than 2% and the 1$\sigma$ continuum instrumental error is around 0.1%.\
The resulting Stokes [*I*]{} (intensity) image has an rms noise level $\sigma_{I}\approx$ 0.260 mJy beam$^{-1}$ and the Stokes [*Q*]{} and [*U*]{} (polarized intensity) images have rms noise levels $\sigma_{Q}\approx\sigma_{U}\approx$ 0.021 mJy beam$^{-1}$. All the maps generated have a 3$\sigma$ cut.

ALMA dust polarization analysis {#cont}
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Fig.\[dust\] presents the distribution of the dust continuum emission (Stokes [*I*]{}) toward the center of OH 231.8+4.2. The hourglass shape (also seen in Fig.\[Evectors\]) is obvious and extends over $\sim$8$\times$3. The eastern side of the distribution appears to be brighter than the western counterpart. We observe two major bright regions noted B and C in Fig.\[dust\] . The first bright section (B) is confined at the waist of the hourglass structure, with the brighter part on its eastern side, and shows a mean flux of 29$\pm$3 mJy beam$^{-1}$ with a peak intensity (P$_{\it{Int}}$ for [Stokes *I*]{} emission) of 74$\pm$8 mJy beam$^{-1}$. The latter, located at the coordinates $\alpha(2000)$=07$^{h}$42$^{m}$16$^{s}$92, $\delta(2000)=-14\degr\,42\arcmin\,50\farcs076$ is coincident with the position of the central star component QX PuP derived by @Dodson2018 and @SC2018 ($\alpha   (J2000)$=07$^{h}$42$^{m}$16$^{s}$915, $\delta (J2000)= -14\degr\,42\arcmin\,50\farcs06$). The other region (C) is located in the south-east with a mean 