A precessing magnetar model for GLEAM-X J162759.5-523504.3

We propose a precessing transient magnetar model for the recently discovered radio source GLEAM-X J162759.5-523504.3. We identify the observed period of $\sim 1$ ks as the precession period of the magnetar deformed due to its strong ($B_{\varphi }\sim {10}^{16}$ G) toroidal field. The resulting deformation of order ${10}^{-4}$ implies a spin period of $P_{\mathrm{s}}=0.1$ s. Assuming a strong dipole field of $B_{\mathrm{d}}\sim {10}^{14}$ G we predict a period derivative of ${\dot{P}}_{\mathrm{s}}\sim {10}^{-11}$ s/s. We also predict that the precession period of the magnetar can be observed in the hard X-ray band just as the other three galactic magnetars exhibit precession.