In nearby star-forming clouds, amplification and dissipation of the magneticfield are known to play crucial roles in the star-formation process. Thestar-forming environment varies from place to place and era to era in galaxies.In the present study, amplification and dissipation of magnetic fields instar-forming clouds are investigated under different environments usingmagnetohydrodynamics (MHD) simulations. We consider various star-formingenvironments in combination with the metallicity and the ionization strength,and prepare prestellar clouds having two different mass-to-flux ratios. Wecalculate the cloud collapse until protostar formation using ideal andnon-ideal (inclusion and exclusion of Ohmic dissipation and ambipolardiffusion) MHD calculations to investigate the evolution of the magnetic field.We perform 288 runs in total and show the diversity of the density range withinwhich the magnetic field effectively dissipates, depending on the environment.In addition, the dominant dissipation process (Ohmic dissipation or ambipolardiffusion) is shown to strongly depend on the star-forming environment.Especially, for the primordial case, magnetic field rarely dissipates withoutionization source, while it efficiently dissipates when very weak ionizationsources exist in the surrounding environment. The results of the present studyhelp to clarify star formation in various environments.
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