PLAnetary Transits and Oscillations of stars http://www.oact.inaf.it/plato/PPLC/Home.html - Ultra-high precision photometric space mission - Candidate M-class mission in ESA Cosmic Vision programme
PLAnetary Transits and Oscillations of stars
http://www.oact.inaf.it/plato/PPLC/Home.html
- Ultra-high precision photometric space mission
- Candidate M-class mission in ESA Cosmic Vision programme
Main objectives:1. detect and characterize exoplanets of all kinds around stars of all types and all ages
including telluric planets in the habitable zone2. provide full observational basis to study stellar evolution3. enable very wide additional science programme: stellar rotation, stellar activity, binarity,
circumstellar environments, etc.
Three complementary techniques:- photometric transits : Rp/Rs (Rs known thanks to Gaia)- groundbased follow-up in radial velocity : Mp/Ms
- seismic analysis of host-stars (stellar oscillations) : Rs, Ms, age> measurement of radius and mass, hence of planet mean density> measurement of age of host stars, hence of planetary systems
Tool:- ultra-high precision, long, uninterrupted, CCD photometric monitoring of very large
samples of bright stars: CoRoT - Kepler heritage - bright stars: capability of seismic analysis and efficient groundbased follow-up
PLATO Science Objectives
- very large number of targets
- bright and very bright stars
- very long term monitoring
- ultra-high precision photometry
The PLATO challenge
8.0 x 10-5 in 1 hr for marginal transit detection (faint targets)
1 R⊕ planet transiting a solar-like star at 1 AU - mean of 3 transits
Noise level requirements for PLATO
3.4 x 10-5 in 1 hr for high S/N transit measurement: also required for seismic analysis
noise = 2.7 x 10-5 in 1 hr
noise = 4.0 x 10-5 in 1 hr
noise = 6.2 x 10-5 in 1 hr
noise = 8.0 x 10-5 in 1 hr
Noise level requirements for PLATO
3.4 x 10-5 in 1 hr sufficient for seismic analysis
CoRoT observation of a G type star: noise level = 3.4 x 10-5 in 1 hrduration 3.2 months Δν accuracy 1.2 µHz
PLATO target samples> 20,000 bright (~ mV≤11)
cool dwarfs/subgiants (>F5V&IV):
exoplanet transits AND
seismic analysis of their host starsAND
ultra-high precision RV follow-up
noise < 3.4 10-5 in 1hr for 3 years
> 245,000 cool dwarfs/subgiants (~ mV≤13)
exoplanet transits + RV follow-up
>1,000 very bright (mV≤8)
cool dwarfs/subgiantsfor 3 years
>3,000 very bright (mV≤8)
cool dwarfs/subgiantsfor >5 months
exoplanets
around bright and nearby stars
Main focus of PLATO:Bright and nearbystars !!
noise < 8.10-5 in 1hr for 3 years
> 5,000 nearby M-dwarfs (mV≤15)noise < 8. 10-4 in 1hr for 3 years
+ > 5,000 for 2-5 months
+ lists of additionaltargets presentingspecific interest
Instrumental Concept
- 32 « normal » cameras : cadence 25 sec- 2 « fast » cameras : cadence 2.5 sec, 2 colours- pupil 120 mm- dynamical range: 4 ≤ mV ≤ 16
optical field37°
4 CCDs: 45102 18µm « normal » « fast »
focal planes
fully dioptric, 6 lenses + 1 window
Very wide field + large collecting area :multi-instrument approach
optical design
On board data treatment: 1 DPU /2 cameras + 1 ICU Science ground segment
Orbit around L2 Lagrangian point, 6+2 year lifetime
Concept of overlapping line of sight4 groups of 8 cameras with offset lines of sight
offset = 0.35 x field diameter
8 8
8 8
16
16
16 16
2424
2424
32
Optimization of number of stars at given noise levelAND of number of stars at given magnitude
37°
50°
~ 50% of the sky !
0 °
30°
60°
90°
120°
150°
180°
210°
240°
270°
300°
330°
0h2h4h6h8h10h12h14h16h18h20h22h
CoRoT CoRoT
Kepler PLATO
PLATO
1. two long pointings : 3 years or 2 years2. « step&stare » phase (1 or 2 years) : N fields 2-5 months each
Observation strategy and sky coverage
Expected performances
as a function of noise level
as a function of magnitude
88,0009.8 - 11.322,00034
20,000 deg2
118
13.6
11.2
mV
1,30030
25,000
1,300
nb of cool dwarfs& subgiants
KEPLER (100 deg2)PLATO (4300 deg2)
145,0005,000
1,000,000
60,000
nb of cool dwarfs& subgiants
incl. step&stare
1136,00081,300
11.6 - 12.9292,00080
9.3 - 10.815,00027
mVnb of cool dwarfs& subgiants
long monitoring
noise level(ppm/√hr)
20,000
245,000
1,000 3,000
cf presentation by Giampaolo Piottothis afternoon
ESA project team
End-to-end Simulator
W. Zima
PLATO PayloadManagement
PIPM: P. Bodin
PDCPDPM: L. Gizon
Instrument SystemCoordinatorP. Levacher
Science Coordination
H. Rauer
Target/field Characterization
G. Piotto
FU Coordination
S. Udry
Stellar Science M.J. Goupil
Exoplanet scienceD. Pollacco
TOUR. Ragazzoni
Fast DPUG. Peter
Normal DPUPh. Plasson
PLATO Mission Consortium Science PreparationManagement
AlgorithmsR. Samadi
Mission management
AEU S. Fredon
ICUR. Cosentino
Prototype& FM AIVP. Levacher
main / ancillary databasesystem architecture
R. Burston
exoplanet analysis System
N. Walton
data processing implementation
I. Pardowitz
stellar analysis systemT. Appourchaux
Input CatalogueP. Giommi
Data Centre
Normal TOUR. Ragazzoni
Fast TOUW. Benz
Project Manager
Project Scientist Science Team- 6 PMC members- 2 Legacy Scientists
PMC Board
ancillary database content management
M. Deleuil
data analysis support tools
L. Gizon
FPA/FEED. Walton/M. Mas
Hardware & boot softwareM. Mas
Application softwarePh. Plasson
PMC Lead
C. Catala
Camera ManagementD. Laubier
DPS ManagementB. Pontet
Payload
SOC
data processing algorithmsR. Samadi
Additional science W. Weiss
PLAnetary Transits and Oscillations of stars
http://www.oact.inaf.it/plato/PPLC/Home.html
Danke !
Expected noise levelshot noise + readout noise + background noise + jitter + digitization noise
27 ppm
80 ppm
800 ppm
fast cam
8 cam
16 cam24 cam 32 cam
jitter/confusion + background
photon noise
photon noise limited up to mV=11
27 ppm up to mV=10.8
34 ppm
34 ppm up to mV=11.3