MMIRS Observing Notes

These notes should be used in addition to the MMIRS observing manual:

http://www.cfa.harvard.edu/wiki/mmti/MMTI/MMIRS/ObsManual

and this page:

http://www.cfa.harvard.edu/mmti/mmirs/instrstats.html

that describes the grisms and filters. A paper on MMIRS can be found

here:

http://adsabs.harvard.edu/abs/2004SPIE.5492.1306M

Starting up

The observer sits in front of the Mac guanaco and logs into the MMIRS computer wild from there. Data reduction can be carried out from the Mac zorro by logging into shack. To log into shack or wild, type 'mmirssh' or 'mmirsw' in a terminal.

The startup procedure is normally performed by the observatory staff during instrument checkout. If this is not the case see Section 3.3 in the manual or Section 3.4, if the procedure in Section 3.3 fails. If

the procedure in Section 3.4 fails too see Section 3.5 on problem solving.

Various windows are opened during startup:

mmicemmirs - the main window that an observer works with. In this window you can configure things like the exposure duration, the filter, the grism etc.

toppermmirs - displays graphically the status of the instrument mechanisms such as the dekker, the filter wheel etc.

alignboxmmirs - used for aligning the masks

commentmmirs - allows the observer to add comments to the exposure log and to view it

paddlemmirs - allows the observer to offset the telescope. This window is used for the intial telescope pointing and to align the telluric standards with the mask slits

Exposure Status - displays the status of the observation such as exposure time left, the status of guiding etc.

ds9mmirs - shows the most recently acquired image and the difference between the last and the second last image

All boxes on the 'Startup' tab in the 'mmicemmirs' window should be green. If not go to the 'Start/Stop' tab, check the 'Restart' radio button and restart the appropriate server. You can also restart any of

the GUIs here. Restarting GUI's generally does no harm with a single exception: if 'mmice' is restarted during an exposure, the exposure will be lost.

Taking data

Data taking is done through the 'Config' and 'ObserveOps' tabs in 'mmicemmirs'. The 'Config' tab is used to set up the instrument as needed. The 'ObserveOps' tab allows for traditional observing (one

image at a time) or for performing sequences of exposures (that dither the telescope or cycle through filters, for example) allowing for efficient observing. The sequences are defined by an ascii catalog

file which can be generated with a text editor or by using the 'DitherTool' tab of 'mmicemmirs'. See the instructions on setting up dither files in Appendix D of the manual.

The steps for setting up the telescope and instrument are as follows.

1. Check that all the subsystems are happy, i.e. green, by looking at the 'Startup' tab in 'mmicemmirs'.

2. Go to the 'Config' tab in 'mmicemmirs'

   * Set TELNAME=clay_f5_ir, INSTRNAME=mmirs and DETNAME=mmirs

   * Type your name(s) into the OBSVRS box.

   * Select the correct P.I., which will also set the PROPID. If you switch programs during the night, don't forget to update the P.I.

Once startup has been completed and the 'Config' tab filled in the observer will almost exclusively use the 'ObserveOps' tab in 'mmicemmirs'.

After an exposure is finished, the postproc server will receive the incoming image and display it in 'ds9mmirs' Frame1 on the console. It will also display the difference of the current image and the previous one in Frame2. The usual IRAF programs such as imexamine will still work. In fact you can have imexamine running continuously as new images come in and they will be properly accessed.

The 'ds9mmirs' window is intended to be dedicated to near-realtime display. To look at previous images, it is highly recommend to work on 'wild' and starting a local ds9 using the 'dods9' command. Then use the IRAF/cl in the provided green xgterm windows (Analysis). This did not work and I couldn't start IRAF on 'wild'. You can also access the data directly from 'zorro' with IRAF or IDL, but I didn't try this.

Data can be found on 'wild' in /data/archive/MMIRS/YYYY.MMDD

The 'Clear' button is used to clear the camera in the event of an error. If the 'Go' button remains red because of an error during observing the user must press 'Clear' to reset the system.

3. Take a test exposure to verify that the instrument is working properly.

   * Go to the 'ObserveOps' tab

   * Check the 'MANUAL' radio button

   * ObsType: dark

   * ExpTime: can be anything, I used 1s

   * Filter: dark

   * Click on 'ReadTab' and then click on 'Cancel'. This will clear the readout type and give you a basic double correlated sampled image.

   * Slit/Mask, Grism, Azoff, Eloff and GuideMode are unimportant

   * Enter 1 for first and 2 for last

   * Click 'Go'

   * In the Analysis IRAF window

       cd /data/crunch/MMIRS/YYYY.MMDD

       imarith dark.MMMM.fits - dark.NNNN.fits diff.MMMM.fits

       imstat diff.MMMM.fits

     The mean should be near zero. The stddev should be near XX (this what the manual says).

4. Calibrate the telescope pointing

   * Ask the telescope operator to point to a 13th mag star.

   * Check the 'MANUAL' radio button

   * ObsType: setup

   * ExpTime: 1s

   * Slit/Mask: open

   * Filter: K

   * Grism: open

   * ReadTab: fowler_exp.tab

   * Azoff: 0 and Eloff: 0

   * GuideMode: none

   * first: 1 and last: 1

   * Click 'Go'

   * Click 'Draw Regions' in 'paddlemmirs'

   * Move the green 'star' region in 'ds9mmirs' to the image of the star near the center of the frame. Zoom in and use the arrow keys on the keyboard to finely adjust the placement. If you are unclear about which star is which, select in 'ds9mmirs' Analysis->Catalogs->Infrared->2MASS.

   * Click 'Fix Pointing'.

   * Then click 'Go' in 'mmicemmirs' again. If the star is centered on the yellow rot region, ask the telescope operator to do a 'cset'. Otherwise do another iteration of centering the 'star' region and 'Fix Pointing'.

   * Ask the telescope operator to slew to your first target and run Shack-Hartmann (wavefront sensing).

Observations

Before/After Science Exposures

Each observation should be proceeded by a flat, comp and telluric standard and followed with a comp, flat and Telluric standard. I have heard from one of the Magellan Fellows that Brian McLeod has said that it is only necessary to one comp and one flat and that they can be done in the afternoon before observing. This is partly to prevent persistence of the birght arcs on the CCD.

-Comp and flat

   * Ask the Telescope Operator to pause the guiding

   * Load the dither file 'compflat1.cat'. Select 'CATALOG' -> Click and hold 'Menu' and locate it in the 'Standard' directory. I modified this to take a 3s exposure for the comp because the bright lines were saturated when using the    standard 5s exposure. Loading this file sets ObsType, ExpTime, ReadTab, first and last automatically for you.

   * Make sure the CATALOG button is selected

   * Slit/Mask, Filter and Grism should be what they are during the observation

   * Azoff: 0 and Eloff: 0

   * GuideMode: none

   * Click 'Go'

   * After the exposures are taken, you will be prompted but don't forget to remove the lamp pickoff by selecting 'LampControl' in 'mmicemmirs' and selecting the 'Out' radio button under 'Pickoff'.

- Telluric Standards. Because the atmosphere has many strong absorption bands in the near IR it is necessary to observe standard stars at an airmass close to the airmass of your observations (I have

read values ranging from identical to within 0.1). If your telluric star is close to your field, then you could start by observing the telluric. Then observe your object till it transits, and go back to

the telluric, and then resume your observations. Telluric standards with K=7 are appropriately bright. There are telluric standards included in the automatically generated catalog that is made for mask

observations (ask the TO to see the list, I can't find it on any of the astronomer controlled computers). Not sure if it is necessary to bracket long observations with a pair of telluric standard observations.

The afternoon mask measurement process will generate a dither catalog that will offset the telescope to put the telluric standard on each slit of a mask. The alignment procedure for the telluric is as

follows:

   * Tell the TO to point at the telluric standard star with guiding on

   * Check the 'MANUAL' radio button

   * ObsType: setup

   * ExpTime: I used 10s for a K=8.6 standard, 5s for a K=7.0, but adjust for stars of different magnitudes 

   * Slit/Mask: open

   * Filter: K

   * Grism: open

   * ReadTab: fowler_exp.tab

   * Azoff: 0 and Eloff: 0

   * GuideMode: none

   * first: 1 and last: 1

   * Before you click 'Go', ask the TO to turn off guiding

   * Click 'Go'

   * Click 'Draw Regions' in 'paddlemmirs'

   * Move the 'star' region in 'ds9mmirs' to the telluric standard. Zoom in and use the arrow keys on the keyboard to finely adjust the placement.

   * Click 'Fix Pointing' in 'paddlemmirs'

   * Click 'Go' one more time to check alignment. The star should be centred on the yellow 'rot' region. This can be hard to see, so feel free to invert the colors on ds9mmirs by going to 'color' menu at top, and then select invert colormap.

   * In 'mmicemmirs', press CATALOG -> MENU ->Mask->maskname to load the dither catalog appropriate for you mask. You need to hold down the mouse button to see the submenus when clicking 'Menu'. Make sure to check 'CATALOG' instead of 'MANUAL'

   * ObsType: object

   * ExpTime: I used 30s

   * Slit/Mask: Choose the one that corresponds to the dither catalog

   * Filter: H (choose whatever filter you want to observe with)

   * Grism: H (again, choose whatever you want observe with)

   * ReadTab: ramp_5sec

   * Azoff and Eloff are set by the dither file

   * GuideMode: none

   * first: 1 and last: 5 The manual says that the dither catalog will put the star down each slit of the mask but it seems (from previous experience) that only the first 5 are necessary (this is the reason for last being set to 5). These are the center, top-, bottom-, left- and right-most slits on the mask. The feeling is at LCO that with more experience it may turn out that the telluric standard only needs to go down on slit.

   * Click 'Go'

#############################ONLY IF NEEDED##############################

The dither catalog mentioned above is generated from the mask design files by an LCO staff member on the day of a mask change. It can be found on 'shack' in /data/archive/MMIRS/Masks-YYYY.MMDD.cat. It can also be found on guanaco in /Volumes/ARCHIVE_MMIRS, so that the telescope operator can copy it. However if this was not done, you can do it yourself (but this didn't work for us). The steps are:

   * Configure the observation in 'mmicemmirs'

      * Filter: K

      * Grism: open

      * Slit/Mask: choose the desired mask

   * Go to the 'Mask Alignment' tab in 'alignboxmmirs' and click 'Start' to retrieve the config params

   * Click 'Measure Mask', which will take an image and will update the mask file and mask image fields.

   * Do this for all your installed masks.

########################################################################

Science Observations

- Observing your targets

   * Ask the TO to slew to your target

   * First the mask needs to be aligned. In 'mmicemmirs':

      * Check the 'MANUAL' radio button

      * ObsType: setup

      * ExpTime: leave not important

      * Slit/Mask: choose the mask you want to observe with

      * Filter: H (choose whatever filter you want to observe with)

      * Grism: open

      * ReadTab: fowler_exp.tab (possibly not important)

      * Azoff and Eloff are set by loading the dither catalog

      * GuideMode: none

      * first: 1 and last: 1

    * In the 'Mask Alignment' tab in 'alignboxmmirs':

      * Click 'Start' to retrieve the config params

      * Ask TO to run Shack-Hartmann (wavefront sensing) but no rotator guiding.

      * Click 'Apply Nominal Offset'

      * Set 'exptime' to 10s and check the 'open' radio button.

      * Click 'Take Alignment Image'

      * The image will be displayed and you can examine each alignment star in turn by clicking on the 'Next Box' button.

         * If the alignment stars are not in the red regions, move the 'star' region onto the corresponding star (you only need to do this for one star), verify that 'Fix To Nearest' is selected and click 'Fix Pointing'. Click 'Take Alignment Image' again. Repeat until the stars are in the red circles.

         * If the stars are in the red circles but not near the boxes, click 'Apply Offset' and then 'Take Alignment Image'. When the stars are either in or very close to the boxes check the 'mask' radio button, click 'Apply Offsets' and then 'Take Alignment Image'. This can be repeated until the stars are centred in the boxes. and dx < 0.5, dy < 0.1, and dr < 100.

   * Ask the TO to run a "turbo" to initiate rotator guiding.

   * If this is your first exposure of the night, take another alignment image with the rotator guiding on to make sure everything is running smoothly.

   * In 'mmicemmirs':

      * Load a dither file by clicking 'CATALOG' -> 'MENU' and selecting the appropriate file in the 'Standard' directory. I used 'mos_10arcsec_12.cat'.

      * ObsType: object

      * ExpTime: I used 300s (12x300s=1hr in total)

      * Slit/Mask: Leave it as the mask you want to observe with

      * Filter: H (choose whatever filter you want to observe with)

      * Grism: H (again, choose whatever you want to observe with)

      * ReadTab: ramp_5sec

      * Azoff and Eloff will be set automatically by the dither file

      * GuideMode: autoguide

      * first and last will be set automatically by the dither file. These correspond to the lines in the dither file and can be changed if you don't want to used all dither positions.

   * Verify in 'Exposure Status' that the guiding status is 'YES'

   * Verify that a wavefront sensing star has been selected. It is OK to start the exposure before the wavefront correction is perfect.

   * Click 'Go' to start observations

End of the Night

- Dark frames. At the end of the night you should take dark frames for every exposure duration that was used during the night. Fortunately you don't have to do this manually. In a shell window (does it matter which machine you are logged into, i.e. 'shack' or 'wild'), type:

            cd /data/ccd/MMIRS/YYYY.MMDD

            darkscript 5

Then in 'mmicemmirs' load the correct file from the Menu->Darks directory, this should also check the 'DITHER' radio button. The 'darkscript' instructs you to change the TELNAME=test in the 'Config' tab in 'mmicemmirs'. Ignore the subsequent warning about this.

Observing log

An observing log is keep automatically, although comments have to be entered manually - highlight the observation in the list on the left and then type your comment into the 'Comments' box on the right. The log can be viewed by clicking 'View Log' in 'commmentmmirs'. A postscript copy of the log file can be found in the directory containing the data from that day. You can upload this log with comments at the end of the night into a Google Docs Spreadsheet by looking for commlog.tab in /data/ccd/MMIRS/YYYY.MMDD/   If you copy this file into /data/crunch/MMIRS/YYYY.MMDD/ you can use Google Docs upload file by looking in DEVICES -> guanaco -> minidisk -> Users -> magf5 -> CRUNCH_MMIRS -> YYYY.MMDD -> commlog.tab

Getting your data

The best way to take your data away from the telescope is to use a portable harddrive. The data directories are cross-mounted onto Zorro for easy access. Your portable harddrive can be plugged into zorro's monitor. The data can be copied directly using the Finder or from a unix shell. After you are done, eject your disk using the Finder, and unplug it. From zorro the archive data can be found in /Volumes/ARCHIVE_MMIRS and the crunch data (where you may have some processed files) can be found in /Volumes/CRUNCH_MMIRS. Alternatively, you can use rsync or scp to copy over the data, e.g.:

rsync -av -e ssh obs2@guanaco.lco.cl:/Volumes/ARCHIVE_MMIRS/2010.1023 .

Problems & troubleshooting

- At one point I would set GuideMode to 'none' but then clicking 'Go' would turn it back to 'autoguide'. Clicking 'ConfigObs' in the 'ObserveOps' tab in 'mmicemmirs' after setting it to 'none' fixed the problem.

- Loading a dither file can adjust the Azoff, Eloff, first and last values. If you load a file and then change your mind you should make sure to reset these values.

- The mask alignment images actually have the name of the telluric standard (in my case) as part of their filename. I don't know how to change this.

- At one point we had a lot of trouble aligning the stars. The stars were not moving consistently relative to the red circles after clicking 'Fix Pointing'. It may have been something I clicked (by accident) or it may have been because we were doing this while very close to the zenith. We tried re-acquiring the field but that didn't work, we then restarted 'alignbox' and 'ds9' (on the 'Start/Stop' tab in 'mmicemmirs') and re-acquired the field and that fixed the problem.

- The 'dods9' command did not work.

- Couldn't start IRAF after using the command 'mmirsw' to ssh into 'wild'

- On the first night our dither catalogs (that are produced from the mask images) were incorrect. There should be one dither position for every slit in the mask. Masks that had 9-16 slits weer found to have 0-5 dither positions. We attempted to use procedure outlines above to generate new dither catalogs but we couldn't get it to work.