Determine the magnetic-field inclination factor

Determine the magnetic-field inclination factor \(\Phi\) for the different regions of NGC6334I independently of polarization-model normalization, in order to separate magnetic-field inclination from grain-size and alignment effects.

Background

The realistic polarization model includes a factor Φ\Phi that represents the effect of magnetic-field inclination and its relation to turbulent depolarization. Because the observations do not directly determine this factor, the authors initially set Φ=1\Phi=1 and subsequently vary it to fit the data. This creates a degeneracy between the inferred maximum aligned-grain size and the three-dimensional magnetic-field orientation.

References

The value of \Phi is not known, but we can initially fix \Phi using the low-end values of S\approx 1{\circ} and taking P_{\rm mod}\approx P_{\rm mod,\, id}, yielding \Phi\approx 1.

— Magnetic Fields in Massive Star-forming Regions (MagMaR). XII. Radiative Torque Alignment and Disruption in NGC6334I  (2609.03458 - Rawat et al., 3 Sep 2026) in Section 4.3, “Realistic polarization model with B-field tangling/inclination”

Therefore, although we adopted the best-match $\Phi$ values based on the RMSEs, the effect of changes in the B-field inclination angle on the polarization fraction is difficult to distinguish from other contributing factors. And there is no direct measurement of this factor for the whole . Hence, this result should be interpreted with some caution.

— Magnetic Fields in Massive Star-forming Regions (MagMaR). XII. Radiative Torque Alignment and Disruption in NGC6334I  (2609.03458 - Rawat et al., 3 Sep 2026) in Section 5.4, “Evidence for bending of B-fields toward denser regions”