Science Operations

LBC Quick Review

Night Prep

Open an x2go session onto obs1 or obs2 (mountain.lbto.org), using your partner account (inaf, lbtb, osurc, az or lbto; note that these must be lower case) and using the MATE desktop.

Insure that your scripts have been uploaded. Note that the home directories of obs1 ,obs2 and robs are not cross-mounted. We are still working on some configuration issues with the new machines. For now:

  • The home directories on the old computers (obs4, now called obs-32bit) are available on obs1, obs2 under /lbt/data/old_homes/.
  • Scripts to take biases are available at /lbt/lbto/lbc/Calib_OBs/BIASDARK/

Beginning of the night

On obs1 and obs2, 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)
  • an FPIA monitor session (lbc_fpia_monitor)

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 (or –howto) on the command line for brief (or extensive documentation). Examples of some of the more useful options are being compiled on the LBC Software page.

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

Type RB_Science to launch the program which will open a ds9 window and display the LBCB images in one frame and LBCR images in another as they are taken and saved to disk. If you need to restart RB_Science, use the command, RB_Science --starttime -1, to display the last pair of Blue/Red images and wait for subsequent ones.

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. If you need to restart it, you may do so from any terminal window by typing the command lbc_iraf.

  • In IRAF, epar LBTtools and set the 
  • camera to LBC
  • archive to /lbt/data/new/   (/lbt/data/new)
  • 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. obs1 and obs2 do not have a /scratch disks, so you’ll have to work under your partner account (suggest working under ~/Scratch/<utdate>).
  • In IRAF, cd /home/<partner>/Scratch/<utdate>. 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>/Scratch/<utdate> that are needed by LBTtools tasks.

Take test images

  • On the OB Execution Page, upload and play the script /lbt/lbto/lbc/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”