3C 58: A Pulsar Wind Nebula Whose Low Efficiency Sharpens the Age Question

This paper computes the energy, density and acceleration budgets of 3C 58 from a small set of adopted, published input values, using the relations stated in the Methods and a deposited script that reproduces every number. Timing gives a spin-down power of 2.69e+37 erg per second, a surface field of 3.6e+12 gauss and a characteristic age of 5.39e+03 years, several times the historical age, which is the formal statement of the tension. The nebula's X-ray luminosity is an efficiency of only 0.000744 of the spin-down power, two orders of magnitude below the Crab, so either most injected energy is stored invisibly or the injected total is smaller than the characteristic-age reading suggests. The calculation is a computation from stated assumptions, not a measurement, and each headline result is reported together with the diagnostic that tests whether the assumed evolutionary phase applies to this object.