Magnetic Field Morphology and Star Formation Efficiency in Protostellar Cores: An ALMA Polarimetric Analysis

Authors

Keywords:

Star formation, Magnetic fields, Molecular clouds, Collapse regulation, Interstellar medium, Hub-filament, Feedback, Polarization

Abstract

We present an observational study of magnetic field structure and star formation efficiency (SFE) in a sample of 26 protostellar cores using dust polarization data obtained with the Atacama Large Millimeter/submillimeter Array. The sample is composed primarily of low-mass star-forming systems, allowing a focused investigation of magnetic regulation at core scales. Magnetic field strengths are estimated using the Davis-Chandrasekhar-Fermi method, while SFE is derived from literature-based gas and stellar mass measurements. The results show that magnetic field strengths span over an order of magnitude, while SFE extends from moderate to high values, with several sources approaching unity. No single monotonic relationship is observed between magnetic field strength and SFE; instead, a structured distribution emerges. Magnetic field morphology plays a significant role in shaping this behavior: hourglass configurations are associated with relatively stronger fields and lower efficiencies, whereas turbulent and non-axisymmetric morphologies extend toward higher SFE values. These findings indicate that, at protostellar core scales, magnetic fields influence but do not uniquely determine star formation efficiency. Instead, SFE reflects the combined effects of magnetic field geometry, turbulence, and localized feedback processes. This study provides observational constraints on the role of magnetic fields in regulating collapse and disk formation in low-mass star-forming environments.

Author Biographies

Jemima N. Ogwo

Department of Physics, Abia State University, Uturu

PROFESSOR

Emenike Nwaokoro

Department of Industrial Physics,  Abia State University, Uturu.

DR

Chinedu O. Dike

Department of Physics, Alex Ekwueme Federal University, Ndufu Alike

Mr.

Prince O. Orji

Department of Physics and Astronomy, University of Nigeria, Nsukka

DR

Dimensions

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Published

2026-06-29

How to Cite

Okezuonu, P. C., Ogwo, J. N., Nwaokoro, E., Dike, C. O., & Orji, P. O. (2026). Magnetic Field Morphology and Star Formation Efficiency in Protostellar Cores: An ALMA Polarimetric Analysis. Nigerian Journal of Physics, 35(3), 197-212. https://doi.org/10.62292/njp.v35i3.2026.568

Issue

Vol. 35 No. 3 (2026): Nigerian Journal of Physics - Vol. 35 No. 3

Section

Articles
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Copyright (c) 2026 Patrick C. Okezuonu, Jemima N. Ogwo, Emenike Nwaokoro, Chinedu O. Dike, Prince O. Orji

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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

How to Cite

Okezuonu, P. C., Ogwo, J. N., Nwaokoro, E., Dike, C. O., & Orji, P. O. (2026). Magnetic Field Morphology and Star Formation Efficiency in Protostellar Cores: An ALMA Polarimetric Analysis. Nigerian Journal of Physics, 35(3), 197-212. https://doi.org/10.62292/njp.v35i3.2026.568