TIPS/JIM
August 20, 2009
Agenda:
INS News (Jerry Kriss)
ACS Status (Norman Grogin)
COS Status (Tony Keyes)
WFC3 Status (Susana Deustua)
Next TIPS/JIM: September 17, 2009
ACS Status Update
Norman Grogin (TIPS/JIM 20 Aug 2009)
Outline
•
WFC Post-SM4 Performance Recap
•
Day 174 Suspend : Determinations and Corrective Actions
•
Spotlight : WFC Bias Striping (Characterization & Mitigation)
•
Review of Latest SMOV Findings
TIPS/JIM 20 Aug 2009
1
WFC Performance Metrics
January 2007
(measured)
May 2009*
(projected)
Problematic*
Read noise
(e-; gain = 2)
C&S: 5.5
DSI: 4.0
> 10
DSI: 3.9-4.7
C&S: 4.4-5.7
Dark current (e-/pix/hr)
10.7
15
> 100
20-25
Hot pixels (%)
0.68
1.1
> 1.5
1.1
Full well depth (e-)
84,000
84,000
< 40,000
~80,000
Non-linearity (%)
< 0.1
< 0.1
> 0.5
< 0.2
Metric
Post SM4
(measured)
(exp time > 2 s)
CTE (@ 1620 e-)
0.999949
0.999921
< 0.9999
0.99989
Cross-talk
4x10-5
4x10-5
> 4x10-4
1x10-4
Bias shift** (%)
0.02
< 0.1
> 0.2
0.02-0.30
(before correction)
* Projected and problematic values from Gilliland et al. 2008 (TIR ACS 2008-04) .
**Residual bias shift after analytical correction of signal-dependent effect.
TIPS/JIM 20 Aug 2009
2
Day 174 Suspend: Revisited
•
ACS suspended on 23 June as result of 2 Error Status Buffer messages:
 ACS 955: CEB Command Max Retries Exceeded
 ACS 1002: NED ASIC Not Alive
•
Status at time of suspend:
 No observations executing or lost
 All monitored currents and voltages normal
 ASIC & FPGA properly initialized & functioning after SMS 173 reboot
 Error occurred during NED collection cycle (CS to ASIC comm broken)
 HST orbital position far from SAA
•
Tiger Team formed on 24 June and identified 2 possible causes:
 ASIC Status Line raised (informs FPGA of bit anomaly or comm error)
 FPGA reset in response to SEU of power regulator
TIPS/JIM 20 Aug 2009
3
FPGA/ASIC Relationship
TIPS/JIM 20 Aug 2009
4
Day 174 Suspend: Back-story
Initial assessment (presented by D. Golimowski at 16 Jul 2009 TIPS):
•
ASIC Status Line scenario not favored because it produces only ACS 955
ESB message, does not explain ACS 1002 (“ASIC Not Alive”) failure
•
Radiation test reports now available show ambient heavy-ion flux sufficient
to upset power regulator once every ~100 days
 SEU causes small voltage drop that triggers Power On Clear circuit
 FPGA and ASIC both reset; only FPGA reboots
 Scenario explains both ACS 955 and ACS 1002 ESB messages
Plausible, but this outcome of has 0.1% probability after ion hit because it
occurs in small (2 ms) window of 2 s NED collection cycle.
TIPS/JIM 20 Aug 2009
5
Day 174 Suspend: Resolution
Revised assessment (subsequent to TIPS presentation on 16 Jul 2009):
•
Further investigation of FSW and ESTIF testing revealed scenario in which
raised Status Line produces both 955 and 1002 error messages with
reasonable probabilities.
•
GSFC subsequently discovered that cause of raised Status Line was singlebit comm error, which is automatically corrected by hardware. Status Line
supposed to be raised only for double-bit comm errors. Incorrectly set bit in
error response register → register now patched
•
MO and Project considering proposal to alter FAC and FSW to allow “slow
suspend” of ACS after future occurrences of 955 errors to enable dumps of
FPGA and ASIC memory before power shutdown.
Estimated delivery time: 2.5 months.
TIPS/JIM 20 Aug 2009
6
WFC Bias “Striping”
•
•
•
•
Bias striping pattern varies between WFC chips and between frames
1/f noise (1mHz to 1Hz) generated with ASIC during bias voltage offsetting
Striping appears constant across rows of CCD : ~removable in S/W
No measurable effect on ~bright-src photometry, but could be worrisome for
studies at low surface brightness (and low background)
TIPS/JIM 20 Aug 2009
7
De-striping the BIAS: Before/After
ACS/WFC Bias Image: before correction
TIPS/JIM 20 Aug 2009
ACS/WFC Bias Image: after correction
8
Superbias Quality
•
•
•
•
Striping averages away at nearly N1/2
Stripe-mitigated superbias only marginally noisier
than pre-failure superbias
Superdark similarly amenable to stacking
Testing underway for end-user app to de-stripe
science images (similar to the WFPC2 wdestreak)
TIPS/JIM 20 Aug 2009
9
ACS News Roundup
• WFC crosstalk (A. Suchkov):
– Pre-failure: Avg. ghosting on victim amps is ~1-2 e-/pix.
– Post-repair: Visually indistinct but still present for high fluxes
• WFC DARK & BIAS monitoring (T. Desjardins, P.-L. Lim):
– Now “warm” pixels = 0.04 ≤ DC < 0.08 e-/s; +40 hot&warm pix/day
– Bias level drifting ~linearly at 0.02 e-/day
• SIAF (C. Cox): New aperture definitions installed.
• Pixel area map (A. Fruchter):
– Two new header keywords for Multidrizzle (no end-user impact).
• Pipeline calib. files (R. Bohlin, C. Cox, T. Desjardins, R.
Lucas, J. Mack, A. Maybhate, M. Mutchler, et al.)
– WFC Flatfields, Gain ratios coming soon (old Flatfields are ~same)
– Plan is for all calib. files to be in place for post-ERO operations
TIPS/JIM 20 Aug 2009
10
Summary
•
All SBC and WFC SMOV programs have been executed and data analysis is
nearly complete. No significant post-SM4 performance issues discovered.
•
Day 174 Suspend traced to FAC bug, now patched. Update to FAC/FSW
planned to implement “slow suspend” for memory dumps before shutdown.
•
Low-level bias striping in WFC is being characterized & mitigation strategies
being tested. “Clean” superbias/superdark will be in pipeline as of 9 Sep 09.
•
Both SBC and WFC have had successful and spectacular “first light”
external observations. (Pretty pictures still embargoed -- sorry!)
 ACS now proceeding with WFC and SBC GO Science
 Farewell to Tyler Desjardins (RIA in AWT), departing STScI for
grad school. You will be sorely missed!
TIPS/JIM 20 Aug 2009
11
TIPS/JIM
August 20, 2009
Agenda:
INS News (Jerry Kriss)
ACS Status (Norman Grogin)
COS Status (Tony Keyes)
WFC3 Status (Susana Deustua)
Next TIPS/JIM: September 17, 2009
TIPS
COS Status: SMOV update II
STScI/CU COS Team
20 August 2009
COS Highlights
 NUV Optical Alignment verified post-move of HST secondary
 FUV focus not yet optimal; requires additional sweep
 NUV Sensitivity
–
Primary PSA data obtained for all gratings, in analysis
 NUV Internal Flat Fields
–
Data obtained, analysis ongoing; no reference file update anticipated
 NUV/FUV Internal/External Wavecals
–
All observations completed; spectrum templates and dispersion relations
in preparation
COS Highlights (continued)
 FUV Sensitivity
–
Primary PSA data being obtained this week for all gratings
 FUV/NUV Dispersed Light Target Acquisition
–
–
–
All PSA visits completed
NUV Imaging verification in progress
All TA modes working well; small additional updates expected
COS Upcoming Events
 FUV Focus Re-check
–




Mon 24 August
FUV/NUV High S/N Verification
FUV/NUV Structural / Thermal Stability
FUV/NUV Spectroscopic Performance
FUV External Flat Fields
 BOA Calibrations
–
Imaging performance, TA verifications, sensitivity, spectroscopic
performance
COS SMOV4 NUV Sequence
HST release
COS-01
Recovery from
SAFE
COS-06 11467
NUV Internal
Functionality &
Operation
Internal pressure
<20 micro-Torr
MAMA LV on
COS-02 11353
Onboard
Memory Check
COS-03 11354
Science Data
Buffer Check
COS-04 11355
NUV Initial HV
Turn-on/Ramp-up
COS-07 11355 v5
NUV
Fold Test
COS-05 11466
NUV
Dark Measure
24h
data
24h
data
SCI
REF
COS-08 11468
OTA to FGS
Alignment (NUV)
Wavelength
Ranges OK
SIAF update
available
Uplink
24h
data
Alignment
Not OK
COS-10 11496
Internal NUV
Wavelength Meas
& Grating Eff.
Vis 1, 3 – lamp 2
COS-09 11469
NUV Optical
Alignment /Focus
visit 1-6
24h
data
COS-17 11477
NUV Ext.
Spectr. Perf.
Part 2
Enable Wavecaldependent
NUV Calibration
COS-15 11475 Wavelength
Internal NUV
Ranges
Wavelength
Not OK
Verify
24h
data
REF
Require
Wavelength
Scale Update
COS-16 11476
NUV Ext.
Spectr. Perf.
Part 1
Internal pressure
<10 micro-Torr
BEA Complete
ERO
FUV SMOV
sequence
24h
data
Uplink
COS-19 11479 v2-n
NUV Spectr.
Sensitivity
REF
COS-20 11480
NUV Structural
& Thermal
Stability
COS-21 11481
NUV High S/N
Verification
REF
COS-14 11474
NUV Int/External
Wavelength Scales
Uplink
IHB
24h
data
COS-09 11469
NUV Optical
Alignment vis 7-12
External
Observations
24h
data
COS-19 11479 v1
NUV Spectr.
Sensitivity Quick
Uplink
24h
data
COS-10 11470
Internal NUV
Wavelength
Meas
May require wait
9 April 2009
SIAF update
start
Alignment OK
Uplink
Uplink
COS-11 11471
NUV Imaging
Acq Verify
REF
COS-12 11472
NUV Dispersed
Acq Verify
Uplink
REF
COS-18 11478
NUV
Flat Fields
COS-13 11473
NUV Imaging
Performance
Do NOT
Require
Wavelength
Scale Update
COS SMOV4 FUV Sequence
Outgassing
Concern?
XDL at OPER
Internal
Pressure
COS-01
HST COS-02 11353
release COS-03 11354
<100 microTorr
NUV SMOV
sequence
COS-08 11468
NUV Optical
Alignment /Focus
Uplink
SIAF update
start
May require wait
COS-31 11489
FUV Ext.
Spectr. Perf.
Part 1
Wavelength
Ranges OK
REF
COS-27 11496
Internal FUV
Wavelength Meas
Vis 2 – lamp 2
SIAF update
available
COS-30 11488 Wavelength
Ranges
Internal NUV
Not OK
Wavelength
Verify
24h
data
Uplink
Uplink
24h
data
COS-26 11484
FUV Optical
Alignment /Focus
visit 1-4
COS-27 11485
Internal FUV
Wavelength
Meas – Vis 1
COS-26 11484
FUV Optical
Alignment /Focus
Verif. – visit 5-6
Alignment OK
COS-36 11494
FUV High S/N
Verification
Require
Wavelength
Scale Update
24h
data
COS-28 11486
FUV Dispersed
Acq Verify
Does NOT Require
Wavelength Scale
Update
Enable
FUV ERO
No
wavecal
COS-32 11490
FUV Ext.
Spectr. Perf.
Part 2
COS-26
11484
Enable
WavecalFUV
Focus
dependent
FUVre-check
Calibration
visit 93-95
REF
COS-29 11487
FUV Int/External
Wavelength Scales
24h
data
Uplink
External
Observations
COS-23 11356
FUV Initial HV
Turn-on/Ramp-up
Pressure Gauge OFF
COS-25 11483
FUV Internal
Functionality &
Operation
COS-34 11492 v1
FUV Spectr.
Sensitivity - Quick
24h
data
Internal
Pressure
<10 microTorr
BEA Complete
uplink
24h
data
COS-09 11469
NUV Optical
Alignment /Focus
COS-22
FUV Detector
Door Open
COS-24 11482
FUV
Dark Measure
24h
data
24h
data
COS-33 11491
FUV
Flat Fields
REF
COS-34 11492 v2-4
FUV Spectr.
Sensitivity
REF
COS-35 11493
FUV Structural
& Thermal
Stability
24h
data
Rapid data turnaround required
ERO
Required to enable ERO
SCI
Required to enable science
REF
Analysis produces reference file
IHB
Results reported in IHB
9 April 2009
Optical Alignmnet / Focus Status
• NUV:
– All pointing and focus adjustments completed
nominally; excellent focus achieved; final verification
after HST secondary mirrror move
• FUV:
– Initital spectrum resolution analysis suggests that we are not at
optimal focus of the FUV channel
– Will perform (next week) an additional focus sweep for G130M
and G160M using a brighter target with narrower lines
7
NUV Optical Alignment Final Focus Verification Sweep
8
NUV Sensitivity - Preliminary Results
• Data for the first three visits, using GRW+70D5824 and
GD71 have allowed us to derive (preliminary) independent
sensitivity curves for each grating and stripe.
• Second order contribution to G230L still under study.
9
NUV Sensitivity (11479) --- Preliminary Results
Red – Stripe A; Black – Stripe B; Blue – Stripe C
10
FUV Sensitivity - Preliminary Results
• Data from first two quicklook visits, using primary standard
LDS749B have allowed us to derive (preliminary)
independent sensitivity curves for each grating and segment
– One visit at initial HV setting; one visit at lowered operational HV
– Very small relative effective area decrease at lowered HV
– No sign of the “divot and clod” at lowered HV
11
Before/After HVNOM modification
12
FUV Quicklook Sensitivity (11492) --- Preliminary Results
13
FUV Quicklook Sensitivity (11492) --- Preliminary Results
14
FUV Quicklook Sensitivity (11492) --- Preliminary Results
15
NUV Flat Fields
•
•
•
First 36 visits completed nominally
Analysis shows that on-orbit flat (300 counts/pixel) is consistent with
the ground flat (12,000 counts/pixel), so no further visits are needed
Upcoming High S/N observations will be used for verification
16
NUV Flat Ratio
17
NUV S/N Plot
18
Instrument Operational Updates
•
Updated all the G130M λcen 1291 and 1300 FP-POSs by +1 step.
– The five central wavelengths and 4 FP-POS positions for G130M were
intended to cover 20 consecutive steps of OSM1.
– Wavecal program analysis indicated that as a result of a ground
adjustment in 2008, G130M/1300 FP-POS=1 was set to the same position
as G130M/1309 FP-POS=4, so there were only 19 unique OSM1 steps.
•
•
•
•
Updated position of G285M 2695 so that wavelength ranges of stripes
A/C conform to desired values
Lowered HVNOM on FUV segment B to alleviate “divot and clod”
Zero-order light on detector on G140L 1230 FP-POS=4 setting only;
in process of determining most efficient operational change to avoid
Many target acquisition parameters updated (image and spectrum
locations; aperture offsets; plate scales – all target acquisition modes
performing very well; verification programs ongoing
19
COS FUV First-light

TIPS/JIM
August 20, 2009
Agenda:
INS News (Jerry Kriss)
ACS Status (Norman Grogin)
COS Status (Tony Keyes)
WFC3 Status (Susana Deustua)
Next TIPS/JIM: September 17, 2009
WFC3 Current Status
Susana Deustua 2009 August 20
1
WFC3 SMOV Status
•45 WFC3 SMOV Proposals
•40 are complete
•2 will be done by end of this week
•=> 92% of visits are completed as of 18 Aug 2009
•Analysis well underway
Susana Deustua 2009 August 20
2
Some WFC3 Preliminary Results
•
•
•
Focus and Alignment
– completed
– EE nominal
Geometric Distortion – UVIS is good to 2 milli arcsec
– IR not as precise, but still good.
– Updated IDCTAB is being tested,
release to GOs soon.
Dark Current, Readnoise
– UVIS:
• readnoise ~3 e– IR:
• readnoise ~14 e-
Susana Deustua 2009 August 20
3
Some WFC3 Preliminary Results:
“bowtie”
Quantum Efficiency
Hysteresis (QEH) observed
during TV3
-Change in QE of CCDs with
time
-Mitigate by “flash”/Pin
detector
-Pre- and post- “pinning”
internal flats ratios are
plotted
-. Most points fall between
+/- 0.5%.
Susana Deustua 2009 August 20
4
Some WFC3 Preliminary Results
•
Photometry compared to ETC predictions
– UVIS throughput is 10-20% higher
– IR throughput is 5-15% higher
– ETC and SYNPHOT will be updated shortly.
1
1.04
1
Susana Deustua 2009 August 20
5
Some WFC3 Preliminary Results
Susana Deustua 2009 August 20
6
WFC3 Preliminary Results: Jupiter
•
•
•
•
•
QUAD-SUB and UVIS1-2K4-SUBs performed nominally
Proper amp and quadrant were read for each exposure
Petro pre-verified pointing from spacecraft command files “hit the target”
Distortion was corrected by drizzling using Zemax optical
model (Bushouse)
Fringing results
– FQ924N Raw fringe amplitude ~14%
– FQ924N FLT fringe amplitude ~3.5%
Susana Deustua 2009 August 20
7
WFC3 Science
•
•
•
•
WFC3 ERO observations completed
WFC3 ERS observation scheduled
Cycle 17 Science enabled
Cycle 17 Calibrations started
Bottom Line: WFC3 working nominally
Susana Deustua 2009 August 20
8