NIRSPEC-IFU Management Meeting LAM – ESA – ASD 15/10/04

Introduction Meeting called by ESA and ASD Meeting called by ESA and ASD Request to LAM to change implementation approach Request to LAM to change implementation approach Demonstrate IFU can be delivered in specs Demonstrate IFU can be delivered in specs Demonstrate IFU can be delivered in time Demonstrate IFU can be delivered in time Capitalize on on-going development Capitalize on on-going development Redefine industrial team Redefine industrial team Design and development approach Design and development approach

NIRSPEC IFU Development History I. LAM has demonstrated that integral field spectroscopy is required for NIRSPEC LAM has demonstrated that integral field spectroscopy is required for NIRSPEC 3D approach ( , ,λ) is a very powerful science tool 3D approach ( , ,λ) is a very powerful science tool Used on ground based observatories Used on ground based observatories Included in the NGST “Design Reference Mission” as optional instrument following our studies Included in the NGST “Design Reference Mission” as optional instrument following our studies LAM has developed IFU concept under ESA contracts, over more than 6 years LAM has developed IFU concept under ESA contracts, over more than 6 years Needed to develop the technology and qualify for space Needed to develop the technology and qualify for space Today: intense LAM R&D has led to the space qualification of a revolutionary new technique, modulo a few remaining items Today: intense LAM R&D has led to the space qualification of a revolutionary new technique, modulo a few remaining items A unique worldwide know-how A unique worldwide know-how LAM key partner for SNAP, TMT (30m), ESO-ELT, OPTICON LAM key partner for SNAP, TMT (30m), ESO-ELT, OPTICON IFU on NIRSPEC: a very visible item on-board JWST IFU on NIRSPEC: a very visible item on-board JWST

Slicer Principle 1.Field divided by slicing mirrors in subfields telescope pupil on the pupil mirrors 2.Aligned pupil mirrors 3.Sub-field imaged along an entrance slit How to rearrange 2D field to enter spectrograph slit: Courtesy: JR Allington Smith

IFU techniques: implemented and work on 4-8m ground based telescopes Several IFUs in operation Several IFUs in operation ESO-VLT, VIMOS ESO-VLT, VIMOS Build by LAM Build by LAM Gemini Gemini WHT WHT CFHT CFHT 1/8th VIMOS IFU Spectra λ

Key “historical” points LAM has created a unique robust IFU optical design LAM has created a unique robust IFU optical design No competitor worldwide in visible - NIR No competitor worldwide in visible - NIR LAM has been an essential contributor to NIRSPEC design. LAM has been an essential contributor to NIRSPEC design. Optical concept from LAM Optical concept from LAM Has helped ASD to focus on proper design analysis (Phase A “crisis”) Has helped ASD to focus on proper design analysis (Phase A “crisis”) LAM has been a key partner for ASD to win NIRSPEC contract LAM has been a key partner for ASD to win NIRSPEC contract Essential expertise at LAM not present at ASD Essential expertise at LAM not present at ASD Excellent partnership over 6 years Excellent partnership over 6 years

NIRSPEC & IFU Development steps IFMOS: ESA-LAM contract ASD sub-contractor IFMOS2: ESA-ASD contract LAM sub-contractor NIRSPEC pre-Phase A: LAM contract ESA-ASD sub-contractor NIRSPEC Phase A: ESA-ASD contract LAM sub-contractor NIRSPEC pre-Phase B: ESA-ASD contract LAM sub-contractor Payload Study: ESA-ASD contract LAM sub-contractor NIRSPEC-IFU prototype: ESA-LAM contract

What did we secure ? A unique optical design A unique optical design Demonstrated to be valid by prototype image quality √ Demonstrated to be valid by prototype image quality √ A robust implementation concept inside NIRSPEC √ A robust implementation concept inside NIRSPEC √ No moving parts, Input FOV selected by MSA No moving parts, Input FOV selected by MSA A unique manufacturing technology √ A unique manufacturing technology √ Micro-optical components of very high quality: Thin glass slices, optical bounding Micro-optical components of very high quality: Thin glass slices, optical bounding Successful R&D with Cybernetix Successful R&D with Cybernetix A prototype has been build A prototype has been build Complex optical system produces outstanding images, well within specs √ Complex optical system produces outstanding images, well within specs √ 2D to 1D demonstrated √ 2D to 1D demonstrated √ Individual components survive vibration tests √ Individual components survive vibration tests √ Overall opto-mechanical concept √ Overall opto-mechanical concept √ √ Optical bounding √ √ Unrestricted vibration tests √ What if MSA fails ??? √ What if MSA fails ??? √ IFU identified as a backup option IFU identified as a backup option

What are we missing ? System approach System approach Simulated dynamic opto-mechanical model Simulated dynamic opto-mechanical model Demonstrated vibration test survival Demonstrated vibration test survival Need to apply simulation results to notch appropriately Need to apply simulation results to notch appropriately Prototype was vibrated full-on without adequate notching ! Prototype was vibrated full-on without adequate notching ! Nevertheless, very limited breakage Nevertheless, very limited breakage Lesson from prototype vibration test very valuable Lesson from prototype vibration test very valuable Increment toward full success is small compared to existing development successes Increment toward full success is small compared to existing development successes A lot has been done A lot has been done Remaining validation work compatible with phase B Remaining validation work compatible with phase B

Why the harsh action from ASD and ESA ? ESA-ASD need 100% proof of success ESA-ASD need 100% proof of success Understandable managerial goal Understandable managerial goal Late delivery of prototype Late delivery of prototype But acknowledge successes on a complex development not so obvious to develop at start But acknowledge successes on a complex development not so obvious to develop at start Compare to other risky components like MSA: IFU in pretty good shape ! Compare to other risky components like MSA: IFU in pretty good shape ! Vibration test results are interpreted negatively Vibration test results are interpreted negatively But no acknowledgement of successes But no acknowledgement of successes LAM is not industry LAM is not industry We tell you everything ! We tell you everything ! We are motivated because we are users We are motivated because we are users Capabilities to react on immediate notice not so easy, but we are significantly cheaper Capabilities to react on immediate notice not so easy, but we are significantly cheaper Negative comments about CNRS are irrelevant Negative comments about CNRS are irrelevant Knowing us for 6 years, Astrium never raised the issue nor asked for a management meeting to discuss contractual arrangements Knowing us for 6 years, Astrium never raised the issue nor asked for a management meeting to discuss contractual arrangements Why does it come so late ? Why does it come so late ? Ample time to iterate on development approach if not satisfactory Ample time to iterate on development approach if not satisfactory Full cooperation spirit since 6 years ! Full cooperation spirit since 6 years ! New project managers New project managers

ESA ASTRIUM concerns ESA and Astrium presentation ESA and Astrium presentation

Technical Baseline I. Start from prototype

Entrance Pupil Slicer mirror Pupil mirrors Slit Mirrors Slicer unit optical design for the IFS IFU optical design: out of reach of industry, unique to LAM

Radius of curvature: ~ 150 mm Tilt in Y: +/- 3.7° Tilt in X: from 3.3 to 9° Thickness: 900 µm Width: 27 mm Slicer unit optical design for the IFS

300µm Pupil mirror pitch: mm Pupil oversizing in spectrograph: <2 Tilt Y: +/- 3.7° Tilt X: 3.65° –> 6° Curvature Radius: ~24.5mm Slicer unit optical design for the IFS: pupil mirror

500µm Pitch: mm Curv. radius: 26.5 mm Tilt Y: 0° Tilt X: 6.5° Slicer unit optical design for the IFS: slit mirror

Image Slicer : 1st design

Image Slicer : 2nd design After sine sweep tests and static load FEM analysis, a new design was implemented to ensure higher rigidity

Design Overview Active Stack Heel Stack support Steering mirror Pupil mirror array Slit mirror array Main structure Substructure Thrust cylinders Dummy Stack

The prototype as built

Slicer Stack Clamps 18 dummy slices 10 Active slices 2 Dummy slices Clamp

Mirrors lines

Tests

Image Slicer : Thermal tests

Image Slicer : Vibrations Tests

Development Results Highlights

Manufacture and integration

Ensquared energy

Crosstalk +/-40µm relative for a specification of +/- 120µm

Slits separation Plots of the intensity profiles in the regions between the pseudo-slits. Lowest contour in the plots corresponds roughly to ~1% of the peak intensity (50 for a peak intensity of ~3000).

From Sine sweeps (3 axis), we fit with a model of n SDOF : Image Slicer : Modal Analysis We get the main proper frequencies of the specimen, and associated damping or quality factor (Q)

SDOF parameters (F,Q) are input for NASTRAN dynamic FEM Model : Image Slicer :

Lessons

Prototype critical points Critical point Validation Fabrication of optical subsystem (slices, assembly, specifications) YES Vibration compliance of the sub-system YES Thermal compliance (+cycling) of sub-system YES

Prototype critical points Optical performances (PSF, Alignement, slit function,…) YES (alignement not checked after vibration) Mounting and alignment at operating temperature YES Vibration Compliance of the system Survived (Opto-mechanical defect) Thermal compliance (+cycling) of sub-system YES

Lessons Learned from the prototype development LAM Team R&T development spirit while the contract was more flight hardware delivery oriented ( ESA did not refocus during the study) LAM Team R&T development spirit while the contract was more flight hardware delivery oriented ( ESA did not refocus during the study) LAM experience in structural dynamic analysis not sufficient LAM experience in structural dynamic analysis not sufficient No internal review conducted before final and critical vibration tests and report delivery No internal review conducted before final and critical vibration tests and report delivery Estimates of delays not properly handled Estimates of delays not properly handled LAM needs external support LAM needs external support  But the prototype is finished and the core technology is validated

How to proceed for the NIRSPEC- IFU development Need of phase B/C/D industrial management type Need of phase B/C/D industrial management type Need support for dynamical analysis study Need support for dynamical analysis study LAM concentrates on optical development and tests LAM concentrates on optical development and tests  Refocusing on our core activities

Inspection Inspection Flakes are located at contact area with metallic (invar) stops Flakes are located at contact area with metallic (invar) stops Fretting corrosion marks at these locations Fretting corrosion marks at these locations Optical parts have moved No non-emerging cracks Analysis Analysis Geometry of contact area is not compatible with glass/metal contact criteria Geometry of contact area is not compatible with glass/metal contact criteria Location of stops is not optimized to loads repartition Location of stops is not optimized to loads repartition QSL dimensioning is not appropriate, end despite notching, as 5 sigmas levels found QSL dimensioning is not appropriate, end despite notching, as 5 sigmas levels found Solutions Solutions Improvement of the contact points between Zerodur and Invar Improvement of the contact points between Zerodur and Invar Avoid contact points near the edges of the Zerodur part Avoid contact points near the edges of the Zerodur part Compute the required forces to maintain the optics, then increase the force of springs Compute the required forces to maintain the optics, then increase the force of springs Image Slicer : post-vibration Expertise

Solutions Solutions Recompute force applied Recompute force applied Not strong enough Not strong enough Increase by x2-3 Increase by x2-3 Groove in metal Groove in metal Beveled edge on glass Beveled edge on glass Clamp on back support Clamp on back support Fused silica instead of zerodur ? Fused silica instead of zerodur ? Less brittle Less brittle Glass to metal Glass to metal Soft material Soft material Gold Gold Fixed spherical contact Fixed spherical contact Self adjusting spherical washer Self adjusting spherical washer Image Slicer : support solutions

Lateral breakouts on Zerodur pedestals can only be modelised with nonlinear elements (slipping and gap elements). Lateral breakouts on Zerodur pedestals can only be modelised with nonlinear elements (slipping and gap elements). This kind of sophisticated model can’t be used for classical random FEM analysis (with NASTRAN) This kind of sophisticated model can’t be used for classical random FEM analysis (with NASTRAN) non linear temporal analysis of deflections and stresses is under development. non linear temporal analysis of deflections and stresses is under development. Image Slicer : Non linear analysis

Foreseen Wrenching tests Foreseen Wrenching tests mirror Zerodur main support Adjustable mass Translation Stainless Steel ball (thrust) We have already performed a wrenching test, 3 time with the same specimen. We have obtained 3 time the same value (18N) We are working (in advance of phase) on a statistic study (33 specimen) to determine the optical bond strength. We are establishing a test plan and designing the tools. 1 st set up 1 st set up 2 nd set up 2 nd set up

Technical Baseline II. Proposed design

120 mm 64 mm 207 mm Overview

Entrance beam Slicer stackPupil mirrorSlit mirror Exit beam

Invar (frame and optical support) Optical elements in Zerodur Opto-mechanical mount TBD Kinematics mount TBD

Assembly philosophy Frame designed to support 3 sub-assemblies Each sub-assembly supporting optical elements can be set-up separately The interfaces are designed to guarantee a good positioning

Weight: Mechanics 810 gr baffling 250 gr optics 70 gr thermal sensors 12 gr Total 1212gr Weight

Industrial Team Assume LAM not prime Assume LAM not prime ESA and ASD critical ESA and ASD critical Goal oriented: fly the IFU on JWST Goal oriented: fly the IFU on JWST Build consortium with relevant industries Build consortium with relevant industries Knowledgeable about IFU technology Knowledgeable about IFU technology Long track record on space experiments Long track record on space experiments Does not exist today Be pragmatic Involve Cybernetix for responsibility in IFU delivery and performances around their core technical expertise Involve Cybernetix for responsibility in IFU delivery and performances around their core technical expertise Involve ASF for key support Involve ASF for key support

Proposed consortium Cybernetix Astrium Toulouse LAM

WBS: Phase B

WBS: Phase C/D

Share of work and responsibilities Cybernetix Cybernetix Overall management Overall management Responsible for the delivery of the IFU Responsible for the delivery of the IFU Responsible for the performances Responsible for the performances Mechanical design Mechanical design Optical and mechanical manufacturing Optical and mechanical manufacturing Integration Integration LAM LAM Responsible for optical architecture Responsible for optical architecture Optical analysis Optical analysis Prototype qualification Prototype qualification Responsible for breadboard tests Responsible for breadboard tests Responsible for FM tests Responsible for FM tests Astrium Toulouse Astrium Toulouse PA support PA support Design analysis Design analysis Optical and Hydroxyl bounding Optical and Hydroxyl bounding Detailed thermo-mechanical analysis Detailed thermo-mechanical analysis Thermo-mechanical tests Thermo-mechanical tests

LAM Project Team Gil Moreto Project Manager, 100% Eric Prieto Optical System, 50% Franck Ducret PA, 50% Sébastien Vives Optical analysis, 100% Nataly Manzone Project assistant, 50% Pierre-Eric Blanc Mechanical design, 100% Jean-Lucien Boit System engineering, 50% Christelle Rossin Mechanical analysis, 50% AIT Alain Origné, 50% Gérard Rousset PM, 50%

Related Experience Cybernetix Cybernetix PM: Did PhD at LAM on image slicers / IFS PM: Did PhD at LAM on image slicers / IFS Developed all the technology to produce high quality slices Developed all the technology to produce high quality slices Acquainted with ESA requirements, including PA Acquainted with ESA requirements, including PA Recent experience on several large ESA projects Recent experience on several large ESA projects Space station HW delivered Space station HW delivered Contractor for the DGA (military State Dept.) for military developments Contractor for the DGA (military State Dept.) for military developments Strongly motivated Strongly motivated

Related Experience LAM LAM Originator of IFU concept and design Originator of IFU concept and design Has build IFUs now in operation on the ESO-VLT Has build IFUs now in operation on the ESO-VLT Has led all the development up to now Has led all the development up to now Has 30years track record in the design, manufacturing, tests of space instrumentation hardware (HST, SOHO-Lasco, ISO, Rosetta, Galex, COROT, Hershell-Spire,…) Has 30years track record in the design, manufacturing, tests of space instrumentation hardware (HST, SOHO-Lasco, ISO, Rosetta, Galex, COROT, Hershell-Spire,…) Strongly motivated Strongly motivated

Related Experience Astrium Toulouse Astrium Toulouse You know them You know them Strongly motivated Strongly motivated

Design & development approach Phase B: Phase B: Design Design Analysis (optical performance, stray light analysis, structural static and dynamic, thermal) Analysis (optical performance, stray light analysis, structural static and dynamic, thermal) Test Plan preparation Test Plan preparation Technological development: Technological development: 30+3 optical bonding release (for statistical approach) 30+3 optical bonding release (for statistical approach) 30+3 Hydroxil bonding release 30+3 Hydroxil bonding release 40 slices stack with optical bonding (vibration, thermal, shock) 40 slices stack with optical bonding (vibration, thermal, shock) 40 slices stack with Hydroxil bonding (“”) 40 slices stack with Hydroxil bonding (“”) Opto-mechanical mount for pupil lines (thermal, vibration, shock) Opto-mechanical mount for pupil lines (thermal, vibration, shock) Opto-mechanical mount for flat folding mirror (thermal, vibration, shock) Opto-mechanical mount for flat folding mirror (thermal, vibration, shock)

Design & development approach Phase C/D: Phase C/D: STM: for dynamical model calibration, opto-mechanical demonstrator verification, and delivery at Astrium STM: for dynamical model calibration, opto-mechanical demonstrator verification, and delivery at Astrium EQM: end to end optically functional for 9 channels, structural fully representative, interface representative; qualification in vibration, optical performance at operating temperature, thermal cycling, and shock EQM: end to end optically functional for 9 channels, structural fully representative, interface representative; qualification in vibration, optical performance at operating temperature, thermal cycling, and shock FM: Environmental tests at acceptance level, acceptance optical test at operation temperature, characterization at operating temperature FM: Environmental tests at acceptance level, acceptance optical test at operation temperature, characterization at operating temperature

Model Philosophy

Technology development plan 33 samples of pupil mirrors optically bonded: 33 samples of pupil mirrors optically bonded: 33 acceptance tests 33 acceptance tests 33 cryo cycling (22°K) 33 cryo cycling (22°K) 30 tests up to release at atmosphere pressure 30 tests up to release at atmosphere pressure 3 tests up to release in vacuum 3 tests up to release in vacuum 33 samples of pupil mirrors hydroxil bonded: 33 samples of pupil mirrors hydroxil bonded: 33 acceptance tests 33 acceptance tests 33 cryo cycling (22°K) 33 cryo cycling (22°K) 30 tests up to release at atmosphere pressure 30 tests up to release at atmosphere pressure 3 tests up to release in vacuum 3 tests up to release in vacuum

Technology development plan 40 slices stack, optically bonded: 40 slices stack, optically bonded: 15 thermal cycling (survival - IFU-284) 15 thermal cycling (survival - IFU-284) Vibration qualification tests (survival - specification?) Vibration qualification tests (survival - specification?) Shock tests (survival - specifications?) Shock tests (survival - specifications?) 40 slices stack hydroxil bonded: 40 slices stack hydroxil bonded: 15 thermal cycling (survival - IFU-284) 15 thermal cycling (survival - IFU-284) Vibration qualification tests (survival - specification?) Vibration qualification tests (survival - specification?) Shock tests (survival - specifications?) Shock tests (survival - specifications?)

Technology development plan Opto mechanical mount of pupil mirror lines on INVAR: Opto mechanical mount of pupil mirror lines on INVAR: Representative zerodur support (similar mass than support plus pupil mirror) Representative zerodur support (similar mass than support plus pupil mirror) Opto-mechanical mount (representative) Opto-mechanical mount (representative) Vibration test (survival - specifications?) Vibration test (survival - specifications?) Thermal cycling (survival - IFU-284) Thermal cycling (survival - IFU-284) Shock test (survival - specifications?) Shock test (survival - specifications?) Opto mechanical mount of folding mirror: Opto mechanical mount of folding mirror: Representative element Representative element Opto-mechanical mount (representative) Opto-mechanical mount (representative) Vibration test (survival - specifications?) Vibration test (survival - specifications?) Thermal cycling (survival - IFU-284) Thermal cycling (survival - IFU-284) Shock test (survival - specifications?) Shock test (survival - specifications?)

Product Breakdown / procurement approach Image slicer: Image slicer: Slicer unit + pupil line + slit line Slicer unit + pupil line + slit line No opto-mechanical mount No opto-mechanical mount Test structure for Test structure for Folding mirror: Folding mirror: Mirror plus opto-mechanical mount Mirror plus opto-mechanical mount Test Test Toroidal mirrors: Toroidal mirrors: Two mirrors together Two mirrors together Optomechanical mount Optomechanical mount Test structure for Test structure for Structure: Structure: STM: refurbishing after tests STM: refurbishing after tests EQM + FM + Spare: to the same company EQM + FM + Spare: to the same company

Verification approach Sub system acceptance: Sub system acceptance: Slicer, mirror lines: vibration (level?) + thermal cycling Slicer, mirror lines: vibration (level?) + thermal cycling Folding mirror + mount: vibration (level?) + thermal cycling + Folding mirror + mount: vibration (level?) + thermal cycling + Toroidal mirrors: optical performances mounted Toroidal mirrors: optical performances mounted Slicer + pupil +slit: optical performance Slicer + pupil +slit: optical performance

Verification approach EQM: EQM:

Verification approach FM: FM:

Planning KO: Nov 30th KO: Nov 30th PDR: Sept 05 PDR: Sept 05 In phase with general NIRSPEC planning In phase with general NIRSPEC planning