2025/04/01 by Rahaman, Sk. Minhajur, Acharya, Sandeep Kumar, Beniamini, Paz +1 · 3 citations
#FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE)
paper · doi:10.48550/arxiv.2504.01125
The rare association of three persistent radio sources (confirmed PRS1 and PRS2, candidate PRS3) with repeating fast radio bursts (FRB 20121102A, 20190520B, 20201124A) offers a unique probe into their magneto-ionic environments. PRSs are attributed to synchrotron emission from relativistic charged particles of magnetar wind nebula (MWN) powered by spin-down magnetohydrodynamic wind or internal magnetic field decay. Using a multizone hydrodynamic model, we track MWN evolution to constrain magnetar progenitor properties. For PRS1 and PRS2, we find an equipartition radius Req ∼ 0.1 pc that is consistent with the radio scintillation estimates (> 0.03 pc) and radio imaging limits (<0.7 pc). This compact size favors low expansion speeds and large initial spin periods, Pi \gtrsim 10 ms, ruling out millisecond magnetar progenitors. Given Pi \gtrsim 10 ms, a current size of ∼ 0.1 pc, a supernova kinetic energy E_ SN ∼ 1050-1051 erg and an ejecta mass M ∼ 3-10 M\odot, the PRS age is t ∼ 10-102 yr. PRSs with t>20 years require an internal field (Bint ∼ 1016-1016.5 G) with a decay timescale td ∼ 10-102.5 yr. The slowest field decay (td,max ∼ 500 yr) favors sub-energetic supernovae (ESN ∼ 1050 erg) with massive ejecta (M \gtrsim 10 M\odot) and low ionization fraction (∼ 3% ). For the sub-energetic scenario for the confirmed PRSs, we predict a cooling break at 100-150 gigahertz at 20-40 μJy and self-absorption near 200 megahertz at 180 μJy. For PRS3, a rotation-powered MWN is viable only if t ∼ 10 yr; an inverted spectrum beyond 150 gigahertz would rule out this scenario.