Proposal 11452 (STScI Edit Number: 1, Created: Wednesday, July 30, 2008 8:11:48 PM EST) - Overview
11452 - UVIS Flat Field Uniformity
Cycle: 17, Proposal Category: SM4/WFC3
(Availability Mode: RESTRICTED)
INVESTIGATORS
Name
Ms. Jessica Kim Quijano (PI)
Dr. Linda Dressel (CoI)
Institution
Space Telescope Science Institute
Space Telescope Science Institute
E-Mail
VISITS
Visit Targets used in Visit
Configurations used in Visit
Orbits Used Last Orbit Planner Run
01
(1) 47TUC
WFC3/UVIS
5
30-Jul-2008 21:11:10.0
OP Current
with Visit?
yes
02
(2) OMEGA-CEN
WFC3/UVIS
6
30-Jul-2008 21:11:41.0
yes
11 Total Orbits Used
ABSTRACT
The stability and uniformity of the low-frequency flat fields (L-flat) of the UVIS detector will be assessed by using multiple-pointing observations of
the globular clusters 47 Tucanae (NGC104) and Omega Centauri (NGC5139), thus imaging moderately dense stellar fields. By placing the same star
over different portions of the detector and measuring relative changes in its brightness, it will be possible to determine local variations in the response
of the UVIS detector.
Based on previous experience with STIS and ACS, it is deemed that a total of 9 different pointings will suffice to provide adequate characterization
of the flat field stability in any given band. For each filter to be tested, the baseline consists of 9 pointings in a 3X3 box pattern with dither steps of
Proposal 11452 (STScI Edit Number: 1, Created: Wednesday, July 30, 2008 8:11:48 PM EST) - Overview
about 25% of the FOV, or 40.5", in either the x or y direction (useful also for CTE measurements, if needed in the future). During SMOV, the
complement of filters to be tested is limited to the following 6 filters: F225W, F275W, F336W, for Omega Cen, and F438W, F606W, and F814W for
47 Tuc. Three long exposures for each target are arranged such that the initial dither position is observed with the appropriate filters for that target
within one orbit at a single pointing, so that filter-to-filter differences in the observed star positions can be checked.
In addition to the 9 baseline exposures, two sets of short exposures will be taken:
a) one short exposure will be taken of OmegaCen with each of the visible filters (F438W, F606W and F814W) in order to check the geometric
distortion solution to be obtained with the data from proposal 11444;
b) for each target, a single short exposure will be taken with each filter to facilitate the study of the PSF as a function of position on the detector by
providing unsaturated images of sparsely-spaced bright stars.
This proposal corresponds to Activity Description ID WF39. It should execute only after the following proposal has executed:
WF21 - 11434
OBSERVING DESCRIPTION
For 47 Tuc, three short and three long exposures of F438W, F814W and F606W filters are interleaved at the zeroth position. This exposure and filter
sequence at the zeroth position is done in this way for two purposes: a) to manage buffer dumps by interleaving the short exposures intended for
determination of the PSF as a function of position on the detector; and b) to provide a way to determine offsets introduced by each filter while
observing the exact same field without moving the telescope. It is important that the Orbit 1 of Visit 1 be done at the exact same pointing. After those
zeroth position observations are done, the remaining dither positions (1-8) for F606W, F814W and F438W are taken, grouped by filter. This
observing strategy was designed to maximize orbit time, because overheads increase when switching filters.
For OmegaCen, three short exposures with the visible filters are interleaved with the three long exposures with the UV filters at the zeroth position.
This exposure and filter sequence at the zeroth position is done for two purposes: a) to manage buffer dumps by interleaving the short exposures
intended for checking the geometric distortion; and b) to provide a way to determine offsets introduced by each of the three UV filters while
2
Proposal 11452 (STScI Edit Number: 1, Created: Wednesday, July 30, 2008 8:11:48 PM EST) - Overview
observing the exact same field, without moving the telescope. It is important that the Orbit 1 of Visit 2 be done at the exact same pointing. After
those zeroth position observations are done, the remaining dither positions (1-8) for F225W, F336W and F275W are taken, grouped by filter. At the
end of each filter sequence, a short exposure is taken at the eighth position. These short exposures are intended for determination of PSF as a function
of position on the detector. This observing strategy was designed to maximize orbit time, because overheads increase when switching filters.
CALIBRATION JUSTIFICATION
The data will be used to generate on-orbit updates for the WFC3 calibration pipeline flatfield reference files.
ADDITIONAL COMMENTS
Usage of the same guide stars within each visit is desirable, but not a requirement.
3
Exposures
Fixed Targets
Visit
Proposal 11452 - Visit 01 - UVIS Flat Field Uniformity
Proposal 11452, Visit 01, scheduling
Diagnostic Status: No Diagnostics
Scientific Instruments: WFC3/UVIS
Special Requirements: (none)
#
Name
Target Coordinates
Targ. Coord. Corrections
(1)
47TUC
RA: 00 22 38.5000 (5.6604167d)
Alt Name1: NGC104
Dec: -72 04 4.00 (-72.06778d)
Equinox: J2000
Comments: Field 6' W of cluster centre. Same target as used by ACS WFC L-flat calibration program.
#
1
Label
Target
47 Tuc - F43 (1) 47TUC
8W 0 short
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
Spectral Els.
F438W
Opt. Params.
CR-SPLIT=NO
2
47 Tuc - F43 (1) 47TUC
8W 0
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
3
47 Tuc - F81 (1) 47TUC
4W 0 short
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
4
47 Tuc - F81 (1) 47TUC
4W 0
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
5
47 Tuc - F60 (1) 47TUC
6W 0
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
6
47 Tuc - F60 (1) 47TUC
6W 0 short
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
7
47 Tuc - F60 (1) 47TUC
6W 1
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
8
47 Tuc - F60 (1) 47TUC
6W 2
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
9
47 Tuc - F60 (1) 47TUC
6W 3
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
10
47 Tuc - F60 (1) 47TUC
6W 4
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
11
47 Tuc - F60 (1) 47TUC
6W 5
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
12
47 Tuc - F60 (1) 47TUC
6W 6
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
13
47 Tuc - F60 (1) 47TUC
6W 7
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
14
47 Tuc - F60 (1) 47TUC
6W 8
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
4
Thu Jul 31 01:11:49 GMT 2008
Fluxes
V=14.4+/-0.1
Miscellaneous
Reference Frame: ICRS
Special Reqs.
Groups
Exp. Time/[Actual Dur.]
GS ACQ SCENARI Sequence 1-6 Non-In 35.0 Secs
O BASE1B3
t
[==>]
Sequence 1-6 Non-In 350.0 Secs
t
[==>]
Sequence 1-6 Non-In 35.0 Secs
t
[==>]
Sequence 1-6 Non-In 350.0 Secs
t
[==>]
Sequence 1-6 Non-In 350.0 Secs
t
[==>]
Sequence 1-6 Non-In 35.0 Secs
t
[==>]
POS TARG 40.5,0.0
350.0 Secs
[==>]
POS TARG 40.5,-40
350.0 Secs
.5
[==>]
POS TARG 0.0,-40.
350.0 Secs
5
[==>]
POS TARG -40.5,-4
350.0 Secs
0.5
[==>]
POS TARG -40.5,0.
350.0 Secs
0
[==>]
POS TARG -40.5,40
350.0 Secs
.5
[==>]
POS TARG 0.0,40.5
350.0 Secs
[==>]
POS TARG 40.5,40.
350.0 Secs
5
[==>]
Orbit
[1]
[1]
[1]
[1]
[1]
[1]
[2]
[2]
[2]
[2]
[2]
[2]
[3]
[3]
Exposures (continued)
Proposal 11452 - Visit 01 - UVIS Flat Field Uniformity
#
15
Label
Target
47 Tuc - F81 (1) 47TUC
4W 1
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
Spectral Els.
F814W
Opt. Params.
CR-SPLIT=NO
Special Reqs.
Groups
POS TARG 40.5,0.0
16
47 Tuc - F81 (1) 47TUC
4W 2
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
POS TARG 40.5,-40
.5
17
47 Tuc - F81 (1) 47TUC
4W 3
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
POS TARG 0.0,-40.
5
18
47 Tuc - F81 (1) 47TUC
4W 4
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
POS TARG -40.5,-4
0.5
19
47 Tuc - F81 (1) 47TUC
4W 5
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
POS TARG -40.5,0.
0
20
47 Tuc - F81 (1) 47TUC
4W 6
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
POS TARG -40.5,40
.5
21
47 Tuc - F81 (1) 47TUC
4W 7
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
POS TARG 0.0,40.5
22
47 Tuc - F81 (1) 47TUC
4W 8
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
POS TARG 40.5,40.
5
23
47 Tuc - F43 (1) 47TUC
8W 1
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG 40.5,0.0
24
47 Tuc - F43 (1) 47TUC
8W 2
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG 40.5,-40
.5
25
47 Tuc - F43 (1) 47TUC
8W 3
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG 0.0,-40.
5
26
47 Tuc - F43 (1) 47TUC
8W 4
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG -40.5,-4
0.5
27
47 Tuc - F43 (1) 47TUC
8W 5
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG -40.5,0.
0
28
47 Tuc - F43 (1) 47TUC
8W 6
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG -40.5,40
.5
29
47 Tuc - F43 (1) 47TUC
8W 7
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG 0.0,40.5
30
47 Tuc - F43 (1) 47TUC
8W 8
WFC3/UVIS, ACCUM, UVIS
F438W
CR-SPLIT=NO
POS TARG 40.5,40.
5
5
Exp. Time/[Actual Dur.]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
Orbit
[3]
[3]
[3]
[3]
[4]
[4]
[4]
[4]
[4]
[4]
[5]
[5]
[5]
[5]
[5]
[5]
Orbit Structure
Proposal 11452 - Visit 01 - UVIS Flat Field Uniformity
6
Orbit Structure (continued)
Proposal 11452 - Visit 01 - UVIS Flat Field Uniformity
7
Orbit Structure (continued)
Proposal 11452 - Visit 01 - UVIS Flat Field Uniformity
8
Orbit Structure (continued)
Proposal 11452 - Visit 01 - UVIS Flat Field Uniformity
9
Orbit Structure (continued)
Proposal 11452 - Visit 01 - UVIS Flat Field Uniformity
10
Fixed Targets
Visit
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
Proposal 11452, Visit 02, scheduling
Diagnostic Status: No Diagnostics
Scientific Instruments: WFC3/UVIS
Special Requirements: (none)
#
Name
Target Coordinates
Targ. Coord. Corrections
(2)
OMEGA-CEN
RA: 13 26 47.2400 (201.6968333d)
Alt Name1: NGC5139
Dec: -47 28 46.45 (-47.47957d)
Equinox: J2000
Comments: This object was generated by the targetselector and retrieved from the NED database. Coordinates from Jay Anderson.
#
1
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
OmegaCen - (2) OMEGA-CEN
F814W 0 sh
ort
OmegaCen - (2) OMEGA-CEN
F336W 0
WFC3/UVIS, ACCUM, UVIS
F814W
CR-SPLIT=NO
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
5
OmegaCen - (2) OMEGA-CEN
F225W 0
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
6
OmegaCen - (2) OMEGA-CEN
F606W 0 sh
ort
OmegaCen - (2) OMEGA-CEN
F225W 1
WFC3/UVIS, ACCUM, UVIS
F606W
CR-SPLIT=NO
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
POS TARG 40.5,0.0
8
OmegaCen - (2) OMEGA-CEN
F225W 2
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
POS TARG 40.5,-40
.5
9
OmegaCen - (2) OMEGA-CEN
F225W 3
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
POS TARG 0.0,-40.
5
10
OmegaCen - (2) OMEGA-CEN
F225W 4
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
POS TARG -40.5,-4
0.5
11
OmegaCen - (2) OMEGA-CEN
F225W 5
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
POS TARG -40.5,0.
0
12
OmegaCen - (2) OMEGA-CEN
F225W 6
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
POS TARG -40.5,40
.5
13
OmegaCen - (2) OMEGA-CEN
F225W 7
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
POS TARG 0.0,40.5
3
Exposures
4
7
Opt. Params.
CR-SPLIT=NO
Fluxes
V=16.8+/-0.1
Label
Target
OmegaCen - (2) OMEGA-CEN
F438W 0 sh
ort
OmegaCen - (2) OMEGA-CEN
F275W 0
2
Spectral Els.
F438W
Thu Jul 31 01:11:53 GMT 2008
11
Miscellaneous
Reference Frame: ICRS
Special Reqs.
Groups
Exp. Time/[Actual Dur.]
GS ACQ SCENARI Sequence 1-6 Non-In 35.0 Secs
O BASE1B3
t
[==>]
Sequence 1-6 Non-In 350.0 Secs
t
[==>]
Sequence 1-6 Non-In 35.0 Secs
t
[==>]
Sequence 1-6 Non-In 350.0 Secs
t
[==>]
Sequence 1-6 Non-In 350.0 Secs
t
[==>]
Sequence 1-6 Non-In 35.0 Secs
t
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
Orbit
[1]
[1]
[1]
[1]
[1]
[1]
[2]
[2]
[2]
[2]
[2]
[2]
[3]
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
#
14
Label
Target
OmegaCen - (2) OMEGA-CEN
F225W 8
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
Spectral Els.
F225W
Opt. Params.
CR-SPLIT=NO
15
OmegaCen - (2) OMEGA-CEN
F225W 8 sh
ort
OmegaCen - (2) OMEGA-CEN
F336W 1
WFC3/UVIS, ACCUM, UVIS
F225W
CR-SPLIT=NO
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG 40.5,0.0
17
OmegaCen - (2) OMEGA-CEN
F336W 2
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG 40.5,-40
.5
18
OmegaCen - (2) OMEGA-CEN
F336W 3
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG 0.0,-40.
5
19
OmegaCen - (2) OMEGA-CEN
F336W 4
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG -40.5,-4
0.5
20
OmegaCen - (2) OMEGA-CEN
F336W 5
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG -40.5,0.
0
21
OmegaCen - (2) OMEGA-CEN
F336W 6
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG -40.5,40
.5
22
OmegaCen - (2) OMEGA-CEN
F336W 7
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG 0.0,40.5
23
OmegaCen - (2) OMEGA-CEN
F336W 8
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG 40.5,40.
5
24
OmegaCen - (2) OMEGA-CEN
F336W 8 sh
ort
OmegaCen - (2) OMEGA-CEN
F275W 1
WFC3/UVIS, ACCUM, UVIS
F336W
CR-SPLIT=NO
POS TARG 40.5,40.
5
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
POS TARG 40.5,0.0
26
OmegaCen - (2) OMEGA-CEN
F275W 2
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
POS TARG 40.5,-40
.5
27
OmegaCen - (2) OMEGA-CEN
F275W 3
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
POS TARG 0.0,-40.
5
28
OmegaCen - (2) OMEGA-CEN
F275W 4
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
POS TARG -40.5,-4
0.5
29
OmegaCen - (2) OMEGA-CEN
F275W 5
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
POS TARG -40.5,0.
0
30
OmegaCen - (2) OMEGA-CEN
F275W 6
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
POS TARG -40.5,40
.5
31
OmegaCen - (2) OMEGA-CEN
F275W 7
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
POS TARG 0.0,40.5
Exposures (continued)
16
25
12
Special Reqs.
Groups
Exp. Time/[Actual Dur.]
POS TARG 40.5,40. Sequence 14-15 Non 350.0 Secs
5
-Int
[==>]
POS TARG 40.5,40. Sequence 14-15 Non 35.0 Secs
5
-Int
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
Sequence 23-24 Non 350.0 Secs
-Int
[==>]
Sequence 23-24 Non 35.0 Secs
-Int
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
350.0 Secs
[==>]
Orbit
[3]
[3]
[3]
[3]
[4]
[4]
[4]
[4]
[4]
[5]
[5]
[5]
[5]
[5]
[6]
[6]
[6]
[6]
#
32
Label
Target
OmegaCen - (2) OMEGA-CEN
F275W 8
Config,Mode,Aperture
WFC3/UVIS, ACCUM, UVIS
Spectral Els.
F275W
Opt. Params.
CR-SPLIT=NO
33
OmegaCen - (2) OMEGA-CEN
F275W 8 sh
ort
WFC3/UVIS, ACCUM, UVIS
F275W
CR-SPLIT=NO
Special Reqs.
Groups
Exp. Time/[Actual Dur.]
POS TARG 40.5,40. Sequence 32-33 Non 350.0 Secs
5
-Int
[==>]
POS TARG 40.5,40. Sequence 32-33 Non 35.0 Secs
5
-Int
[==>]
Orbit
[6]
[6]
Orbit Structure
Exposures (continued)
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
13
Orbit Structure (continued)
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
14
Orbit Structure (continued)
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
15
Orbit Structure (continued)
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
16
Orbit Structure (continued)
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
17
Orbit Structure (continued)
Proposal 11452 - Visit 02 - UVIS Flat Field Uniformity
18