WFC3 Thermal Vac. 2004
WFC3 Detector Performance
from the Thermal Vac tests
(M. Robberto, ESA-STScI)
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
1
CCD layout
Amp A
Amp B
CCD43-178
CCD43-18
Amp C
December 16, 2004
Amp D
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
2
UVIS Dark current
CEI SPECs
- Dark current <20 e/pix/hour @ -83 C
- Bias stability in single row repeatable to <2 e rms, correctable to <1 e rms
DCL results for CCD43-178
DCL test conditions: 2hr darks,
frames overscan and bias subtracted.
Results from gaussian fit to the histogram.
DCL results for CCD43-178 dark current data are anomalous
Temp Channel
-70
A
-70
B
-83
A
-83
B
-90
A
-90
B
December 16, 2004
CCD18 CCD178 CCD40 CCD50 CCD166
3.75
-0.37
0.68
-3.46
-0.42
0.61
-0.4
6.77
0.12
0.09
0.20
0.44
5.65
0.14
0.10
0.18
0.19
1.73
0.02
0.07
-0.19
1.51
0.04
0.07
-TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
3
TV results
SMS UV01: 12 x 3000s darks @ T=-82C
Images were overscan corrected. Statistics were run on each quadrant, on all
pixels and on pixels that had been 3 sigma-clipped three times. Means and
medians were converted to e-/pix/hr using exptime and assuming gain 1.5.
No clipping
With clipping
Ampli
#
mean
stdev
median
min
max
Ampli
#
mean
stdev
median
min
max
A
12
0.50
0.54
0.35
-0.16
1.97
A
12
0.50
0.54
0.35
-0.16
1.97
B
12
0.33
0.50
0.33
-0.99
0.93
B
12
0.33
0.50
0.33
-0.99
0.93
C
12
0.33
0.33
0.26
-0.08
0.96
C
12
0.33
0.33
0.26
-0.08
0.96
D
12
0.40
0.41
0.29
-0.21
1.09
D
12
0.40
0.41
0.29
-0.21
1.09
Note: TV data are not bias subtracted
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
4
Dark current map
iu010304r_0426720152, 3000sec dark, overscan removed, image linear stretch, ±10DN
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
5
Dark current histograms
From 3000sec dark, overscan-corrected.
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
6
UVIS readnoise
CEI SPECs
-read noise < 4.0 e/pix; goal < 3.0 e/pix
DCL results for CCD43-178
DCL test conditions: 1s darks, frames overscan corrected.
Results from gaussian fit to the histogram.
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
7
UVIS BIAS
iu010301r_0426718291, overscan removed, bias image, linear stretch, ±10DN
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
8
TV results
SMS UV01.
From overscan regions:
Ampli
#
mean
stdev
median
min
max
A
29
3.17
0.03
3.18
3.08
3.20
B
29
3.23
0.04
3.24
3.07
3.26
C
29
3.11
0.03
3.12
2.99
3.13
D
29
3.24
0.02
3.25
3.16
3.27
- Method: Average readnoise (e-/pix), gain=1.5 Computed as std deviation of 26 (of 30) virtual overscan cols x
2032 rows.
- Dataset: set of 29 files composed by 15 biases, 12 long darks (3000 sec), two short darks (1000). 21 were taken
Sep6 (-82), 4 on Sep9 (-93), 4 on Sep23 (-82)
Science area:
(preliminary)
December 16, 2004
Ampli
A
3.01
B
3.07
C
2.98
D
3.08
Method: standard deviation of difference of two long darks,
3 x 3sigma clipping (~99.5% of pixels)
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
9
UVIS gain
CEIS: “Four gain shall be selectable in increment of 1, 1.5, 2, and 4 e/adu”
SMS UV03
“Gain as function of temperature” was done once during TV, at –82 C.
Images for relative gain measurements: all full-frame, unbinned - two flats, two biases at each gain
Relative to gain 1.5, all pixels, overscan-subtracted:
Absolute
G=1.5
G=1
G=2
G=4
A
1.02±0.01
2.09±0.01
4.28±0.02
A
1.55±0.01
B
1.04±0.01
2.15±0.05
4.39±0.48
B
1.57±0.01
C
1.01±0.01
2.10±0.01
4.28±0.02
C
1.59±0.003
D
1.02±0.01
2.10±0.01
4.30±0.02
D
1.53±0.01
Notes:
1. Same ratios are found if pixels are clipped (3sigma), corrected for bias, or both
2. Preliminar measure of absolute gain from mean/variance on small central section of a couple flats
from linearity proposal. Gain errors not yet propagated appropriately, real error likely larger.
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
10
UVIS Linearity
CEI SPECs
- Full well > 50,000 e/pix; goal > 85,000 e/pix
- Linear to <5% (correctable to <0.3%) over 100 to 50,000 e/pix, independent on exp.time
DCL RESULTS (CCD43-178)
- departure from linearity
- Full Well
Channel A: 83,300 - 89,700 e
Channel B: 82,300 - 87,000 e
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
11
TV results
SMS UV04, UV05 Amp. A (chip 178).
Preliminary result based on point source images
- Full well:
criteria
avg (5x5 area)
3% from linear ~66800 e5%
~67500 eDecember 16, 2004
min
63858.5
65524.4
max
69738.6
70008.
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
12
Departure from linearity
DCL
Thermal vac
TV and DCL results are consistent
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
13
IR Dark current
CEI Specs
- total dark+background in any filter <0.4 e/pix/sec; goal 0.1 e/pix/sec
- read noise <15.0 e/pix (goal < 10 e/pix) in single read (21 e/pix CDS)
- amp glow < 10 e/pix/read at detector center
- bias level in single quadrant correctable to <3 e rms (goal <1 e rms)
DCL measure
dark current = 0.04e/s/pix
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
14
TV results
IR01S01
IR01S02
10/10/2004 10:52 18405 18406
10/10/2004 12:01 18407 18408
10/10/2004 15:58 18409 18410
IR01S03
9/7/2004 18:38 10668 10685
Dump Method
User Comments
9/18/2004 9:38 13264 13281
Parallel
IR01S02: Darks at Non-Nominal Temperature
9/23/2004 9:14
14161
14169
Iterations Detector Target Type Filter
Gain
Exp Time Amp
9/23/2004
14170
14178
1
IR
Dark
2.5
IR01S04
9/8/2004
0:20
10686
10700
1
IR
Dark
2.5
9/18/2004 15:20 13282 13296
IR01S05
9/8/2004 7:58 10701 10715
9/8/2004 14:49 10716 10725
9/18/2004 21:12 13297 13308
IR01S06
9/8/2004 18:30 10728 10729
9/8/2004 21:13 10730 10731
9/9/2004 0:08 10732 10733
9/9/2004 3:15 10734 10735
9/9/2004 6:30 10736 10737
9/16/2004 20:12 12555 12556
9/16/2004 21:36 12557 12558
9/16/2004 23:05 12559 12560
9/17/2004 0:38 12561 12562
9/17/2004 1:45 12563 12564
IR01S07
9/23/2004 12:20 14179 14288
9/23/2004 20:38 14293 14347
IR01S08
10/8/2004 13:18 18228 18262
IR01S09
10/17/2004 0:25 22388 22449
December 16, 2004
0
0
2
2
2
6
18
OS Configuration Script
18
None
9
Charge Injection X-Size Y-Size X-Corner
Y-Corner
9
54
15
15
30
15
CE=-36
10
CE=-36, -34
12
37
2
CE=-34
2
CE=-36
2
CE=-38
2
CE=-40
2
CE=-36
2
2
2
2
2
20
110
55 165
35
35
62
62
Binning
Sample Sequence
STEP400
RAPID
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
N-Readouts
Subsize
15 FULL
15 FULL
15
Dark current
Thermal model prediction: 0.025e/s/pix from the cold enclosure
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
16
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
17
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
18
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
19
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
20
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
21
Dark current map
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
22
Background test
1.6
Extra background measured in
F160W and G141
1.4
1.2
1
Using measured enclosure
temperatures the background model
predicts 0.215e/s/pix on orbit in F160W
0.8
0.6
0.4
0.2
0
0
2000
4000
6000
8000
10000
IRFPATMP
12000
-122.7
-122.8
Oscillation of dark current level
with period ~800s
-122.9
-123
-123.1
-123.2
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
15:47:04
15:35:07
23
15:41:08
15:29:08
15:23:12
15:17:13
15:11:22
15:05:23
14:59:27
14:53:32
14:47:33
14:41:37
14:35:37
14:29:38
14:23:42
14:17:43
14:11:53
14:05:53
13:59:57
13:54:01
13:48:02
13:42:04
13:36:07
13:30:07
-123.3
13:24:09
Dark current oscillation is correlated with
FPA temp
Readout noise
CEI SPECs
- Full well > 50,000 e/pix; goal > 85,000 e/pix
- Linear to <5% (correctable to <0.3%) over 100 to 50,000 e/pix, independent on exp.time
DCL RESULTS Read Noise 30 min (e-) : 15.2 e/pix (single sampling)
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
24
TV results
SMS IR01S02
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
25
Readout noise map
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
26
IR Gain
CEIS: “Four gain settings […] selectable in increment of 2, 2.5, 3, and 4 e/adu”
TV results at Gain = 2.5 e/adu:
Quadrant
Gain (e/adu)
1
2
3
4
2.55
2.64
2.59
2.59
(DCL)
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
27
IR Linearity
CEI Specs:
- full well >100,000 e/pix; goal >150,000 e/pix
- linearity <5% (correctable to <0.3%) over 100-70,000 e/pix
DCL results
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
28
TV results
TV: SMS IR03S02 “Linearity at gain = 2 e/adu”
5% non-linearity at ~93,000e-
December 16, 2004
TIPS Meeting
"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."
29