# Artificial galaxy simulation format

This document describes the format of an input catalogue for a galaxy simulation in Artificial sky tool (manual).

## Structure of the galaxy catalogue

The galaxy catalogue is FITS file with one or more table extensions. Every extension represents a galaxy class (type) like elliptical or spiral galaxy. Every row in the table describes parameters of a model for the class. Currently, only elliptical galaxies are implemented.

## The first extension

The first extension is dummy. It is recommend to have set HDUNAME = 'ARTGALAXY', even it is not currently used.

## ELLIPTICAL

This extension, identified by EXTNAME = 'ELLIPTICAL', contains parameters for specification of elliptical galaxies. Their profiles are based on Sérsic model.

ELLIPTICAL extension
Column | Description | Units
--- | --- | ---
RAJ2000 | Right Ascension of the centre | deg
DEJ2000 | Declination of the centre | deg
MUEFF | Surface magnitude in Reff | mag/arcsec2
REFF | Effective radius Reff | deg
PA | Position angle (top is zero) | deg
E | Eccentricity b/a |
SERSIC | Sérsic exponent |

## See Also

Artificial sky tool, manual.

artgalaxy.lst is a template of a galaxy catalogue; run `munipack fits --restore artgalaxy.lst` to make FITS itself.