optical detector systems at eso (projects completed or started since dfa2005)

DfA2009

Optical Detector Systems at ESO(Projects completed or started since DfA2005)

Dietrich Baade&

Andrea Balestra, Claudio Cumani, Sebastian Deiries, Mark Downing,

Christoph Geimer, Olaf Iwert, Roland Reiss, Javier Reyes,

and Mirko Todorovic

For more details see also www.eso.org/sci

1 / 18Dietrich Baade: Optical Detector Systems at ESO

DfA2009

Controller

Scientific Detector Systems

R&D Projects

Signal (Wavefront) Sensing


3 / 18DfA2009

New General detector Controller (NGC)

• Joint development of IR and Optical Detector Departments

• First preview at DfA2005

• First systems delivered to MUSE (24xCCD), KMOS (3xH2RG), SPHERE (1xH1, 2xH2RG), ZIMPOL (2xCCD); < 1 MHz

• High-speed versions for IR VLTI and WFS applications under test (e.g., 3 MHz: Raytheon Aquarius; 10 MHz: Selex eAPD)

• Compact optical WFS variant underway (e2v EMCCD220; 14 MHz)

NGC is the standard for all forthcoming ESO detector systems.

Dietrich Baade: Optical Detector Systems at ESO

See also: Talk by Meyer et al. (H/W) Talk by Stegmeier & Cumani (S/W)Poster # 12-B by Reyes et al. (AO)Demonstration at ESO HQ

DfA2009

Controller


R&D Projects



DfA2009

OmegaCAM

16k x 16k mosaic of 32 e2v CCD44-82 2k x 4k CCDs for one-degree imaging with the 2.6-m VLT Survey Telescope (VST) on Paranal

Instrument on Paranal; fully functional and waiting for commissioning call

However, one CCD arrived dead with an inner short

Concern: Similar, earlier incident with one of the OmegaCAM spare CCDs

Replacement in 11/2009 Iwert et al., DfA2005


DfA2009

X-shooter

• First ESO UV-to-IR (0.3-2.5 μ) instrument; three spectrographs / detector systems

• IR arm (1.02-2.48 μ; H2RG) uses IRACE

• For the optical, FIERA controller software defines 2 nearly fully independent virtual cameras on one common front-end electronics:

• UVB system (0.3-0.56 μ; MIT/LL CCID-20)

• VIS system (0.55-1.02 μ; e2v CCD44-82)

• Last FIERA and IRACE systems

• Delivered in 2008 (optical systems: M. Downing)


7 / 18DfA2009

MUSE (Multi-Unit Spectroscopic Explorer)

• Survey instrument for deep spectroscopic stock taking

• FoV: 1 arcmin x 1 arcmin (sampling: 0.2 arcsec x 0.2 arcsec)

• 24 spectrographs with one e2v 4k x 4k DD CCD231 each

• 0.4 Gpixels (50% more than OmegaCAM)

• Four 6-board NGC boxes – single system

• First unit delivered, serial production through 2011

• CCD PSF ~0.8 pixels

• ~50,000 spectra/exposure

Graded AR coating

Poster # 11-B (Reiss et al.)Dietrich Baade: Optical Detector Systems at ESO

DfA2009

ZIMPOL (SPHERE)

SPHERE: (Exo-)planet finderZIMPOL: Zurich Imaging Polarimeter

Image exo-planets using the polarization of the star light scattered off their surfaces (contrast: ~108 @1”)

• Two e2v CCD44-82 2kx4k detectors in frame-transfer mode (2x2 binning)

• kHz up/down line shift (“zebra” mask) synchronized with polarization modulator

• Frame rate: 1 Hz

• Delivery: 2009/2010 (Mark Downing)


FORS1 Giraffe UVES red VIMOS

Focal reducer Medium-resolution MOS

Echelle spectrograph Wide-angle MOS

2007 2009 2009 2010

Tek 2048EB4-12kx2k, 24 μ

e2v CCD 44-822kx4k, 15 μ20 μ std silicon

MIT/LL 2kx4k, 15 μ20 μ thick

e2v CCD 44-824x 2kx4k, 15μ20 μ std silicon

e2v CCD 44-822x 2kx4k, 15 μ

e2v CCD 44-822kx4k, 15 μ40 μ DD silicon

MIT/LL2kx4k, 15 μ40 μ high-res. silicon

e2v CCD 44-824x 2kx4k, 15μ40 μ DD silicon

1.3x increase in UVB response

Red responsedoubled; much reduced fringing

R/NIR response nearly doubled; much reduced fringing

Doubled R/NIR response & reduced fringing (TBC)

Roland Reiss Mark Downing Olaf Iwert / Nicolas Haddad

Nicolas Haddad / Mark Downing

Dietrich Baade: Optical Detector Systems at ESO 9 / 18DfA2009

Detector Upgrades of Existing Instruments

Reduced fringing (additional graded AR coating

- as in MUSE - is still better!)

Improved red QE

Standard silicon

Deep-depletion silicon

See also talk by Downing et al. on bulk-silicon (70 μ) CCDs

DfA2009

Controller


R&D Projects



Dietrich Baade: Optical Detector Systems at ESO

11:33:54

Scale: 0.32Position: 5

17-Dec-08

78.13 MM

DfA2009

Curved Detectors

Poster # 18-A (Iwert et al.)

Curved detectors enable optical designs not realistically feasible with flat detector plus field flattening lens.

Radius of curvature: 500 mm (goal: 250 mm)

CfT for feasibility study in preparation

Concave detectors

Rogers et al.Rogers et al. 2008 11 / 18

DfA2009

Ultrastable Cryostat

The E-ELT echelle spectrograph CODEX and its VLT predecessor ESPRESSO aim at stepwise advancing the accuracy of velocity measurements from the present ~100 cm/s to ~1 cm/s (= 0.02 mph).

Top scientific aim: Model-independent measurement of the expansion history of the Universe.

Poster # 17-A (Iwert et al.)

Requirements on detector stability are formidable :

~100 pm or ~1 Si atom

Adam Riess


Dietrich Baade: Optical Detector Systems at ESODfA2009

UV QE Enhancements

The QE of a wide range of CCDs responds positively to baking in dry air and simultaneous UV flooding.

Long storage under high vacuum can have similar effect.

More data have been collected since DfA2005. One possible explanation invokes the removal of H2O (or H+) from the AR coating.

Poster # 09-A (Deiries et al.)

UV-bright surface features on some devices seem to resist degradation of the UV response: (still unknown) key to H2O-tight seal?

350 nm 13 / 18

DfA2009

Controller


R&D Projects



DfA2009

Wavefront Sensors for Adaptive Optics AO: Multi-conjugate Adaptive Optics Demonstrator (MAD)

• 3 + 2 detector heads (e2v CCD39; 80x80 pixels)

• Up to 400 fps (500 fps with 2x2 binning); RON: ~ 6-7 e-

• With DSP optimization, original FIERA spec of 1 Mpix/s much exceeded

• Delivered in 2007 (Roland Reiss)

► AO enables quantitative improvements

Globular Cluster NGC 6388 with 2 populations

JupiterMoretti et al. (2009, A&A, 493, 539)

MAD@VLT + HST HST

15 / 18Globular Cluster NGC 6388

DfA2009

Wavefront Sensors for Adaptive Optics@VLT: OCam and e2v CCD220/219

• e2v L3 Vision CCD220

• 240x240 pixels, up to 1500 fps

• 15 systems for VLT AO Facility 2010-

2012StoreArea

Image Area

240x12024□µm

StoreArea

Image Area

240x12024□µm

OP 1

OP 2 GainRegisters

OP 3

OP 4 GainRegisters

OP 8GainRegisters

OP 7

OP 6GainRegisters

OP 5

StoreAreaStoreArea

Image Area

240x12024□µm

StoreArea

Image Area

240x12024□µm

OP 1OP 1

OP 2 GainRegisters

OP 2 GainRegisters

OP 3OP 3

OP 4 GainRegisters

OP 4 GainRegisters

OP 8GainRegisters

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OP 7OP 7

OP 6GainRegisters

OP 6GainRegisters

OP 5OP 5

Test controller OCam developed by 3 institutes in France, in close cooperation with ESO.

RON: < 1 e- (w/ gain)See talk by Feautrier et al.and demonstration at ESO HQ

Transfer of OCam analog electronics to NGC underway.

See Poster # 12-B by Reyes et al.

CCD

CCD


NGC AO head

17 / 18

DfA2009

Wavefront Sensors for Adaptive Optics: The E-ELT Case

• For 8-m class telescopes, AO is an efficiency booster.

• For ELTs, AO is an enabling technology.

• E-ELT: o 84x84 Shack-Hartmann lenslets, each feeding 20x20 pixels o LARGE pixels: 20-24 μ o Frame rate 100 – 700 Hz

o RON < 3 e- rms

• Feasibility studies and pixel-design demonstrators with industry.

• CMOS is the likely technology.

• Released Call for Tenders for baseline device for use with natural guide stars.

For more about AO@ELTs see talk by Downing et al.Dietrich Baade: Optical Detector Systems at ESO

Dietrich Baade: Optical Detector Systems at ESODfA2009

Summary of (Optical) Detector Trends @ ESO

• Complexity of design and operation increasing

• Growing volume of parameter space (speed, noise, stability, etc.)

• Multiple units – serial production

• Much improved red QE with thicker devices

• Future ESO detector systems based on NGC

• Growing importance of signal sensing Growing importance of signal sensing

• CMOS technology making its way into optical CMOS technology making its way into optical

astronomyastronomy

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Photo: Stéphane Guisard (ESO) 18 / 18

optical detector systems at eso (projects completed or started since dfa2005)

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