Transcript No Slide Title - CPPM

Integral Field Spectrograph
Anne EALET
CNRS (IN2P3) FRANCE,
Instrument Scientist
Eric PRIETO
CNRS,INSU,France,Project Manager
11 November 2003
Spectrograph: Background
magnitude
SNAP
imager
ID Ia
spectro
M , L
•A contribution supported by CNRS (IN2P3 &
INSU) and the French space agency (CNES)
•No exchange funding, non US cost
See overview in S.Perlmutter/M.Levi talks
2
Spectrograph: Overview
• Spectrograph studies
• Science driver
• Requirements for the Spectrograph
• Spectrograph concept and Status
• Risk analysis
• R&D French activities:
• Slicer prototype
• Detector and electronics
•
R&D plan
• Summary
3
Specifications
• A spectrograph dedicated for SN physics
—Identification of SNIa Si 6150 A line up to z=1.7 (range)
—Precision on physical parameters to correct magnitude (resolution) and
derive systematics for evolution
— can measure the host galaxy redshift when possible
—Precise calibration (sampling)
4
Requirements
An instrument minimizing exposure time for
faint SN
Wavelength range [0.35-1.7] mm
Spatial resolution 0.15”
Low spectral resolution (~100)
Under sampled in the NIR to minimize the noise (+dithering to
recover)
• Two arms to increase performance
to improve UV part of the faint SN
•
•
•
•
• Highest throughput by reflective
optic only (mainly limitated by
detector QE)
+
5
Spectrograph characteristics
Property
Visible
IR
Wavelength coverage (mm)
0.35-0.98
0.98-1.70
Field of view
3.0" / 6.0"
3.0" / 6.0"
70-200
70-100
0.15
0.15
LBL CCD
10 mm
HgCdTe
18 mm
>40%
>40%
Spectral resolution, l/dl
Spatial resolution element (arc sec)
detectors
Efficiency with OTA and QE
6
Spectrograph concept
7
Spectrograph: Design constraints
REQUIREMENTS for space:
INTEGRAL FIELD TECHNOLOGY:
•Compactness
•Reflective optics
Trade-off
reconstruct a DATA CUBE 3D (x,y,l)
image of the sky
•No accurate slit positioning
use a technique to rearrange the 2D (x,y)
•All information in one exposure
in a 1D equivalent long slit => sliced the
field
• High throughput
Y(slice)
•3D spectroscopy for galaxy +SN
l
l
X (pixel)
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CONCEPT
3D spectroscopy with integral field technology:
• Integral Field using the new generation of Image Slicer
• Disperser=Prism for low and “constant” resolution
• 2 detectors (CCD, HgCdTe)
• Dichroic for beam separation
All spectral and spatial
information in one
exposure
Fulfills all requirements
for science and space
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Spectrograph: Functional Overview
Shutter
Slicer
Unit
Relay
Optics
Calibration
lamps
Collimator
Dithering
Science
Software
Thermal
control
Operation
Prisms
Dichroics
VIS
CAM
NIR
CAM
Visible
Focal
plane
NIR
Focal
plane
Interface
Electronics
10
Spectrograph design status
11
Instrument design road map
Primary SNAP specifications
First requirements
2002
Define system
Concept definition
requirements
Pre conceptual
design
2003
R&D
Prove the
feasibility
SLICER AND
Detailed simulation
Interface control
document
New requirements
DETECTORS/
ELECTRONIC
Verify performances
Budget errors
Conceptual
design
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Pre optical design
• optics with 7 mirrors
• two arms configuration
• Two prisms
IR
detector
Visible
detector
entrance
prisms
slicer
13
Spectrograph: implementation
Under the global shielding
14
Opto-mechanical concept
First studies on
•Mechanical environment
•Thermal analysis
•Modal analysis
• interface with SNAP
•
•
Dimension < 400 mm
Weight < 15 Kg
Material Invar
Kinetical mount
Global shielding + local
shielding around detector
(focal plan)
Thermal study (LBNL)
T > 100 K
Details in E.Prieto talk
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Focal plan development
Mechanical/thermal/interface studies to define a preliminary design
No ‘single point failure’
=> Detectors should to be duplicated:
two detectors and their electronic:
Field of view of 3’’X6‘’ instead of 3’’X3’’
Need 40 slices
No effect on optic
16
Spectrograph issues
Focal plane:
•Visible detector : very low noise versus cosmic ray radiation
lower integration time because of radiation => larger readout noise
alternatives:
LBL CCD issue thinner (CRIC: noise ok )
EEV CCD issue fringing
HYVISI issue dark current (same readout elec than IR)
•IR Detector : 3000s integration / cosmic rays rejection (noise
and drift)
Rational: reduce spectro allocated time of at least 2 or 3!
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Instrument simulation
Hardware
specifications
Physics
specifications
Library of PSF
Optical design
Pixels response
Optical simulation
No
Physics
simulation
Calibration
OK
Yes
Optomechanical
simulation and design
No
OK
Yes
Final performances
AND
No
OK
Yes
Construct
prototype
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Simulation status
•
•
•
A full detailed simulation of the optical design is under developement
Used to simulate SN spectrum on the whole wavelength range
Used to verify the basic performances of the instrument (resolution and
throughput)
Ne
Background
subtracted
Calibrated
Calibrated
Exemple of a spectrum
at z=1.7
Background
#pixels
•New developments are going to parameterize PSF using HERMIT polynomial decomposition
•Implementation of realistic data cube will be possible within the SNAP software
•Volume of data will be kept small with reasonable CPU time
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Calibration status
•First calibration oriented performance requirement done (doc)
•Major calibration procedures have been identified :
•flatfielding
•wavelength
•absolute spectro-photometric calibration
•Preliminary list of needs for calibration have been identified
•The strategy will be developed next year :
• Details on procedure and error budget evaluation
•Derive stability requirements and observatory
•Used as input to the operation time budget
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instrument roadmap

Scientific and technical requirement

Optics



Optical development: new design, tolerance studies

Dichroic studies and prototyping (first expertise dec 03)

Structural :Trade on the structure, choice ,opto-mechanical studies

Thermal :modal and thermo-elastic analysis
Focal Plane

Review of detectors/technologies –choice

Early focal plane development
Slicer

Slicer technology pushed to TRL 6

adaptation to SNAP

Calibration procedures studies

Software development : data processing/monitoring

Interface control requirement
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R&D: Risk analysis
risk
mitigation
activity
completion
Slicer
development
ESA/NGST prototype
30 elmts in
space
environment
TRL6 end 2003
Snap adaptation 2005
Focal plane
Detector technology trade-off
Early focal plane development
R&D on detector
and readout
electronic
Detector choice and
Concept Design 2005
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R&D activities
23
Ongoing R&D slicer
Slicer development and validation to TRL6 level
(ESA funding)
—Prototype ready at LAM
—Test on visible and IR
—First test results (see eric talk)
24
Slicer results
Impressive alignment of the pupils on the pupil mirrors within 50µm
alignment of the virtual slits on the slit mirrors within 20µm
See E.Prieto presentation
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R&D detectors/electronic
Detector validation and electronic development
(IN2P3 funding)
CCD
•Detectors:
•Test of CCD from LBNL (frame transfer, performance, QE, readout) in
progress
•Evaluation of a CCD with EEV as spare with emphasis fringing test and
efficiency. Issue on radiation : test for 2005 if funded
•Bench test ready
•Electronic:
readout evaluation using MEGACAM-like-ASIC for low noise purpose
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R&D detectors/electronic
IR
Detectors:
•MUX received
•Prototype ordering HgCdTe 1kx1k cut off at 1.7 mm for evaluation
(temperature, QE, dark, readout…) to be received Jan 04 , test result
June 04
•Bench test be ready for Jan 04
•Electronic:
readout demonstrator for IR pixels.
FPGA + microprocessor + Ethernet
Delivered june 04
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Spectrograph: R&D deliverables
Deliverable
Completion
Status
Trade & decision slicer technology-TRL5
Mar-01
done
Baseline specifications
Jul-02
done
Performance requirements
Nov-03
draft
Science and technical trade studies
Nov-03
draft
Pre-conceptual design
Nov-03
done
Interface control requirement with SNAP
Nov-03
draft
Calibration procedures studies
Dec-03
draft
Slicer prototype report –TRL6
May- 04
Review on detector/ decision
Sep-04
Detector confirmation
Dec-04
Instrument concept/ZDR
Dec-04
Focal plane development plan
Jul-05
SNAP Slicer prototype development
Jul-05
Interface control requirement with SNAP
Jul-05
Conceptual design report/review
Jan-06
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Spectrograph: R&D Manpower
Team
Activity
FTE
Associated
spectro
FY04/05
FY04/05
INSU/CNRS+
European team
Generic slicer for
space application
10
2.5
IN2P3/INSU/CNRS
+ Euro 3D
Software for 3D
spectrograph
10
2
R&D effort within the SNAP collaboration and outside the collaboration
Sharing development when possible
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R&D Manpower Spectrograph
design (in2p3/insu)
Personnel
Activity
FTE
FY04
FY05
Dr.A.Ealet
Instrument Scientist
0.8
0.8
Mr.E.Prieto
P.Manager/Optic lead
0.5
0.5
Mr C.Macaire
Slicer/optical engineering
0.5
0.5
TBC
Optical engineering
0.2
0.5
Mr.P.E.Blanc
Mecha. /thermal lead
0.5
0.5
Mr.C.Rossin
Thermal designer
0.2
0.3
Mr.P.Levacher
Electronic control engineering
0.2
0.2
Dr.A.Bonissent
Software lead
0.8
0.8
Dr.A.Tilquin
Simulation
0.5
0.5
Dr.P.Ferruit
Calibration
0.2
0.5
M.Aumeunier
PHD/simulation/optic
1.
1.
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R&D detector/electronic(in2p3)
Personnel
Activity
FTE
FY04
FY05
Dr.E.Barrelet*
Detector/Electronic lead
0.8
0.8
Dr.G.Smadja
Focal plane lead
0.5
0.5
Mr.A.Castera
Detector engineering
0.4
0.4
Mr.C.Girerd
Electronic engineering
0.5
0.5
Mr.Detournay
DAQ software
0.3
0.3
Mr.Genat*
Electronic engineering
0.5
0.5
Mr.R.Sefri*
Electronic engineering
1.
1.
Mr.Lebollo*
Electronic engineering
0.6
0.6
C.Juramy
PHD
1.
1.
D.Vincent
Mechanic
0.3
0.3
* Involved in the SNAP electronic effort see Von Der Lippe presentation
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PLANNING
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Summary
The spectrograph :
A key instrument for the SNAP mission
Instrument based on integral field technique and slicer unit
Technology R&D is well in phase with SNAP
France team will take in charge the complete instrument with
CNES/CNRS funding
Development plan to CDR
—risk assessments
—R&D activities on detectors and validation
—Slicer prototype validation to TRL6
—Develop integration & test plans
—Performance specifications & tolerance analysis
—Develop conceptual design
—Develop preliminary cost & schedule ranges
—Develop preliminary interface control specifications/documents
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