AtLL Logo Lines Levels News Instructions Documentation Contents Downloads

Atomic Line List v3.00b4 – Lines

Royal Observatory of Belgium ROB Logo
University of Kentucky UK Logo

This is a beta version of the next release of the Atomic Line List. It has not been been fully tested and is likely to be modified without prior notice. It is being offered for testing purposes. Please report any problems with the content or the interface.

This is a compilation of approximately 1.72 million allowed, intercombination and forbidden atomic transitions with wavelengths in the range from 0.6 Å to 1000 µm. It's primary intention is to allow the identification of observed atomic absorption or emission features. The wavelengths in this list are all calculated from the difference between the energy of the upper and lower level of the transition (except for hydrogenic lines, which are a weighted average of all the fine structure components). Only a very limited attempt has been made to include observed wavelengths.

When attempting to identify an observed line, usually many possible candidates can be found in this list. In order to facilitate narrowing down the number of possible identifications a selection tool is presented which allows imposing, apart from the wavelength, several additional criteria.

The current development of the atomic line list is described in van Hoof, P.A.M., 2018, Galaxies, 6, 63. Please cite this paper when you use any data from this list.

The atomic line list has undergone extensive development in the past years. The software generating the line list, as well as the program doing the line selection for the web page have been completely rewritten. The primary goal of this work will be to make the list complete for all elements, as far as data are available. The second goal is to add more transition probability data from additional sources. See the News tab on the navigation bar for more detailed information.

Selection Criteria

All fields in the request form have default values and may be left unspecified

Wavelength range:

(e.g. 6500-6600, or 6545+/-1, the "-" or "+/-" symbols are optional)
(multiple queries, each on a separate line, are allowed)
Wavelength Unit:   Type:
Radial velocity: vrad (in km/s) cosmological redshift z
A positive value means that the observed wavelength typed above
is redshifted w.r.t. the laboratory wavelengths in the output.
Min. relative wavl. accuracy:
Upper limit in percent.

(e.g. C II, or C II-IV, or C, or C-O; query is not case sensitive;
multiple lines of input are allowed)
Minimum line strength:   Type:
Lines without atomic data: include exclude
Minimum abundance:   Depl. factor:
Logarithmic number density, relative to log(H) = 12.
Lower level energy range:   Unit:

Transition types:  All Types  Nebular  Select:  E1  IC  M1  E2  M2  E3

Transitions from auto-ionizing levels:  Suppress  Show

Customize Output

Output format (Check each item you want included in the output):
Wavelength accuracy
Transition type
Angular momentum: as J as g combine with term
Transition probability: as Aki as gkAki as fik as S as log(gf)
Transition probability uncertainty
Level energies
plain html latex
Use fixed width columns

Version 3.00b4 of the line list was created: Jul 21, 2021.

  Contact Legal Credits
The Atomic Line List is licensed under CC BY 4.0