Stark Broadening of Al IV Spectral Lines
Round 1
Reviewer 1 Report
Comments for author File: 
Comments.pdf
Author Response
We thank to reviewer for careful reading of the manuscript and very useful comments and remarks
which improve our manuscript. Our answers are:
1) Line 17, “pressure” instead of “presure”
Corrected, thanks
2)Line 27, “derived” instead of “derrived”
Corrected, thanks
3) Could the authors explain or develop more the sentence, line 43-44 : “ it may be
particularly useful ... a more precise theoretical method.”?
Now this sentence is:
It may be particularly useful if we have not enough atomic energy levels for the adequate application of a more precise theoretical methods, since for the adequate application of MSE we need less data than for more sophysticated methods.
4) Line 54 and 55, “...N the electron density, T the temperature...”
Corrected, thanks.
5) Maybe, remove comments on 3kT/2E from the legend of table 1.
We removed this comment from the caption of Table 1.
6) Could the authors explain or develop more the sentence, line 60-62: “In some cases,
these tables ... described in ref (29).” ? The link with ref (29) in which a method is
proposed for calculating the radial matrix elements and the oscillator strengths for
non-hydrogenic atoms in the Coulomb approximation, is not clear for me.
Now this sentence is:
In some cases, these tables are not applicable, because the values are out of them, in particular
for higher principal quantum numbers, in such a case one can use the procedure described in Ref. \cite{Van79}, where the case of high principal quantum numbers is elaborated.
7) Could the authors explain how is estimated the percentage of theoretical errors of
your calculations?
We added a new paragraph and three references on the appropriate place:
From the first work in 1980 \cite{Di80}, MSE is applied and checked many times (see e.g. \cite{Di20} and references therein).
In order to test this method, selected experimental data for 36 multiplets (7 different ion species)
of triply charged ions were compared \cite{Di80} with theoretical linewidths. The averaged values of the ratios of measured
to calculated widths for doubly charged ions are 1.06 $\pm$ 0.32 and for triply charged ions
0.91 $\pm$ 0.42. Since for complex spectra the agreement may be worse, we assumed that the average accuracy is within the limits
of about $\pm$50\%, but it has been shown \cite{Po96, Po98} that the MSE approach, even in the case of emitters with complex spectra
(as e.g., Xe II and Kr II), gives very good agreement with experimental measurements (in the interval $\pm$30\%). For example, for
the 6s–6p transitions of Xe II the averaged ratio between the experimental and theoretical widths of the lines
is 1.15 $\pm$ 0.5 \cite{Po96}. Consequently, we assume that the average accuracy of the results obtained here for Al IV is not worse than 40\%.
Dimitrijevi\'{c}, M.S. Forty Years of the Applications of Stark Broadening Data Determined with the Modified Semiempirical Method. {\it Data} {\bf 2020}, {\it 5}, 73.
Popovi\'{c}, L.\v{C} ; Dimitrijevi\'{c}, M.S. Stark broadening of Xe II lines. {\it Astron. Astrophys. Suppl. Ser.} {\bf 1996}, {\it 116}, 359.
Popovi\'{c}, L.\v{C} ; Dimitrijevi\'{c}, M.S. Stark broadening parameters for Kr II lines from 5s - 5p transitions. {\it Astron. Astrophys. Suppl. Ser.} {\bf 1998}, {\it 127}, 295.
8) Line 75, “closest” instead of “closer”
Corrected, thanks
9) Line 76, “emphasizes” instead of “shows”
Corrected, thanks
10) Line 82, “widths” instead of “wdths”
Corrected, thanks
11) line 94, “presented” instead of “presnted”
Corrected, thanks
12) In table 2, why having chosen 80000K?
We added in the text:
since this temperature is closest to the middle of the investigated interval of temperatures.
13) line 101, “than” instead of “from”.
Corrected, thanks.
14) The multiplets are not correctly identified in the last paragraph of page 6. The values
94% and 12% correspond to 4p 2 [1/2] o –4d 2 [3/2] and not to 4s 2 [1/2] o –4p 2 [3/2] as
mentioned.
Corrected, thanks.
15) Line 130, “spectral” instead of “specrral”.
Corrected, thanks.
16) Line 137, isn’t it “log g=8” instead of “log g=4.5”?-
Corrected, thanks.
17) Same for line 141.
Corrected, thanks.
18) The first paragraph on page 8 refers to the article on zinc. A brief description of the
results of ref. (33) would make this article more fluid to read.
We rearanged this section so that the description of results of ref. (33) is first
19) Line 147, “illustrates” instead of “is a demonstration”.
Changed, thanks.
20) Line 172, “aluminum” instead of “zinc”.
Reviewer 2 Report
This is a well-written and interesting paper. Accurate accounting for Stark broadening of spectral lines plays an important role not only for plasma diagnostics, but also for radiation transport and overall energy balance in radiation-dominated systems. Computing pressure-broadened lineshapes in dense plasmas is a complex problem. Well-developed models exist for some transitions, e.g., K-shell lines in highly-charged ions. For transitions in multi-electron systems, simple semi-empirical models are frequently used. While being fast and easy to implement, these simple models may lack accuracy needed for detailed spectral simulations. The authors utilize modified semiempirical method to compute Stark widths for several transitions in Ne-like Al, the data that are important for astrophysical applications, for example in the analysis of visible spectra from atmospheres of A-type stars and white dwarfs. This approach is suitable for computing Stark broadening in complex multi-electron ions where adequate set of atomic data required for more rigorous calculations may not be easily available. The results of the calculations are presented in a tabulated form for a grid of plasma temperatures. The accuracy of the results is estimated to be very reasonable, providing significant improvement compared to simpler models. The authors plan to submit the data to the publicly available databases. This will provide an important resource for cross-checking consistency of other theoretical or experimental data on Stark widths. The formalism is outlined clearly and the results are presented well. Tables and figures are appropriate. I can recommend this paper for publication in its present form.Author Response
We are very grateful to the reviewer for positive opinion for our work.
Reviewer 3 Report
The authors compute the Stark broadening for various transitions of Al iV, and compare the results to astronomical observations (stellar observations). The method is sound and the results are useful. The English must be improved. I recommend publication.
Author Response
We are very grateful to the reviewer for positive opinion on our work. We improved English in the paper.
Round 2
Reviewer 1 Report
The authors have taken into account all the suggestions made by the reviewers. This new version of the manuscript deserves its publication in Universe.
