Post on 30-Dec-2015
description
April 19, 2023 what do we know from the exo-planets?
Florian Rodler
What do we know about the exo-planets?
&How to detect direct signals
from exo-planets?
April 19, 2023 what do we know from the exo-planets?
Introduction
(1)201 confirmed planetary candidates + 14 confirmed planets found around solar-like stars and pulsars (in 175 planetary systems)
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April 19, 2023 what do we know from the exo-planets?
- RV: only minimum mass: MPlanet_min = MPlanet sini
- microlensing: estimation of planetary mass
→ companion a browndwarf (M>13 Mjup) ?
- transit + RV: i ≈ 90°.Exact mass determinationpossible: MPlanet_min = MPlanet .
Introduction
(1)201 confirmed planetary candidates + 14 confirmed planets found around solar-like stars and pulsars (in 175 planetary systems)
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April 19, 2023 what do we know from the exo-planets?
Introduction
(1)201 confirmed planetary candidates + 14 confirmed planets found around solar-like stars and pulsars (in 175 planetary systems)
exact determinationof mass needed!!!
- transit + RV: i ≈ 90°.Exact mass determinationpossible: MPlanet_min = MPlanet .
- astrometry (→ future)- transit + RV- direct imaging- reflected light (+RV)
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April 19, 2023 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)
0.5 AU
Hot Jupiter Mercury
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April 19, 2023 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)
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April 19, 2023 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!)
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April 19, 2023 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)
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April 19, 2023 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"
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April 19, 2023 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 ...
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April 19, 2023 what do we know from the exo-planets?
Transits
Atmosphere of the planet around HD 209458 (Charbonneau … 2001)-9
April 19, 2023 what do we know from the exo-planets?
TrES-1: thermal signature of atmosphere found (Charbonneau ... 2005)
Transits
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April 19, 2023 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 beimaged (< 0.1“)!
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April 19, 2023 what do we know from the exo-planets?
Burrows ... 2003)
wavelength (micron)
wavelength (micron)
Direct imaging
Planet 2M1207 (Chauvin ... 2005)
Star-planet flux ratio decreased- for young objects (self-lum.)- in the NIR
Close-in planets can hardly beimaged (< 0.1“)!
Flu
xF
lux
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April 19, 2023 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)
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April 19, 2023 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 fora Jupiter sized planet!?
log distance from host star
0.05 0.5 5 [AU]
hot Jupiters
E J
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April 19, 2023 what do we know from the exo-planets?
Reflected light
High resolution, high S/N spectroscopyof 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 ...
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April 19, 2023 what do we know from the exo-planets?
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schematics ...
April 19, 2023 what do we know from the exo-planets?
0.5 AU
Hot Jupiter MercuryRequirements
• bright host stars (spectroscopy!)
• hot Jupiters (periods of 3-5 days)
• and lots of data (S/N)!
Reflected light
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April 19, 2023 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
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April 19, 2023 what do we know from the exo-planets?
Find planetary signature:
chi2 minimisation
→ calculate fits for K and contrast
→ best fit for planet
→ significance of detection: MC
Reflected light
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April 19, 2023 what do we know from the exo-planets?
Conclusions on direct methods
(a)transits atmospheres (VIS, IR), young and old radii moons!? i ≈ 90°
(b) direct imaging atmospheres (IR), young objects only not close to star
(c) reflected light atmospheres (VIS), old objects only very close to star bright objects
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April 19, 2023 what do we know from the exo-planets?
some stuff about Florian Rodler ...
Studies at Vienna observatory (1997 - ???), AustriaPhD student at MPIA, supervised by Martin Kürster
Topics of interest:beer & dancingatmospheres of exo planets, direct detectionspulsating starsobserving
Hobbies:hikingtravellingpainting biking tours...