Science Operations

LBC Quick Review

Night Prep

Open an x2go session on robs (robs.mountain.lbto.org), using your partner account (INAF,LBTB,OSURC,AZ or LBTO) and using the MATE desktop. Session preferences for an LBTO login are shown here.

Insure that the scripts are accessible from robs.

  • On robs, cd /lbt/data/old_homes/ to access /home/ on the mountain workstations, obs[2,3,4].
  • Calibrations scripts are available on robs at /home/lbto/Calib_OBs (a symlink to the /home/lbto/Calib_OBs/ directory on obs[2,3,4])

Beginning of the night

On robs, all of the windows and sessions that are needed to observe with the LBCs can be launched with a click of a button. From the Applications menu at the top left, select Graphics and then LBC, as illustrated here. This will launch the windows/sessions listed below. In parenthesis is the way to launch this window/session from a terminal window. Note that, lbc_idl is needed; simple idl will not load the paths needed for LBC related IDL procedures.

  • a chromium browser open to the LBC User Interface URL (lbc_cmu)
  • an IRAF session (lbc_iraf)
  • an IDL session (lbc_idl)

Open a terminal window and type RB_Science in it to launch an RB_Science session. This version of RB_Science has been thoroughly reworked and is more robust than the older version. This new version has various command line options (type RB_Science –help/howto on the command line for brief or extensive documentation), but the LBC icon launches only the standard, default version. Examples of some of the more useful options are being compiled here.

The windows may need to be resized. The downward pointing caret (“v”) will iconify the window, while the upward pointing caret (“^”) will toggle back and forth between full screen.

Turn on the LBCs & establish the TCS connection

The LBC User Interface has 5 panels: House Keeping, Power Control, OB Execution, Log Analyzer and Information. By default, it comes up with the House Keeping screen displayed.

Go to the Power Control page

  • The House Keeping should be on (“ready”). If not, turn it on.
  • The “Other Systems” (Cameras, Trackers, Filters and Rotator) should be off, but “enabled” (meaning ready to be turned on). Click the button to turn these on.

Note: If the ambient temperature is less than 0 C, then click the “Warm Up” button first and wait ~10-min for each degree below 0. Then click the “Turn on” button.

Once the operator says that the LBCs are authorized, click the “Connect LBC” button at the top (both sides for binocular, left or right to use LBCB or LBCR only).

RB_Science

Clicking on the LBC application will launch RB_Science. You should see a ds9 window with the title “LBCView” and the LBCB and LBCR images will be displayed to two frames as they appear in the archive.

RB_Science can be launched from the command window, and this manner of starting it provides more flexibility in its use.

IDL

The LBC application will also have launched an IDL session. If you need to launch IDL from a terminal window, then use the command lbc_idl (not just idl).

IRAF

The LBC application will have launched an xgterm window and started an IRAF session in it.

  • In IRAF, epar LBTtools and set the 
  • camera to LBC
  • archive to /lbt/data/new/   (/lbt/data/new on robs = /newdata on obs[2,3,4])
  • utdate to the UT date for the night in the format, YYYYMMDD
  • :wq to save parameters and exit
  • type LBTtools to load the LBTtools package
  • type Observe to load the Observe package, which contains lbcrangebal
  • type LBC to load the LBC package, which contains allseeing
  • create a working directory. robs does not have a /scratch disk, so on robs, you’ll have to work under your partner account. The upgraded obs[2,3,4] will hopefully have /scratch disks with plenty of space available.
  • In IRAF, cd /home/<partner>/your_dir. Do any IRAF work in this directory, since it is local and you have write permission to it.
  • type prepdir to create the subdirectories under /home/<partner>/your_dir that are needed by LBTtools tasks.

Take test images

  • On the OB Execution Page, upload and play the script /home/LBTO/Calib_OBs/BIASDARK/2Bias_Bino_Checkout.ob. 

Open ancillary tools

LBTplot: In a terminal window, type LBTplot to launch this tool.

Observe!

Step 1: Collimation & Co-Pointing

    • Upload the script to take the pair of co-pointing images for the first field. 
    • Play this script, count to 3 and stop it in order to slew to the field but not take any images there.
    • In the IDL session, type dohybrid, if the first collimation of the night or the first collimation after active optics has been cleared, or dofpia if not. Wait until it has finished.
    • Once again, upload the co-pointing script.

      • This time, play it to the end.
    • epar lbcrangebal to enter the timestamps (hhmmss) of the resulting blue and red images and :go to execute the task.

        • When prompted, position the cursor over the co-pointing star indicated on the finding chart and click the spacebar. The task will direct you to do this first on the blue image, then on the red image.
        • Enter “Y” to send the corrections if they are reasonable (few mm, 10’s of arcsecs)

Step 2: Science Observation

    • Upload and play the science script which corresponds to the co-pointing script just executed.

Repeat steps 1 and 2 for each target.

Calibrations

  • Twilight flats are necessary (dome flats are not possible).

    • Recent flats can be found at this table
    • Use mkskyflat to create OBs to check counts (SkyFlatTest_*.ob) and obtain a series of 5 dithered flats (SkyFlat_*.ob). On the User Interface, you can pause and change the scaling factor for the exposure time.

End of Night

  • Disconnect LBC
  • Turn off “Other Systems”