Observing plan

KCWI on-sky commissioning plan

1 Background and Overview

TBD

2 Tasks

Title:

Task ID:

Depends on:

Determine guider gross pointing

1 Priority:

Run:

Lead:

1

Luca, Shui

Sky time required: 20

Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer

Other requirements

Grating

Mask

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

Observing plan: Point the telescope to a bright target near the pole (to minimize telescope and rotator moves), examine the guider images to verify pointing

Reduction plan:

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

Title: Determine guider handedness

Task ID:

Depends on:

2 Priority:

1, depends on rotator calibration

Run: 1

Lead: Luca, Shui


Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer


Grating

Mask

Purpose: Make sure that DCS and Magiq kno the orientation of the guider

Observing plan:

1- Slew to a bright high elevation star

2- Set rotator to PA mode with PA=0

3- Start guiding

4- execute a series of offset commands and take an image at each position

i- en 10 0 (10" east)

ii- en 0 -10 (10" south)

iii- en -10 0 (10" west)

iv- en 0 10 (10" north)

or use the handpaddle to get the same behaviour

6- Adjust TVFLIP and TVANGL in DCS

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 origin

Task ID:

Depends on:

3 Priority:

Guider working and calibrated

Run:

Lead:

1

Luca, Shui


Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer


Grating

Mask

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 mode

2- Center the star on the guider, measure the centroid (x1, y1)

3- Rotate 180 degrees

4- Measure centroid (x2, y2)

5- calculate the mid point between (x1,y1) and (x2,y2), move the star to the new center with handpaddle

6- repeat if necessary. Set as REF

Reduction plan:

Deliverables/Completion verification: REF pointing origin is determined and saved to the configuration file ( PATH!

), a star on the guider ends on the center of the guider if it is “sent to ref”

Title: Determine other KCWI pointing origins

Task ID:

Depends on:

4 Priority:

Guider working, REF defined

Run:

Lead:

1

Luca, Shui


Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer


Grating

Mask

Purpose: Make sure that all the necessary KCWI pointing origins are defined. The list of pointing origins is:

TBD: LIST OF POINTING ORIGINS

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?

2- Do we need separate pointing origins for each slice of a given IFU?

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:

Task ID:

Depends on:

Guiding in PA mode (sidereal) at different PAs

5

Run:

Lead:

1

Luca, Shui


Priority:

Guider working properly, rotator

Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer


Grating

Mask

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

Observing plan:

1- Slew to bright high elevation star

2- Set PA=0, start guiding

3- Save focal plane camera image

4- Guide for 5 minutes

5- Save focal plane camera image for comparison

6- 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 mode

Task ID:

Depends on:

6 Priority:

Run:

Lead:

1

Luca, Shui


Slicer

Other involved:

Sky conditions:

Filter

Polarizer


Grating

Mask

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

Observing plan:

1- Slew to non-sidereal target

2- Set PA=0, start guiding

3- Verify that the target maintains the position

Reduction plan:


The guider can guide in non-sidereal mode

L

Moderate

Title:

Task ID:

Depends on:

7

Measure guider plate scale and astrometry

Priority:

Run:

Lead:

1

Luca, Shui


Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer


Grating

Mask

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

Observing plan:

1- Slew to dense field

2- Acquire image

3- Analyze offline

Reduction plan:


Title:

Task ID:

Depends on:

Measure performance of guider on large offsets

8

Guider astrometry

Run:

Lead:

2

Luca, Shui


Priority:

Other involved:

Sky conditions:

M

Moderate

Slicer

Filter

Polarizer


Grating

Mask

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

Observing plan: TBD

Reduction plan:


Title: Focus the guider

Task ID:

Depends on:

9

Run:

Lead:

3

Luca, Shui


Priority:

Other involved:

Sky conditions:

L

Moderate

Slicer

Filter

Polarizer


Grating

Mask

Purpose: Test the guider focus procedure

Observing plan:

1.

slew to bright star, center at REF

2.

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:

Depends on:

10 Priority:

5 (Guiding in PA mode at REF)

4 (KCWI Pointing origins)*

1 (Possible in late evening twilight) Run:

Lead: Matt

Sky time required: 30 minutes

Other involved:

Sky conditions:

H

WMKO

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 XX) or general pointing acquisition (Task YY). 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

Filter

FPC

None/Cal-ND

Grating

Mask

N/A

N/A

Polarizer


Out

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 retracted

4.

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, repeat

7.

Take a series of images and a stack of images

8.

Insert CAL ND filter, verify telescope does not lose tracking

9.

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 flux

12.

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 Scale

Task ID:

Depends on:

11 Priority: M

5 (Guiding in PA mode)

7 (Guider plate scale and astrometry)

10 (FPC Verification and Prelim Characterization)

2 (though 1 might be better) Run:

Lead: Matt


Other involved:

Sky conditions:

WMKO

Moderate

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

Slicer FPC Grating N/A

Filter

Polarizer

None/CAL-ND

Out

Mask N/A


Observing plan:

1.

Telescope in PA mode. Image de-rotator at PA=0°

2.

Slew to a high elevation star, B=TBD.

3.

Offset star to Slicer or FPC PO

4.

Start guiding

5.

Acquire and save FPC images at a series of positions

(The images should be long enough to average over the seeing; thus they may need to be stacked) a.

at PO b.

en 7 0 (7” east) c.

en 0 -7 (7” south) d.

en -7 0 (7” west) e.

en 0 7 (7” north)

6.

Verify tkrose has approximately the right orientation

Reduction plan: Analyze the images offline. Centroid the star in each image compute plate scale and refine tkrose


Refined tkrose and FPC plate scale

Title: FPC Limiting Magnitude

Task ID:

Depends on:

Run:

12 Priority:


11 (FPC Handedness and plate scale)

2

Lead: Matt


Other involved:

Sky conditions:

L

WMKO

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

Filter

Polarizer


None/CAL-ND

Out

Grating

Mask

N/A

N/A

Observing plan:

Option 1:

1.

Telescope in PA mode with suitable PA angle

2.

Slew to a dense star field (TBD)

3.

Take a short (1 s) exposure to estimate time T to saturation

4.

Take a series of T length exposures to add up to 30 s, repeat. Save all images

Option 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 type a.

Take a series of t = 1 s images for each star, save images b.

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.


Limiting magnitude of the FPC for a point source in a 30 s exposure. Exposure T calculator?

Title: FPC astrometric solution

Task ID:

Depends on:

Run:

Lead:

13


2

Matuszewski


Priority:

Other involved:

Sky conditions:

L

WMKO

Moderate

Slicer

Filter

Polarizer


FPC

None/Cal-ND

Out

Grating

Mask

N/A

N/A

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 angle

2.

Ensure FPC images are being saved

3.

Slew to desired dense star field with 10 -20 stars in the FOV and start guiding

4.

Take a short FPC image to establish suitable exposure time, t

5.

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: Test AUTOFOC

Task ID:

Depends on:

16 Priority:

Guider working, and able to track

Run: 1

Lead: Luca, Shui


Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer


Grating

Mask

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 star

2.

Run autofocus procedure

3.

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 Acquisition

Task ID:

Depends on:

17

10

Run: 1

Lead: Morrissey


Priority:

Other involved:

Sky conditions:

H

Moderate

Slicer

Filter

Polarizer


Grating

Mask

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 field

2.

Align the science camera for zero order imaging

3.

Remove the N&S mask

4.

Insert the red blocking filter

5.

Remove the grating

6.

Verify the spectrograph is in focus with a flat field calibration arc lamp image

7.

Acquire a star (within 1 hour of zenith) in the guider

8.

Center the star in the guider

9.

Focus the guider

10.

Begin guiding

11.

Download a FPC image, verify properly exposed star image

12.

Capture FPC images at different telescope focus positions

13.

Refocus the guider at the FPC focus position

14.

Verify star image is in a location that will be captured by all 3 slicers

15.

Offset star in guider field if necessary

16.

Insert the large IFU slicer

17.

Download an image, verify properly exposed star image

18.

Focus the telescope of the large slicer

19.

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:

Task ID:

Depends on:

Spectrum Acquisition

18

11, 17

Run: 1

Lead: Morrissey


Priority:

Other involved:

Sky conditions:

H

Thin clouds ok

Slicer

Filter

Polarizer


Grating

Mask

Purpose: The purpose of this task is show that the instrument properly acquires seeinglimited 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 field

2.

Remove the N&S mask

3.


4.

Insert the BH3 grating

5.

Configure for Hbeta observations

6.


7.

Acquire a star (within 1 hour of zenith) in the guider

8.

Center the star in the guider (presuming no offset is required for any slicer)

9.

Focus the guider

10.

Begin guiding

11.


12.

Focus the telescope on the large slicer

13.

Repeat 11-12 for the medium and small slicers.

14.

Reconfigure for BM grating at Hbeta with the large slicer

15.

Acquire a flat field calibration arc lamp image to verify spectrograph focus

16.

Determine best telescope focus for the BM grating

17.

Repeat 14-16 for the medium and small slicers

18.

Reconfigure for BL grating at Hbeta with the large slicer

19.


20.

Determine best telescope focus for the BL grating

21.


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:

Task ID:

Depends on:

Test spectral throughput

19

18

Run:

Lead:

Sky time required:

2

Morrissey

Priority:

Other involved:

Sky conditions:

M

Slicer

Filter

Polarizer


Grating

Mask

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

Observing plan:

1.


2.

Remove the N&S mask

3.


4.


5.

Acquire a standard star (within 1 hour of zenith) in the guider

6.

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 guiding

9.


10.


11.


12.


13.


14.


15.


16.


17.


18.


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: 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:

Task ID:

Depends on:

Test Spectral Throughput of all Slices

20

19

Run: 2

Lead: Morrissey

Sky time required: Twilight

Priority:

Other involved:

Sky conditions:

L

Thin clouds

Slicer

Filter

Grating

Mask

Polarizer


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.


2.

Remove the N&S mask

3.


4.


5.

Point telescope to the zenith during twilight

6.


7.


8.


9.

Record enough images to create a high S/N flat (~1%)

10.


11.


12.


13.


14.


15.


16.


17.


18.


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:

Task ID:

Depends on:

Measure the effect of scattered light

25

Run: Eng

Lead: Luca, Shui


Priority:

Other involved:

Sky conditions:

M

Clear

Slicer

Filter

Polarizer


Grating

Mask

Purpose: Measure the effect of moon light contamination

Observing plan:

1.

Slew to selected position near the moon

2.

Acquire spectrum

3.

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&S

Task ID:

Depends on:

26 Priority: H

1-7, 21, N&S planning test or hand-made script

Run: 1

Lead: Don


Other involved:

Sky conditions:

Matt, Shui, Luca

Moderate

Slicer Large

Filter

Polarizer

BLUE

Out

Other requirements Save Guider Imgs

Grating

Mask

BH2

In

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 field

4.

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&S

Task ID:

Depends on:

27

26

Run: 1

Lead: Don


Priority:

Other involved:

Sky conditions:

H

Matt, Shui, Luca

Moderate

Slicer Large

Filter

Polarizer

BLUE

Out

Other requirements N&S config

Grating

Mask

BH2

In

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:

Task ID:

Depends on:

Guider differential flexure

28

Guider astrometry

Run: Eng

Lead: Luca, Shui


Priority:

Other involved:

Sky conditions:

L

Moderate

Slicer

Filter

Polarizer


Grating

Mask

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

Observing plan:

Reduction plan:


Title: Verify and Characterize DAR Compensation

Task ID:

Depends on:

31 Priority:


7 (Guider plate scale and astrometry)

1 Run:

Lead: Matt, Don


Other involved:

Sky conditions:

H

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

Filter

Large

Blue

Grating

Mask

BL

Out

Polarizer Out

Shui, Luca

Moderate

Observing plan:

Sequence 1:

1.

Telescope in PA mode

2.

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 slice

4.

Offset star to the center of slice 10, configure the DAR tool/software to compensate and track at 380 nm

5.

Take science exposures of a few seconds to and adjust exposure time t to get good

SNR

6.

Take a cadence of exposures as the object rises (sets?) for 40 minutes

7.

Record MAGIQ guider generated offsets and guider images during this time

May 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


Verification that the DAR compensation is valid

Title: Verify Polarizer Capability

Task ID:

Depends on:

32 Priority:


12 (FPC Limiting magnitude)

19 (Test spectral throughput -- optional)

M

Run:

Lead:

2

Matt Other involved: WMKO

Sky 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

Filter

FPC

FPC-ND?

Grating

Mask

BL

No

Polarizer 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 guiding

5.

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:

BL

No

Slicer

Filter

FPC

FPC-ND?

Grating

Mask

Polarizer 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

Filter

Large

Red-Blocking

Grating

Mask

BL

No

Polarizer Yes (0°, 120°, 240°)

Other requirements Guiding

9.

Offset object to center on slice 11

10.

Rotate polarizer to P=0°, 120°, 240° and acquire science image with good SNR at each setting

11.

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:

Depends on:

33 Priority:

27 (Test execution of Nod-and-Shuffle)

32 (Verify Polarizer Capability)

2 Run:

Lead: Matuszewski


Other involved:

Sky conditions:

M

Morrissey, Martin?

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

Filter

Large

Blue

Grating

Mask

TBD

IN

Polarizer


In

Observing plan:

1.

Prepare a nod-and-shuffle observation for the selected extended object

2.

Telescope in PA mode, PA angle set to selected target

3.

Instrument in N+S mode, large slicer, filter, grating TBD

4.

Slew to known polarized extended/diffuse nebula (TBD)

5.

Align on target and rehearse N+S script

6.

Insert polarizer and rotate to P=0° a.

Take a 10+10 minute N+S

7.

Rotate polarizer to P=120° a.


8.

Rotate polarizer to P=240° a.


9.

Retract polarizer a.


10.

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 mode

Task ID:

Depends on:

34 Priority:


M

Run:

Lead:

2

Matt


Other involved:

Sky conditions:

Grating

Mask

WMKO

Moderate

Purpose: Verify direct imaging data acquisition and image reconstruction

Slicer All

Filter

Polarizer


Blue

Out

Out

Out

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 guiding

4.

Focal plane camera in a.

take short exposure of field with focal plane camera

5.

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 in a.



7.

Small slicer in a.



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.

Observing plan

KCWI on-sky commissioning plan

1 Background and Overview

2 Tasks

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Observing plan

KCWI on-sky commissioning plan

1 Background and Overview

2 Tasks

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