Retrieves the lines of an atom or ion in a wavelength range from the NIST
Atomic Spectra Database (ASD): wavelengths, transition probabilities,
level energies and statistical weights, as needed by boltzmann()
and saha_boltzmann(). The data are downloaded on demand; they are
not distributed with specProc.
Arguments
- species
A character string naming the emitter in spectroscopic notation, such as
"Ca I"or"Ca II".- wavelength
A numeric vector of length 2: the wavelength range, in nm.
- with_aki
A logical: keep only the lines with a transition probability (
TRUE, default).- timeout
The download timeout, in seconds. Default is 120.
Value
A tibble with one row per line and columns species,
wavelength (nm), Aki (s\(^{-1}\)), fik (oscillator strength),
accuracy, Ei and Ek (lower and upper level energies, eV), gi
and gk (statistical weights), lower and upper (configuration,
term and J of the levels) and intensity (the relative intensity
listed by the ASD, as text).
Details
Wavelengths are in air between 200 and 2000 nm, and in vacuum outside
this range, as in the ASD. The observed wavelength is used when there is
one, the Ritz wavelength otherwise. Energies in brackets or with other
qualifiers are returned as they can be read as numbers; check the ASD
for such levels. The accuracy grade of the transition probability
(accuracy: AAA, AA, A+, A, B+, B, C+, C, D+, D, E) matters for plasma
diagnostics: prefer lines of grade B or better.
The results of a query are cached for the R session. Cite the database when you use these data:
Kramida, A., Ralchenko, Yu., Reader, J., and NIST ASD Team. NIST Atomic Spectra Database, https://physics.nist.gov/asd. National Institute of Standards and Technology, Gaithersburg, MD.
Examples
# \donttest{
# needs an internet connection
ca <- try(nist_lines("Ca II", wavelength = c(310, 400)))
if (!inherits(ca, "try-error")) ca
#> # A tibble: 7 × 12
#> species wavelength Aki fik accuracy Ei Ek gi gk lower upper
#> <chr> <dbl> <dbl> <dbl> <chr> <dbl> <dbl> <dbl> <dbl> <chr> <chr>
#> 1 Ca II 316. 3.10e8 0.93 C 3.12 7.05 2 4 3p6.… 3p6.…
#> 2 Ca II 318. 3.60e8 0.82 C 3.15 7.05 4 6 3p6.… 3p6.…
#> 3 Ca II 318. 5.80e7 0.088 C 3.15 7.05 4 4 3p6.… 3p6.…
#> 4 Ca II 371. 8.80e7 0.18 C 3.12 6.47 2 2 3p6.… 3p6.…
#> 5 Ca II 374. 1.7 e8 0.18 C 3.15 6.47 4 2 3p6.… 3p6.…
#> 6 Ca II 393. 1.47e8 0.682 C 0 3.15 2 4 3p6.… 3p6.…
#> 7 Ca II 397. 1.4 e8 0.33 C 0 3.12 2 2 3p6.… 3p6.…
#> # ℹ 1 more variable: intensity <chr>
# }