lte_lines: assessed atomic data for optical analyses of B stars

C.S. Jeffery, Armagh Observatory, College Hill, Armagh BT61 9DG, Northern Ireland
P.L. Dufton, School of Physics, Queens University Belfast, Belfast, Northern Ireland

For calculating model spectra of early-type helium stars in LTE, we maintain a database of atomic data for, mostly, blue-visual absorption lines of light elements. The data is sorted with one file for each ion.

For each absorption line included, the database includes the wavelength, oscillator strength, radiative, collisional and van der Waal's damping constants (where available), the excitation energy of the lower-level in the transition, the multplet number (from Moore's revised multiplet tables). A reference for each of the oscillator strengths and damping constants is also given. The database is dynamic, with new lines being added as required. Some vetting is applied to ensure that only the most reliable data are included. Consequently the database is quite dynamic, with corrections and updates being included at arbitrary times.

A combined linelist can be constructed for use (eg) with SPECTRUM by executing the C-Shell program lte_line. All the files necesary to run lte_line are available as a gzipped tar file. Usage should make reference to the original article describing this database (Jeffery C.S., 1991, Newsletter on 'Analysis of Astronomical Spectra', No. 16, p. 17), in addition to references to specific data sources.

2001 November

The linelists have been reformatted. Damping constants have been converted to natural gammas. Damping constants and oscillator strengths are now stored as logarithms. The conversion was carried out by Philip Dufton, QUB. Consequently the description by Jeffery (1991) is partially out of date as it refers to the units and format of the data.

A number of utilities used to convert various linelist formats have been developed over the years. These are provided here "as is" with no guarantees.

Information

FileHTMLContents
"read.me" file containing original ascii text for WWW pages
Description of format and contents of ion files
File to insert and mark the end of a linelist
List of references to atomic data stored in ion files
gzipped tar file

Linelists for individual ions

The number of lines in each file is given for each ion.

Ion I = 0 II = + III = ++ IV = +++
Helium He I
367
He I
2
Lithium Li I
2
Carbon C I
15
C II
60
C III
27
C IV
10
Nitrogen N II
220
N III
23
Oxygen O I
6
O II
262
O III
6
Neon Ne I
17
Ne II
33
Magnesium Mg II
12
Aluminium Al II
10
Al III
18
Silicon Si I
1
Si II
19
Si III
26
Si IV
14
Phosphor P II
24
P III
6
P IV
1
Sulphur S II
88
S III
32
Chlorine Cl II
33
Argon A II
96
Calcium Ca II
21
Titanium Ti II
45
Chromium Cr II
5
Iron Fe I
101
Fe II
59
Fe III
12
Nickel

Major sources

Programs

lte_line C-shell script to construct a composite linelist given specified ions
lte_conv A Fortan utility to convert old linelist to new format. It will work on both complete linelists (including the atomic data at the start and references at the end) or raw ion files (such as Ni2.d).

In fact spectrum is much more powerful than the B-star tag suggests. It may be used to model a wide variety of stellar spectra in LTE and HSE, providing they are warm enough not to contain molecules. Consequentky, more estensive linelists may be reuqired to construct genuinley useful synthetic spectra. There are many sources of atomic data; the following utilities enable these to be imcorporated with existing QUB linelists.
vald_qub A Fortran utility to convert linelists downloaded from the Vienna Atomic Line Database into the new QUB format.
synspec_qub A Fortran utility to convert linelists in SYNSPEC format into the new QUB format.
lte_select A Fortran utility to manipulate QUB-format linelists. It starts by reading in an optional initial linelist (QUB format) which will not be changed.
An additional linelist (QUB format) is read in, it may be in the form of a Hubeny list, sorted by wavelength, or in some other order. Individual lines may be selected using various criteria including one or more of the following:
wavelength region
ions
oscillator strength

Examples of use:
1. Starting with an assessed list (such as created by "lte_line"), add additional lines from large database (eg Kurucz & Petrymann)
2. Starting with a large database (eg Kurucz & Petrymann) build up a reduced list ion by ion


This page is maintained by:
Simon Jeffery (csj@star.arm.ac.uk)
Last modified: 13/11/01

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