1. Optical Detector Systems at the European Southern Observatory
Dietrich Baade
&
Optical Detector Team (ODT)
Work at ESO on infrared detectors covered in:
Dorn et al.
Finger et al.
Mehrgan et al.
Beletic et al.
Dietrich Baade & ODT: Optical Detector Systems at ESO

2. The ODT Themes VLT 2nd generation instruments:
X-shooter – the 0.3-to-2.4 μm rapid-response spectro-cannon
MUSE – the cosmic inventory taker
VLT projects in their own right but with an additional view of
getting ready for OWL:
Shift in emphasis from scientific imaging to signal sensing: Without AO, ELTs will not bring any improvement.
The MAD adaptive optics system tests enabling technology with bright natural guide stars.
The OPTICON project with e2v L3 Vision technology aims to push this towards the ultra-low noise domain.
The New General detector Controller (NGC) is a key stepping stone.
More to come
OmegaCAM for the VLT Survey Telescope (VST)
Dietrich Baade & ODT: Optical Detector Systems at ESO

3. Multi-conjugated Adaptive Optics Demonstrator
MAD tests two wavefront-sensing (WFS) concepts:
star oriented, using multiple Shack-Hartmann (SH) systems
layer oriented (LO), using multiple pyramids
3 SHWFS + 2 LOWFS detector systems with
e2v CCD39 devices (80 x 80 pixels)
Only one method used at a time
One FIERA controller
Up to 400 frames/s (500 frames/s with 2x2 binning)
Considerably exceeds original FIERA spec of 1 Mpixel/s
Read noise: ~7 e-
Reiss et al.
Dietrich Baade & ODT: Optical Detector Systems at ESO

4. Next-generation Wavefront Sensing: OPTICON and e2v L3 Vision Technology
AO systems for 2nd-gen. VLT instruments and OWL require:
>1,000 actuators (→ >1,000 x 6x6 pixels)
~1 kHz frame rate
negligible read noise even when photon noise ~100%
high movability (→ no real cryogenics → dark current)
OPTICON project received funding from EU Commission
CCD220 being developed by e2v
1 system foreseen for HAWK-I, 4 for MUSE
Downing et al.
Dietrich Baade & ODT: Optical Detector Systems at ESO

5. OmegaCAM (1° x 1° imager)
Three FIERAs and 32 (+4) e2v CCD44-82 devices
Very robust since first switch-on
The coordination of autoguiding, closed-loop wavefront sensing, and shutter control is one of the show pieces.
Built as designed
Commissioning in 2006
Strict attention to safety
Extensive detector characterization on ESO’s test bench
Innovative cooling system very effective
Iwert et al.
Christen et al. (2x)
Lizon et al.
Dietrich Baade & ODT: Optical Detector Systems at ESO

6. X-shooter
Basically a single-mode VLT Cassegrain instrument for singular events (`point and shoot´)
Simultaneous wavelength coverage 0.3 – 2.4 μm
First ESO instrument to bridge the 1-micron barrier
2 optical arms (e2v CCD44-82 and MIT/LL CCID-20)
1 IR arm (Rockwell Hawaii-2 RG)
1 IRACE and 1 FIERA controller each
FIERA software defines 2 fully
independent virtual cameras on one common DFE
Approaching Final Design Review
Commissioning in 2008
Dietrich Baade & ODT: Optical Detector Systems at ESO

7. Multi-unit Spectroscopic Explorer (MUSE)
Twenty-four separate detector systems
4K x 4K CCDs (or 2 x 1 mosaics)
465 – 930 nm: high red response is mission critical
Need to save mass and volume
Must ease AIT
Reliability will be vital
First optical instrument to use NGC
2nd-generation cryostat head
Prototype detector system at the end of 2006
Reiss et al.
Dietrich Baade & ODT: Optical Detector Systems at ESO

8. Cryostat Cleanliness and Control
Plasma cleaning:
fast, effective, low risk, low operating cost
excellent results with big OmegaCAM cryostat
Deiries et al.
H20 exorcism
baking of CCDs in gas stream
accidental (re-)discovery
PULPO2 housekeeping unit with enhanced
shutter ( ) and temperature control
temperature and pressure monitoring
Reif et al.
Geimer et al.
Dietrich Baade & ODT: Optical Detector Systems at ESO

9. New General detector Controller (NGC)
In the decade since 1998, a total of 30 FIERA and IRACE systems will be deployed.
Extremely successful (nearly negligible telescope downtime) but some other limitations:
mass, volume, power dissipation
obsolete components
voltage range and swing
speed, number of channels
2 successes (= 2 costs)
Proto-type of joint successor NGC has seen `first light´
First deployments: KMOS (2009) and MUSE (2011)
Meyer et al.
Cumani et al.
Reyes et al. a
Dietrich Baade & ODT: Optical Detector Systems at ESO