PLATO Data Center:Purpose and Structure

Laurent Gizon (PDPM)

Hamed Moradi (PDC Project Office)

The PDC is in charge of the validation, calibration, and analysis of the PLATO observations.

It delivers the final PLATO science Data Products.

SGS Structure

• Mission Operations Center (MOC, flight-critical) Mission Operations Center (MOC, flight-critical) • Science Operations Center (SOC, mission-critical)Science Operations Center (SOC, mission-critical)• PLATO Data Center (PDC, science-critical)PLATO Data Center (PDC, science-critical)• Science Preparatory Activities (scientific Science Preparatory Activities (scientific

specification of software) specification of software)

PLATO Ground Segment

Operations Ground

Segment

Mission Operations

Centre

Ground Station Network

Science Ground

Segment

Science Operations

Centre

SOC

PLATO Data Center

PDC

PLATO Science

Preparation Management

PSPM

• The definition phase objectives of the SGS are to establish the technical (PDC) and scientific (PSPM) requirements baseline for the SGS and to develop the operations concept, architecture and interfaces.

• The definition phase activities of the PDC and PSPM are organized according to the following guidelines:

– PSPM provides the scientific specifications of the software– PDC translates the scientific specifications into technical specifications– PDC implements the technical specifications– PSPM checks that the PDC software is consistent with the initial

scientific specifications. This validation by PSPM occurs within the PDC – a normal part of the development QA process.

Data Levels• Telemetry: Baseline: 109 Gb/day uncompressed (8.7 Mb/s

compressed, during 3.5 hr each day).

• Level 0: Depacketized light curves, centroid curves, and selected imagettes (~1600), for each telescope (32+2)

• Level 1: Analysis of imagettes to validate and optimize performance of on-board treatment. Implementation of on-ground instrumental corrections, such as CCD corrections and jitter corrections. Then computation of average light curves and centroid curves for each star (science-ready). 

• Level 2: PLATO science Data Products (next table). Final DP is a list of confirmed planetary systems, fully characterized by the transit curves, the stellar seismic parameters, and the follow-up observations. High scientific added value.

PLATO Data Products

L2DP6Confirmed planetary systems and their characteristics

L2DP5Stellar masses and ages

L2DP4Stellar rotation and activity

L2DP3Asteroseismic mode parameters

L2DP2Planetary transits and their parameters

L1DP1Calibrated light curves and centroidcurves

Ancillary Observations

• Essential information for the success of the mission: input catalog, follow-up observations, etc.

• Support for on-board processing, on-ground calibration, and scientific data analysis

• Stellar properties: effective temperature, absolute luminosity, radius [Gaia], chemical abundances, v sin i, activity, properties specific to multiple stars.

• Follow-up observations to confirm planets (at several wavelengths when possible)

• Other relevant complementary observations: hires spectra, astrometry, imaging, spectro-polarimetry, etc..

• The ancillary data are in support of the processing activities and are accessed by the PDC via the main data base.

Ancillary observations:

star catalogsstellar parameters

follow-up observationsspectroscopy

radial velocitiesinterferometry

astrometry (Gaia)

DP0

DP1

DP5

DP4DP3 DP2

DP6

Exoplanet Analysis System

• Main Data Base centralizes DPs and ancillary data (PDC-DB @ MPS)

• PDC develops and implements code at ESA SOC to produce DP1

• Data Processing Centers (PDPCs) manufacture DP2-DP6

• Distribution of DPs and long term archive under SOC responsibility

PDC Architecture

PLATO Instrument Manager

MOC

SOC

PDCL. Gizon, MPS

Stellar Analysis System

T. Appourchaux, IAS

data treatment Algorithms

R. Samadi, LESIA

main database & system architecture

R. Burston, MPS

Exoplanet Analysis SystemN. Walton, IoA

science activities

data treatment implementation

I. Pardowitz, MPS

PLCScience Team+PDPM

ancillary databaseR. Burston, MPS

data accesscoordination

SOC includes a processing center for the validation and calibration of the data

ESA overall coordination (oversight) of science data releases, data access

and distribution

PDC designs and implements software to be run at the SOC

PDC WBS

1 Central Data Base

5 Data Processing Centers

WP32 Data Processing Algorithms (Talk by Samadi)

WP35 Ancillary Data Management(Talk by Deleuil)

WP36 Exoplanet Analysis System(Talk by Walton)

WP37 Stellar Analysis System(Talk by Appourchaux)

WP31 System architectureand main database (Burston)

• System architecture, archives, data base, System architecture, archives, data base, system managementsystem management

• Data flow design and management, export Data flow design and management, export system, networksystem, network

• Simulation of data streamSimulation of data stream

WP33 Data Processing Development (Pardowitz)

• Write and implement core-processing software that will run at the SOC

• Requires a good understanding of system interfaces with SOC and operational procedures

• For phase A, study jitter correction to prove feasibility

WP34 Input Catalog (Giommi)

• Implementation of the PLATO input catalogue, under Italian responsibility.

• This activity is related to the target and field characterization activity in the PSPM segment of the PMC.

• WP34 delivers the validated PIC to the PDC-DB

WP38 Data Analysis Support Tools (Gizon)

• PDC documentation management • Tools to support the analysis of individual light

curves and to provide feedback to L2 processing pipelines (exoplanet and stellar).

• PDPC-M is the place were consortium scientists inspect light curves, assess DP validity and update ranking of planet candidates

• Search tools and VO activities• Internal PDC web site• In particular, PDC web site makes FU info

accessible to FU observers

Time table

• Regular meetings with ESA to specify interfaces PDC-SOCRegular meetings with ESA to specify interfaces PDC-SOC• End Feb 2011 End Feb 2011 5 5thth PDC Meeting in K-Lindau. Identify final PDC Meeting in K-Lindau. Identify final

problems. Invite PSPM Leaders.problems. Invite PSPM Leaders.• WP Leaders deliver reports to LG by March 2011WP Leaders deliver reports to LG by March 2011• PDC document delivered to PCL in May 2011PDC document delivered to PCL in May 2011• June 2011: Decision on PLATO selectionJune 2011: Decision on PLATO selection• End June 2011, Phase B1 meeting.End June 2011, Phase B1 meeting.• December 2011: End phase B1December 2011: End phase B1

• November 2018: Launch of PLATONovember 2018: Launch of PLATO• 3+2+1 years in space3+2+1 years in space• Several releases of DPs during and after space mission Several releases of DPs during and after space mission • PDC must remain operational up to ~3 yrs after the end of PDC must remain operational up to ~3 yrs after the end of

the space mission in order to confirm last planets.the space mission in order to confirm last planets.

Cost

Thank you

Data validationData validation

– Validate onboard software: Validate onboard software: • Check onboard processing using ground copy of Check onboard processing using ground copy of

onboard software and the imagettes of ~1600 starsonboard software and the imagettes of ~1600 stars• Validate distortion matrix model, 2D sky background Validate distortion matrix model, 2D sky background

model, PSF model fitsmodel, PSF model fits• Validate computation of masks and windows Validate computation of masks and windows

– Validate onboard setup:Validate onboard setup:• Fine tuning of onboard software algorithm. For Fine tuning of onboard software algorithm. For

example choose number of parameters needed to example choose number of parameters needed to describe PSF. Especially during configuration mode.describe PSF. Especially during configuration mode.

– Monitor health of each telescope and assess Monitor health of each telescope and assess quality of the dataquality of the data

Data correctionsData corrections

– CCorrection for jitter. Performed independently for each orrection for jitter. Performed independently for each telescope; requires PSF knowledge, stellar catalog, and telescope; requires PSF knowledge, stellar catalog, and distortion matrix.distortion matrix.

– Integration time correction, sampling time correctionIntegration time correction, sampling time correction– Statistical analysis over the 40 telescopes to identify Statistical analysis over the 40 telescopes to identify

cosmic ray hits, hot pixels, and possibly deficient cosmic ray hits, hot pixels, and possibly deficient telescopestelescopes

– Average light curves and centroid curves over all Average light curves and centroid curves over all telescopes (weighted average).telescopes (weighted average).

– Compute error based on scatterCompute error based on scatter– The ~1600 stars for which imagettes are available receive The ~1600 stars for which imagettes are available receive

a more sophisticated treatment. PSF fits to improve a more sophisticated treatment. PSF fits to improve photometry (contamination from neighboring sources photometry (contamination from neighboring sources taken into acount). taken into acount). Imagettes are downloaded for all Imagettes are downloaded for all stars for which a serious planetary candidate has been stars for which a serious planetary candidate has been identified. identified.

– Long term detrending probably moved to PDCLong term detrending probably moved to PDC

Data volumesData volumes

• Telemetry rate: 109 Gb/day uncompressedTelemetry rate: 109 Gb/day uncompressed• Over a 6 yr mission: 30 TB uncompressedOver a 6 yr mission: 30 TB uncompressed• The volume of archived L0, L1 and HK data is The volume of archived L0, L1 and HK data is

expected to be 10-50 times this amount (reformatting expected to be 10-50 times this amount (reformatting and calibration history), i.e. 300-1500 TBand calibration history), i.e. 300-1500 TB

• The volume of the science data products is likely to The volume of the science data products is likely to be negligible in comparison (although the complexity be negligible in comparison (although the complexity of the data may be high).of the data may be high).

• Ancillary data base: basic stellar observations and Ancillary data base: basic stellar observations and parameters, spectra, Gaia specific obs, etc. How big?parameters, spectra, Gaia specific obs, etc. How big?

The overall data volume should not exceed a few PB, The overall data volume should not exceed a few PB, which is not problematic. which is not problematic.