STIS Cycle-20 Calibration Phase-1
Last Revised:
Proposal ID:
Title:
PI:
Co-I(s):
11/13/12
13149
STIS/MAMA Fold Distribution
T. Wheeler
A. Welty
--------------------------------------------------------------------------# Orbit estimates are TOTAL for all of Cycle-20
Total Prime Orbits:
External Parallel Orbits:
Internals or no-impact orbits:
Comments on orbit estimate:
0
0
2
2 orbit per visit
--------------------------------------------------------------------------# This section should be written with a GO audience in mind -- use
# Calibration plans in WFPC-2 handbook as a guide.
Purpose: The performance of MAMA microchannel plates can be monitored using a
MAMA fold analysis procedure that provides a measurement of the distribution
of charge cloud sizes incident upon the anode giving some measure of change
in the pulse-height distribution of the MCP and, therefore, MCP gain.
Description: While globally illuminating the detector with a flat field, the
valid event (VE) rate counter is monitored while various combinations of row
and column folds are selected. The process is implemented using special
commanding and is the same for the FUV and NUV MAMAs with the exception of
the gratings/aperture/lamp combinations used for flat field illumination.
This proposal executes the same steps as Cycle 19 proposal 12778 and is
described in STIS ISR 98-02R.
Accuracy: 95%
Comments on Accuracy: Position of the peak in the fold distribution can be
measured to about 5% accuracy from this procedure.
Products: Fold Analysis findings are reported to the STIS Science Team and V.
Argabright of Ball Aerospace after completion of analysis, typically one-two
weeks after the execution of the test.
--------------------------------------------------------------------------# Link to Cycle 20 Science
# Use the GO + GTO Phase 1 exposure listing and derived statistics
# posted on WWW.
Fraction of science programs supported by this calibration: 76.9% of STIS
prime exposures use MAMAs, 100% of STIS SNAP exposures use MAMAs.
List categories of science which can't be executed until after this
proposal:
None
why:
This is a health monitoring proposal and not
an enabling or calibration proposal.
List categories of science which are best performed contemporaneous with
this proposal:
None
why:
n/a
--------------------------------------------------------------------------# THE REST OF THIS FORM IS FOR INTERNAL USE
--------------------------------------------------------------------------Observation summary: Globally illuminate the detector with a flat field.
Monitor the valid event (VE) rate counter while various combinations of row
and column folds are selected. The process is the same for the FUV and NUV
MAMAs with the exception of the gratings/aperture/lamp combinations used for
flat field illumination.
# Target information (copy for each target)
Target Name.
: n/a (internal)
RA.
: n/a
Dec.
: n/a
Flux (and units).
: n/a
Visibility window (if known or relevant): n/a
Comment on choice of target
: n/a
#
#
#
#
#
#
Exposure list plan at the Phase I level. Be as complete as reasonable.
If possible information should be complete enough to allow easy
submission of a Phase 2 from this form. However, if you have to leave
some of the fields blank below, or want to provide the information
in another format, that is acceptable. (Make sure you do the BOP checking
though, as this is a phase-1 issue.)
Table of exposures (copy for each exposure as appropriate/desired):
------------------------------------------------------------------------**** This list of exposures needs to be repeated once every 6 months ****
------------------------------------------------------------------------Note (1)
Bright Object Protection Considerations
(a) This proposal uses aperture/mirror/lamp combinations which are designed
to produce count rates of ~100,000-200,000 count/sec. They should not
be changed without consultation with the P.I.
(b) During the execution of the fold analysis some anode folds are
disabled. Consequently, the OR counter does not provide a true
representation of the OR count and so the Software Global Monitor (SGM)
does not trigger until the enabled folds provide enough counts to the
OR counter to trigger the SGM's threshold. To compensate, while the
fold analysis is running the SGM threshold is reduced to 150,000 counts
(130,000 counts are used due to ground system restrictions) in a 1.0
second interval, from its nominal value of 77,000 counts in a 0.1
second interval.
(c) For the reasons discussed in (b) and to prevent light from entering the
hub area, this test should only be run with the STIS external shutter
closed.
Visit 1, Exposure 1: FUV Fold Test Setup
Target or lamp
:
Type of Acquisition
:
Detector for observation
:
Operating mode
:
Spectral Element
:
Aperture
:
Central Wavelength
:
Exposure Time
:
Dark
n/a
FUV MAMA (M1)
Data
n/a
n/a
n/a
240s
Number of Iterations
: 1
BOP Predicted Local Count Rate for MAMA : Note (1)
BOP Predicted Global Count Rate for MAMA: Note (1)
ETC PID IDs for Count Rates
:
Special Requirements or options
: Special Commanding
Comments: Sequence 1-3 NON-INT
Set SGM Threshold = 15000, Integration Period = 0.1 s
Configure Mechanisms
Turn on HITM2 lamp at 10mA current
Special commanding: Instruction = EOFOLDSET1
Visit 1, Exposure 2: FUV Fold Test Accum
Target or lamp
: Dark
Type of Acquisition
: n/a
Detector for observation
: FUV MAMA (M1)
Operating mode
: Accum
Spectral Element
: MIRROR
Aperture
: F25ND3
Central Wavelength
: n/a
Exposure Time
: 300s
Number of Iterations
: 1
BOP Predicted Local Count Rate for MAMA : Note (1)
BOP Predicted Global Count Rate for MAMA: Note (1)
ETC PID IDs for Count Rates
:
Special Requirements or options
: Special Commanding
Comments: This image is a flat field exposure with the HITM2 using special
commanding so that the lamp remains on after the exposure.
Visit 1, Exposure 3: FUV Fold Test
Target or lamp
: Dark
Type of Acquisition
: n/a
Detector for observation
: FUV MAMA (M1)
Operating mode
: Data
Spectral Element
: MIRROR
Aperture
: F25ND3
Central Wavelength
: n/a
Exposure Time
: 2300s
Number of Iterations
: 1
BOP Predicted Local Count Rate for MAMA : Note (1)
BOP Predicted Global Count Rate for MAMA: Note (1)
ETC PID IDs for Count Rates
:
Special Requirements or options
: Special Commanding
Comments: Special commanding: Instruction = EOFOLDTST1 – See below for
details.
Set SGM Threshold = 130000, Integration period = 1.0 secs
(a) Collect counter samples during flat field illumination
Collect 5 samples X events
Collect 5 samples Y events
Collect 5 samples Z events
Collect 5 samples W events
Collect 5 samples VE events
Collect 5 samples EV events
Collect 5 samples OR events
(b) Disable MAMA Folds: C2, C3, C4, C5, C6, R2, R3, R4, R5, R6
(c) Conduct fold analysis
Collect 5 samples VE for following 19 combinations of MAMA folds:
(1) Enabled: C2, R2; Disabled: C3, C4, C5, C6, R3, R4, R5, R6
(d)
(e)
(f)
(g)
(h)
(2) Enabled: C2, R3; Disabled: C3, C4, C5, C6, R2, R4, R5, R6
(3) Enabled: C3, R2; Disabled: C2, C4, C5, C6, R3, R4, R5, R6
(4) Enabled: C2, R4; Disabled: C3, C4, C5, C6, R2, R3, R5, R6
(5) Enabled: C3, R3; Disabled: C2, C4, C5, C6, R2, R4, R5, R6
(6) Enabled: C4, R2; Disabled: C2, C3, C5, C6, R3, R4, R5, R6
(7) Enabled: C3, R4; Disabled: C2, C4, C5, C6, R2, R3, R5, R6
(8) Enabled: C4, R3; Disabled: C2, C3, C5, C6, R2, R4, R5, R6
(9) Enabled: C3, R5; Disabled: C2, C4, C5, C6, R2, R3, R4, R6
(10) Enabled: C4, R4; Disabled: C2, C3, C5, C6, R2, R3, R5, R6
(11) Enabled: C5, R3; Disabled: C2, C3, C4, C6, R2, R4, R5, R6
(12) Enabled: C4, R5; Disabled: C2, C3, C5, C6, R2, R3, R4, R6
(13) Enabled: C5, R4; Disabled: C2, C3, C4, C6, R2, R3, R5, R6
(14) Enabled: C4, R6; Disabled: C2, C3, C5, C6, R2, R3, R4, R5
(15) Enabled: C5, R5; Disabled: C2, C3, C4, C6, R2, R3, R4, R6
(16) Enabled: C6, R4; Disabled: C2, C3, C4, C5, R2, R3, R5, R6
(17) Enabled: C5, R6; Disabled: C2, C3, C4, C6, R2, R3, R4, R5
(18) Enabled: C6, R5; Disabled: C2, C3, C4, C5, R2, R3, R4, R6
(19) Enabled: C6, R6; Disabled: C2, C3, C4, C5, R2, R3, R4, R5
Enable MAMA folds C2, C3, C4, C5, C6, R2, R3, R4, R5, R6
at completion of exposure.
Check lamp stability by checking EV and VE
Collect 5 samples events (EV) to check lamp stability
Collect 5 samples Valid Events (VE) to check lamp stability
Turn off HITM2 lamp
Collect event counter data for detector dark count rate
Collect 5 samples X dark events
Collect 5 samples Y dark events
Collect 5 samples Z dark events
Collect 5 samples W dark events
Collect 5 samples VE dark events
Collect 5 samples EV dark events
Collect 5 samples OR dark events
At completion of procedure reset SGM to nominal operating level
Visit 2, Exposure 1: NUV Fold Test - Fold Test Setup
Target or lamp
: Dark
Type of Acquisition
: n/a
Detector for observation
: NUV MAMA (M2)
Operating mode
: Data
Spectral Element
: n/a
Aperture
: n/a
Central Wavelength
: n/a
Exposure Time
: 240s
Number of Iterations
: 1
BOP Predicted Local Count Rate for MAMA : Note (1)
BOP Predicted Global Count Rate for MAMA: Note (1)
ETC PID IDs for Count Rates
:
Special Requirements or options
: Special Commanding
Comments: Sequence 1-3 NON-INT
Set SGM Threshold = 15000, Integration Period = 0.1 s
Configure Mechanisms
Turn on HITM1 lamp at 3.8mA current
Special commanding: Instruction = EOFOLDSET2
Visit 2, Exposure 2: NUV Fold Test - Accum
Target or lamp
: Dark
Type of Acquisition
: n/a
Detector for observation
: NUV MAMA (M2)
Operating mode
: Accum
Spectral Element
: MIRROR
Aperture
: F25ND3
Central Wavelength
: NONE
Exposure Time
: 120s
Number of Iterations
: 1
BOP Predicted Local Count Rate for MAMA : Note (1)
BOP Predicted Global Count Rate for MAMA: Note (1)
ETC PID IDs for Count Rates
:
Special Requirements or options
: Special Commanding
Comments: This image is a flat field exposure with the HITM1 using special
commanding so that the lamp remains on after the exposure.
Visit 2, Exposure 3: NUV Fold Test - Fold Test
Target or lamp
: Dark
Type of Acquisition
: n/a
Detector for observation
: NUV MAMA (M2)
Operating mode
: Data
Spectral Element
: MIRROR
Aperture
: F25ND3
Central Wavelength
: n/a
Exposure Time
: 2300s
Number of Iterations
: 1
BOP Predicted Local Count Rate for MAMA : Note (1)
BOP Predicted Global Count Rate for MAMA: Note (1)
ETC PID IDs for Count Rates
:
Special Requirements or options
: Special Commanding
Comments: Special commanding: Instruction = EOFOLDTST12 – See below for
details.
Set SGM Threshold = 130000, Integration period = 1.0 secs
(a) Collect counter samples during flat field illumination
Collect 5 samples X events
Collect 5 samples Y events
Collect 5 samples Z events
Collect 5 samples W events
Collect 5 samples VE events
Collect 5 samples EV events
Collect 5 samples OR events
(b) Disable MAMA Folds: C2, C3, C4, C5, C6, R2, R3, R4, R5, R6
(c) Conduct fold analysis
Collect 5 samples VE for following 19 combinations of MAMA folds:
(1) Enabled: C2, R2; Disabled: C3, C4, C5, C6, R3, R4, R5, R6
(2) Enabled: C2, R3; Disabled: C3, C4, C5, C6, R2, R4, R5, R6
(3) Enabled: C3, R2; Disabled: C2, C4, C5, C6, R3, R4, R5, R6
(4) Enabled: C2, R4; Disabled: C3, C4, C5, C6, R2, R3, R5, R6
(5) Enabled: C3, R3; Disabled: C2, C4, C5, C6, R2, R4, R5, R6
(6) Enabled: C4, R2; Disabled: C2, C3, C5, C6, R3, R4, R5, R6
(7) Enabled: C3, R4; Disabled: C2, C4, C5, C6, R2, R3, R5, R6
(8) Enabled: C4, R3; Disabled: C2, C3, C5, C6, R2, R4, R5, R6
(9) Enabled: C3, R5; Disabled: C2, C4, C5, C6, R2, R3, R4, R6
(10) Enabled: C4, R4; Disabled: C2, C3, C5, C6, R2, R3, R5, R6
(11) Enabled: C5, R3; Disabled: C2, C3, C4, C6, R2, R4, R5, R6
(12) Enabled: C4, R5; Disabled: C2, C3, C5, C6, R2, R3, R4, R6
(13) Enabled: C5, R4; Disabled: C2, C3, C4, C6, R2, R3, R5, R6
(14) Enabled: C4, R6; Disabled: C2, C3, C5, C6, R2, R3, R4, R5
(15) Enabled: C5, R5; Disabled: C2, C3, C4, C6, R2, R3, R4, R6
(d)
(e)
(f)
(g)
(h)
(16) Enabled: C6, R4; Disabled: C2, C3, C4, C5, R2, R3, R5, R6
(17) Enabled: C5, R6; Disabled: C2, C3, C4, C6, R2, R3, R4, R5
(18) Enabled: C6, R5; Disabled: C2, C3, C4, C5, R2, R3, R4, R6
(19) Enabled: C6, R6; Disabled: C2, C3, C4, C5, R2, R3, R4, R5
Enable MAMA folds C2, C3, C4, C5, C6, R2, R3, R4, R5, R6
at completion of exposure.
Check lamp stability by checking EV and VE
Collect 5 samples events (EV) to check lamp stability
Collect 5 samples Valid Events (VE) to check lamp stability
Turn off HITM1 lamp
Collect event counter data for detector dark count rate
Collect 5 samples X dark events
Collect 5 samples Y dark events
Collect 5 samples Z dark events
Collect 5 samples W dark events
Collect 5 samples VE dark events
Collect 5 samples EV dark events
Collect 5 samples OR dark events
At completion of procedure reset SGM to nominal operating level
--------------------------------------------------------------------------# Special needs of this proposal?
Scheduling: This proposal should execute in the spring of every year. The
exposures listed are for one execution only.
Prerequisites
PDB update?
On-board table update?
: None
N
N
# Special Requirements:
Real time?
N
Special commanding?
Y
Quick Data turnaround?
N
Special timing required? N
Other?
N
Describe (& justify) special requirements: Special commanding is required to
implement the requirement of this test.
------------------------------------------------------------------------# Analysis Plan
Expected FTE weeks for analysis:
Required turnaround on analysis (weeks):
Data volume (Mb needed for analysis):
Special software needed for analysis? (Describe):
Description of analysis Plans:
0.2
2
n/a
none
(1-2 paragraphs):
The analysis will be carried by the Engineering Team when the engineering
data becomes available approximately two days after each visit. The time-tag
images are examined for unusual spatial or temporal features. The fold test
results are reported to the STIS Science Team and V. Argabright of Ball
Aerospace.