WTS-1 B: the first Extrasolar Planet Detected in the WFCAM Transit Survey
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WTS-1 b: the first extrasolar planet detected in the WFCAM Transit Survey Michele Cappetta M¨unchen2012 WTS-1 b: the first extrasolar planet detected in the WFCAM Transit Survey Michele Cappetta Dissertation an der Fakult¨atf¨urPhysik der Ludwig{Maximilians{Universit¨at M¨unchen vorgelegt von Michele Cappetta aus Bolzano, Italien M¨unchen, den 19. Dezember 2012 Erstgutachter: R. P. Saglia Zweitgutachter: B. Ercolano Tag der m¨undlichen Pr¨ufung:5. Februar 2013 Contents Zusammenfassung xix Summary xxi 1 Extrasolar planets 1 1.1 Introduction . .2 1.2 Detection methods . .4 1.3 Planet formation . .7 1.3.1 The Solar Nebular Model . .7 1.3.2 Rocky planets formation . .8 1.3.3 Gas-giant planets formation . 10 1.4 Planet evolution . 13 1.4.1 Gas disk migration . 13 1.4.2 Planetesimal-driven migration . 14 1.4.3 Planet-planet scattering . 16 1.5 Extrasolar planets properties . 17 1.5.1 Radius anomaly of the hot-Jupiters . 22 2 WFCAM Transit Survey 25 2.1 Observing strategy . 27 2.2 Reduction pipeline . 29 2.3 Transit detection algorithm . 32 2.4 Transit recovery ratios . 34 2.5 Results . 37 3 Instrumentation and spectroscopic observations 39 3.1 Hobby-Eberly Telescope . 40 3.2 The HRS Spectrograph . 42 3.3 Instrumental configurations . 46 3.4 Visit types . 49 4 Reduction and analysis pipeline 51 4.1 Introduction . 52 vi CONTENTS 4.2 Data reduction . 54 4.2.1 Cosmic-rays filtering . 54 4.2.2 Frames calibration . 54 4.2.3 Apertures definition . 55 4.2.4 Spectra extraction . 58 4.2.5 Wavelength calibration . 61 4.3 Data analysis . 66 4.3.1 Crop of the spectra . 66 4.3.2 Spectra normalization . 68 4.3.3 Telluric lines removal . 72 4.3.4 Cosmic-rays peaks removal . 74 4.3.5 Spectra resampling . 76 4.3.6 Cross-correlation . 77 4.3.7 Final RV values . 78 5 Observations and results 85 5.1 Pipeline characterization . 87 5.1.1 HD 195019 . 87 5.1.2 HD 352939 . 88 5.1.3 GJ 1214 . 90 5.1.4 M 67 . 91 5.2 WTS1 b . 95 5.2.1 Observations . 95 5.2.2 Spectroscopic data . 97 5.2.3 Stellar parameters . 99 5.2.4 Planetary parameters . 106 5.2.5 Discussion . 112 5.3 WTS2 b . 115 5.3.1 Stellar parameters . 116 5.3.2 Planetary parameters . 117 5.3.3 Discussion . 120 5.4 NLTT 5306 . 123 5.4.1 Observations . 124 5.4.2 Analysis . 125 5.4.3 Discussion . 131 6 Conclusions 135 A Keplerian orbit model 141 B Analytic light curve transit 143 B.1 Uniform source . 143 B.2 Limb-darkening . 146 Table of contents vii B.3 Small planets . 148 viii Table of contents List of Figures 1.1 Statue of Giordano Bruno . .1 1.2 Detection methods: radial velocity and transit . .4 1.3 Detection methods: gravitational microlensing and astrometry . .5 1.4 T-Tauri star . .7 1.5 Snow line . .8 1.6 Habitable zone . .9 1.7 Disk instability model . 10 1.8 Core accretion model . 11 1.9 Proto-planetary gas surface density . 13 1.10 Trans-Neptunian objects . 15 1.11 Frequency histograms of mass, radius, period and eccentricity . 18 1.12 Planetary mass and period probability density functions . 19 1.13 Correlation plots of the properties of the known extrasolar planets . 20 1.14 Radius versus mass for giant planets . 22 2.1 The United Kingdom Infrared Telescope . 25 2.2 WTS fields . 26 2.3 WTS pawprints . 27 2.4 WTS sensitivity . 28 2.5 WTS RMS . 31 2.6 Example of a transit in a J-band LC . 33 2.7 Recovery ratios of simulated transiting system for M0 scenarios . 35 2.8 Recovery ratios of simulated transiting system for M2 scenarios . 36 2.9 Short period HJ planetary occurrence fractions . 37 3.1 The Hobby-Eberly telescope . 39 3.2 Example of an HRS scientific exposure . 42 3.3 HRS optical scheme . 43 3.4 Example of the HRS calibration frames . 44 3.5 Raw science frame measured with sky fibers . 47 4.1 Roman aqueducts . 51 4.2 Aperture definition, red component . 56 x LIST OF FIGURES 4.3 Aperture tracing, dark column example . 57 4.4 Extracted spectrum related to a single echelle order . 59 4.5 Sky spectrum subtraction . 60 4.6 Template plot from the ThAr atlas . 62 4.7 Wavelength calibrated spectrum . 64 4.8 CROP SPECTRA: user selection . 66 4.9 Spectra normalization with CONT AUTO .................... 69 4.10 Spectra normalization with CONT USER .................... 71 4.11 Example of the telluric lines in the observed spectra . 72 4.12 TELL REMOV: telluric-free spectra . 73 4.13 CRs filtered spectra with COSMIC REMOV ................... 75 4.14 Correlation function computed with rv.fxcor ................ 78 4.15 All the 64 raw RV values related to each single order . 80 4.16 Raw RV values related to all the orders and to all the epochs . 81 4.17 Uncorrected RVs . 82 4.18 Final heliocentric RVs . 83 5.1 Angel with the Sudarium . 85 5.2 HD195019 .................................... 87 5.3 HD352939 .................................... 89 5.4 GJ1214 b ..................................... 90 5.5 Offsets between the HARPS and HET . 92 5.6 RV of a star in M 67 measured with HARPS and HET . 93 5.7 The unfolded J-band LC for WTS1 ....................... 96 5.8 SED analysis of WTS1 .............................. 99 5.9 Intermediate resolution spectrum of WTS1 ................... 101 5.10 Intermediate resolution ISIS spectrum . 102 5.11 High-resolution Li i line at ∼6707 A......................˚ 103 5.12 WFCAM J-band light curve data of WTS1 .................. 107 5.13 INT i0-band light curve data of WTS1 ..................... 108 5.14 RV values and best-fit of WTS1 ......................... 110 5.15 Mass { Radius diagram of the known planets with a mass in the range 3-5 MJ 113 5.16 SED analysis of WTS2 .............................. 117 5.17 J and i-band LC for WTS2 ........................... 118 5.18 RVs values and best-fit of WTS2 ........................ 119 5.19 Planetary radius as a function of planetary mass . 121 5.20 Predicted Ks-band secondary eclipse depths . 122 5.21 Phase folded INT i'-band LC of NLTT 5306 ................. 126 5.23 Phase.