Investigating the role of magnetic fields in star formation using molecular line profiles
| Autor: | F. D. Priestley, Charles Yin, James Wurster |
|---|---|
| Přispěvatelé: | University of St Andrews. School of Physics and Astronomy |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
MHD
NDAS FOS: Physical sciences Field strength 01 natural sciences Molecular physics 0103 physical sciences Radiative transfer QB Astronomy 010303 astronomy & astrophysics formation [Stars] molecules [ISM] QC Solar and Stellar Astrophysics (astro-ph.SR) Astrophysics::Galaxy Astrophysics Astrochemistry QB Physics 010308 nuclear & particles physics Star formation Molecular cloud magnetic fields [ISM] Astronomy and Astrophysics Astrophysics - Astrophysics of Galaxies Supercritical fluid Magnetic field QC Physics Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) Magnetohydrodynamics Intensity (heat transfer) |
| ISSN: | 0035-8711 |
| Popis: | Determining the importance of magnetic fields in star forming environments is hampered by the difficulty of accurately measuring both field strength and gas properties in molecular clouds. We post-process three-dimensional non-ideal magnetohydrodynamic simulations of prestellar cores with a time-dependent chemical network, and use radiative transfer modelling to calculate self-consistent molecular line profiles. Varying the initial mass-to-flux ratio from sub- to super-critical results in significant changes to both the intensity and shape of several observationally important molecular lines. We identify the peak intensity ratio of N$_2$H$^+$ to CS lines, and the CS $J=2-1$ blue-to-red peak intensity ratio, as promising diagnostics of the initial mass-to-flux ratio, with N$_2$H$^+$/CS values of $>0.6$ ($5$) indicating subcritical (supercritial) collapse. These criteria suggest that, despite presently being magnetically supercritical, L1498 formed from subcritical initial conditions. 8 pages of text, 10 pages in total. Accepted in MNRAS |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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