1. Athena Italian and CNES/IRAP Meeting
04th March 2015

2. Instrument Phase A activities
Phase A activities objectives
Demonstration Model focus
XIFU CNES/Partners teams proposed organization

3. Phase A activities objectives
The phase A activities will instrument and subsystems level from a technical point of view to:
Elaborate the preliminary specifications
Propose and perform the various trade-off in order to select the concept baseline and establish its feasibility
Propose the preliminary Mechanical, Thermal and Electrical (including redundancy concept) architecture
Identify the interfaces (internal & external I/F), in particular with the Payload Module
Identify potential constraints to be handled at Payload Module level
Propose preliminary operational concept for instrument in-orbit activities
Establish the Preliminary Performances Budget
Identify critical technologies and propose pre‐development activities
Compliant with the ECSS‐M‐ST‐10C

4. Phase A activities objectives
The phase A activities will instrument and subsystems level from a management point of view to:
Elaborate the Development and Verification plans (including model philosophy and verification approach) and the development planning for next phases
Elaborate the preliminary management plan and product assurance plan
Elaborate the risk assessment
Update the development cost
Consolidate the WBS
consolidation of the cooperation scenario
Phase A activities completion : mid 2017 with potential extension to end of 2017 to analyze potential output of ESA at the end of Phase A (A2).
Compliant with the ECSS‐M‐ST‐10C

5. Phase A activities : Close cooperation with ESA
Parallel Phase A activities of the Athena mission:
Phase A will be split in two sub-phases:
A Phase A.1 will be devoted to establishing high-level trade-offs and to defining the reference baseline for Athena. The plan is to study two configurations in the Phase A.1, and to close this phase by a dedicated independent review (the Mission Consolidation Review, MCR) The XIFU instrument is considered to be the same for these two configurations.
A Phase A.2 will be devoted to the consolidation of the Athena baseline, ending with a Preliminary Requirements Review.
The MCR will be followed by the issue of the AO for the instrumentation provision, with the attending selection of the payload consortia.
ESA AO is planned for July 2016 : partners contribution to the AO elaboration to be included within the frame of phase A activities.

6. Close cooperation with ESA technology development (Cosmic Vision)
Athena technology development activities in particular:
Detector cooling system including cryostat and active coolers down to 50mK
Optimization of a European Transition Edge Sensor array (As a back up solution)
Low vibration 15K Pulse Tube engineering model cooler including cooler drive electronics
2K Joule-Thomson engineering model cooler system including cooler drive electronics
Superconducting multilayer flex harness
Cryogenic vibration isolators and thermal disconnects

7. Phase A Activities : way forward
Engineering iterative process between Instrument team and partners :
Phase A Activities : the WP to be completed during phase A shall be prepared with the partners in order to fulfill the objective of the phase A activities presented here above. The goal is that convergence process between CNES and partners is finalized for beginning of june A detailed planning is required for Phase A and DM activities for partners contribution.
TRL assessment for the subsystem is planned to be reviewed in detail, and the critical technologies shall be identified in order to define the validation plan to be undertaken during phase A : mid September 2015
Preliminary Instrument Specification : V0 issued by instrument system team by 15/06/15. A two weeks process will be proposed for internal XIFU review (KP#1) in order to receive and discuss comments on this preliminary issue. Based on the accepted comments, V1 is due for 15/7/2015.

8. Phase A Activities : way forward
Preliminary Subsystem Specification : partners will provide inputs for the Specification of the Subsystem they are in charge of at the beginning of the phase A activities in order to commonly prepare the first issue of the specifications. Once the Instrument Specification V1 is available, the subsystem specification are updated if needed and issue V0 is due for mid september One month process will be proposed for internal XIFU review (KP#2) in order to receive and discuss comments on these preliminary issues. Based on the accepted comments, V1 susbsystem Specification is due for 30/10/2015.
Preliminary interface definition will be established and validated at instrument level. These preliminary ICD will be submitted to the subsystem KP#2
Applicable documents from Payload : TBD

9. Phase A Activities : way forward
Proposed Organization :
The instrument system team is managed by the instrument manager. A progress meeting dedicated to the field of technical responsibility of each partner (detector, readout electronics..) will be arranged every two weeks by teleconference or visio with the technical representative. It is foreseen to arrange every three months a progress meeting in CNES with the Instrument System Team. The following day, the synthesis of the work performed on the previous period will be presented by all the Project Managers of XIFU
Part time of activities in Toulouse shall also be needed on a case by case basis.
The development of the instrument subsystems is under the Products Manager responsibility. Progress meeting will be arranged every two weeks by teleconference or visio with the Project Manager of the subsystem. It is foreseen to arrange every three months a progress meeting in the facility of the partners.
Progress meeting at instrument level and Progress meeting at subsystem level in the partner facility will be shifted by 6 weeks.
Progress meeting at instrument level could be an opportunity for a consortium (Board) meeting

10. Beginning of Phase A : Logic and iteration process

11. Demonstration Model Objectives:
To enhance X-IFU TRL to 5/6 at the end of 2018.
To give feedback to the development team after the DM integration and tests in order to complete preliminary definition of the instrument & subsystem prior to PDR (re-engineering) - end of 2019.
For the PDR review, the tests results are analyzed, and in case of improvement needed or anomalies encountered, additional Breadboarding activities will be identified.
In order to achieve the objectives of phase A and DM activities, it is essential that the funding of this program for the different partners is available to start to work in early 2015.
Assumptions:
Based on ESA Cryo-cooler CTP + additional critical parts necessary to test the full chain
On a case by case basis, additional prototypes will have to be build at subsystems or equipment levels to raise TRL to 5/6.

12. Demonstration Model
The DM, from a thermal point of view, shall :
Demonstrate the thermal performances of the different cooling stages, in for what concerns the absolute temperature of the FPA, the associated stability and the resulting duty cycle.
Contribute to the validation of the thermal modelling of the Dewar
Validate the thermal interfaces with FPA
Provide feedback data for the design of the Active Thermal Control of the Dewar and Cooler Drive Electronics.
Validate the thermal cold interfaces (harness thermalization, thermal link)
confirm or allow to adapt the baseline concept selected after the Trade-Off analysis (e.g the number of cryogenic machines)

13. Demonstration Model
The DM, from a mechanical point of view, shall :
Validate the mechanical concept of the Dewar and FPA
Validate the interfaces between the cryostat, the cryogenic machines and the FPA
Demonstrate the thermo-mechanical and mechanical behavior of the Dewar + FPA under mechanical environment
Assess the effect of the micro-vibration (identification of the source and transfer function) and identify potential reduction solution to keep these effects below the acceptable level (CDE micro-vibration reduction algorithm, bumpers…)

14. Demonstration Model
The DM, for an electrical and radiometric point of view, shall :
validate the coupling of the different units of the detection chain with representative electrical interfaces (including cryoflex interfaces and grounding concept)
Assess the radiometric performances
Establish the auto compatibility of the detection chain with the cryogenic chain hardware
Demonstrate the behavior of the detection chain w.r.t the EMC tests (CE/CS & RE/RS) + radiation effects (TBC)

15. Demonstration Model
The DM shall also be a significant validation step for :
AIT procedures
Cleanliness issue
Contamination assessment
GSE and tests facility (including X ray sources)

16. Demonstration Model
The tests to be performed on the DM :
Performances tests (thermal, radiometric and micro-vibration)
EMC tests (CE/CS & RE/RS)
Radiation tests : TBC
Mechanical environment test
Before the final integration of the various elements of the DM at instrument level, an intermediate integration step shall be planned in order to assess the suitability of the subsystem for the follow-on tests (commissioning) and avoid in that way “debugging” at instrument level.

17. Demonstration Model
Some major documents have to be issued during the development phase of the DM :
DM preliminary requirements (at the beginning of phase A activities):
Objectives of the DM,
WBS,
Tests to be run,
Performances requirements based on the traceability matrix from Mission Requirement document,
Environmental Specification (Thermal, Mechanical and EMC) when available
Interface Control Document
 V0 to be issued mid 2015
DM Definition document and dedicated ICD
Verification plan
AIT Plan/Cleanliness plan
GSE Specifications

18. Demonstration Model
The DM consists of the assembly of the Dewar & FPA (including AC sensor) & Warm Electronic (including Anti Co electronics and PSU dedicated parts),
Not considered as mandatory : Filter wheel, ICU, PDU, Door
Aperture cylinder and optical filters to be confirmed
Event Processor algorithms assumed to be on a test bench allowing instrument DRE DEMUX output data to be acquired, archived and retrieved for on line and post processing purposes.
DM Command and Control software assumed to be implemented on a test bench

19. DM AIT Preliminary planning
The different elements of the DM are assumed to be available mid 2017 for integration at DM level
The AIT of the DM including performances tests (Thermal and radiometric) : mid 2017  mid 2018
EMC tests : 1/7/2018  1/10/18
Mechanical tests : 1/10/18  31/12/18

20. DM detection Chain
Preliminary Proposal from SRON presented end of 2014 to be further discussed : two steps proposed for the DM with enhanced HW & performances from step1 to step 2.
The preliminary configuration for the FPA DM shall comply with the objective to validate the I/F with the DEWAR and the performances within the Dewar environment (Radiometric, auto-compatibility & EMC Tests) :
The TES Sensor & FDM: 4*40 pixels as a minimum, pixels sizes TBD
The Cryo AC : 2 pixels + cryo AC CFEE
Readout electronics implementation: representative of the “baseline concept”
Thermal suspension : representative of the “baseline concept”
EMC shielding : representative of the “baseline concept”
 Dedicated meeting with SRON and INAF to finalize the DM preliminary definition.
WFEE & PSU : 2 channels and power supply and EMC filters for 4*40 pixels
CryoAC BEE
DRE DEMUX : 4*40 channels
EP : Dedicated Test bench

21. DM Way Forward
The potential Trade-off for the subsystem concept have to be identified early in the phase A activity at instrument and subsystem levels (such as cryogenic chain trade-off). The planning of these trade-off will be established in order to define the baseline concept to be selected for the DM.
If the trade-off completion does not allow to meet the delivery date of the subsystem HW at instrument DM, the impact on the interfaces, performances will be identified in order to evaluate for the instrument the potential development risk. In such cases, additional technological subsystem shall be implemented in order to cover the TRL 5/6 not demonstrated with instrument DM
At KP#2, the baseline configuration for the DM will be confirmed with the development planning.