Formation of multiscale structures in a self-gravitating dusty plasma with matter current

Area of Science:

• Astrophysical plasma physics
• Magnetohydrodynamics
• Gravitational dynamics

Background:

• Astrophysical plasmas exhibit complex magnetic-field structures.
• Self-gravitation and rotation are key factors in cosmic structure formation.
• Dust grains play a significant role in plasma dynamics.

Purpose of the Study:

• Investigate the formation of multiscale magnetic-field structures in rotating, self-gravitating dusty plasmas.
• Incorporate the gravitomagnetic field into a fluid model for astrophysical plasmas.
• Analyze the interplay of self-gravity, rotation, and electromagnetic forces on plasma self-organization.

Main Methods:

• Developed a three-component fluid model for dusty plasmas (electrons, ions, charged dust grains).
• Incorporated the gravitomagnetic field arising from mass currents in rotating objects.
• Derived a triple-curl Beltrami equilibrium characterized by three distinct spatial scales from a governing cubic equation.

Main Results:

• Identified three distinct spatial scales in the magnetic-field structures, determined by eigenvalues of a cubic equation.
• Demonstrated that self-gravitation, rotation, and electromagnetic interactions collectively influence these scales.
• Estimated comparable magnitudes of gravitational and electromagnetic forces on centimeter-sized dust grains in dense, rotating molecular clouds.

Conclusions:

• Rotation and gravity are pivotal in plasma self-organization, leading to multiscale magnetic structures.
• The derived model offers insights into processes relevant to star and cluster formation.
• Significant alterations in magnetic and flow-field profiles are expected for dust grains under these conditions.