IRAF Output File

Specifications of Hydra .iraf Output File

Here are the specs for the iraf file generation capabilities of the Hydra-CTIO software. The hydra cli command listdump writes out an Aperture Identification File, readable by the IRAF multi-fiber packages. The filename of this file will be the Hydra filename with .irafN appended where N is a correlative number. In that way the software never destroy another APF file and the most recent one always has the biggest number. At the end of a field configuration this file is automatically written. The file consists of 3 columns:

1st col Slit number in ascending order.

2nd col "Beam number". To get beam number, look at the title. If it contains the letters "sky" "Sky" or "SKY", write 0. If no object assigned, write -1. Otherwise write 1.

3rd col If the fiber is broken this field will be set to "Broken Fiber". If the fiber is ok and it's on its target position then the field is set to the object title followed by the user number in parentheses. If the fiber is ok and in a place different from the target and park positions then the field is set to "Random position". If the fiber is ok but parked then the field will be set to "not assigned". If there's no fiber attached to this slit position then the field is set to "Gap".

Here is a sample file: