This is a summary of normal IGRINS use for observers at DCT

Before You Begin:

Check IGRINS is healthy, verify with your TO

Observing timelines: 

First half of the night:

• 1 hour before sunset: take calibrations
•  20 minutes past sunset, your TO will open, do wavefront tests, and perform a nightly pointing check. This should take 20-30 minutes
•  40 minutes after sunset, your IGRINS on-sky time begins 

Second half of the night:

• begin with observing
•  20 minutes after sunrise, your TO will close, during which they will move the telescope to zenith. Then, you will take calibrations (about 1 hours)
•  80 minutes after sunrise, your TO can shut down the telescope

Full night:

Follow the first half of the night timeline (calibrations are only needed at the start of the night)

Start of Night:

1. Wake up ICC on the right (a big iMac) and close all windows (HKP, DTP, SCP, QLP, IGRINS Hub) if they happen to be open (HKP and the IGRINS Hub should have been open, make sure to close it)

2. Turn on the IG proxy by clicking the icon on the top right corner of the iMac desktop

3. Turn on the IG software (HKP house keeping package, SCP slitview camera, DTP data taking package) by opening a new terminal and typing

> cd ~/igrins_admin
>sh icsrun_dct.sh
when it launches, the "IGRINS Hub" window will pop up

you should see the "check Mount" and "check Proxy" change from "..." to "Okay" status

Start the HKP (click "run HKP"). In the HKP gui, click the “periodic monitoring”  and, below that, the “Send Alert (T>20)” buttons

 Once you see that the HKP status says "connected" in the Hub, start the SCP (click "run SCP"). You should see the SCP window pop open

 Once you see that the SCP status says "connected" in the Hub, start the DTP (click "run DTP"). You should see the DTP window pop open

4. Check the software

In the SCV, check if you are receiving the TCS information or not (blue values on the upper right, including RA, Dec). 

Note -  TCS will not be running without your TO. Images and cals can still be taken but headers will be incomplete.

In the Status box, the following lines (for the SVC, and then for both H and K in the DTP) should appear:

• •  “[time] NFS connection succeeded”
  •  “[time] Detector Status Check”
  •  “[time] Detector is Ready” 

5. Test Exposures

Take a test image on both SVC and with the HK detectors to test readout

• • Turn off ‘automatically save’ if you prefer
  • Use shortest exposure 1.63s

If you see noise pattern or low-resolution image, repeat the short exposures or contact observing support

Calibrations:

First half of the night - order should be tests, darks, flat offs, flat ons, science

Second half of the night - order should be test, science, flat offs, flats ons (to reduce persistence from the flat lamps on the calibrations)

Note - if TCS is not running (run by TO), the header information will not be complete. There will be error messages about the missing header information if exposures are saved, but that can be ignored.

1. Darks

(May be done without a TO.)

Check all the lights are off around the telescope

Setup:

• • dome is closed
  • instrument cube is closed
  • all lights are off

Note - the telescope has to be at zenith to close the cover

Using the DTP, take darks:

2. Flats

(TO is required)

Ask your TO to:

• • move the telescope to flat position
  • open the telescope and instrument cube
  • put in the IGRINS fold mirror
  • turn on TCS

A. FLAT OFF: Take flat offs before the flat lamps are on (required for pipeline)

Wait for your TO to make sure the telescope is ready

Using the DTP:

B. FLAT ON: Take flats with the flat lamps on (also required for pipeline)

Kindly ask your TO to turn on the IGRINS Flat lamps (150 W bulbs)

Using the DTP:

Taking Data:

Note- remember that if you are on the first half of the night, your TO will first need 20-30 minutes to open, do wavefront tests, and perform a nightly pointing check.

1. Focus

 1. Telescope Pointing Procedure

A. Define your pointing

Preferred - use a target list as described in the Advanced Options section:

Tell your TO that you are using a target list, and they will screen share with the IG computer. Then you will highlight the target entry on your list and click "Send to TCS". Your TO can then move to your target

Alternatively - you may tell your TO the coordinates of your object, and they will point the telescope accordingly

B. Once on target, take a test image with the SVC (see below)

C. Check that you are pointing to the correct field

2. Using the SVC

Taking an SVC image:

standard practice should be to click "compress" (10% the file size)

Dither directions:

A command to go 50 arcseconds north moves the telescope 50 arcseconds north, and your stars move 50 arcseconds south

So, if your target is to the north of the slit, then you need to move north to get it into the slit

Note: Unless absolutely required for your science, please disable the autosave feature on the slit camera viewer. This will save 30GB of space each night. 

3. Using DTP to obtain spectra

Taking H/K spectra:

When the exposures have completed, you will hear the computer voice  "H Finished" then "K Finished"

Note: The RA and DEC boxes in the DTP must be populated in order for the frames to be saved. If they are missing you will waste a full exposure time.

Nodding:

Note: When keeping logs, track the A or B location of your frames. Your data reduction will be better in cases where you manually change the nod location or have bad frames.

Note: The A and B box positions need to be verified each night because the slit moves in its holder up to 5 pixels between observing runs.

Sky spectra:

Note: You need at least one 300s sky frame each night for the PLP to work correctly. If you will not get one of these for your science, then get one to help with reductions.

Additional Options:

1. Looking at your data

ds9:

files will automatically open in ds9 if you click on them in Finder

data is stored in 'obs_data'

this folder is conveniently found in any Finder window on the top left

Quicklook:

 > cd igrins/igrins_admin

  >sh run_qlp.sh

 This will open two different windows (each H and K)

 Checking the "fits" button will enable you to look at a specific image, or alternatively, the "Auto Refresh" button will update with each newly obtained spectra.

2. Using a target list

Loading in your target list:

3. Changing the PA

The default PA is East-West (90 degrees)

4. Guiding

A. No Guiding

For exposures less than 300s, guiding is not necessary at the DCT. 

B. On-Slit Guiding with Target

When your target is bright and relatively unsaturated in the SVC 

1. 1. Choose "Gaussian 2D" or "" as a centroid algorithm. 
   2. Place the target on the reference position by clicking the target, and "Go R" button on the ***
   3. dAX & dAY, dBX & dBY can be redefined for either AB nodding or On-Off nodding 
      1. Click "Select A-B & Guide Position" if these were changed
   4. Click "Set Reference & Ready to Guide"
   5. In the DTP window select "Move A" and then "Start AB Box"
   6. Monitor guiding

C. Off-Slit Guiding with Guide Star

Method 1: Unknown Offset (Target visible but faint) - click and guide.

Off-slit guiding when you see the target and the guide star in a slit camera view but don't know the offsets. 

1. Choose "2D Gaussian Fitting" as a centroid algorithm. 
2. Place the target on the reference position by clicking the target, and "Go R" button.
3. dAX & dAY, dBX & dBY can be redefined for either AB nodding or On-Off nodding 
   1. Click "Select A-B & Guide Postion" is these were changed.
4. Click "Use Guide Position". 
5. Click the guide star and "Sel G". Make sure the pink box moved on to the guide star.
6. Click "Set Reference & Ready to Guide".
7. In the DTP window select "Move A" and "Start Guide Box".  --Watch guiding.

Method 2: Known Offset in Slit_length (dSL) and Slit_width (dSW)

Method 3: Known Offset in RA

Off-slit guiding with known offsets in RA & Dec between a (faint) target and a guide star.

Method 4: Known Offset in Pixels

Off-slit guiding with known offsets in Pixels between a (faint) target and a guide star.

1. Choose "2D Gaussian Fitting" as a centroid algorithm. 
2. Click "Use Guide Position" in DTP. 
3. Enter nod position and guide offsets.
   1. dAX & dAY, dBX & dBY can be redefined for either AB nodding or On-Off nodding.
   2. Type dGX and dGY values in pixels.
4. Click "Select A-B & Guide Postion".
5. Take a single exposure on the Slit Camera View (SCV) package
6. Click the guide star on the Image Window.
7. Click "Go G" button and take a single exposure to see the pink box moved to the guide star.
8. Target is now located back on the reference position ("R").
9. Click "Set R & Ready to Guide".
10. "Move A" and "Start Guide Box".  --Watch guiding.

Note that the annular guiding (DCT Guiding system) is currently not an option with IGRINS due to the focus required for IGRINS.

5. Using the ABBA script

6. Saving your data

We are working on a best method for distributing data to observers.

All IGRINS FITS files are 16.8MB. The average file size of a 1 night run is ~32GB, but this varies depending on your choice to automatically save all the SVC files. The spectroscopic files require ~5GB of disk space each night.

If you are at the DCT for the observing run, then we recommend you save your files on your own storage device. You can easily connect to the ICC and copy your files with a USB connection.

End of Night:

1. On the HKP gui, make sure that the “periodic monitoring” (which will say "pause" if it is already selected) and, below that, the “Send Alert (T>20)” buttons stay in effect and that this package stays open and running

2. Close the SVC and DPT windows. You should see the status change in the IGRINS Hub to "disconnected"

3. Close the IG proxy 

Do not log out of the IG computer, it will go to sleep on its own accord