A period increase 100 times the reported limit leaves 32 s RMS in seven ILT J1101+5521 pulse times

We test the reported period-change limit for ILT J1101+5521 with its seven public radio pulse times. We keep the integer cycle count that reproduces the published residuals. We fit an exact model with a constant positive period derivative of 1.711e-9 s/s. This rate is 100 times the reported limit. We fit the reference time and period again. The residual root mean square (RMS) is 31.72 s. The largest absolute residual is 54.44 s. The constant-period fit leaves 26.20 s RMS. One early pulse and six late pulses span 2150.13 days. The six late pulses span only 12.12 days. The fitted timing parameters absorb most of the slow period-change signal. At the reported limit, the remaining signal has only 0.086 s RMS. Nearby integer cycle counts also give small residuals. This result tests the stated limit from residual size. It does not detect period change or give a new physical upper limit. A noise sensitivity calculation needs an assumed distribution for changes in pulse phase. We preserve the input data, source hashes, code, fit tables, figure, and a simulation with a fixed random seed. These files permit inspection and offline reproduction.

ILT J1101+5521 · long-period radio transients · pulse timing · period derivative · cycle count · public data · white dwarf binary · reproducible analysis