Contribution of AGN to the Morphological Parameters of Their Host Galaxies up to Intermediate Redshifts of z ∼ 2

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I congratulate the authors of manuscript entitled "AGN contribution on the morphological parameters of their host galaxies up to intermediate redshifts of z ∼ 2" for this contribution. The paper is very well presented and written, with very consistent and interesting results. I did not find anything that may prevent its publication as it is now.

I only found some very minor typos that I request the authors to fix:

Page 8, line 266. It is said that "the contribution of the AGN is equal to or larger than 25%, 50%, and 25%, respectively." I believe that the third value corresponds to 75% and not 25%. Is that right?

Page 10, line 332. "... analysis for different ’magnitudes and redshifts’ (top to bottom) and AGN contributions". Why ’magnitudes and redshifts’  are between quotes?? Do the authors wanted to mean anything in particular? If not, please remove the quotes.

Page 17, line 509. "... Similar has been seen previously in [88], ..." I believe that the authors wanted to say "Similar results has been .." Please, correct if necessary.

Author Response

We sincerely thank the reviewer for the helpful and constructive comments. We have carefully addressed all points raised in the referee report, and corresponding changes are highlighted in bold in the manuscript.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Provided in the attached PDF. 

Comments for author File: Comments.pdf

Author Response

We sincerely thank the reviewer for the helpful and constructive comments. We have carefully addressed all points raised in the referee report, and corresponding changes are highlighted in bold in the manuscript.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The authors extend their previous work, in which they studied how a luminous point-like source in the center (mimicking the contribution of an active galactic nucleus, or AGN) affects measurements of six well-known morphological parameters. This time, they examine the effects in COSMOS-like conditions up to z~2. The methodological results are clearly presented and are more or less convincing. However, some sections could be improved. I suggest a minor revision with all my comments listed below:

 

1) Is the abstract size too large? Even after removing all numerals, it exceeds 200 words. I am okay with that, but if the editor suggests shrinking its size, I would like to see the shortened version.

 

2) On p. 2, "properties like stellar mass, colour, luminosity, star formation, nuclear activity, and environment" — suggest mentioning gas, too.

 

3) On p. 2, "although classification using the Sérsic index can sometimes be difficult," there is also an additional difficulty related to the inclusion of spiral arms in the decomposition. Perhaps 2024MNRAS.528.1276M and 2024MNRAS.527.9605C are worth mentioning here, too.

 

4) On page 2, it says, "Whereas X-ray detected AGN occupy all regions of the color-magnitude diagram and are located mainly in the green valley." Isn't this sentence self-contradictory?

 

5) Throughout the work, you select a 5%-75% AGN contribution. Is this choice motivated or more arbitrary? What are the chances of finding a galaxy with a luminosity contribution of more than 50% in these bands? Perhaps the work needs a word or two about this important topic. If these chances are small, then real diagrams, such as CABR vs. CCON, probably won't be affected that much by such a large addition to their luminosity.

 

6) On p. 4, how many objects are in each bin? This can be determined from Fig. 2, but it would be better to know the exact number.

 

7) On page 4, it says, "with a pixel scale of 0.09 arcsec, corresponding to COSMOS." Isn't it 0.03 arcsec/pix? For example, Mandelbaum et al. (2012) and many other sources

 

8) On page 6, it says, "New images have been generated by adding five different AGN contributions of 5%, 10%, 25%, 50%, and 75% to the total flux of the galaxy, which was measured with SExtractor." Since these galaxies are from SDSS, why not use the photometry provided by their catalogs? How motivated the use of Sextractor here?

 

9) p. 6: "All additional information is given in [38] and their Fig. A1." There is no A1 in this reference.

 

10) There are three ways to do morphological classification mentioned in the introduction. In this work, 2,251 galaxies were visually classified as elliptical, early-S, or late-S, and then their separation in diagrams was studied. But was this sample well-separated in the diagrams you studied in the first place? This should be mentioned.

 

11) Can the orientation of the galaxies play an important role in this analysis? This should be clarified.

 

12 )The same question applies to size, especially relative to the PSF.

 

13) I think the paper would benefit from a short description of each morphological parameter, similar to section 3.1 in [38], but shorter and probably only textual.

 

14) I'm not sure that the comparison between local (z~0) and distant (z>1) galaxies carried out in sections 4.1 and 4.2 is methodologically sound. Even if we properly recreate morphological dimming and take into account the K-correction, the evaluation of all morphological parameters is affected by very different signal-to-noise ratios, image resolution, and aperture size (as acknowledged by the authors on page 16). Can we be sure that such a comparison is meaningful?

 

15) p.8 “to or larger than 25%, 50%, and 25%” - typo

 

16) p.8 “When it is shifted towards higher values it means ... Similarly, when it is shifted towards lower values ...” - I don’t get this, why?

 

17) How much do morphological parameters vary within a given morphological class? Can the variance threshold of 20% be justified somehow?

 

18) On page 18, it is strange that the GINI vs. M20 separation of classes was found by other authors but not in this work. What could be the reason for that?

 

19) "ASYM and SMOOTH are very sensitive to noise and image properties and are measured for a much smaller fraction of the total sample." I don't understand this. What prevents us from using them, and why can't we evaluate them in more cases? This is especially interesting since, in previous works, the authors claimed that ASYM was found to be a very stable parameter.

Comments on the Quality of English Language

There are some typos in the text, such as ‘redshiftm’, ‘nucleci’, etc. I suggest using a spellchecker to avoid these mistakes.

Author Response

We sincerely thank the reviewer for the helpful and constructive comments. We have carefully addressed all points raised in the referee report, and corresponding changes are highlighted in bold in the manuscript.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

I recommend this manuscript for publication.