3D Local Measurement of the Magnetic Field Strength Inside Martian Meteorite NWA 7034 by Polarimetric Neutron Imaging

We present a new method for paleomagnetic investigations, polarized neutron imaging, a non‐destructive magnetic imaging technique benefiting from the high penetration depth and spin of the neutron allowing spatial characterization of the magnetic field within a sample. We showcase the general capabilities of the technique by performing 3D vector tomography reconstructing the full magnetic field inside a 10 mm × 13 mm × 2 mm fragment of the remagnetized Martian meteorite NWA 7034. This was done in preparation for the Mars sample return mission where the orientation of samples on Mars is known. The magnetic field was measured with a spatial resolution of 215 μm and lower field bound of 0.5 mT mm.