Remanence magnetization time dependence

If the microscopic dwell times are all much larger than the measurement time, then one probes the system as a static distribution of its parameters in order to deduce the state in which the system was prepared, by its previous temperature, applied field, and structuro-chemical history. For example, this would correspond to a remanence magnetization measurement, in the absence of time or relaxation effects. Alternatively, one can consider that all the particles in the sample that have microscopic dwell times much larger than the measurement time form a subgroup or subsystem that has reliably preserved a subsystem-specific remanence signal. Since dwell times are highly temperature dependent (Eqn. 2), partial thermoremanence measurements are a powerful tool to reconstruct a rock s thermomagnetic history. 

Figure 23 Temperature dependence of the relaxation time of the magnetization of the chain compound [Co(hfac)2NITPhOMe] . The empty circles represents the data extracted from a.c. susceptibility while the triangles represents those extracted from the time decay of the remanent magnetization. The line corresponds to the best fit with the Arrhenius law with A = 152( 1)K and ro = 4( l) x 10 s.

F.4.3.2. Time Dependence. For a single particle an exponential decay of the remanent magnetization was predicted by Neel ... 

Figure G.2. Time dependence of the remanent magnetization at different temperatures for fine CrO, paticles. (Reproduced with permission from Ref. 370.)...

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