of material as it appears in the As- trophysical Journal, Rivers, Markowitz & Rothschild, ApJ, 2011a, and Rivers, Markowitz, Duro & Rothschild, ApJ, 2012; and in part has been submitted for publication to the Astrophysical Journal 2012, Rivers, Markowitz & Rothschild. The dissertation author was the primary investigator and author of this material. Chapter 3, in part, is a reproduction of material as it appears in the Astro- physical Journal 2011, Rivers, Markowitz & Rothschild, ApJ, 2011a; and, in part, has been submitted for publication to the Astrophysical Journal 2012, Rivers, Markowitz & Rothschild. The dissertation author was the primary investigator and author of this material. Chapter 4, in full, is a reproduction of material as it appears in the Astro- physical Journal 2011, Rivers, Markowitz & Rothschild, ApJ, 2011c.