The emission process of Fast Radio Bursts (FRBs) remains unknown. We investigate whether the synchrotron maser emission from relativistic shocks in a magnetar wind can explain the observed FRB properties. We perform particleincell (PIC) simulations of perpendicular shocks in cold pair plasmas, checking our results for consistency among three PIC codes. We confirm that a linearly polarized Xmode wave is selfconsistently generated by the shock and propagates back upstream as a precursor wave. We find that at magnetizations σ ≳ 1 (i.e. ratio of Poynting flux to particle energy flux of the preshock flow) the shock converts a fraction $f_\xi ^{\prime } \approx 7 \times 10^{4}/\sigma ^2$ of the total incoming energy into the precursor wave, as measured in the shock frame. The wave spectrum is narrowband (fractional width ≲1−3), with apparent but not dominant linelike features as many resonances concurrently contribute. The peak frequency in the preshock (observer) frame is $\omega ^{\prime \prime }_{\rm peak} \approx 3 \gamma _{\rm s  u} \omega _{\rm p}$, where γsu is the shock Lorentz factor in the upstream frame and ωp the plasma frequency. At σ ≳ 1, where our estimated $\omega ^{\prime \prime }_{\rm peak}$ differs from previous works, themore »
 Award ID(s):
 1716567
 Publication Date:
 NSFPAR ID:
 10291263
 Journal Name:
 Monthly Notices of the Royal Astronomical Society
 Volume:
 499
 Issue:
 2
 Page Range or eLocationID:
 2884 to 2895
 ISSN:
 00358711
 Sponsoring Org:
 National Science Foundation
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