1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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EddiCam: The Eddington Photometric Camera

Preliminary design

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam • EddiCam design drivers

– Integration times: 0.5 to 30 s

– Number of stars to be monitored simultaneously: up to few times 105

– White light (TBC!!)

– Duty cycle: > 90%

– High photometric accuracy. Noise induced by random perturbations (readout noise, jitter, thermoelastic stability, CCD thermal stability,....): < photon noise.

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

• Preliminary baseline design

– Ø 3° field of view (1.5° x 3° effective FOV in asteroseismology mode)

– 20 CCD mosaic – broad band (4000-9000 Å) coverage (white

light)

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

ROE/CCU PCE DPE

EddiCam Camera Unit

Power andsignals

Heat pipes +radiator

Primary mirror

Secondarymirror

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

EddiCam location

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

• EddiCam components– Focal Plane Assembly:

• CCDs array

• FEE

• Frame store buffer covers

• Calibration LEDs

• Shutter/cover

• Thermal control subsystem

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

• CCD baseline characteristics– Format: 740 x 2900 pixels

– Pixel size: 27 x 27 µm2

– Chip size: 20 x 80 mm2

– Full well capacity: 1.6 Me-

– Minimum line readout time: 13 µs

– Frame transfer time: 20 ms

– Readout noise: 10 - 15 e- at 0.5 MHz

– Operational temperature: -80 / -100 C

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

CCD read out noise as a function of readout frequency

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

• CCD array preliminary design– 16 + 4 CCDs covering the full FOV

– CCDs working in frame transfer mode for asteroseismology (short integrations on bright stars)

– CCDs working in full frame mode for planet finding(long integrations on weaker stars)

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

Planet finding CCD layout Asteroseismology layout

FiltersFrame transfer covers

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

• CCD mosaic proposed by Marconi:

– 20 CCDs on individual INVAR packages

– Each CCD individually mounted on a large INVAR

baseplate

– All CCDs within ±10 µm from the baseplate:

no individual focussing required

– Flatness variation < 3 µm from +20 to -100 C

– Butting gap around 500 µm

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

Prototype of CCD array proposed by Marconi

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

Detail of individual CCD chip package

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

Detail of XMM-EPIC 7 CCD mosaic

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

Wheel with 3 positions:

• closed

• open

• dispersive element

Proably feasible, but expensive......

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam – CCD Control Unit

• Integration time control• Full frame/transfer frame operation• CCDs windowing• CCDs binning• Selection of readout ports and speeds• Generation of CCDs clocks, bias and power supply

– Read Out Electronics• CCD readout• Digitization• Data transmission to Data Processing Unit

Simultaneously for 20 CCDs with 40 Mpixels

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

– Data Processing Electronics• Telecommand management of EddiCam

• Scientific onboard data processing (heavy!!)

• Generation of TM and communications with OBDH

– Power conditioning electronics• Conditioned power supply to CCU, FEE and ROE

(very stable and low noise!)

• Power supply for shutter, LEDs and covers

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

O B D H

D P E

P C E

C C U

R O E

F P A

L E D s

H e a t e r s

S h u t t e r

C C D s c o v e r

P S U R T U

2 0

C

C

D

s

F E E

S p a c e c r a f t

H K

P o w e r

H K

C t r lC t r l

C t r l

D ig i t a ld a t a

V id e o

C t r lB ia sC lo c ks

T MH K T C

H K

P o w e r

P o w e r

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam • Preliminar budgets

EddiCam elements Mass (kg) Size (mm) Power dissipation (W)

Camera Unit(including FEE)

26 250x250x350 27

CCU 15 350x180x400 20

ROE 15 350x180x400 80

PCE 5 150x180x100 10

Total 70 140

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam • The EddiCam Definition Working Group

Centro de Astrobiología — Instituto Nacional de Técnica Aeroespacial

Centre Spatial de Liège + Universite de Liège

Deutsches Zentrum für Luft und Raumfahrt (DLR-Berlin)

Institute of Space Sensor Technology and Planetary Exploration

Instituto de Astrofísica de Andalucía + Instituto de Astrofísica de Canarias

Leicester University + Mullard Space Sciences Laboratory (London)

Observatoire de Paris + DAPNIA / CEA (Saclay)

Universität Wien

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam Eddington Science Working Team

Project Scientist

EddiCamLead Scientist

EddiSDCLead Scientist

EddiCamScience TeamLead Scientist

EddiCamTechnical TeamProject Manager

Local Co-I Local Co-I Local Co-I

Local ProjectManager

Local ProjectManager

Local ProjectManager

Local ProjectManager

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

• EddiCam Definition Phase milestones– Mid July 2001: Official answer from ESA to the LoI.

– September 2001: Telescope studies kick-off

==> interaction between Telescope and EddiCam

– Summer - fall 2002: end of telescope, CCDs and mission studies.

– End of 2002: EddiCam preliminary design and system

specifications

– Spring 2003: preliminary requirements review (PRR)

==> start of Phase B launch in 2007/08!!

1st Eddington Workshop

. Córdoba, June 14th, 2001 J. Miguel Mas-Hesse

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Eddicam

DPEPCE

CCU ROE

SHUTTER

COVERSCCDs

HEAT PIPES

Incoming light

FEE

LEDs

HEAT PIPES

Heaters

EddiCamCamera Unit