MHD modeling of the molecular filament evolution

Cover Page

Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription or Fee Access

Abstract

We perform numerical magnetohydrodynamic (MHD) simulations of the gravitational collapse and fragmentation of a cylindrical molecular cloud with the help of the FLASH code. The cloud collapses rapidly along it’s radius without any signs of fragmentation in the simulations without magnetic field. The radial collapse of the cloud is stopped by the magnetic pressure gradient in the simulations with parallel magnetic field. Cores with high density form at the cloud’s edges during further evolution. The core densities are n ≈ 1.7×108 and 2×10-7 cm–3 in the cases with initial magnetic field strengths B = 1.9×10-4 and 6×10-4 G, respectively. The cores move toward the cloud’s centre with supersonic speeds |vz| = 3.6 and 5.3 km/s. The sizes of the cores along the cloud’s radius and cloud’s main axis are dr = 0.0075 pc and dz = 0.025 pc, dr = 0.03 pc and dz = 0.025 pc, respectively. The masses of the cores increase during the filament evolution and lie in range of ≈(10-20)Me. According to our results, the cores observed at the edges of molecular filaments can be a result of the filament evolution with parallel magnetic field.

Full Text

Restricted Access

About the authors

I. M. Sultanov

Chelyabinsk State University

Author for correspondence.
Email: syltahof@yandex.ru
Russian Federation, Chelyabinsk

S. A. Khaibrakhmanov

Saint Petersburg State University; Chelyabinsk State University; Ural Federal University

Email: syltahof@yandex.ru
Russian Federation, Saint Petersburg; Chelyabinsk; Yekaterinburg

References

  1. P. André, J. Di Francesco, D. Ward-Thompson, S.-I. Inutsuka, R. E. Pudritz, and J. E. Pineda, Protostars and Planets VI, edited by H. Beuther, R. S. Klessen, C. P. Dullemond, and T. Henning, (Tucson: University of Arizona Press, 2014), p.27.
  2. A. E. Dudorov and S. A. Khaibrakhmanov, Open Astronomy 26(1), 285 (2017).
  3. V. Konyves, P. André, A. Men’shchikov, P. Palmeirim, et al., Astron. and Astrophys. 584, id. A91 (2015).
  4. D. Ward-Thompson, K. Pattle, P. Bastien, R. S. Furuya, et al., Astrophys J. 842(1), id. 66 (2017).
  5. A. Hacar, S. E. Clark, F. Heitsch, J. Kainulainen, G. V. Panopoulou, D. Seifried, and R. Smith, Protostars and Planets VII, ASP Conf. Ser. 534, Proc. of a conference held 10–15 April 2023 at Kyoto, Japan; edited by Shu-ichiro Inutsuka, Y. Aikawa, T. Muto, K. Tomida, and M. Tamura (San Francisco: Astron. Soc. Pacific, 2023), p. 153.
  6. P. Bastien, Astron. and Astrophys. 119(1), 109 (1983).
  7. L.K. Dewangan, L.E. Pirogov, O.L. Ryabukhina, D. K. Ojha, and I. Zinchenko, Astrophys. J. 877(1), id. 1 (2019).
  8. S. Chandrasekhar and E. Fermi, Astrophys. J. 118, 116 (1953).
  9. J. S. Stodolkiewicz, Acta Astronomica 13, 30 (1963).
  10. J. Ostriker, 140, 10⁵6 (1964).
  11. Shu-ichiro Inutsuka and S. M. Miyama, 480, Astrophys. J. 681 (1997).
  12. Y. Shimajiri, P. André, N. Peretto, D. Arzoumanian, E. Ntormousi, and V. Konyves, Astron. and Astrophys. 672, id. A133 (2023).
  13. O.L. Ryabukhina, M. S. Kirsanova, C. Henkel, and D. S. Wiebe, Monthly Not. Roy. Astron. Soc. 517(4), 4669 (2022).
  14. D. Seifried and S. Walch, Monthly Not. Roy. Astron. Soc. 452(3), 2410 (2015).
  15. A.E. Dudorov and S. A. Khaibrakhmanov, Astrophys. Space Sci. 352(1), 103 (2014).
  16. A. E. Dudorov and Yu. V. Sazonov, Nauchnye Informatsii 63, 68 (1987).
  17. B. Fryxell, K. Olson, P. Ricker, F. X. Timmes, et. al., Astrophys. J. Suppl. 131, 273 (2000).
  18. B. van Leer, J. Comput. Phys. 32(1), 101 (1979).
  19. J. Barnes and P. Hut, Nature 324(6096), 446 (1986).
  20. C. Federrath, R.S. Klessen, L. Iapichino, and J.R. Beattie, Nature Astron. 5, 365 (2021).

Supplementary files

Supplementary Files
Action
1. JATS XML
Download
2. Fig. 1. Distribution of fiber density in the x – z plane in the GD calculation at time moments t = 0 (a), 0.8tff (b), 1tff (c).

Download (113KB)
Indexing metadata
3. Fig. 2. Distribution of density (color fill) and magnetic field lines (black lines with arrows) of the fiber in the x – z plane in the MHD-1 calculation at times t = 0 (a), 1tff (b), 1.28tff (c).

Download (159KB)
Indexing metadata
4. Fig. 3. Distribution of density and magnetic field lines of the fiber in the x – z plane in the MHD-2 calculation at time moments t = 0 (a), 1tff (b), 1.28tff (c), 1.9tff (d).

Download (191KB)
Indexing metadata
5. Fig. 4. Panel (a): z-axis fiber density profiles for MHD calculations at times t = 0, 1.28tff and 1.9tff . Panel (b): z-axis vz velocity profiles for MHD calculations at times t = 1.28tff and t = 1.9tff .

Download (181KB)
Indexing metadata
6. Fig. 5. Distribution of density (color fill), velocity fields (green arrows) and magnetic field lines (black lines with arrows) in the region of core formation in the MHD-1 calculation at times t = 1tff (a) and 1.28tff (b).

Download (344KB)
Indexing metadata
7. Fig. 6. Distribution of density (color fill), velocity fields (green arrows) and magnetic field lines (blue isolines) in the region of core formation in the MHD-2 calculation at times t = 1tff (a), 1.28tff (b), 1.9tff (c).

Download (224KB)
Indexing metadata

Copyright (c) 2024 The Russian Academy of Sciences