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KCWI on-sky commissioning plan1 Background and OverviewThe KCWI commissioning plan includes relevant tests from on-sky commissioning plans drafted by Keck Staff and instrument development teams of previous Keck instruments so that the new hardware and software functionality are well tested and characterized. This document is expected to undergo periodic revision up through the commissioning period for KCWI.

To ensure that the necessary tasks are executed and that the relevant information is reported each task will have an assigned task leader. Task leaders are responsible for the test plan, execution, reduction, and analysis of the acquired data, and although they may enlist others to complete the task, they will ensure that the tasks are completed and reported on reasonable timescales.

Observers will be at the telescope acquiring data and running the tests. It is the responsibility of the task leader to ensure that task descriptions clearly identify all the necessary steps to acquire the data. Observers will work with task leaders by reviewing the observing plans for accuracy, completeness, and clarity.

Data Reducers will reduce and analyze the data and will contribute relevant information in test reports. The analysis of some tasks is completed during the observations, but the analysis of other tasks (e.g. zero points) is longer term, and for these tasks, it is important to identify who is responsible for analyzing and reporting these results.

This document is based on a spreadsheet available on the Keck KCWI documentation page. On that spreadsheet, each task is assigned a priority and an order of execution. The individual tasks are identified by task ID. The same task ID appears here.

2 TasksTitle: Determine guider gross pointing and preliminary

focusTask ID: 1 Priority: HDepends on:Run: 1Lead: Luca, Shui Other involved:Sky time required:

20 Sky conditions: Moderate

Slicer GratingFilter MaskPolarizerOther requirements

Purpose: Verify the gross pointing of a target after absolute pointing of the telescope

Requirements: Reference pointing origin, REF, or similar, defined Pointing origin in guider pixel coordinates defined Plate scale of guider camera defined Orientation and flip of guider camera defined or estimated

Observing plan: Set rotator physical angle 0, stationary mode. Set exposure time to 1s. A short exposure time makes the rastering faster. Set the CA=0, CE=0, previously known goo values, or expected estimated values. Slew to a 6th magnitude star near AZ=0, EL=50. This star will produce diffraction spikes.

Following the spikes will lead to the star. Because of the brightness, it will be easy to identify.

If the star does not appears on the guider image, change CA/CE in a spiral pattern with step size equals to one third of the image size. For example, if image size is 3x3 arcmin, then step size should be 1 arcmin.

Stop the spiral search if CA and CE are greater than 200 arcsec in positive and negative direction.

Revert to original CA/CE values. Set primary mirror focus mode 1000 um and start spiral search again with step size 90

arcsec. Stop the spiral search if CA and CE are greater than 600 arcsc in positive and negative

direction.

Slew to an open cluster, the guider image should show some stars. Slowly move forward the center of the cluster where the density of the stars is the highest. Record the CA/CE values and repeat this procedure using these new CA/CE values as initial point.

If the star still cannot be found at this point, verify the tertiary mirror position and the secondary mirror position and that the dome is not vignetting the view.

Once the first star is found, if possible adjust pointing and mar collimation to record the CA/CE values. If adjust pointing is not possible because the guider camera orientation is not yet accurate, use hand paddle in CA/CE coordinates to move the star to the REF pixel and then mark collimation.

Search the star catalog for 5 different near-by stars of magnitude between 8th and 11th and slew to their coordinates to verify pointing.

Determine guider image orientation and repeat this procedure.Reduction plan: N/A

Deliverables/Completion verification: The star appears near the center of the field of view of the guider

Title: Determine guider orientationTask ID: 40 Priority: HDepends on: 1Run: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: The test determines the angle of the guider image X/Y coordinates relative to the Xim/Yim coordinates.

Requirements: Rotator physical angle zero point defined or estimated Plate scale of guider image defined TV angle defined or estimated

Observing plan: Set rotator physical angle 0, and stationary mode. Slew to mount coordinates AZ=0, EL=50. Start guider camera exposures and set exposure time to 2s. Adjust

according on brightness of stars such that star trails can be seen on the guider image, see example below.

The angle between the star trails and the horizontal axis is the guider image angle, TV angle modulus 180 deg.

Verify that the star trails agree with the MAGIQ compass roses. Slew telescope in mount coordinates to AZ=180 and EL=50 and repeat

the exposures. The average of the two angles for AZ=0 and AZ=180 is a better

estimate of the TV angle. The value of TV angle includes the error of the rotator physical angle,

which must be corrected with ROTBASE. By determining TV angle at AZ=0 and AZ=180, the rotator zero point error is cancelled out. The half the difference of the two angles at AZ= and AZ=180 is ROTBASE.

Once the TV angle is determined, update MAGIQ and DCS/TCS configuration files and restart MAGIQ.

Title: Determine guider handednessTask ID: 2 Priority: HDepends on: 1Run: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: Guider camera flip determines the handiness of the guider camera coordinate system

Requirements:Guider camera orientation, TV angle, definedRotator zero point defined or estimated

Observing plan: Slew to a start at A=0 and EL=0, 10th magnitude. Set rotator angle to 0 deg and stationary mode. Start guider exposures. MAGIQ compass roses, East/North and AZ/EL, are approximately

aligned depending on how well TV angle and rotator zero point are defined.

For each of the following coordinates systems RA/DEC coordinates, AZ/EL coordinates, and TV X/Y pixel coordinates

perform offsets on each axis in positive and negative direction and verify that the motion and the direction match the direction of the compass roses. Adjust TV angle and TV flip accordingly in configuration files and

restart MAGIQ. There is also an additional image flip flag that is only in the MAGIQ

configuration. This flag depends on the focal station, on the number of reflections and how the image is read out.

Reduction plan:

Deliverables/Completion verification: TVFLIP and TVANGL are correctly set, and saved on the corresponding configuration files. The star moves in the correct way on the guider when telescope moves are issued.

Title: Determine REF pointing originTask ID: 3 Priority: HDepends on: Guider working and calibratedRun: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: Establish the fundamental pointing origin REF, which is usually the center of the guider

Observing plan: 1- Slew to a bright star at high elevation, get a handpaddel in Xim,Yim coords, PA = 0, Rotator in stationary mode2- Center the star on the guider, measure the centroid (x1, y1)3- Rotate 180 degrees4- Measure centroid (x2, y2)5- calculate the mid point between (x1,y1) and (x2,y2), move the star to the new center with handpaddle6- repeat if necessary. Set as REF

Reduction plan:

Deliverables/Completion verification: REF pointing origin is determined and saved to the configuration database for TCSU. A star on the guider ends on the center of the guider if it is “sent to REF”.

Title: Determine other KCWI pointing originsTask ID: 4 Priority: HDepends on: Guider working, REF definedRun: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: Make sure that all the necessary KCWI pointing origins are defined. The list of pointing origins is:REF: Center of the guiderFPC: Center of the focal plane cameraSLS: Center of the middle slice of the small slicer (Optional)SLM: Center of the middle slice of the medium slicer (Optional)SLL: Center of the middle slice of the large slicer (Optional)

Observing plan: Questions to be solved before we can come up with an observing plan: 1- Do we need separate pointing origins for each of the IFU or are

they aligned with sufficient precision?We need separate PO for each slicer. The precision is sufficient but they are aligned at the edge between two slices, not at their center

2- Do we need separate pointing origins for each slice of a given IFU?No. We can use scripts

If possible, it would probably make sense to have just one PO and then have scripts that automatically offset the telescope to each slice if the observer requires the object to be on a particular position.

Reduction plan:

Deliverables/Completion verification: The necessary pointing origins from the list above are defined. A star sent to those origins ends up at the right coordinates

Title: Guiding in PA mode (sidereal) at different PAsTask ID: 5 Priority: HDepends on: Guider working properly, rotatorRun: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: Main guiding mode. We want to verify that we can guide at different values of the PA

Observing plan: 1- Slew to bright high elevation star2- Set PA=0, start guiding3- Save focal plane camera image4- Guide for 5 minutes5- Save focal plane camera image for comparison6- Repeat for other PAs as desired

Reduction plan:Compare initial and final focal plane images, verify that the star motion is within acceptable tolerance

Deliverables/Completion verification: The guider can guide at all PA values. The motion is within the acceptable tolerance (what is the tolerance?)

Title: Guiding in PA in non-sidereal modeTask ID: 6 Priority: LDepends on:Run: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: Verify that we can guide in non-sidereal mode

Observing plan: 1- Slew to non-sidereal target2- Set PA=0, start guiding3- Verify that the target maintains the position

Reduction plan:

Deliverables/Completion verification: The guider can guide in non-sidereal mode

Title: Measure guider plate scale and astrometryTask ID: 7 Priority: HDepends on:Run: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: Verify the plate scale of the guider and compare with the expected values

Observing plan: 1- Slew to dense field2- Acquire image3- Analyze offline

Reduction plan: Shui has a program to do this, almost in real time.

Deliverables/Completion verification:

Title: Measure performance of guider on large offsetsTask ID: 8 Priority: MDepends on: Guider astrometryRun: 2Lead: Luca, Shui Other involved:Sky time required:



Purpose: If the high order distortion terms are correct, large offsets are accurate

Observing plan: TBD

Reduction plan:


Title: Focus the guiderTask ID: 9 Priority: LDepends on:Run: 3Lead: Luca, Shui Other involved:Sky time required:



Purpose: Test the guider focus procedure

Observing plan: 1. slew to bright star, center at REF2. start the guider focus procedure

Reduction plan:

Deliverables/Completion verification: The guider can be focused. Estimate of the required time to complete the procedure.

Title: Focal Plane Camera Verification and Preliminary Characterization

Task ID: 10 Priority: HDepends on: 5 (Guiding in PA mode at REF)

Run: 1 (Possible in late evening twilight)Lead: Matt Other involved: WMKOSky time required:

30 minutes Sky conditions: Moderate

Purpose: Acquire image of near-overhead star on the focal plane camera to verify functionality and image display. Get an on-sky handle of the camera response with and without the CAL ND filter in the beam. *Note: This task, along with task 25 might be useful to perform before determining the pointing origin for the slicers (Task 4) or general pointing acquisition (Task 10). A live feedback of telescope moves should be more efficient than waiting on science CCD readout. We will have a fairly good idea of the relative location of the center of the FPC and the slicers from calibration activities (Task 27)

Slicer FPC Grating N/AFilter None/Cal-ND Mask N/APolarizer OutOther requirements

Observing plan: 1. Telescope in PA mode, Image de-rotator at PA=0°2. Slew to a high elevation star (B=TBD) near the slicer PO, use this star

for guiding(If doing this before KCWI POs are established, may need to manually command offsets to land the star on the focal plane camera. Record this offset, once done)

3. Make sure CAL ND filter is retracted4. Take a short exposures (t = TBD)5. Verify that the images are being displayed properly on the ds9 window 6. Make sure images are not saturated, slew to a dimmer nearby star if

so, repeat7. Take a series of images and a stack of images8. Insert CAL ND filter, verify telescope does not lose tracking9. Take a longer exposure (t=TBD)10. Take a series of images and a stack of images

11. Verify image display in ds9 and approximate reduction in flux12. Retract CAL ND filter

Reduction plan: Inspect saved images offline, verify ND filter acts as expected. Compute rough sensitivity. Deliverables/Completion verification: A first pass estimate of the camera throughput and refined (but still not final) B-mag to exposure time calculator for FPC with and without the ND filter.

Title: FPC Handedness and Plate ScaleTask ID: 11 Priority: MDepends on: 5 (Guiding in PA mode)

7 (Guider plate scale and astrometry)10 (FPC Verification and Prelim Characterization)

Run: 2 (though 1 might be better)Lead: Matt Other involved: WMKOSky time required:


Purpose: Measure the plate scale and handedness of the focal plane camera

Slicer FPC Grating N/AFilter None/CAL-ND Mask N/APolarizer OutOther requirements

Requirements: Guider angle and flip defined Rotation zero point defined Instrument angle defined or estimated A pointing origin within the field of view of the instrument

Observing plan: Slew to a star, 10th to 11th magnitude and center on REF. Change to the instrument pointing origin. Put PMFM = 300um or greater depending on the plate scale of the

instrument detector. Take an image. Find the segments #22, #9, #2, #5, #15 and #31. They are aligned

with the vertical axis. Segment #22 points to lower elevation and #31 points to higher

elevation. Calculate the centroids of the said segments. The centroids must lie on a line. The angle between this line and the columns of the detector is the

instrument angle. Depending on the flip of the image, the angle can be the 180 deg complement.

Reduction plan: Analyze the images offline (S. Kwok’s software) Centroid the star in each image compute plate scale and refine tkrose.

Deliverables/Completion verification: Refined tkrose and FPC plate scale

Title: FPC Limiting MagnitudeTask ID: 12 Priority: LDepends on: 5 (Guiding in PA mode)

11 (FPC Handedness and plate scale)Run: 2Lead: Matt Other involved: WMKOSky time required:

30 Sky conditions: Clear

Purpose: Determine the limiting B magnitude of the Focal Plane Camera for a SNR of 5 in 30 seconds. The FPC field of view is small 18 x 16 arc seconds unvignetted.

Slicer FPC Grating N/AFilter None/CAL-ND Mask N/APolarizer OutOther requirements

Observing plan: Option 1:

1. Telescope in PA mode with suitable PA angle2. Slew to a dense star field (TBD)3. Take a short (1 s) exposure to estimate time T to saturation4. Take a series of T length exposures to add up to 30 s, repeat. Save all

imagesOption 2:

1. Telescope in PA mode with PA=0°2. Slew to a series of high elevation stars from B=18 in dB ~ 1

increments, preferably of the same or very similar spectral typea. Take a series of t = 1 s images for each star, save imagesb. With a single star in view, use a script to quickly determine the

acquired SNR. Script could (should?) generate exposure times for dimmer stars

c. Be flexible in magnitude increments, skip steps if SNR high to converge on limiting magnitude as quickly as possible

d. Once limiting magnitude found, confirm with object of similar brightness

Reduction plan: Option 1:

Reduce offline using standard astronomical tools (SExtractor) and a deep star catalog (e.g., USNO B 2.0). Option 2:

Use script to compute magnitudes (verify later offline). Need to write script.

Deliverables/Completion verification:Limiting magnitude of the FPC for a point source in a 30 s exposure. Exposure T calculator?

Title: FPC astrometric solutionTask ID: 13 Priority: LDepends on: 5 (Guiding in PA mode)Run: 2Lead: Matuszewski Other involved: WMKOSky time required:



Purpose: Find the astrometric solution for the focal plane camera. Note, that the focal plane camera has a very small field of view (comparable to the medium KCWI slicer, or 15 x 20 arc seconds). As such, the expected distortions are not anticipated to be particularly large.

Observing plan: 1. Telescope in PA mode with suitable PA angle2. Ensure FPC images are being saved3. Slew to desired dense star field with 10 -20 stars in the FOV and start

guiding4. Take a short FPC image to establish suitable exposure time, t5. Take a series of longer exposure times to build up good SNR (>5) in

the majority of visible stars

Reduction plan: Reduce data offline using standard astronomical tools

Deliverables/Completion verification: Astrometric solution for FPC (quaternion? WCS?)

Title: Acquire images for MIRA calibrationTask ID: 14 Priority: LDepends on:Run: 1 or 2Lead: Luca, Shui Other involved: WMKOSky time required:



Purpose: Take images with FPC at different PMFM modes to determine rotation and handedness of images for MIRA analysis.

Observing plan: 1. Slew to MIRA star at an elevation of 70 and hour angle 2 hours east2. Center the star on the FPC 3. Apply 250 nm of PMFM4. Acquire FPC image, verify exposure5. Kick out a segment, acquire second image

Reduction plan: Shui to analyze in real time and make corrections to MIRA script if necessary. This is an update done in real time.

Deliverables/Completion verification: MIRA images are characterized in position and rotation angle.

Title: Verify that MIRA script works and correctly measures FOCUS

Task ID: 15 Priority: LDepends on:Run: 1 or 2Lead: Luca, Shui Other involved: WMKOSky time required:



Purpose: Run the MIRA script and verify it correctly measures focus and tilt (Optional)

Observing plan: 1. Slew to MIRA star at an elevation of 70 and hour angle 2 hours east2. Center the star on the FPC3. Focus the telescope using alternate method (Autofocus) 4. Run MIRA script5. Verify that MIRA requires no focus correction6. Apply piston offset7. Verify that MIRA predicts the piston correction8. Repeat for different values of piston

Reduction plan:

Deliverables/Completion verification: MIRA correctly corrects for piston offsets.

Title: Test AUTOFOCTask ID: 16 Priority: HDepends on: Guider working, and able to trackRun: 1Lead: Luca, Shui Other involved:Sky time required:



Purpose: Autofocus replaces MIRA if MIRA does not work, or if the seeing is too large. Verify that it runs.

Observing plan: 1. Slew to bright star2. Run autofocus procedure3. Compare results with MIRA if available

Reduction plan:

Deliverables/Completion verification: Autofocus works and produces sensible results. The results compare well with MIRA if available.

Title: Object AcquisitionTask ID: 17 Priority: HDepends on: 10Run: 1Lead: Morrissey Other involved:Sky time required:


Slicer FPC Grating OpenFilter Red blocking Mask OpenPolarizerOther requirements

Camera in zeroth order

Purpose: Show that target objects can be positioned in the science field of view. Determine the focus offsets of the FPC and the three image slicers in zero order.

Observing plan: This task is complementary to Task 11, KCWI Pointing Origins.

1. Insert the focal plane camera (FPC) in the field2. Align the science camera for zero order imaging3. Remove the N&S mask4. Insert the red blocking filter5. Remove the grating6. Verify the spectrograph is in focus with a flat field calibration arc lamp

image7. Acquire a star (within 1 hour of zenith) in the guider8. Center the star in the guider9. Focus the guider10. Begin guiding11. Download a FPC image, verify properly exposed star image12. Capture FPC images at different telescope focus positions13. Refocus the guider at the FPC focus position14. Verify star image is in a location that will be captured by all 3

slicers15. Offset star in guider field if necessary16. Insert the large IFU slicer17. Download an image, verify properly exposed star image18. Focus the telescope of the large slicer19. Repeat for the medium and small slicers.

Reduction plan: Offline? The reduction plan would be to use a modified form of CWI_Center_Star on the raw KCWI images to determine offsets from the slicer origins. Images can be examined in ds9 to determine best focus.

Deliverables/Completion verification: The guider images, pointing offsets, focus offsets and science images should all be captured. If a star on the guider can be successfully offset and focused for each IFU and the Focal Plane Camera, then the task is complete

Title: Spectrum AcquisitionTask ID: 18 Priority: HDepends on: 11, 17Run: 1Lead: Morrissey Other involved:Sky time required:

180 Sky conditions: Thin clouds ok

Slicer GratingFilter MaskPolarizerOther requirementsPurpose: The purpose of this task is show that the instrument properly acquires seeing-limited spectra. It is complementary to Task 18.

Observing plan: To the extent that standard stars can be observed, this task overlaps Task 34.

1. Insert the large slicer in the field2. Remove the N&S mask3. Insert the red blocking filter4. Insert the BH3 grating5. Configure for Hbeta observations6. Verify the spectrograph is in focus with a flat field calibration arc

lamp image7. Acquire a star (within 1 hour of zenith) in the guider8. Center the star in the guider (presuming no offset is required for

any slicer)9. Focus the guider10. Begin guiding11. Download an image, verify properly exposed star image12. Focus the telescope on the large slicer13. Repeat 11-12 for the medium and small slicers.14. Reconfigure for BM grating at Hbeta with the large slicer15. Acquire a flat field calibration arc lamp image to verify

spectrograph focus16. Determine best telescope focus for the BM grating17. Repeat 14-16 for the medium and small slicers18. Reconfigure for BL grating at Hbeta with the large slicer19. Acquire a flat field calibration arc lamp image to verify

spectrograph focus20. Determine best telescope focus for the BL grating21. Repeat 18-20 for the medium and small slicers

Reduction plan: We will be able to determine best focus from visual analysis of the data at the telescope, but more detailed analysis offline may be desired for the final result. It should be possible to use the focus offsets determined in Task 33 rather than refocusing each slicer/grating combination. It depends on how stable to telescope focus is and whether there is a benefit to refocusing to provide confidence in the measured spatial resolution.

Deliverables/Completion verification: The Hbeta spectrograph focus should be recorded for each grating and slicer combination. Assuming 10 images are required for each focus curve, there will be 90 images and 9 instrument configurations required to complete this task. The task is complete when seeing-limited spectra have been acquired in all modes.

Title: Test spectral throughputTask ID: 19 Priority: MDepends on: 18Run: 2Lead: Morrissey Other involved:Sky time required:

Sky conditions:


Purpose: Spectrophotometric standards will be used to determine the total throughput of the instrument (and telescope and sky).

Observing plan:1. Insert the large slicer in the field2. Remove the N&S mask3. Insert the red blocking filter4. Insert the BH3 grating5. Acquire a standard star (within 1 hour of zenith) in the guider6. Center the star in the guider (presuming no offset is required for

any slicer)7. Focus the guider (presuming the guider focus has been chosen to

be confocal with the science focal plane)8. Begin guiding9. Configure for Hbeta observations10. Verify the spectrograph is in focus with a flat field calibration arc

lamp image11. Download an image, verify properly exposed star image12. Repeat 10-11 for the medium and small slicers.13. Reconfigure for BM grating at Hbeta with the large slicer14. Acquire a flat field calibration arc lamp image to verify

spectrograph focus15. Repeat 13-14 for the medium and small slicers16. Reconfigure for BL grating at Hbeta with the large slicer17. Acquire a flat field calibration arc lamp image to verify

spectrograph focus18. Repeat 16-17 for the medium and small slicers19. As time permits, the camera/grating may be configured to other

wavelengths to capture the full range of BL, BM and BH with at least one slicer.

Reduction plan: Reduction will be offline using the pipeline and probably one independent method for verification.

Deliverables/Completion verification: The effective area of the system in each mode should be documented in a report with an attempt to back out the efficiency of the instrument alone.

Title: Test Spectral Throughput of all SlicesTask ID: 20 Priority: LDepends on: 19Run: 2Lead: Morrissey Other involved:Sky time required:

Twilight Sky conditions: Thin clouds


Purpose: Measure the relative throughput across the science field of view

Observing plan: The plan is to measure the flat field of the instrument using illumination from the sky, and to scale this to the measured standard star efficiency. For the purposes of generating a high signal-to-noise flat field, twilight illumination will be useful.

1. Insert the large slicer in the field2. Remove the N&S mask3. Insert the red blocking filter4. Insert the BH3 grating5. Point telescope to the zenith during twilight6. Configure for Hbeta observations7. Verify the spectrograph is in focus with a flat field calibration arc

lamp image8. Download an image, verify properly exposed star image9. Record enough images to create a high S/N flat (~1%)10. Repeat 6-9 for the medium and small slicers.11. Reconfigure for BM grating at Hbeta with the large slicer12. Acquire a flat field calibration arc lamp image to verify

spectrograph focus13. Record enough images to create a high S/N flat (~1%)14. Repeat 11-13 for the medium and small slicers15. Reconfigure for BL grating at Hbeta with the large slicer16. Acquire a flat field calibration arc lamp image to verify

spectrograph focus17. Record enough images to create a high S/N flat (~1%)18. Repeat 15-17 for the medium and small slicers

19. As time permits, the camera/grating may be configured to other wavelengths to capture the full range of BL, BM and BH with at least one slicer.

Reduction plan: Data will be reduced offline using a combination of the pipeline and custom software.

Deliverables/Completion verification: The absolute throughput as a function of wavelength for each configuration and position (flat field vs wavelength) should be available to observers to aid in the reduction of their data.

Title: Determine Rotator Zero pointTask ID: 21 Priority: HDepends on: 1Run: 1Lead: Morrissey Other involved:Sky time required:

60 Sky conditions: Thin clouds


Purpose: The rotator zero point is the offset of the rotator physical angle such that when rotator physical angle is zero the rotator is aligned with the vertical axis. This procedure should be used only after TV angle is determined

Requirements:TV angle is defined

Observing plan: Method 1Set rotator physical angle to TV angle, and stationary mode.Slew to mount coordinates AZ=0, EL=50.Start guider camera exposures and set exposure time to 2s. Adjust according on brightness of stars such that star trails can be seen on the guider image.The angle between the star trails and the horizontal axis is the rotator zero point.Repeat with AZ=180, the resulting angle should the same of the angle obtained with AZ=0 but with opposite sign.Update ROTBASE in DCS/TCS configuration and reselect instrument. Method 2Slew to an open cluster with at least 3 stars.Take a guider image.Compare guider image with a DSS image overlaid with stars from a standard catalog.Match the visible stars in the guider image and from the star catalog and calculate the rotation angle. The angle is the rotation zero point.Repeat at different pointing locations and average the calculated angles.

Update ROTBASE in DCS/TCS configuration and reselect instrument.

Reduction plan: Software written by S. Kwok


Title: Determine Rotator LinearityTask ID: 22 Priority: HDepends on: 1Run: 1Lead: Morrissey Other involved:Sky time required:

60 Sky conditions: Thin clouds


Purpose: Verify correct tracking of the guider

Observing plan: The idea is to acquire star trails at 0, 90, 180, 270 in stationary mode and verify that the stellar tracks are parallel or perpendicular to the CCD reference axis

Reduction plan:


Title: Measure the effect of scattered lightTask ID: 25 Priority: MDepends on:Run: EngLead: Luca, Shui Other involved:Sky time required:

60 Sky conditions: Clear


Purpose: Measure the effect of moon light contamination

Observing plan: 1. Slew to selected position near the moon2. Acquire spectrum3. Slew to next position (repeat at 5,10,15,20, 30 degrees away)4. Acquire spectrum

Reduction plan: Full pipeline reduction

Deliverables/Completion verification: The produce is a table of sky background contribution as a function of moon distance, and a recommendation to the users as to how close to observe to the moon.

Title: Test Rehearsing Phase of N&STask ID: 26 Priority: HDepends on: 1-7, 21, N&S planning test or hand-made scriptRun: 1Lead: Don Other involved: Matt, Shui, LucaSky time required:


Slicer Large Grating BH2Filter BLUE Mask InPolarizer OutOther requirements

Save Guider Imgs

Purpose: Verify the correct functioning of the N&S rehearsal phase.

Pre-observing plan:1. Pick a nearby galaxy with obvious emission features.2. Set exposure time such that observation will produce high S/N

imaging.3. Pick a blank background field with no point sources.4. Generate finder charts for two fields for verification.5. Generate script with N&S planning tool or by hand.

Observing plan:1. Run N&S execution tool.2. Load script and set to rehearsal mode in GUI.3. Acquire science field4. Verify science field and guide star coordinates.5. Begin guiding.6. Initiate rehearsal move to background.7. Verify background field and guide star coordinates.8. Save script with guide star adjustments.9. Complete rehearsal mode.10. Verify return to science field with guiding on.11. Verify updates to script.

Reduction plan: None.

Deliverables/Completion verification: Verification of correct functioning of N&S rehearsal mode, initial estimate of rehearsal overhead (time).

Title: Test Execution Phase of N&STask ID: 27 Priority: HDepends on: 26Run: 1Lead: Don Other involved: Matt, Shui, LucaSky time required:


Slicer Large Grating BH2Filter BLUE Mask InPolarizer OutOther requirements

N&S config

Purpose: Verify the correct functioning of the N&S execution phase.

Observing plan:1. After completion of N&S rehearsal phase, initiate execution phase.2. Verify nods with guider display.3. Verify completion of execution and readout of image.4. Verify correct shuffling of charge by display of science image in ds9.5. If time permits, verify pausing and aborting the execution phase.

Reduction plan: Reduce data offline with KDERP. Verify N&S subtraction.

Deliverables/Completion verification: Verification of correct functioning of N&S execution mode and operational procedure for operating the N&S execution script,initial estimate of N&S overhead (time).

Title: Guider differential flexureTask ID: 28 Priority: LDepends on: Guider astrometryRun: EngLead: Luca, Shui Other involved:Sky time required:



Purpose: Not sure this is necessary at this time, as the gravity vector is constant

Observing plan:

Reduction plan:


Title: Verify and Characterize DAR CompensationTask ID: 31 Priority: HDepends on: 5 (Guiding in PA mode)

7 (Guider plate scale and astrometry)Run: 1Lead: Matt, Don Other involved: Shui, LucaSky time required:


Purpose: The MAGIQ guider in the KCWI Blue Channel instrument guides in I band, whereas the instrument observes in U, B, and V. Differential atmospheric refraction will lead to smearing of objects on the science detector. The purpose of this task is to verify that the magnitude and direction of the DAR compensation built into guiding is correct. This can easily be done in bright time and can (probably) be done in nautical twilight or dimmer sky. Slicer Large Grating BLFilter Blue Mask OutPolarizer Out

Observing plan: Sequence 1:

1. Telescope in PA mode2. Slew to a bright (U = TBD) blue star at high airmass (setting z = 2 or

rising z = 3 ) with Dec close to 19.8°3. Set PA to align the dispersion direction (elevation) with the long axis of

a slice4. Offset star to the center of slice 10, configure the DAR tool/software to

compensate and track at 380 nm5. Take science exposures of a few seconds to and adjust exposure time t

to get good SNR6. Take a cadence of exposures as the object rises (sets?) for 40 minutes7. Record MAGIQ guider generated offsets and guider images during this

timeMay need a second sequence to verify compensation angles, or at another slicer orientation? These tests can be quite time consuming, though.

Reduction plan: Reduce data through KCWI pipeline offline. Determine shift of object at different wavelengths within the BM range – making sure that the configured wavelength (380 nm) remains fixed. Do this by looking at

narrowband images from the cube around 380 nm. Verify other wavelengths shifting in appropriate fashion

Deliverables/Completion verification: Verification that the DAR compensation is valid

Title: Verify Polarizer CapabilityTask ID: 32 Priority: MDepends on: 5 (Guiding in PA mode)

12 (FPC Limiting magnitude)19 (Test spectral throughput -- optional)

Run: 2Lead: Matt Other involved: WMKOSky time required:

45 Sky conditions: Thin

Purpose: KCWI is equipped with a linear polarizer that can be inserted into the beam and rotated to an arbitrary angle. Three images of an object, with the polarizer set to 3 different angles, allow for the determination of the amount and direction of the linear polarization of the source. The purpose of this test is to verify this capability and to refine the polarizer offset angle.

Observing plan: 1. Telescope in PA mode with PA=0°2. Instrument configured as follows:

Slicer FPC Grating BLFilter FPC-ND? Mask NoPolarizer Out

3. Slew to a polarimetric standard (LRIS documentation is a good resource:http://www2.keck.hawaii.edu/inst/lris/polarimeter/pol_quickref.html)

4. Offset to slicer pointing origin, begin guiding5. Take a series focal plane image of the object (determine exposure time

and save all FPC images)6. Insert polarizer into the beam with and take a series of images with

polarizer at angle P=0°, 120°, 240°. Instrument setting:Slicer FPC Grating BLFilter FPC-ND? Mask NoPolarizer Yes (0°, 120°,

240°)Other requirements

Guiding

7. Repeat steps 2 to 6 for another standard

8. Turn off focal plane camera, insert large slicer:

Slicer Large Grating BLFilter Red-Blocking Mask No

http://www2.keck.hawaii.edu/inst/lris/polarimeter/pol_quickref.html

Polarizer Yes (0°, 120°, 240°)

Other requirements

Guiding

9. Offset object to center on slice 1110. Rotate polarizer to P=0°, 120°, 240° and acquire science image

with good SNR at each setting11. Remember to take a full set of calibrations, including polarizer

flats in the afternoon/morning

Reduction plan: Reduce science data offline through the KDERP. Analyze FPC images offline. Determine fluxes for the three polarization images and combine to deduce the degree of linear polarization and direction. Compare with and calibrate against tabulated values.

Deliverables/Completion verification: Verification of polarizer capability and refinement of polarizer 0 angle.

Title: Characterize Polarimetry Capability for Faint Objects

Task ID: 33 Priority: MDepends on: 27 (Test execution of Nod-and-Shuffle)

32 (Verify Polarizer Capability)Run: 2Lead: Matuszewski Other involved: Morrissey,

Martin?Sky time required:

130 Sky conditions: Clear, Dark

Purpose: Explore the sensitivity of the KCWI polarimeter to faint diffuse sources. This could be part of the science verification, though in that case the target selected will be dimmer, and required time longer (200 minutes, min).Slicer Large Grating TBDFilter Blue Mask INPolarizer InOther requirements

Observing plan: 1. Prepare a nod-and-shuffle observation for the selected extended object2. Telescope in PA mode, PA angle set to selected target3. Instrument in N+S mode, large slicer, filter, grating TBD4. Slew to known polarized extended/diffuse nebula (TBD)5. Align on target and rehearse N+S script6. Insert polarizer and rotate to P=0°

a. Take a 10+10 minute N+S7. Rotate polarizer to P=120°

a. Take a 10+10 minute N+S8. Rotate polarizer to P=240°

a. Take a 10+10 minute N+S9. Retract polarizer

a. Take a 10+10 minute N+S10. Remember to take appropriate calibrations in the

afternoon/morning

Reduction plan: Offline, using KDERP, same concept as task 32.

Deliverables/Completion verification: Estimate of the sensitivity of polarimetric measurements with KCWI Blue.

Title: Verify direct imaging modeTask ID: 34 Priority: MDepends on: 5 (Guiding in PA mode)Run: 2Lead: Matt Other involved: WMKOSky time required:


Purpose: Verify direct imaging data acquisition and image reconstructionSlicer All Grating OutFilter Blue Mask OutPolarizer OutOther requirements

Observing plan: 1. Telescope in PA mode with PA angle set appropriately for the target

(most likely PA=0° is OK)2. Slew to target (TBD, open cluster, outskirts of a cluster, dense star

field, etc. – want 10 – 20 stars on the large slicer)3. Offset target to slicer pointing origin, start guiding4. Focal plane camera in

a. take short exposure of field with focal plane camera5. Large slicer in

a. take a science exposure of field, short (t = tbd)b. take a science exposure of field, long (t = tbd)

6. Medium slicer ina. take a science exposure of field, short (t = tbd)b. take a science exposure of field, long (t = tbd)

7. Small slicer ina. take a science exposure of field, short (t = tbd)b. take a science exposure of field, long (t = tbd)

Reduction plan: Reduce offline with KDERP. FPC images using standard astronomical image reduction tools.

Deliverables/Completion verification: Confirm direct imaging works, estimate sensitivity from stars in the field.

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