MOOG

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MOOG is a code that performs a variety of LTE line analysis and spectrum synthesis tasks. The typical use of MOOG is to assist in the determination of the chemical composition of a star. The basic equations of LTE stellar line analysis are followed, in particular using the formulation of F. N. Edmonds, Jr. (1969, JQSRT, 9, 1427). Much of the MOOG code follows in a general way the WIDTH and SYNTHE codes of R. L. Kurucz (see his web site: http://kurucz.harvard.edu/). Below are instructions on downloading MOOG. If you have trouble grabbing or decoding the code please email me at chris@verdi.as.utexas.edu.

The coding is in various subroutines that are called from a few driver routines; these routines are written in standard FORTRAN77, except for one "c" routine that is non-essential. The standard MOOG version has been developed on unix and linux computers, but should work also on Macs.

One of the chief assets of MOOG is its ability to do on-line graphics. This means that the plotting commands are given within the FORTRAN code. MOOG uses the graphics package SM, chosen for its ease of implementation in FORTRAN codes. Plotting calls are concentrated in just a few routines, and it should be possible for users of other graphics packages to substitute other appropriate FORTRAN commands.

The current MOOG release (April, 2002) is the only code that is actively supported. A soon-to-be released version can be used, but almost surely has remaining bugs to be caught and eliminated. See below for downloading instructions of these codes.

Finally, financial support from the US National Science Foundation and NASA for many years in development of this code is gratefully acknowledged.

abfind in MOOG

A standard MOOG running option called abfind force-fits abundances of species to yield computed equivalent widths that agree with observed ones previously measured with other software packages. Here is a sample graphical output from this mode.

Example of abundance output from equivalent width matching: these are Fe I abundances from individual lines plotted as functions of excitation potential (top panel), reduced equivalent width (middle panel), and wavelength (bottom panel). The dashed yellow lines represent the mean Fe I abundance, and the dashed blue lines represent (linear) trends of abundance with the three variables. The middle plot also contains information about the stellar model atmosphere used in this computation, and the bottom plot has information on the stellar equivalent widths. The vertical axis abundance units are logarithmic number densities on a standard scale in which log ε(H) = 12. The user can alter some of the computations (such as assumed microturbulent velocity) while the code is running. Click on picture to see larger image

synth in MOOG

The other standard MOOG running option called synth computes a set of trial synthetic spectra and (if the user so desires) matches these to an observed spectrum. Abundances can be deduced either bu visual inspection of the plot or by mathematical minimization of the observed-computed spectrum difference.

Example of synthetic spectrum computations and their comparison to an observed spectrum: This spectrum contains a complex blend of weak CN molecular lines and significant features of rare earth species La II, Ce II, Nd II, Sm II, Tb II, and Tm II. Some abundances have been altered from their input values, as listed in the figure legend, and the abundances of Tb and Tm have been varied for each synthesis. the colored lines represent the 4 synthetic spectrum computations, and the white dots represent the observed spectrum. The bottom panel shows the spectra plotted together, and the top panel shows the "o-c" comparisons of synthetic and observed spectra. The abundance units are logarithmic number densities on a standard scale in which log ε(H) = 12. Click on picture to see larger image

How to acquire MOOG

You may obtain a copy of MOOG via ftp.

The current version of the code was released in April 2002. To obtain it, click: MOOG2002. The downloaded file will be called MOOG2002.tar.gz. This code can be used only with SM. graphics package

To obtain the experimental (2007) version of the code, click: MOOG2007. The downloaded file will be called MOOG2007.tar.gz. The user is warned that this version almost certainly contains errors, and should be used only for testing, NOT research purposes.

Not sure whether or not you would like MOOG? You are welcome to download a postscript file describing the current program. It is called WRITEMOOG.ps.

Note: If do not have the plotting package SM on your system, it is available at a modest cost. Send messages of inquiry to Patricia Monger (monger@mcmaster.ca), or go to the SM web site.

How to install MOOG

Once you have obtained MOOG via ftp, on a UNIX machine execute the following commands:

gunzip MOOG2002.tar.gz             (or: gunzip MOOG2007.tar.gz)

(this uncompresses the file)

tar -xvf MOOG2002.tar              (or: tar -xvf MOOG2007.tar)

(this separates the individual files; you should end up with many *.f files, one *.c file, several *.com files, a Makefile, and a program description called WRITEMOOG.ps. The WRITEMOOG.ps file can be sent directly to your laser writer)

make -f Makefile.redhat            (or: make -f Makefile.solaris)

(this compiles MOOG and links to the appropriate libraries in "redhat" linux (or "solaris" unix); note that the appropriate paths to libraries on your machine will need to be set in Makefile.redhat (or Makefile.solaris)

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