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  4. Multicomponent photoionization modeling: Cloudy c23.01 vs c08.00

Multicomponent photoionization modeling: Cloudy c23.01 vs c08.00

MMC.
2025;
Volume 12, Number 2
: pp. 588–602
https://doi.org/10.23939/mmc2025.02.588
Received: February 01, 2025
Revised: May 12, 2025
Accepted: June 11, 2025

Melekh B. Ya., Koshmak I. O.  Multicomponent photoionization modeling: Cloudy c23.01 vs c08.00.  Mathematical Modeling and Computing. Vol. 12, No. 2, pp. 588–602 (2025)

Authors:
  1. B. Ya. Melekh
  2. I. O. Koshmak
1
Ivan Franko National University of Lviv
2
Ivan Franko National University of Lviv

We present a renewed wrapper for multicomponent photoionization modeling (MPhM) of the nebular environment (NebEn) surrounding star-forming regions, based on the new version (c23.01) of G. Ferland's code CLOUDY.  Our approach to MPhM of NebEn accounts for the internal structure of the HII region and its evolution driven by superwind expansion.  An evolutionary grid of NebEn MPhM was calculated using both the old (based on CLOUDY c08.00) and the newly developed MPhM wrappers.  The resulting ionization structures, emissivities of diagnostically important emission lines, and modeled spectra were compared to estimate the impact of a coding error related to Ly$\alpha$ line formation, present in the old version of CLOUDY, on the NebEn MPhM results.  Based on this comparison, conclusions were drawn regarding the reliability of MPhM results obtained using the older code version.

nebular environment
star-forming region
photoionization modeling
superwind models
  1. Osterbrock D. E., Ferland G. J.  Astrophysics of Gaseous Nebulae and Active Galactic Nuclei. Second Edition.  Saulito, California, University Science Book (2005).
  2. Ferland G. J.  Hazy, a Brief Introduction to Cloudy.  University of Kentucky, Physics Department Internal Report (2008).
  3. Koshmak I. O., Melekh B. Ya.  Modelling of emission of H II region with bubble-like structure inside.  Kinematics and Physics of Celestial Bodies.  29 (6), 257–268 (2013).
  4. Koshmak I. O., Melekh B. Ya.  Multicomponent simulation of emission of low-metalicity H II regions.  Kinematics and Physics of Celestial Bodies.  30 (2), 70–84 (2014).
  5. Koshmak I. O., Melekh B. Ya.  Modelling of H II region radiation surrounding the starburst knot taking into account the structures evolution formed by superwind.  Kinematics and Physics of Celestial Bodies.  33 (2), 39–54 (2017).
  6. Melekh B., Recchi S., Hensler G., Buhajenko O.  Photoionization analysis of chemodynamical dwarf galaxies simulations.  Monthly Notices of the Royal Astronomical Society.  450 (1), 111–127 (2015).
  7. Chevalier R. A., Clegg A. W.  Wind from a starburst galaxy nucleus.  Letters to Nature.  317, 44–45 (1985).
  8. Weaver R., McCray R., Castor J., Shapiro P., Moore R.  Interstellar bubbles. II. Structure and evolution.  The Astrophysical Journal.  218, 377–395 (1977).
  9. Atek H., Labbé I., Furtak L. J., et al.  Most of the photons that reionized the Universe came from dwarf galaxies.  Nature.  626, 975–978 (2024).
  10. Gunasekera Ch. M., van Hoof P. A. M., Chatzikos M., Ferland G. J.  The 23.01 Release of Cloudy.  Research Notes of the AAS.  7 (11), 246 (2023).
  11. Kozel R. V., Melekh B. Ya.  Transformation of energy distribution of ionizing radiation during penetrating very thin and dense envelope of nebular plasma.  Visnyk of the Lviv University. Series Physics.  44, 136–144 (2009), (in Ukrainian).
  12. Melekh B. Ya., Koshmak I. O., Kozel R. V.  The influence of stellar wind bubbles on the radiation ionizing field in the nebular objects.  Journal of Physical Studies.  15 (3), 3901 (2011).
  13. Koshmak I. O., Melekh B. Ya.  The primordial helium abundance determination using multicomponent photoionization modelling of low-metalicity H II regions.  Advances in Astronomy and Space Physics.  8 (1–2), 16–23 (2018).
  14. Tarter C. B.  Radiative Transfer in a Gas Excited by X-Rays.  Ph.D. Thesis, Cornell University.  28–10, 3983 (1967).
  15. Leitherer C., Schaerer D., Goaldader J. D., et al.  Starburst 99: Synthesis Models for Galaxies with Active Star Formation.  Astrophysical Journal Supplement series.  123, 3 (1999).
  16. Schaerer D., de Koter A., Schmutz W., Maeder A.  Combined stellar structure and atmosphere models for massive stars. I. Interior evolution and wind properties on the main sequence.  Astronomy and Astrophysics.  310, 837–848 (1996).
  17. Schaerer D., de Koter A., Schmutz W., Maeder A.  Combined stellar structure and atmosphere models for massive stars. II. Spectral evolution on the main sequence.  Astronomy and Astrophysics.  312, 475–495 (1996).
  18. Pauldrach A. W. A., Hoffmann T. L., Lennon M.  Radiation-driven winds of hot luminous stars. XIII. A description of NLTE line blocking and blanketing towards realistic models for expanding atmospheres.  Astronomy and Astrophysics.  375 (1), 161–195 (2001).
  19. Izotov Yu. I., Thuan T. X., Lipovetsky V. A.  The primordial helium abundance from a new sample of metal deficient blue compact galaxies.  The Astrophysical Journal.  435, 647–667 (1994).
  20. Thuan T. X., Izotov Yu. I.  High-ionization emission in metal-deficient blue compact dwarf galaxies.  The Astrophysical Journal.  161, 240–270 (2005).
  21. Pequignot D.  Workshop on model nebulae.  Publication de l'Observatoire de Meudon, Paris, ed. D. Pequignot (1986).
  22. Ferland G., Binette L., Contini M., et al.  The Analysis of Emission Lines.  Space Telescope Science institute Symposium Series, R. Williams & M. Livio, editors;  Cambridge, Cambridge University Press  (1995).
  23. Mathis J. S., Rumpl W., Nordsieck K. H.  The size distribution of interstellar grains.  The Astrophysical Journal.  217, 425–433 (1977).
  24. Koshmak I. O., Melekh B. Ya.  The role of dust in modelling the H{\sc ii} region emission with bubble-like structure inside.  Journal of Physical Studies.  17 (4), 4901 (2013).
  25. Castor J., McCray R., Weaver R.  Interstellar bubbles.  The Astrophysical Journal.  200, L107–L110 (1975).
  26. Melekh B., Buhajenko O., Koshmak I.  Photoionization analysis of chemodynamical dwarf galaxies simulations. II. Detailed calculation of diffuse ionizing radiation.  Monthly Notices of the Royal Astronomical Society.  532 (1), 524–537 (2024).