JWST OVerview

1
The JWST Detector Characterization Project in
the Independent Detector Testing
Laboratory Don Figer, STScI/JHU January 9,
2003 AAS 201 Seattle, WA
2
Detectors Are Important for JWST
3
JWST NIR Detector Requirements
4

• IDTL Role in
• JWST Detector Program

5
NIR Detector Characteristics

• Dark current
• Read noise
• Linearity
• Latent charge (persistence)
• Relative and Absolute Quantum efficiency (QE)
• Intra-pixel sensitivity
• Thermal stability
• Radiation immunity

6

• Past and present personnel

Eddie Bergeron Data Analyst
Tom Reeves Lab Technician
Robert Barkhouser Optical Engineer
Bernie Rauscher Project Scientist
Utkarsh Sharma Graduate Student
Mike Telewicz Intern
Gretchen Greene Mechanical Engineer
Steve McCandliss JHU Lead
Ernie Morse Data Analyst
Monica Rivera Intern
Scott Fels Intern
Don Figer Director
Sito Balleza Systems Engineer
Mike Regan System Scientist
Russ Pelton Technician
7
IDTL

• IDTL provides unbiased testing of detectors and
  has been operating for 2 years
• Completed Target Field Simulation Testbed project
  (18 months, 8/02 end)
• Will finish JWST Detector Characterization
  project (2 years, 3/03 end)
• In pre-proposal phase
• JDC Figer
• 3/03-6/10
• perform optimal-use testing
• develop High Volume Testing (HVT) program
• collaborate on HVT
• perform concurrence testing
• perform anamoly mitigation testing
• perform ground calibration
• TFST Sivaramakrishnan
• 24 months
• produce 'day in the life of' JWST WFSC
• determine what factors impact OPD measurement  
• provide regression test data for pipelines, WFSC
• SNAP Figer
• 18 months

8
IDTL Test System
Controller Electronics
Dewar
Entrance Window
Vacuum Hose
He Lines
9
Hawaii 1R with 5.0 mu Cutoff
10
Rockwell Raytheon 2K Devices
11
IDTL Measurements Dark Current

• Lowest measured dark current is 0.006
  e-/s/pixel.

12
IDTL Measurements Read Noise

• Read noise is 10 e- for large number of reads.
  (system read noise is 2.5 e-)

13
IDTL Measurements Gain
14
Hawaii 1R with 5 um Cutoff
15
IDTL Test System
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IDTL Measurements AQE

• QE measurements have an accuracy of 10.

17
IDTL Measurements RQE

• Relative QE maps show significant variations
  across field

18
JWST Detectors
HST/NICMOS!
80 megapixels of flight-qualified
detectors!!! (10 times all detectors on
telescopes today)