Telescope and Instrument Performance
Summary (TIPS)
18 April 2002
AGENDA
1.
2.
3.
4.
5.
HOD Perspective
ACS Update
NCS Update
STIS Update
HST Focus Monitoring
David Soderblom
Mark Clampin
Larry Petro
Kailash Sahu
Russell Makidon
Next TIPS Meeting: 02 May 2002
Scheduling the Cycle 11 Large and Treasury Programs
David Soderblom and Denise Taylor, HOD
Preparations for scheduling the large and Treasury programs began in
December 2001, when Institute instrument scientists and scheduling teams
met to discuss special needs for these programs. Instrument calibration
plans and HST observation planning have been developed to maximize
scientific return of these programs.
Meetings and telecons with PIs and Co-Is took place in January to
understand better the scientific goals of each program, and to advise on
Phase II development. Communication continues via email, telephone, and
personal contact between PIs, Co-Is, Program Coordinators and Contact
Scientists.
Phase II proposals were submitted in February, and are being processed
and planned for scheduling. The GOODS CDF observations are not yet in
the Long Range Plan (LRP), due to some minor scheduling issues, which
the GOODS team is working to resolve. All other large and Treasury
programs are in the LRP.
Resources Needed for Large and Treasury Programs
Combined
9382
Rao
9401
Cote
9433
Bernstein
9453
Brown
9500
Rix
9420
Davidson
9455
Peterson
9583
GOODS
HDF-N
Current Long Range Plan for Cycle 11
Parallels in Cycle 11
• Six Pure Parallel programs accepted for Cycle 11:
4 use ACS, 1 NICMOS, 1 WFPC2
• Essentially no demand for STIS and WFPC2
parallels, but they are by far the most available
• Parallel Observations with Space Telescope
(POST) to meet May 14 to plan Cycle 11
parallels; includes external and internal
astronomers
• S. Malhotra named Parallels Project Scientist
Page 1
SMOV Status
• SMOV is proceeding on-track
• Key programs executed
–
–
–
–
–
–
ERO program
Geometric distortion program completed
ACS to FGS alignment
Image quality
ACS Sensitivity
HRC Flat fields
• ERO press conference: April 30th
Page 2
SMOV
Page 3
Geometric Distortion
•
Added 4th order polynomial terms to the solution for the WFC. The
distortion fits are now good to approximately 0.1 pixels (RMS of 0.05
pixels)[Lindler & Meurer]
Page 4
WFC hot Pixel Growth Rates
• WFC hot pixel growth rate is ~170 pixels/day (Riess)
– Anneal repaired ~45% of hot pixels (~80% in HRC)
Page 5
Sensitivity
•
Initial results for HRC sensitivity program (Pavlovsky and DeMarchi)
– Target GD71
– Filters in general agreement with predictions
– Z Band filter is probably high due to absence of ground-based
measurements beyond 1000 nm.
– Near-UV measurements are under investigation
Page 6
CALACS
• Minor problems are being identified and fixed in CALACS
– Quickfix for CALACS 13.4D
– Change to sky determination
– OPUS 14.0 due mid-June
– Keyword rule modifications
– Keyword database
– Keyword Population
– Reference files
– New files ready for delivery
– Bad pixel table, Bias, Dark, CR-Reject
– WFC and HRC flat field files need updates
Page 7
SBC
• SBC anomalous recovery was terminated after initial LVPS
turn-on
• Ball Aerospace expressed concern that LVPS really needed 24
hours to outgas at operating temperature before HV switch-on
• Impact:
– Did not bring SBC on-line
– Lost this weeks contamination monitor
– Proposal has to be re-worked with special commanding before
being re-scheduled
– Moved up Grism & Ramp filter proposals
Page 8
Gyro-3
• Gyro-3 glitch has resulted in at least 3 visits of observations
from 9018 being lost
– These observations are used to build L-flats using 47 Tuc images
– Smearing of images precludes photometry
• Data Compression
– Analysis shows we can use factor of 2 for bias and darks
– Currently using 1.5
Page 9
Cycle 11 Calibration Plan: I
• (O’dea and Gilliland)
– CCD Daily monitoring:
Bias/dark verification at different gains
– SBC Dark current monitoring.
– SBC Fold analysis, anomalous recovery
– SBC flats, CCD internal .at stability
– Internal CTE monitor (EPER, FPR)
– CCD Hot Pixel Annealing
– Photometric stability and contamination monitor
– HST focus monitor (ACS, WFPC2 parallel obs.)
Page 10
Cycle 11 Calibration Plan:II
– Earth flats.
– Geometric distortion check, full field sensitivity, L-flat, external CTE
checks.
– Photometry cross-cal. : WFPC2, SDSS, U,B,V,R,I.
– SBC Photometric cross-cal with STIS
– Polarimetry calibration
– PSF definition and HRC red halo
– Coronographic (CORON1.8 and 3.0) PSF
– Shutter stability verification
– Narrowband filter red-leak check
– Wavelength stability narrowband and ramps
– Photometry for extreme red objects
– Grism/prism checks
– Linearity, gain setting qualification
– Sky flats.
Page 11
Cycle 11 Calibration Plan:III
• Special calibrations – capability definition.
– Ramp observations
- flat field, lambda dependent calibration
– Determination of limiting (high) S/N for repeated observations
– Optical baffling check (bright stars off edge)
– Preflash flat field check
– Scattered Earthshine (near limb)
– SBC prisms, brief characterization
– Field dependence of polarimetry.
Page 12
NICMOS
Cooling System Status
Larry Petro
April 18, 2002
Summary
O
O
NCC reached
70-K NICMOS
neon control
temperature
NICMOS
NCS
NICMOS
SMOV begins
4/19
April 18, 2002
70 K
TIPS
2 / 10
Significant events
O
CPL - NCC interface temperature lowered (4/4)
®
O
Minimum reservoir temperature -12˚ C (was -10˚ C)
Neon control temperature attained (4/11)
®
Average of NICMOS inlet and outlet temperatures is 70K
®
NCS performance is nominal
N
Measured NICMOS parasitic load is 6.1 W
– In agreement with predictions
– NICMOS MEB is off
N
Average compressor speed is 7075 rps
– 225 rps less than CARD limit
O
N
Neon coolant temperature is stable (~0.02 K r.m.s.)
N
NCS power is 380 W
NCC not idled during battery reconditioning
April 18, 2002
TIPS
3 / 10
Cooldown completed
L. Bergeron
70-K control temperature reached
April 18, 2002
TIPS
4 / 10
NICMOS cooldown
L. Bergeron
Modeled detector temperature is
75 K = 0.5 (T_in + T_out) + 4
Inlet @ 63 K
Outlet @ 78 K
April 18, 2002
TIPS
5 / 10
Cooling Rate
L. Bergeron
Surging stopped
Control established
Compressor @ 7300 rps
April 18, 2002
TIPS
6 / 10
NCC performance
L. Bergeron
Surging ends
Speed limit 7300 rps
Variable
heat load
70-K control reached
April 18, 2002
TIPS
7 / 10
Environmental influences
C. Long
Constant speed,
variable cooling
rate
April 18, 2002
Orbital variations to maintain
constant temperature
TIPS
8 / 10
Neon coolant temperature
stability
C. Long
C. Long
Variation is ~0.02 K r.m.s.
April 18, 2002
TIPS
9 / 10
NCS status & plans
O
NCS performing nominally
O
Recover NICMOS from safe (4/19)
O
®
After completion of 1st battery reconditioning
®
~0.4 W increase in parasitic heat
Measure NICMOS temperature and stability
®
Control tests with Neon circulator loop temperature
and NICMOS mounting cup thermistor
O
Verify temperature setability
O
Select NICMOS operating temperature
April 18, 2002
TIPS
10 / 10
STIS Status Report
Kailash C. Sahu
Apr 18, 2002
TIPS
OUTLINE
STIS Time Dependent Sensitivity Correction
Sensitivities after SM3B
Echelle Blaze Shift Correction
Improved NUV-MAMA Darks
Phase-II Proposal Reviews
Time Dependent Sensitivity Correction
Symptoms
STIS sensitivities are found to
slowly change with time
Change is as much as 10% in
the last 5 years for some
modes
This depends on the detector,
and also has a wavelength
dependence
The change is not always
monotonic in time
Changes in L and M-modes are
similar
Time Dependent Sensitivity Correction
Correction
Time dependence can be
corrected by applying a
wavelength dependent
correction in linear segments
of time ( Stys and Walborn).
Algorithm developed by
Busko, Hodge, Sahu, Valenti
(and the pipeline group)
Implemented in CALSTIS and
tested
Residual less than ~2%
Ready to be implemented in
the pipeline calibrations.
Time Dependent Sensitivity Correction
4/14/2002
4/16/200
2
4/16/2002
Sensitivities after SM3B
OBSERVATIONS
Sensitivity measurements were taken on April 3 for G230LB, G430L
and G750L modes (CCD modes)
On April 14 and April 16 for G140L
On April 16 for G230L
RESULTS
G140L: 1.8% higher on 14th April, but 0.3% higher on 16th April
G230L: Consistent with extrapolated sensitivity.
G750L: -0.6 ± 1.0% (compared to a single measurement 6 months
earlier)
G430L: +0.1 ± 1.0%
G230LB: -0.8 ± 1.0%
SUMMARY
All measurements are consistent with the expectations.
Echelle Blaze Shift Correction
Echelle Blaze Shift Correction
Symptoms
Redundant flux information at ends of echelle orders
Flux discrepancies as large as 10% (see example)
Flux errors correlate with time and monthly offset in X
Grating angle affects wavelength and blaze differently
First Order Correction
Algorithm developed by Don Lindler (calibration outsourcing)
Measured blaze shifts for 600+ datasets (primary cenwaves)
Linear fit of blaze shift vs. time and offsets in X and Y
Fit coefficients added to new columns in _pht reference file
Calstis enhanced by Ivo Busko; tested by Jeff Valenti
Blaze shift estimated from coefficients; good but not perfect
Data may be reprocessed by hand using arbitrary blaze shift
Still need to add support for secondary wavelength settings
Improved NUV-MAMA Darks
Changes in the mean
operating temperature of
the NUV-MAMA causes dark
current to deviate from the
scaling law used.
Time and temperature
dependent correction
algorithm was developed by
Charles Proffitt
Implemented in CALSTIS
with an option to scale the
dark to a user-input value
(Busko)
Ready to be implemented
in the pipeline
Phase-II Proposal Reviews
Instrument review of ~2/3rd of the proposals have been
completed.
A majority of the remaining are due to PI input, and TOO
proposals which cannot be reviewed at this moment.
There are > 500 snapshot observations with MAMA (many of
which are for imaging). BOP checking of these observations
are time-consuming, and will clearly need more time for
completion of the review.
SPACE TELESCOPE SCIENCE INSTITUTE
TIPS
18 April 2002
Russell Makidon
Monitoring HST Focus in Y2002
• Last Secondary Mirror Move on 2000.197 (+3.5 µm); previous secondary mirror move on 2000.009 (+4.2 µm)
• WFPC2 program 8829 (PI: Gilliland) enacted in late June 2000 to monitor
HST focus at monthly intervals, supplementing existing WFPC2 focus checks.
– 14 orbit program with STIS images obtained in OII and OIII filters in parallel with
some WFCP2 observations.
– program completed in July 2001 with no significant focus excursions noted.
• WFPC2 program 9258 (PI: Gilliland) enabled in July 2001 to continue focus
monitoring started with 8829.
1
2
TIPS
SPACE TELESCOPE SCIENCE INSTITUTE
18 April 2002
Russell Makidon
(no breathing correction applied)
focus
in microns @@
secondary
Focus in
microns
Secondary
Focus Measurements Since Last Mirror Move (2000.197)
(no breathing correction)
SM3b
WFPC2 9258 Focus
WFPC2 8829 Focus
460
440
420
400
380
360
340
320
300
280
260
240
220
200
180
DOY 2001
160
140
120
100
80
60
40
20
0
-20
-40
-60
-80
-100
-120
-140
-160
-180
-200
8
7
6
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
-10
-11
-12
3
TIPS
SPACE TELESCOPE SCIENCE INSTITUTE
18 April 2002
Russell Makidon
focus
in microns @@
secondary
Focus
in
microns
Secondary
(breathing corrected unless otherwise noted)
Focus Measurements Since Last Mirror Move (2000.197)
(breathing correction applied)
SM3b
WFPC2 9258 Focus
WFPC2 8829 Focus
460
440
420
400
380
360
340
320
300
280
260
240
220
200
180
DOY 2001
160
140
120
100
80
60
40
20
0
-20
-40
-60
-80
-100
-120
-140
-160
-180
-200
8
7
6
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
-10
-11
-12
SPACE TELESCOPE SCIENCE INSTITUTE
TIPS
18 April 2002
Russell Makidon
Monitoring HST Focus in Y2002
• No apparent trending with HST focus through from 2000.197 through SM3b.
– The few excursions from ‘nominal’ focus during this period can be explained by
breathing-induced variations.
• During periods of larger than normal temperature variations in OTA, the
breathing model tends to underestimate the extent of focus excursions.
– Observations noted as part of programs 8829 and 9258 with observed focus variations within an orbit as large as 10 µm!
– Breathing-induced focus excursions might be a concern for ACS HRC
observations...
4
SPACE TELESCOPE SCIENCE INSTITUTE
TIPS
18 April 2002
Russell Makidon
Monitoring HST Focus in Y2002
• Post-SM3b Observations showed variability in focus measurements not unlike
those experienced in programs 8829 and 9258
– long periods of atypical HST pointing attitudes led to large excursions of HST focus
from nominal.
5
SPACE TELESCOPE SCIENCE INSTITUTE
6
TIPS
18 April 2002
Russell Makidon
Focus Measurements Since Last Mirror Move (2000.197)
(data since SM3b, no breathing correction)
8
7
6
5
4
focus in microns @ secondary
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
WFPC2 9258 Focus
WFPC2 9574 Focus
-10
-11
-12
459
458
457
456
455
454
453
452
451
450
449
448
447
DOY 2001
SPACE TELESCOPE SCIENCE INSTITUTE
7
TIPS
18 April 2002
Russell Makidon
Focus Measurements Since Last Mirror Move (2000.197)
(data since SM3b, breathing correction applied)
8
7
6
5
4
focus in microns @ secondary
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
WFPC2 9258 Focus
WFPC2 9574 Focus
-10
-11
-12
459
458
457
456
455
454
453
452
451
450
449
448
447
DOY 2001
SPACE TELESCOPE SCIENCE INSTITUTE
TIPS
18 April 2002
Russell Makidon
Monitoring HST Focus in Y2002
• Current Status: Nominal
– Little to suggest a secondary mirror move is warranted at this time
8
SPACE TELESCOPE SCIENCE INSTITUTE
TIPS
18 April 2002
Russell Makidon
Monitoring HST Focus in Y2002
• ACS HRC and WFC now confocal with WFPC2 (PC1)
• Upcoming Events:
– Eleventh set of WFPC2 9258 observations scheduled for period between
29 Apr 2002 (2002.119) and 05 May 2002 (2002.125).
• To be considered...
– Field Dependence of focus over ACS WFC and HRC
– Should secondary position be biased (on ACS) to better center focus distribution
function to zero?
9
SPACE TELESCOPE SCIENCE INSTITUTE
TIPS
18 April 2002
Russell Makidon
Oh, the places we’ve come...
HST focus trend over mission life
Notable focus-related events in
HST Mission Lifetime
150
1
1. First WF/PC Focus Monitoring
100
2. First SM and start of WFPC2 focus
monitoring
3. Breathing Model Enabled
2
50
4. Second Servicing Mission
3
4
5. Servicing Mission 3a
5
6
0
-1000
0
1000
Days since Jan 1, 1994
2000
3000
6. Servicing Mission 3b
Figure courtesy of Matt Lallo
10
MEMORANDUM
TO:
Distribution
DATE:
18 April 2002
SUBJECT:
Questions and Answers from 18 April 2002 TIPS Meeting
HOD Perspective
Presenter – Dave Soderblom
A discussion on the scheduling constraints presented by the Cycle 11 Large and Treasury programs
Q: Does the figure (showing an 11-orbit schedulability per day) mean a large number of orbits in Cycle11
won’t be used?
A: No. The plot only shows the Treasury and GO programs. It doesn’t include SNAPS, carryovers from
other cycles, Targets of Opportunity, etc.
Q: What are you going to say to successful ACS Pure Parallel observers? What about adjustments to RPS2
to help alleviate any problems?
A: There’s ample time and opportunity to work out any issues with ACS Pure Parallel Observers. The
nominal start to Cycle 11 is still months away.
Comment: The Archive has put together a set of guidelines for Treasury program observers to contribute
their data back into the HST Archive. More information on that will be forthcoming.
ACS Status
Presenter – Mark Clampin
A general presentation on the current status of the Advanced Camera for Surveys, including issues of
geometric distortion, etc.
Q: Will STScI have an opportunity to see the ERO images before the Press Conference on 30 April?
A: There are plans to have a presentation for the STScI staff just before the Press Conference.
Q: Is the 24-hour on-time for the Low Voltage Power Supply a one-time event?
A: Yes. Ball believes there should be no need to worry about outgassing from the low voltage electronics
after this 24-hour on-time has passed.
Q: Does the simulated coronographic image (in F435W) take into account the misalignment in the
“Fastie” finger?
A: No. The Fastie finger is not included as part of these simulations.
Q: On the issue of optical baffling… will you do observations with bright targets in the gap between
WFC1 and WFC2?
A: Yes. We believe this will happen as a matter of course, so we don’t have any specific plans to test this
right now.
1
Q: What about the issue of the geometric distortion? There is an outsourced GO program to do the
distortion calibration. Are you going to share your data from the early ACS observations with this GO?
A: Yes, there are plans to offer these data to Ivan King, once the ERO observations have been made
public.
NICMOS Cooling System Status
Presenter – Larry Petro
A discussion on the current status of the NICMOS Cooling System, and plans for the next couple of weeks.
Q: Was the NCS sensitivity to temperatures in the Aft Shroud and HST pointing excursions expected?
A: It was expected that there would be some variation, but not to the extent which has been noted.
STIS Status Report
Presenter – Kailash Sahu
A discussion on the current status of STIS following SM3b.
Q: With respect to the > 500 MAMA SNAP targets… wasn’t there a limit of 100 MAMA SNAP
observations set in the Cycle 11 Call for Proposals?
A: Well, yes… this is true for MAMA imaging. However, there was a lot of “leakage” from spectroscopic
SNAP proposals that made it through the TAC. It’s clear this will be an issue for Cycle 12.
HST Focus Monitoring
Presenter – Russell Makidon
A discussion on the current status of the HST Focus Monitoring Campaign.
Q: Is there any predictive capabilities to the Breathing Model? For example, can a GO predict from the
SMS what level of breathing might be expected for their observations?
A: I believe there is a dependence on HST attitude in the Breathing Model, but not any sort of predictive
capability.
2