Future experiments seeking to measure the neutron electric dipole moment(nEDM) require stable and homogeneous magnetic fields. Normally theseexperiments use a coil internal to a passively magnetically shielded volume togenerate the magnetic field. The stability of the magnetic field generated bythe coil within the magnetically shielded volume may be influenced by a numberof factors. The factor studied here is the dependence of the internallygenerated field on the magnetic permeability $\mu$ of the shield material. Weprovide measurements of the temperature-dependence of the permeability of thematerial used in a set of prototype magnetic shields, using experimentalparameters nearer to those of nEDM experiments than previously reported in theliterature. Our measurements imply a range of $\frac{1}{\mu}\frac{d\mu}{dT}$from 0-2.7\%/K. Assuming typical nEDM experiment coil and shield parametersgives $\frac{\mu}{B_0}\frac{dB_0}{d\mu}=0.01$, resulting in a temperaturedependence of the magnetic field in a typical nEDM experiment of$\frac{dB_0}{dT}=0-270$~pT/K for $B_0=1~\mu$T. The results are useful forestimating the necessary level of temperature control in nEDM experiments.
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