Corfu 10/9/07 ( HTRA: ~ 100 ms -- 1μs ) - To develop the most promising technologies for HTRA - Assess relative strengths/areas of application in astronomy JRA3: Technology development for high-time-resolution astronomy

Corfu 10/9/07 - Indicative budget 1.2 M€ - 3 main technology WPs - 4 ‘connective tissue’ WPs JRA3 Partners Max-Planck-Institut für Extraterrestrische Physik Institute of Astronomy, Cambridge National University of Ireland, Galway University of Warwick Sheffield University UK Astronomy Technology Centre, Edinburgh Landessternwarte Heidelberg Max-Planck-Institut für Astrophysik European Southern Observatory

Corfu 10/9/07 JRA3 1. Rapidly varying astronomical objects 2. Rapidly varying earth atmosphere (adaptive optics) Key requirement for high time resolution astronomy: single photon detection Need for high time resolution GX /5/04 FORS2 HITI 1 2 3s

Corfu 10/9/07 JRA3 WP4 Avalanche photodiode arrays WP2 EM-CCDs (L3CCDs) WP3 Avalanche amplified pn-CCDs WP5 CCD controllers WP6 Software WP7 Testbeds WP1 Management Contractors and workpackages NUIG Sheffield Warwick UKATC MPG/MPE ESO IoA, NOTSA MPG/MPA, LSW

Corfu 10/9/07 JRA3 Projected JRA3 spending by technology Avalanche photodiodes Electron multiplied CCDs Avalanche amplified PN CCDs ‘connective tissue’ 17% 40% 30% 13% ~

Corfu 10/9/07 JRA3 WP4 APD-array development National University of Ireland in collaboration with University College Cork Array elements have to be spatially separated (crosstalk) - to be fed with - lenslet arrays or - fibers Single detectors in use for HTRA and AO

Corfu 10/9/07 JRA3 n Fibre fed APD array ¨ Fibres epoxied by UV curing to APD devices ¨ Elimination of cross talk issue due to ¨ separated APD elements Individual fibres aligned on to APD dies in ceramic packages On-chip arrays APD arrays (WP4)

Corfu 10/9/07 JRA3APD arrays (WP4) Summary and perspective APD technology - known technology - limitations: cross-talk, dark current non-uniformity. - close to its technological limit - CCD-based technologies encroaching on its territory but... - still the only technology for highest time resolution

Corfu 10/9/07 JRA3 ● Conventional CCDs: spurious electrons on readout ● ‘EM’: On-chip electron multiplication ● Available now (E2V, TI) ● JRA3 activities: 1 Controller development for high time resolution applications - up to 60 Mpix/s 2 Application tests: - ‘Lucky images’: cheating the seeing limit - HTRA: rapidly varying objects - (photon counted spectra) L3CCDs (EM-CCDs) WP2, WP5, WP7

Corfu 10/9/07 JRA3‘Lucky images’ E2V EM-CCD + fast controller (WP5,6,2) 10% best framesall frames M13 Cat’s Eye

Corfu 10/9/07 JRA3 pulsar in crab nebula P=30 ms exposures 2 ms ‘Lucky images’

Corfu 10/9/07 Spectra with single-photon detection

Corfu 10/9/07 JRA3WP5 controllers for EM-CCDs Controller boards, vacuum interface & chip support

Corfu 10/9/07 JRA3 Summary and perspective EM-CCDs ● Best currently available technology ● Advances in controllers & data processing technology ● Shows the potential of photon counting CCDs for - high time resolution observations - angular resolution improvement by ‘lucky imaging’ - wavefront sensors for AO ● technology still developing rapidly

Corfu 10/9/07 JRA3 Avalanche-amplified pn-sensors (AA-pn) ● Alternative silicon technology for same purpose ● Developed at the semiconductor laboratory of the MPG, ● Initiated by JRA3 ● Technology elements produced and tested (Aug 2007) ● Prototype device by end of 2008 ● elements: - thick detection layer (0.5mm) - avalanche amplifier - AR coatings

Corfu 10/9/07 JRA3 Avalanche-amplified pn-CCDs (WP3)

Corfu 10/9/07 JRA3 Avalanche-amplified pn-CCDs (WP3)

Corfu 10/9/07 JRA3Avalanche-amplified pn-CCDs (WP3)

Corfu 10/9/07 JRA3Avalanche-amplified pn-CCDs (WP3) Differences ↔ E2V EM-CCD 1. Parallel readout + slower clock → lower readout noise → lower amplification factor → ● higher dynamic range and ● no internally generated photons 2. Deep depletion layer → ● near-IR wavelength sensitivity 3. AR coating technology: ● broader wavelength range

Corfu 10/9/07 JRA3Avalanche-amplified pn-CCDs (WP3)

Corfu 10/9/07 JRA3Avalanche-amplified pn-CCDs (WP3)

Corfu 10/9/07 JRA3 Summary and perspective AA-pn CCDs ● represents next generation electron-multiplied CCD technology - photon counting accuracy - wavelength range - IR sensitivity - time resolution (<1 ms) ● development on schedule ● full-scale CCD currently ‘in the oven’, functional tests mid ● prototype device and controller expected by end 2008

Corfu 10/9/07 JRA3 ‘connective tissue’ - camera head development (WP7, completed) - higher level software interfaces (WP6, under construction) - management (WP1)

Corfu 10/9/07 JRA3 UKATC high voltage clock (WP5)

JRA3 Corfu 10/9/07 WP 7 Cooled camera head (in ESO cryostat)

Corfu 10/9/07 JRA3 Management Main events since start of contract - Transfer of management from LSW Heidelberg to MPA (July 05) - Redefinition of technology contribution MPE (Feb 05) - Common hardware platform for comparison of technologies replaced by software procedure (Feb 05) - Definitive finance plan JRA3 approved by OPTICON board (Oct 05) Status August - 95% of work on track - Technologies successful beyond expectation - Major innovations achieved in high time resolution CCDs

Corfu 10/9/07 JRA3 Miles and deliverables (as of Aug 2007) achieved/delivered WP1 M1, M2, M3 WP2 M1, M2, D1 WP3 M1, M2, D1 WP4 M1 WP5 M1,M2,M3,D1 WP6 M1 WP7 M1, D1 WP8 M1 remaining D2 M3, D2 M2, D2 D2 D1 completed D1

Corfu 10/9/07 JRA3