Proposal 13103 (STScI Edit Number: 1, Created: Tuesday, September 11, 2012 8:07:51 PM EST) - Overview
13103 - WFC3/UVIS Anneal
Cycle: 19, Proposal Category: CAL/WFC3
(Availability Mode: RESTRICTED)
INVESTIGATORS
Name
Dr. Sylvia M. Baggett (PI) (Contact)
Dr. John A. Biretta (CoI)
Institution
Space Telescope Science Institute
Space Telescope Science Institute
E-Mail
sbaggett@stsci.edu
biretta@stsci.edu
VISITS
Visit Targets used in Visit
Configurations used in Visit
Orbits Used Last Orbit Planner Run
A1
WFC3/UVIS
2
11-Sep-2012 21:07:26.0
A2
BIAS
DARK
NONE
OP Current
with Visit?
yes
WFC3
1
11-Sep-2012 21:07:31.0
yes
A3
TUNGSTEN
WFC3/UVIS
1
11-Sep-2012 21:07:34.0
yes
A4
BIAS
DARK
DARK
WFC3/UVIS
2
11-Sep-2012 21:07:42.0
yes
WFC3/IR
1
11-Sep-2012 21:07:46.0
yes
A5
7 Total Orbits Used
ABSTRACT
The on-orbit radiation environment of WFC3 continually generates new hot pixels. This proposal performs the procedure required for repairing those
hot pixels in the UVIS CCDs. During an anneal, the two-stage thermo-electric cooler (TEC) is turned off and the four-stage TEC is used as a heater
to bring the UVIS CCDs up to ~20C. As a result of the CCD warmup, a large fraction of the hot pixels are fixed. UVIS bias and dark frames are
taken before and after each anneal, to allow an assessment of the procedure's effectiveness, provide a check of readnoise, bias, global dark current,
1
Proposal 13103 (STScI Edit Number: 1, Created: Tuesday, September 11, 2012 8:07:51 PM EST) - Overview
and hot pixel levels, as well as support hysteresis (bowtie) monitoring and CDBS reference file generation. One IR dark is taken after each anneal, to
provide a check of the IR detector.
OBSERVING DESCRIPTION
The anneal procedures are performed every four weeks. Full-frame, unbinned UVIS bias and dark frames (3 and 5 images, respectively) are obtained
immediately prior to and following each anneal; the data provide a means of monitoring changes due to the detector warmup. In addition, a bowtie
monitor is run directly after the anneal, in the event that hysteresis effects were induced by the warmup. SEQ-WITHIN has been used to ensure that
all visits from a given anneal iteration execute in order. No WFC3 science imaging should be done between the pre- and post-anneal internals.
Due to thermal requirements, the IR detector must be warmed somewhat during a UVIS anneal (from -128 to -90) but the temperature change is kept
to a minimum in order to minimize cycling on the IR, a restricted item. This warming may be discontinued in the future but until then, to evaluate the
state of the IR detector after it has been cooled back down, one SPARS50 dark exposure is taken after each anneal. The IR dark visit is included in
this proposal rather than in the dark monitor proposal in order to ensure the post-anneal linkage. It is placed in its own visit, following the post-anneal
UVIS darks rather than included with the UVIS exposures to facilitate its removal, if warranted, at some later date.
CALIBRATION JUSTIFICATION
The acquired bias and dark frames will be compared to baseline images, readnoise and global dark current will be measured, hot pixel changes will
be monitored, and the effectiveness of each anneal procedure will be evaluated. UVIS dark frames will be inspected for evidence of any hysteresis
(bowtie) effects; the bowtie monitor visit after the anneal also serves as a bowtie check and neutralizer if needed. Bias and dark data will be
combined with that from other proposals to generate superbias and superdark reference files for the calibration pipeline.
ADDITIONAL COMMENTS
This proposal extends the original Cycle 19 anneal proposal through October 2012. The Cycle 20 calibration program will run from Nov 2012 to the
end of Oct 2013.
2
Exposures
Diagnostics
Visit
Proposal 13103 - bias/darks (A1) - WFC3/UVIS Anneal
Proposal 13103, bias/darks (A1)
Diagnostic Status: Warning
Scientific Instruments: WFC3/UVIS
Special Requirements: BETWEEN 08-OCT-2012:00:00:00 AND 12-OCT-2012:23:59:59; SEQ A1,A2,A3,A4,A5 WITHIN 72.0 H
Comments: No WFC3 UVIS science should be scheduled between visits; strongly prefer to have the visits scheduled back-to-back.
(bias/darks (A1)) Warning (Orbit Planner): MAXIMUM DURATION EXCEEDED FOR INTERNAL OR EARTH CALIB SU
#
1
Label
Bias
Target
BIAS
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
Spectral Els.
DEF
2
Bias
BIAS
WFC3/UVIS, ACCUM, UVIS
DEF
3
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
4
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
5
Bias
BIAS
WFC3/UVIS, ACCUM, UVIS
DEF
6
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
7
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
8
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
Opt. Params.
3
Special Reqs.
Wed Sep 12 01:07:52 GMT 2012
Groups
Exp. Time/[Actual Dur.]
0.0 Secs
[==>]
0.0 Secs
[==>]
900.0 Secs
[==>]
900.0 Secs
[==>]
0.0 Secs
[==>]
900.0 Secs
[==>]
900.0 Secs
[==>]
900.0 Secs
[==>]
Orbit
[1]
[1]
[1]
[1]
[1]
[1]
[2]
[2]
Orbit Structure
Proposal 13103 - bias/darks (A1) - WFC3/UVIS Anneal
4
Proposal 13103, anneal procedure (A2)
Diagnostic Status: No Diagnostics
Scientific Instruments: WFC3
Special Requirements: (none)
Comments: Using minimum default value + 1sec.
#
Label
Target
Config,Mode,Aperture
1
Anneal
NONE
WFC3, ANNEAL
Wed Sep 12 01:07:54 GMT 2012
Spectral Els.
Opt. Params.
IRTEMP=COLD
Special Reqs.
Groups
Exp. Time/[Actual Dur.]
0. Secs
[==>]
Orbit
[1]
Orbit Structure
Exposures
Visit
Proposal 13103 - anneal procedure (A2) - WFC3/UVIS Anneal
5
Proposal 13103, bowtie check/fix (A3)
Diagnostic Status: No Diagnostics
Scientific Instruments: WFC3/UVIS
Special Requirements: (none)
#
Label
Target
1
initial check TUNGSTEN
Wed Sep 12 01:07:55 GMT 2012
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
Spectral Els.
F475X
Opt. Params.
BIN=3
2
neutralizer
TUNGSTEN
WFC3/UVIS, ACCUM, UVIS
F475X
BIN=3
3
final check
TUNGSTEN
WFC3/UVIS, ACCUM, UVIS
F475X
BIN=3
Orbit Structure
Exposures
Visit
Proposal 13103 - bowtie check/fix (A3) - WFC3/UVIS Anneal
6
Special Reqs.
Groups
Sequence 1-3 Non-In
t in bowtie check/fix
(A3)
Sequence 1-3 Non-In
t in bowtie check/fix
(A3)
Sequence 1-3 Non-In
t in bowtie check/fix
(A3)
Exp. Time/[Actual Dur.]
1.0 Secs
[==>]
Orbit
[1]
200.0 Secs
[==>]
[1]
1.0 Secs
[==>]
[1]
Exposures
Diagnostics
Visit
Proposal 13103 - bias/darks (A4) - WFC3/UVIS Anneal
Proposal 13103, bias/darks (A4)
Diagnostic Status: Warning
Scientific Instruments: WFC3/UVIS
Special Requirements: (none)
(bias/darks (A4)) Warning (Orbit Planner): MAXIMUM DURATION EXCEEDED FOR INTERNAL OR EARTH CALIB SU
#
1
Label
Bias
Target
BIAS
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
Spectral Els.
DEF
2
Bias
BIAS
WFC3/UVIS, ACCUM, UVIS
DEF
3
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
4
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
5
Bias
BIAS
WFC3/UVIS, ACCUM, UVIS
DEF
6
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
7
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
8
Dark
DARK
WFC3/UVIS, ACCUM, UVIS
DEF
Opt. Params.
7
Special Reqs.
Wed Sep 12 01:07:56 GMT 2012
Groups
Exp. Time/[Actual Dur.]
0.0 Secs
[==>]
0.0 Secs
[==>]
900.0 Secs
[==>]
900.0 Secs
[==>]
0.0 Secs
[==>]
900.0 Secs
[==>]
900.0 Secs
[==>]
900.0 Secs
[==>]
Orbit
[1]
[1]
[1]
[1]
[1]
[1]
[2]
[2]
Orbit Structure
Proposal 13103 - bias/darks (A4) - WFC3/UVIS Anneal
8
Proposal 13103, IR dark (A5)
Diagnostic Status: No Diagnostics
Scientific Instruments: WFC3/IR
Special Requirements: (none)
#
Label
Target
1
DARK
Wed Sep 12 01:07:58 GMT 2012
Config,Mode,Aperture
WFC3/IR, MULTIACCUM, IR
Spectral Els.
BLANK
Opt. Params.
Special Reqs.
SAMP-SEQ=SPARS
50;
NSAMP=15
Orbit Structure
Exposures
Visit
Proposal 13103 - IR dark (A5) - WFC3/UVIS Anneal
9
Groups
Exp. Time/[Actual Dur.]
Orbit
[==>]
[1]