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Downloaded on 2017-09-05T00:30:50Z Physics in the Extreme: X-Ray and Optical Studies of Magnetic White Dwarfs and Related Objects Title Physics in the extreme: X-ray and optical studies of magnetic white dwarfs and related objects Author(s) Kennedy, Mark Publication date 2017 Original citation Kennedy, M. 2017. Physics in the extreme: X-ray and optical studies of magnetic white dwarfs and related objects. PhD Thesis, University College Cork. Type of publication Doctoral thesis Rights © 2017, Mark Kennedy. http://creativecommons.org/licenses/by-nc-nd/3.0/ Embargo information No embargo required Item downloaded http://hdl.handle.net/10468/4038 from Downloaded on 2017-09-05T00:30:50Z Physics in the extreme: X-ray and optical studies of magnetic white dwarfs and related objects Mark Kennedy BSC 109482792 ¡ NATIONAL UNIVERSITY OF IRELAND, CORK SCHOOL OF SCIENCE DEPARTMENT OF PHYSICS Thesis submitted in partial fulfilment of the requirement for the degree of Doctor of Philosophy March 2017 Head of Department: Prof. John McInerney Supervisors: Prof. Paul Callanan Prof. Peter Garnavich External Examiner: Dr. Chris Watson Queen’s University Belfast Internal Examiner: Dr. Asaf Pe’er University College Cork Research supported by The Naughton Foundation Contents Contents List of Figures...............................v List of Tables............................... viii Abstract..................................x Acknowledgements............................ xii 1 Introduction1 1.1 Observational Properties of Binary Systems...........3 1.1.1 Non-magnetic CVs.....................3 1.1.1.1 Dwarf Novae...................3 1.1.1.2 Nova-likes....................6 1.1.1.3 SW Sextantis Systems..............6 1.1.2 Magnetic CVs........................7 1.1.2.1 Polar (AM Her) Stars..............7 1.1.2.2 DQ Her Stars...................8 1.1.3 Low Mass X-ray Binaries..................8 1.2 Roche lobe geometry of accreting systems............9 1.2.1 X-ray Luminosity-Accretion Rate relation......... 12 1.2.2 The Accretion Disc..................... 13 1.3 Formation of Cataclysmic Variables................ 17 1.3.1 P distribution of CVs.................... 20 1.3.1.1 The Period Gap.................. 22 1.3.1.2 The Period Minimum.............. 22 1.4 Classification of CVs revisited................... 24 1.4.1 Nova Outbursts....................... 24 1.4.1.1 Recurrent Nova................. 25 1.4.1.2 Low Mass X-ray Binaries............. 25 1.4.2 Non-magnetic CVs..................... 26 1.4.2.1 Dwarf Novae................... 26 1.4.2.2 SU UMa...................... 27 1.4.2.3 Z Cam....................... 28 1.4.2.4 Nova-likes.................... 29 1.4.2.5 SW Sextantis Systems.............. 29 1.4.3 Polar (AM Her) Stars.................... 30 1.4.4 DQ Her Stars........................ 30 1.5 Structure of Thesis......................... 33 2 Data Reduction 35 2.1 FITS Files.............................. 36 2.2 Optical Photometry......................... 36 2.2.1 Bias Correction....................... 37 2.2.2 Flat field Correction.................... 38 2.3 Optical Spectroscopy........................ 38 2.3.1 Spectral Extraction..................... 39 2.3.2 Wavelength Calibration.................. 40 i Contents 2.3.3 Flux Calibration...................... 41 2.4 HST COS.............................. 41 2.5 Kepler Data............................. 42 2.6 X-ray Data.............................. 44 2.6.1 Event Patterns/Grades................... 45 2.6.2 Soft Proton Flaring..................... 46 2.6.3 Extraction.......................... 47 2.6.4 Pile-up............................ 48 3 The new eclipsing CV MASTER OTJ192328.22+612413.5 - a possi- ble SW Sextantis Star 49 3.1 Introduction............................. 50 3.2 Observations............................ 51 3.2.1 Photometry......................... 51 3.2.2 Spectroscopy........................ 51 3.3 Results................................ 53 3.3.1 Period and Ephemeris................... 53 3.3.2 Light curve Morphology.................. 56 3.3.3 Emission Spectrum..................... 58 3.4 Discussion.............................. 59 3.4.1 Inclination and Mass Ratio of J1923........... 59 3.4.1.1 Modelling the quiescent light curve...... 60 3.4.2 Modelling the spectrum.................. 61 3.4.3 Similarity to Lanning 386................. 64 3.5 Conclusions............................. 66 4 XMM-Newton Observations of the Peculiar CV Lanning 386: X-ray Evidence for a Magnetic Primary 68 4.1 Introduction............................. 69 4.2 Observations............................ 69 4.2.1 J1923............................ 71 4.3 Timing Analysis........................... 71 4.3.1 Optical Light Curve..................... 71 4.3.2 X-ray Light Curves..................... 74 4.3.3 Power Spectrum...................... 75 4.4 Spectral Analysis.......................... 77 4.4.1 Optical........................... 77 4.4.2 X-ray............................. 81 4.4.2.1 Equivalent Widths and intensities of the Fe lines 83 4.4.3 An updated distance measurement............ 84 4.5 Discussion.............................. 85 4.5.1 Is Lanning 386 magnetic?................. 85 4.5.1.1 Fe line comparisons............... 88 4.5.1.2 An upper limit of the magnetic moment of Lan- ning 386..................... 89 4.5.2 The X-ray flux limit for J1923............... 89 4.6 Conclusion............................. 90 ii Contents 5 Kepler K2 Observations of the Intermediate Polar FO Aquarii 93 5.1 Introduction............................. 94 5.2 Observations............................ 95 5.3 Light Curve Analysis........................ 96 5.3.1 Full Light Curve...................... 96 5.3.2 Phased light curve..................... 98 5.4 Variability of the Spin Signal.................... 99 5.4.1 Variability of Spin Period.................. 100 5.4.2 Variability of Spin Phase.................. 102 5.4.3 Modulation of the Spin and Beat Frequencies...... 105 5.5 Conclusion............................. 106 6 X-ray observations of FO Aquraii during and after the 2016 low state 108 6.1 Introduction............................. 109 6.2 Observations............................ 111 6.2.1 Swift ............................. 111 6.2.2 Chandra ........................... 112 6.2.3 XMM Newton........................ 112 6.2.3.1 Ground-based Photometry........... 113 6.3 Analysis............................... 113 6.3.1 Timing Analysis....................... 113 6.3.1.1 The Spin Period of FO Aqr............ 113 6.3.1.2 X-ray....................... 115 6.3.2 Spectral Analysis...................... 116 6.3.2.1 Low State..................... 116 6.3.2.2 Recovery State.................. 121 6.4 Discussion.............................. 122 6.4.1 Long Term Recovery.................... 122 6.4.2 The softened X-ray spectrum............... 123 6.4.3 The Recovery State..................... 125 6.4.4 X-ray and Optical Pulse.................. 128 6.4.4.1 Low State..................... 128 6.4.4.2 Recovery State.................. 129 6.5 Conclusions............................. 133 7 The Evolved Main-Sequence Channel: HST and LBT observations of CSS120422:111127+571239 135 7.1 Introduction............................. 136 7.2 Observations and Analysis..................... 139 7.2.1 HST Observations..................... 139 7.2.2 LBT Observations...................... 141 7.2.3 VATT Observations..................... 141 7.2.4 APO Observations..................... 142 7.3 Results................................ 142 7.3.1 Optical Spectrum...................... 142 7.3.2 UV Spectrum........................ 149 iii Contents 7.3.2.1 Average Spectrum................ 149 7.3.2.2 TIME-TAG Light Curves............. 150 7.4 White Dwarf Temperature..................... 152 7.5 An evolving disc.......................... 155 7.6 The Evolved Main Sequence Channel............... 158 7.6.1 V418 Ser.......................... 160 7.6.2 EMS Channel and Type Ia Supernovae.......... 161 7.7 Conclusions............................. 164 8 Do X-ray bursts dream of optical reprocessing? - The optical bursts in UW CrB 166 8.1 Introduction............................. 167 8.2 Observations............................ 168 8.2.1 Photometry......................... 168 8.2.2 Spectroscopy........................ 168 8.3 Orbital Ephemeris......................... 170 8.4 Optical Spectrum.......................... 171 8.4.1 Optical Burst Spectrum.................. 175 8.5 Optical Bursts............................ 176 8.5.1 Modeling Optical bursts.................. 176 8.5.2 Orbital phases of the bursts................ 179 8.6 Conclusions............................. 179 9 Summary & Future Work 182 9.1 Lanning 386 & J1923........................ 183 9.1.1 Future Work........................ 183 9.2 FO Aqr................................ 184 9.2.1 Future Work........................ 185 9.3 CSS1111.............................. 185 9.3.1 Future Work........................ 186 9.4 UW CrB............................... 186 9.4.1 Future Work........................ 186 A List of Publications 188 A.1 Peer-reviewed Publications..................... 188 A.2 Oral Presentations......................... 189 A.3 Conference Poster Presentations.................. 189 iv List of Figures List of Figures 1.1 Schematic of a CV.........................4 1.2 Light curve of HS Vir........................5 1.3 An optical spectrum from a CV..................5 1.4 Example light curve from a CV..................6 1.5 The optical pulses seen from an Intermediate Polar.......8 1.6 Roche lobe geometry for a binary system............. 11 1.7 Ballistic stream in a binary..................... 14 1.8 Evolution of an accretion disc..................
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