MULTISPEC is a code for the automatic extraction of multiple spectra from slitless exposures of dispersing elements such as objective prisms, grisms, or gratings. The code has been optimized for crowded fields composed of point sources such as resolved stellar clusters. MULTISPEC obtains the spectra by multiple profile fitting and is a spectral analog of a profile-fitting photometry package such as DAOphot or HSTphot. The first versions of MULTISPEC (1.0.x, 1.1.x) could only be used with HST/STIS NUV-MAMA objective-prism data. Version 1.2 added support for HST/STIS FUV-MAMA G140L data. For version 2.0 the full code was rewritten in order to generalize it to arbitrary slitless data. The current version includes the calibration files for the modes cited above plus a generic uncalibrated mode. Future versions will add calibration files for more modes.
To install MULTISPEC, start by creating a directory where the program will be located. We will call the path to that directory MULTISPEC_DIR and it should be included in your IDL_PATH system variable before you invoke IDL (if you need help on setting up IDL_PATH, see this web page). Now, download this file into that directory. At the unix shell prompt in MULTISPEC_DIR type:
unix shell > gunzip multispec.tar.gz unix shell > tar xfv multispec.tar ... lots of files ... unix shell > ln -s multispec_6.3.sav multispec.sav
And with that you are (almost) ready to start using MULTISPEC! But before we do that, here is some additional information: