(Novembre 10, Nice)

(Novembre 10, Nice)

Science Case

Follow-up GAIA (1 milliard d’étoiles, positions et vitesses) : priority identified by:• ESO/ESA working group on «The Galaxy» (Turon et al. 2008)

• Astronet Roadmap

• identifié lors de la prospective INSU 2009

Two cases identified:

- low-resoluion spectroscopy (R~5000) for stars V>17 (3rd dim of velocities)

- high-resolution spectroscopy (R~20000) for stars V>10 (detailed chemical abundances)

Rien en Europe avant GYES; maintenant 2 projets low-R

complémentaire: HERMES/AAO pour l’hemisphère sud

(Novembre 10, Nice)

GYES science case

• Chemical labelling of galactic populations (équipe Gaia)• discs

• disc-bulge interactions

• halo

• Galactic dynamics

• Other sciences with the survey• paramètres fondamentaux des étoiles, physique stellaire

• ISM

• variable stars (N. Nardetto)

• Globular clusters (A. Recio-Blanco)

(Novembre 10, Nice)

GYES Science Team (Phase A)

P. François (PS), E. Caffau (co-PS), F. Arenou, C. Babusiaux, C. Balkowski, O. Bienaymé, P. Bonifacio, D. Briot, R. Carlberg, B. Famaey, Y. Frémat, A. Gomez, M. Haywood, V. Hill, R. Kudritzki, R. Lallement, P. de Laverny, B. Lemasle, C. Martayan, R. Monier, D. Mourard, N. Nardetto, A. Recio-Blanco, N. Robichon, A. Robin, M. Rodrigues, F. Royer, C. Soubiran, C. Turon, K. Venn, Y. Viala

(Novembre 10, Nice)

GYES project & timelinesPhase A (GEPI +Oxford) January - Sept 2010• Phase A study financed by CSA-A : Jan - Sep 2010• July 2010 - Mid-Term review (at SPIE San Diego)• 27-28 October 2010 Concept Design Review

Delta-Phase A November 2010 - March 2011

Phase B March 2011 - April 2013

PAE July 2015PAH & Comissioning July-Dec 2015FAH December 2015

Survey 2016-2020

(Novembre 10, Nice)

GYES System Team (Phase A)

P. Bonifacio (PI)

P. François (PS), E. Caffau (co-PS),

F. Royer (IS),

J.-L. Dournaux (PM),S. Mignot (SE), M. Cohen, D. Horville (optics) , J.-M. Huet (Mechanics) , I. Guinouard (fibres), G. Fasola (detectors & electronics) , P. Laporte (thermal control), G. Dalton, I. Lewis (positioner)

(Novembre 10, Nice)

(Novembre 10, Nice)

(Novembre 10, Nice)

(Novembre 10, Nice)

Structure• Gantry extent 962x911mm

• Z-axis 1332mm behind last corrector lens

• Fibres exit through tumbler axis

• Field plates have small rotation (retractors rotate with the plate), independent of each other, to account for differential refraction and intrinsic field rotation

• Focal plane imager deployed between corrector and observing field plate

• Trade-off between footprint and height

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Software simulations

Full simulation of geometry, button manufacturing tolerances.

Random target distribution

20 fibres reserved for sky allocation

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Fibres etc.

• Ensure the link between the positioner and the spectrograph•500 mono-object fibres•80 µm core•40 m long•Compatible with exchange procedure

• Perform simultaneous wavelength calibration•20 fibres•80 µm core•short (within spectrograph)

• Close guiding control loop•5 to 10 7-fibre IFUs•33 µm core•short (within PFUE)

(Novembre 10, Nice)

Bundle

• Collaboration with Polymicro (fibre) and SEDI (French company specialised in fibre cables) • Stiff structure to limit radius of curvature•FRD•breaking fibres

• Armoured cable•withstand instrument exchange

• Need for individual protection buffer not determined yet

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Transmission (I)Depending on the length and wavelength: impact on the location of the spectrograph.

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Transmission (II)

• Worst case for non-telecentricity (one button type) & alignment

• Goal for alignment and FRD

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Spectrograph

• Bench and feet (with pneumatic dampers)

• Cover (on bench or on ground)

• Mechanical mounts & optics:– collimator (3): – dichroic (1)– VPH gratings (2 x2)– cameras (2 pre-integrated)

• Slit exchange mechanism

• Detectors (2 x2)

• Dewars (2)

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Baseline and back-up design

• Backup design: single VPH disperser

→ Consolidate the backup design to eventually consider it as the new baseline design

• Baseline: double VPH disperser

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Disperser (I)• Type : VPH grating (large size and gr. density)

• Backup design specification:

• Baseline specification:

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Disperser (II)• Baseline transmission efficiency:

– Peak: 84%

– Edges: 5% - 15%

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Disperser (III)• Backup design transmission efficiency:

– Peak: close to 100%

– Edges: 40% - 47%

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Resolution

(Novembre 10, Nice)

Transmission (II)

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Transmission (III)• Estimates of SNR per pixel in 2h @ V=16• centre of slit

• only the photon noise

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GYES Survey

• Survey Strategy : 262 nights over 5 years ~ 3 ×105 stars in the disc, halo, bulge & clusters • Survey Management Plan: (~30FTE over 5 yrs)

• Input catalog & observation preparation• Spectra analysis pipeline development• Spectra analysis• Output catalog production & distribution

(Novembre 10, Nice)

(Novembre 10, Nice)

GYES project & timelinesPhase A (GEPI +Oxford) January - Sept 2010Delta-Phase A November 2010 - March 2011• Consortium build-up: + GEPI+ OCA: ICS, AIT, Optics (corrector ? tbd), Survey

Data Analysis, Science Team (PS)+ LAB: ICE, Science Team+ Oxford: positionner (hard and software)• Consolidate Management plan (+ AIT plan, +++)• Science tradeoffs (impact of new baseline design)

Phase B March 2011 - April 2013PAE July 2015PAH & Comissioning July-Dec 2015FAH December 2015

Survey 2016-2020

(Novembre 10, Nice)

GYES project & timelinesPhase A (GEPI +Oxford) January - Sept 2010

Delta-Phase A November 2010 - March 2011

Phase B March 2011 - April 2013• kickoff for Phase B march 2011• PDR May 2012• FDR April 2013

PAE July 2015PAH & Comissioning July-Dec 2015FAH December 2015

Survey 2016-2020

(Novembre 10, Nice)

GYES System Team (Phase B)P. Bonifacio (PI) P. François (Co-PI)

V. Hill (PS)

F. Royer (IS)

P. Jagourel (PM) +OCAS. Mignot (SE)M. Cohen, D. Horville + OCA (optics) J.-M. Huet (Mechanics) I. Guinouard (fibres)G. Fasola (detectors & electronics) + LAB (ICE)P. Laporte (thermal control) G. Dalton, I. Lewis (positioner)

ICS: OCA (JM Clausse)AIT : OCA (F. Henault)

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Contribution OCA

Actuel FIZEAU:ICS: 3.7 FTE

0.6 FTE en phase B; 3FTE en phase C

AIT: 4.4 FTE1 FTE en phase B; 2 personnes en phase C + salle grise

Optique (en discussion: correcteur de champ ?)FODR phasé avec PDR (ie mai 2012)

Actuel Cassiopée:Survey: ~4 FTE sur 5 ans

Spectral analysis (pipeline development & operations)

(Novembre 10, Nice)

GYES project & timelinesPhase A (GEPI +Oxford) January - Sept 2010

Delta-Phase A November 2010 - March 2011

Recommandation SAC (nov 2011) - Board (dec 2011)

Phase B March 2011 - April 2013

PAE July 2015PAH & Comissioning July-Dec 2015FAH December 2015

Survey 2016-2020

(Novembre 10, Nice)

(Novembre 10, Nice)

Status of study• Report status of study

– 9-month study

– still work in progress

– HW cost 4.6 M€ (with contigencies)

– Consolidated cost 13.8M€

– Timeline: on sky Dec 2015

• Active developments– refinements of the baseline

– need to loop back to science requirements and tradeoffs

– need for input as regards options (impact on timescale)

– need for input from CFHT (eg. guiding, software)

→ active work on transmission: many improvements possible

active reaction to VPH issue

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TypeOnly the fibres from Polymicro have been investigated (commonly used in astronomy).

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For Phase B some noveltiesP. Bonifacio (PI) P. François (co-PI)

V. Hill (PS)

F. Royer (IS)

P. Jagourel (PM)

+ Participation of OCA (ICS + AIT)

LAB (ICE+ Detectors)

+ ????