Electron-Impact Ionization of Carbon

Round 1

Reviewer 1 Report

The authors present ionization cross sections in collision between electron and carbon atom using the classical trajectory Monte Carlo method. Total cross sections are benchmarked against the reported experimental data and the predictions of numerically intensive theoretical methods as well as pioneering calculations for this collision system.

This research work can be published in Atoms, after few corrections:

·       The reference 7 is cited before reference 6, please correct (swap the reference 6 & 7).

·       In formula 2, […]1 => […]-1        (1=> -1).

·       In line 164, it’s written Kim [16,17], it must be: Kim [16] and Kim and Delsclaux [17].

·       At line 340, the year of the reference 20 is wrong, please correct.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The work of Bachi et al. presents electron-impact ionization cross sections for carbon atom using the classical trajectory Monte Carlo method. This work provides hitherto unknown information about the transient time and fraction of collision events, would be helpful in fusion plasma research. However, substantial modifications are required. Here are the critical points about the paper:

（1）    Eqs. (1) and (2) are incorrect, see Ref. [13]. 

（2）    The calculation parameters presented in Table I, where are they from. Authors should supply a reference.

（3）    Eq. (8), (B/R) should be (R/B).

（4）    “E” was missed in Eq. (10) compared to Eq. (9), please add an explanation or comment.

（5）    higher energies are desired for fusion application, 1 keV -> 10 keV?

（6）    Contributions from 1s orbital was omitted, authors should explain the reason behind.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

The authors present new results on theoretical investigation of electron impact ionization for the carbon atom. The classical trajectory Monte Carlo method is used to calculate ionization cross sections. The calculations include the 2s and 2p orbitals. The data presented are up to 1000 eV energies. Three different approaches are used for comparison to experimental data. A good agreement to measurements of the used approach is obtained by multiplying the theoretical cross sections by energy dependent factors. The presented results could be important in further studies for understanding fundamental physical processes. In my view, this paper can be published, but I suggest some minor corrections to be made:

1) Authors are incorrect when they declare that the previous theoretical studies have been limited to energies lower than 100 eV. The scaled distorted wave approximation was previously used to analyze the ionization cross sections for the carbon atom for all 5 levels of the ground configuration up to impacting energies of 1000 eV [AA 620 A188]. The same approach was successfully used to study ionization process in the N atom [AA 659 A11], Si atom [ADNDT 135 101363]. Therefore, comparison of the direct and indirect ionization processes with the previous calculations has to be added to the paper.

2) Explain how contribution from the excitation-autoionization process is obtained in the current work.

3) Eq. (3): explain how the number of ionization events and total number of trajectories are calculated.

4) Eq. (7): the k parameter is used on the right hand side while the same parameter is missing on the left hand side.

5) Explain in more detail: “From the classical point of view, and in contrast to the prediction of quantum mechanics, atoms or ions with two or more bound electrons autoionize without the need of any external agent.”

 

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

can be accepted for publication now