1TIPS May 17, 2007

WFC3Ambient Calibration #2 Results

H. Bushouse

2TIPS May 17, 2007

Ambient Cal #2 Overview

• WFC3 ambient calibration #2 ran from April 13-19, 2007– WFC3 in the GSFC SSDIF clean room

– Latched into Radial Instrument Alignment Fixture (RIAF) and “CASTLE” optical stimulus

– UVIS channel operations only (IR can’t be cooled sufficiently in ambient)

– UVIS-2 detector with CCD’s at -54 C (vs. -83 C flight temp)

• Goals:– Verify re-integrated instrument operations

– Verify successful lien closures

– First look at UVIS-2 in (nearly) flight-like conditions

– Verify operations of ground support equipment to be used in thermal-vac #2

– Train and verify operations of support personnel

3TIPS May 17, 2007

Instrument Preparations forAmbient Cal #2

WFC3 closeout just prior to top cover installation WFC3 top cover installed

WFC3 lift from Low Level Positioner (LLP) WFC3 inserted into Radial Instrument Alignment Fixture (RIAF)

4TIPS May 17, 2007

Accomplishments

• ~30 SMSs, ~110 hours, 1525 images– Optical stimulus verification

– UVIS-2 detector alignment check

– System throughput with UVIS-2

– Filter ghost check (lien related)

– CCD electronic crosstalk check (lien related)

– UVIS grism calibration: throughput, dispersion, and flat fields

– Internal Calibration Subsystem check (lien related)

– UVIS-2 bias, dark, readnoise, gain measurements

– UV flats signal level check

– Encircled energy check

– CCD charge injection test

– First test of CCD Extended Pixel Edge Response (EPER) mode

• Excellent job by I&T, Ops, CASTLE & Sci Cal teams

5TIPS May 17, 2007

Thanks are due …

• IS’s

– S. Baggett, T. Brown, H. Bushouse, G. Hartig, A. Martel, L. Petro, M. Robberto

• DA’s

– E. Barker, M. Cracraft, B. Hilbert, S. Holfeltz, D. Karakla, J. Kim, K. Lindsay, D. Long, R. Lucas, J. Mack, H. McLaughlin, C. Pavlovsky, B. Shaw, E. Smith, M. Sosey

6TIPS May 17, 2007

Instrument Science Reports

• ISR 2007-15: WFC3 Ambient-2 Testing: UVIS Readnoise S. Baggett 11 May 2007

• ISR 2007-14: WFC3 Ambient-2 Testing: Calibration Subsystem Performance S. Baggett 7 May 2007

• ISR 2007-13: UVIS CCD EPER CTE measurements M. Robberto 30 Apr 2007

• ISR 2007-11: WFC3 Ambient-2 Testing: UVIS Gain Results S. Baggett 27 Apr 2007

• ISR 2007-10: WFC3 Ambient Testing: UVIS Dark Current Rate B. Hilbert 26 Apr 2007

• ISR 2007-09: UVIS Channel Filter Ghosts after Filter Replacement T. Brown 26 Apr 2007

• ISR 2007-08: Searching for Scattered Light on the WFC3 UVIS-2 Detector T. Brown 24 Apr 2007

• ISR 2007-07: WFC3 System Throughput on the UVIS Build 2 Detector T. Brown 19 Apr 2007

7TIPS May 17, 2007

System Throughput with UVIS-2

• UVIS-2 QE better than predicted• Response of both CCDs comparable to UVIS-1 chip 1• UVIS-2 curves subject to small revision at proper operating temp• Optics throughput appears to have held up well since 2004 TV#1

From STScI Instrument Science Report WFC3-2007-07 (Tom Brown)

8TIPS May 17, 2007

UVIS Detector Throughput Comparison

• UVIS-1 wins in blue; UVIS-2 wins in red• F225W only important filter for which response differs by >10%

0.6

0.8

1

1.2

1.4

1.6

1.8

200 300 400 500 600 700 800 900 1000

Wavelength (nm)

(UV

IS-1

QE

) / (

UV

IS-2

QE

)

Ratio of Higher QE CCDs Ratio of Average QEs

9TIPS May 17, 2007

Excellent Read Noise w/ UVIS-2

• Like UVIS-1, UVIS-2 demonstrates “goal” level read noise of 3 e- rms, vs. spec of 4; very important in UV

Gain = 1 e-/DN UVIS-2 (ambient) UVIS-1 (ambient)

Amp A 2.95 3.02

Amp B 2.94 2.97

Amp C 2.81 2.86

Amp D 2.90 2.99

Gain = 1.5 e-/DN

Amp A 3.35 3.21

Amp B 3.34 3.25

Amp C 3.26 3.23

Amp D 3.53 3.28

S. Baggett

10TIPS May 17, 2007

UVIS Crosstalk Satisfactorily Resolved

• Extended source crosstalk (which could result from very low level signals) is now undetectable (<0.1 e-)– Combination of hardware change and timing pattern change

– New timing patterns show slightly improved read noise as well (had been concerned they might have higher noise)

• No crosstalk in 2-amp readouts (i.e. from CCD to CCD)

• In 4-amp readout, small level of crosstalk remains from saturated sources only– New timing patterns slightly improve that level as well

– What remains is not a significant issue

preliminary analysis by S. Baggett

11TIPS May 17, 2007

UVIS Crosstalk Satisfactorily Resolved (2)

Performance w/Hardware Rev & New CCD Timing PatternsOriginal Problem

window-CCD ghost filter-CCD ghost

source

stimulus artifacts

crosstalk

12TIPS May 17, 2007

Internal Cal Subsystem Illumination Improved

• Severe glints reduced; see F390M flats below• Count rate specs achieved• As shown previously w/UVIS-1, Deuterium flats much improved in

uniformity (2× vs. 5-10×)

F390M (inverse) flat before F390M flat now

13TIPS May 17, 2007

UVIS Grism Throughput Measured

H. Bushouse

UVIS grism is WF/PC-1 spare; very little surviving data

Data provided to SOC for ERS planning

14TIPS May 17, 2007

CCD Charge Injection Working Properly

Mean charge injection signal level ~16,000 e-/pix

Noise in a single column ~15 e- rms

Much greater CTE benefit than from a lamp pre-flash of equivalent noise level

15TIPS May 17, 2007

Improved Filter Ghost Performance Confirmed

• Ambient cal measurements confirm the improved ghost performance of the filters replaced in the SOFA

• Biggest success stories: F225W (<0.4% vs. 15%), F606W (elimination of point-like ghosts), F280N (0.6% vs. 10-50% in ghost and horrific scattered light flares)

Old F225W

New F225W

16TIPS May 17, 2007

UVIS-2 Detector Alignment

• UVIS-2 aligned at Ball on 30 Jan ’07– used new, direct, “through the window” alignment transfer from

UVIS-1 to UVIS-2

• UVIS-2 within tolerance in 4 degrees of freedom, out in 2

• Additional adjustment of tip/tilt is desirable, if misalignment is confirmed in upcoming TV#2 testing

QX (

o) 0.332 ±0.20

QY (

o) -0.397 ±0.20

QZ (

o) -0.032 ±0.500

X (mm) 0.251 ±0.300Y (mm) 0.032 ±0.300

Z (mm) 0.276 ±0.850

Apr '07 (Post-align) Tolerance

UVIS-2 Alignment Summary

17TIPS May 17, 2007

UVIS-2 Misalignment Consequences

• At best focus, the performance degradation due to the current level of tip/tilt misalignment is negligible, however …

• OTA breathing exacerbates the misalignment, causing a small loss of performance over field, especially at short wavelengths– Slight EE loss in small apertures

– PSF change (due to field dependent astigmatism inherent in optical design)

18TIPS May 17, 2007

What’s Next?

• IR-1 detector package installation– Received at GSFC yesterday (5/16); installation today

• System Level Thermal-Vac #2– WFC3, with UVIS-2 and IR-1, into SES chamber ~5/29

– Ambient system functionals and alignment check ~6/1-6/5

– Vacuum testing for following ~75 days• 24/7 support from STScI IS’s, DA’s, and Ops

– Proto-flight qualification of instrument• Thermal cycling

• Performance of all thermal systems

• Full science calibration of UVIS and IR channels

• CEI specifications verification

19TIPS May 17, 2007

IR FPA QEs

0

10

20

30

40

50

60

70

80

90

100

200 400 600 800 1000 1200 1400 1600 1800

Wavelength (nm)

Qu

antu

m E

ffic

ien

cy (

%)

FPA 64 FPA 129 FPA 150 FPA 160

IR2

IR1

IR3

IR Channel Wavelength Range

20TIPS May 17, 2007

Backup slides

21TIPS May 17, 2007

UVIS-2 Misalignment EE Penalty

Optimal

As-is

OTA SMdespace: +3 Nom -3

Detectoralignment:

Optimal

As-is

22TIPS May 17, 2007

PSF Change with OTA Breathing

-3 0 +3

UVIS-2 CASTLE 633nm UV-11

23TIPS May 17, 2007

FPA 160 Dark Current

0

10

20

30

40

50

60

70

80

90

100

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1Dark Current (e-/sec/pix)

% o

f P

ixe

ls A

bo

ve

Da

rk R

ate

FPA 64 FPA 129 FPA 150 FPA 160

24TIPS May 17, 2007

FPA 160 Persistence

25TIPS May 17, 2007

FPA 160 Read Noise

CDS Noise (e- rms)

FPA 64 (IR2) 24

FPA 129 (IR1) 22

FPA 150 (IR3) 24

FPA 160 25

FPA 165 24

26TIPS May 17, 2007

FPA 165 QE

27TIPS May 17, 2007

SMGT preparations

• Revised SMGT Part 2 SMS– Added UVIS Anneal exposures

– Revised management of tungsten & D2 lamps

– Corrected UVIS quad filter commanding

– Duration of SMS is 20.5 hours

• Delivered SMS 3/30/2007 for test– SMS ran successfully in VSTIF 4/23/2007

– Science data ftp’ed to STScI for OPUS processing

• Revised SOGS Support Schedules for SM4 Functional Test– Science data from Early VEST test ftp’ed to STScI for OPUS processing

• Prepared OPUS for processing of VSTIF and Early VEST data– Anomalies identified from February VSTIF run corrected

– Software testing and delivery complete by 5/2/2007

28TIPS May 17, 2007

SMGT Part 2 SMS Content

Visit Content/ purpose Config. Dur. [hr]

01 Recovery from SAFE mode. SC 0.11 02 CR-SPLIT 0 - 7, various apertures, filters. UVIS 5.13 03 1-hr exposure, Take Data Flag dropped. UVIS 1.13 05 CTE; DARK and Tungsten targets. UVIS 0.39 06 User & predefined sub-aperture; Selected amplifiers. UVIS 0.41 04 On-chip binning; Amplifier gain; Occulted target. UVIS 0.61 07 Selected amplifiers. UVIS 0.15 08 Deuterium lamp, high current. UVIS 0.07 09 Predefined dither patterns. UVIS 0.75 10 User sub-aperture. UVIS 0.13 11 Deuterium lamp, low and medium current. UVIS 0.05 12 Quad filters. UVIS 0.25 13 Quad filters. UVIS 0.23 14 CCD charge injection. UVIS 0.70 15 Deuterium lamp, low current. UVIS 0.05 16 UVIS optics alignment and focus. UVIS 0.79 17 Anneal. SC 0.04 18 Anneal with TEC disabled. SC 0.01 19 Bias exposure. UVIS 0.13 20 Tr ansition UVIS to IR. Tungsten lamp. RAPID . IR 1.18 27 Tr ansition IR t o UVIS. Dark target. UVIS 0.14 24 STEP200, STEP400, STEP600. Occulted target. Grating. IR 0.43 21 SPARS10. Various apertures. Dither patterns. IR 0.54 22 SPARS25, SPARS50, SPARS100. Sub-arrays.

Predefined dither patterns. IR 0.29

23 SPARS200, STEP25, STEP50, STEP100. Sub-array. IR 0.20 25 MIF 900, MIF1200, MIF 1500. IR 0.19 26 IR o ptics alignment and focus. IR 0.81 28 SMOV special commanding for memory dump. SC 0.08

29TIPS May 17, 2007

Preparation ofSMGT Part 2 SMS

Anomaly Subsystem Assignee Status

Update UVIS & IR filters (F588NF200LP & F098WF140W)

APT, IM ESS Closed

Errors in SIAF aperture specifications TRANS OBS/TEL Closed

Incorrect reporting: errors for NICMOS; CR-SPLIT exp.

APT OED Closed

ANNEAL not used N/A INS/WFC3 Closed

Detector temperature set-points raised for ambient

IM OED Closed

Mosaic dithers generate pointing warnings APT OED Closed

Tungsten lamp on during readouts TRANS INS/WFC3 Closed

Patch SMS for CS 3.0 D limits IM OED Closed

Error inhibiting 6-stage TEC for ambient tests IM OED Closed

30TIPS May 17, 2007

SMGT VSTIF Results

Anomaly Subsystem Assignee Status

UVIS full-frame exposures fail in Generic Conversion OPUS/GC DPT Closed

Errors in IR dark reference file keyword values CDBS INS/WFC3 Closed

Incorrect IR dark reference file selection for subarrays CDBS INS/WFC3 Closed

IR subarray format not listed in science image headers KWDB DPT Closed

Incorrect WFC3 SIAF values SIAF OBS/TEL Closed

Incorrect CCD amp selection for UVIS Quad filters Commanding SCSB Closed

Inadequate representation of UVIS Quad filters in use OPUS/GC INS/WFC3 Open

Generic Conversion still using old IR readout times OPUS/GC DPT Closed

Incorrect PRIMESI keyword values OPUS/GC DPT Closed

Incorrect PHOTMODE keyword values CALWF3 INS/WFC3 Closed

CALWF3 IR dark frame selection enhancement CALWF3 INS/WFC3 Closed

Updated IR dark calibration reference files needed CDBS INS/WFC3 Closed