Planetary Nebula Emission Line Catalog

Image of NGC2392 courtesy NASA, A. Fruchter & the STScI ERO Team

Welcome to the on-line version of the "Catalog of Relative Emission Line Intensities Observed in Planetary Nebulae" (ELCAT for short). This catalog contains all emission line fluxes that have been published in the astrophysical literature through May 1995. This document provides a way to browse and select for retrieval data from ELCAT. Both general information about ELCAT, and a summary of how the catalog is formatted, are available.

ELCAT Components:

Related Software:

Software is available for making use of the data in ELCAT for scientific research. The TABLES external package provides rich suite of facilities for merging, sorting, selecting, manipulating, and printing all or portions of ELCAT. The nebular package provides utilities for deriving electron temperatures, densities, and ionic abundances from the emission line fluxes. This software is layered on IRAF, which can be obtained from NOAO.

Organization of ELCAT

ELCAT is organized into 13 ASCII files (or 3 compressed ASCII files) containing the published intensities, and four ASCII files containing ancillary information. The intensities are split into files of roughly 0.5 MB (or less) in size for ease of retrieval, and are sorted on the object common name. A graphical breakdown of the entries by discovery catalog is available.

Column Headings for Table of Intensities

The intensities are in free-format ASCII tables. Each line of text is one row of the table, and corresponds to one measurement of the flux in one or more emission lines. Each row contains the following information:
  1. Nebula name
  2. Region code (may be a null string)
  3. Wavelength of the emission line (in Å)
  4. Ionic identification (e.g., [O III])
  5. Number of lines identified (N > 1 for a blend)
  6. Intensity
  7. Code for intensity scale (e.g. "H-beta" for I(H-beta) = 100)
  8. Boolean flag: interstellar extinction correction applied?
  9. Author code (see literature references)
  10. Host galaxy name (extra-Galactic PNs only)

Tables of Ancillary Data

The ancillary data is comprised of the objects list, which includes various common name aliases and descriptive information; explanations of the literature reference codes; explanations of the region codes, which may include any special notations from or comments about the original paper; and a list of discovery papers for planetary nebulae.

About ELCAT...

"A Catalog of Relative Emission Line Intensities Observed in Planetary Nebulae" was produced by James B. Kaler and Louise Browning (Univ. of Illinois), and Richard A. Shaw (Space Telescope Science Institute). ELCAT contains nearly 70,000 entries on 1020 objects, and is roughly 5.5 MB in size, including the ancillary information. An earlier version of this catalog (which also included diffuse nebulae) was published in hardcopy form by Kaler (1976, ApJS, 31, 1). A paper describing this updated version by Kaler, Shaw, & Browning appeared in PASP, 109, 289 in March 1997.

This project was funded by the NSF though various grants to the Univ. of Illinois, and by the NASA Astrophysics Data Program through grants NAG5-1400 to the Univ. of Illinois and NAG5-1432 to Space Telescope Science Institute.

ELCAT Home Page ELCAT Data ELCAT Errata

Copyright 1998, The Association of Universities for Research in Astronomy, Inc. All rights reserved.

Dick Shaw (

Last update: 24 Jan 2002