GEMINI (April2024)  Gemini IRAF package v1.16   GEMINI (April2024)

Release date: April 22, 2024

This document describes the revisions relative to the Gemini IRAF package
v1.15.

Gemini distribute and install the Gemini IRAF package with conda.  Installation
instructions can be found at: 

    https://www.gemini.edu/observing/phase-iii/reducing-data/gemini-iraf-data-reduction-software


A tarball is also available from the Gemini website.  Manual installation
instructions for the Gemini IRAF package are included in the gemini_readme.txt 
file. The tarball, gemini_v116.tar.gz, can be obtained from:

   https://www.gemini.edu/observing/phase-iii/understanding-and-processing-data/data-processing-software/download-latest

The Gemini IRAF package v1.16 has been fully tested and vetted *only* in the 
PyRAF environment.  Most of the package works under IRAF CL, however we have
experienced irregularities here and there.  Therefore, we encourage people to
use PyRAF to avoid problems.

This Gemini IRAF package was tested with the conda package of IRAF v2.16. 
The package does NOT work reliably with version of IRAF v2.16 was once 
distributed by NOAO.  The IRAF conda package is a version modified to fix
bugs and for compatibility with Gemini IRAF.

The Gemini IRAF package cannot be built on Mac OS 10.15 and above because
those platforms are not distributing 32-bit compatibility libraries.
A VM is available.  See instructions here: https://gemini-iraf-vm-tutorial.readthedocs.io/en/stable/

PRIMARY REVISIONS
=================
1) GMOS package:
            a) Support for the new GMOS-S CCDs installed late 2023.

2) GNIRS package:
            a) Support for the new GNIRS low- and high-resolution IFUs.
            b) Improved propagation and usage of the data quality (DQ) plane.


DETAILS OF THE REVISIONS
========================

Only the most notable changes or those more likely to be of interest to 
the users are highlighted, minor bug fixes are not.

1) GMOS Package
----------------
Instrument: GMOS

    a) Support for the new GMOS-S CCDs

       New CCDs were put in GMOS-S at the end of 2023.  Following the 
       commissioning and characterization of the CCDs, the GMOS package
       was updated with revised look-up tables for gain, readnoise, etc,
       new quantum efficiency correction, new CCD alignment geometric 
       transformation (gmosaic).  The package remains backward compatible
       with all older CCD configurations.

2) GNIRS Package
----------------
Instrument: GNIRS

    a) Support for new low- and high-resolution IFUs

       Two new IFUs have been installed in GNIRS.  Existing code for the
       defunct old GNIRS IFU was refactored, fixed, adapted,  and improved 
       upon to support the new IFUs.  Reviving the old code was the fastest
       solution as DRAGONS is not yet ready for IFU support.

    b) Better propagation and usage of the DQ plane

       Support for the new IFU required some improvements of the handling
       of the DQ plane.  Users might notice differences in the DQ plane
       of XD data as well.


SUMMARY OF NEW TASKS AND NEW SUPPORT FILES
==========================================

NEW TASKS:

  gnirs.nfapsum:
    Integrate flux spatially oever extensions (IFU slices) to produce a 
    1D spectrum (mostly for standards).

  gnirs.nfnormslices:
    Uses wavelength-rectified data to measure relative slice levels and 
    reincorporate throughput variation between slices into a flat.


NEW SUPPORT FILES:

  gmos/data:
    New MDFs, new BPMSs for new GMOS-S CCDs

  lib/gemini.h:
    New bit definitions for data quality mask.

  gnirs/data:
    New L and M-band sky line lists
    New MDFs for GNIRS IFU low- and high-resolution

  gnirs/doc:
    New example for GNIRS low-res IFU


SUMMARY OF ALL MODIFIED PARAMETERS
==================================
If a task listed below is causing problems, it is very likely that the task is
accessing an old parameter file that does not contain the updated parameters
and/or values.  To resolve the problem, the old parameter files for the 
Gemini IRAF package must be removed from the uparm directory.  To do this, 
initialize the uparm directory by typing "rm uparm/*" in your iraf home 
directory (ie., where you ran mkiraf / where your login.cl file is located).
NOTE: if you wish to make a note of any stored parameters, please do so before
running this command.  If it is not desirable to remove all the old parameter
files for the Gemini IRAF tasks, it is possible to "unlearn" the individual
task.

Please see the appropriate help file for more information about the specific
parameter changes listed below.

    gmos.gfcube
      - New parameters:     dqthresh

    gnirs.nstransform:
      - New parameters:     dqthresh

    gnirs.nsextract:
      - New parameters:     fl_corner