SQIID Target of Opportunity Observations (ToO)

The typical Target of Opportunity (ToO) observation for SQIID entails deep observations of a transient target, such as a Gamma Ray Burst. A special script is available that moves the telescope a pseudo-random distance between exposures. Hopefully the tcl code has been copied to the wfire subdirectory (located within /data2/2meter/wfire at the 2.1-meter and within /data1/4meter/wfire at the 4-meter) for easy access. Since these scripts are not part of the static WILDFIRE dictionary, they must be sourced from within the Instrument Control window by sourcing a file called setup_grb:

source /data2/2meter/wfire/setup_grb.tcl

This file executes the following commands:

     source /data2/2meter/wfire/randith2d.tcl
     source /data2/2meter/wfire/jrand.tcl
     source /data2/2meter/wfire/getdelay.tcl
     source /data2/2meter/wfire/randseed.tcl
     set iseed 17427
     setIntegration 15.0 0.11 10           (15*10+40 = 190 seconds)
     pics 1
     tcp_on

Command useage is:

randith2 N_pictures min_offset_x min_offset_y max_offset_x max_offset_y

A typical choice would be:

randith2 15 4 4 10 10

which would take generate 15 images and take about 2250 seconds total integration time and probably burn about 50 minutes of wall clock.

If the special scripts noted above are unavailable, one should do the following:

Use set-time to set JHK integration time to 15 sec and coadds to 10.
Run one of pattern scripts such as:

do_9spiral with a separation of 8 to 10 arcsec. Run this twice
do_standard_on with a separation of 8 to 10 arcsec. Run this thrice.
do_field_on with a separation of 8 to 10 arcsec and a 4 by 4 grid.

The integration time of 15 sec is conservative, intended to keep things on scale. If your own observations suggest that a longer time, such as 20 to 25 seconds keeps counts below 8-10000 adu in H and K, then by all means use what's been working. Adjust the coadds to get a frame-time near 150 sec and the total number of frames to get a total integration time of 2200 to 2400 seconds. Under normal circumstances these data can be used to generate a sky and a flat so that only a set of darks with the same integration time as the data need to be taken. If other flatfield data are available, it should also provided to the ToO team as backup.

merrill@noao.edu
2007 March 14