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What do we know about the exo-planets? & How to detect direct signals from exo-planets?. Florian Rodler. Introduction 201 confirmed planetary candidates + 14 confirmed planets found around solar-like stars and pulsars (in 175 planetary systems). -12. Introduction
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What do we know about the exo-planets? &How to detect direct signals from exo-planets? Florian Rodler what do we know from the exo-planets?
Introduction • 201 confirmed planetary candidates + 14 confirmed planets found around solar-like stars and pulsars (in 175 planetary systems) -12 what do we know from the exo-planets?
Introduction • 201 confirmed planetary candidates + 14 confirmed planets found around solar-like stars and pulsars (in 175 planetary systems) • transit + RV: i ≈ 90°.Exact mass determinationpossible: MPlanet_min = MPlanet . • RV: only minimum mass: MPlanet_min = MPlanetsini • microlensing: estimation of planetary mass • → companion a browndwarf (M>13 Mjup) ? -12 what do we know from the exo-planets?
Introduction • 201 confirmed planetary candidates + 14 confirmed planets found around solar-like stars and pulsars (in 175 planetary systems) exact determination of mass needed!!! • transit + RV: i ≈ 90°.Exact mass determinationpossible: MPlanet_min = MPlanet . • astrometry (→ future) • transit + RV • direct imaging- reflected light (+RV) -12 what do we know from the exo-planets?
Introduction (2) Some do we know about these planets? - Planetary masses (mostly Mplanet_min): 6 MEarth – 13 MJupiter (most planets > 0.5 MJupiter)- very close to host star: 0.03 – 60 AU (most planets < 0.1 AU: hot Jupiters) Hot Jupiter Mercury -11 0.5 AU what do we know from the exo-planets?
Introduction (2) Some parameters of the planets found: - Planetary masses (mostly Mplanet_min): 6 MEarth – 13 MJupiter (most planets > 0.5 MJupiter)- very close to host star (0.03 – 6 AU) -11 what do we know from the exo-planets?
Introduction (2) Some do we know about those planets? - Planetary masses (mostly Mplanet_min): 6 MEarth – 13 MJupiter (most planets > 0.5 MJupiter)- very close to host star: 0.03 – 60 AU (most planets < 0.1 AU: hot Jupiters)- planets are heated up: radii are large (transits!) -11 what do we know from the exo-planets?
Introduction (2) Some do we know about those planets? - Planetary masses (mostly Mplanet_min): 6 MEarth – 13 MJupiter (most planets > 0.5 MJupiter)- very close to host star:0.03 – 60 AU (most planets < 0.1 AU: hot Jupiters)- planets are heated up: radii are large (transits!)- planetary atmospheres (transits, direct imaging, reflected light) -11 what do we know from the exo-planets?
Introduction (2) Some do we know about those planets? - Planetary masses (mostly Mplanet_min): 6 MEarth – 13 MJupiter (most planets > 0.5 MJupiter)- very close to host star: 0.03 – 60 AU (most planets < 0.1 AU: hot Jupiters)- planets are heated up: radii are large (transits!)- planetary atmospheres (transits, direct imaging, reflected light) "Direct methods" -11 what do we know from the exo-planets?
"Direct methods“ ... detecting a direct signal from the planet (a) transits (b) direct imaging (c) reflected light (d) other stuff ... -10 what do we know from the exo-planets?
Transits -9 Atmosphere of the planet around HD 209458 (Charbonneau … 2001) what do we know from the exo-planets?
Transits TrES-1: thermal signature of atmosphere found (Charbonneau ... 2005) -8 what do we know from the exo-planets?
Direct imaging Planet 2M1207 (Chauvin ... 2005) Star-planet flux ratio decreased - for young objects (self-lum.) - in the NIR Close-in planets can hardly be imaged (< 0.1“)! -7 what do we know from the exo-planets?
Direct imaging Planet 2M1207 (Chauvin ... 2005) Star-planet flux ratio decreased - for young objects (self-lum.) - in the NIR Close-in planets can hardly be imaged (< 0.1“)! Flux wavelength (micron) Flux wavelength (micron) -7 Burrows ... 2003) what do we know from the exo-planets?
Reflected Light :: Motivation Jupiter – Sun flux ratio in the visual : 1/250 000 000(seen from outer space) -6 what do we know from the exo-planets?
Reflected Light :: Motivation Jupiter – Sun flux ratio in the visual : 1/250 000 000(seen from outer space) Hot Jupiters are 100x closer: 0.05 AU → planet-star flux ratio ≈ 1/25 000 for a Jupiter sized planet!? hot Jupiters E J 0.05 0.5 5 [AU] log distance from host star -6 what do we know from the exo-planets?
Reflected light High resolution, high S/N spectroscopy of star + planet in the visual! → approx. 2300 stellar absorption lines + → these lines reflected by the planet, BUT- Doppler shifted due to orbital motion- faint (a few times 1/10000 ) → looking for the same pattern in the spectra: each stellar spectral line has its reflected counterpart ... -5 what do we know from the exo-planets?
schematics ... -4 what do we know from the exo-planets?
Requirements bright host stars(spectroscopy!) hot Jupiters (periods of 3-5 days) and lots of data (S/N)! Reflected light Hot Jupiter Mercury 0.5 AU -3 what do we know from the exo-planets?
What will we learn ... ... once we detect reflected light? orbital inclination (+RV) → exact planetary mass information about planetary atmosphere → input for theory! Reflected light -2 what do we know from the exo-planets?
Reflected light Find planetary signature: chi2 minimisation → calculate fits for K and contrast → best fit for planet → significance of detection: MC -1 what do we know from the exo-planets?
Conclusions on direct methods • transits atmospheres (VIS, IR), young and old radii moons!? i ≈ 90° (b) direct imagingatmospheres (IR), young objects only not close to star (c) reflected light atmospheres (VIS), old objects onlyvery close to star bright objects 0 what do we know from the exo-planets?
some stuff about Florian Rodler ... Studies at Vienna observatory (1997 - ???), Austria PhD student at MPIA, supervised by Martin Kürster Topics of interest: beer & dancing atmospheres of exo planets, direct detections pulsating stars observing Hobbies: hiking travelling painting biking tours ... what do we know from the exo-planets?