Implications of a constant observed braking index for young pulsar's spindown

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The observed braking index nobs which had been determined for a few young pulsars, had been found to differ from the expected value for a rotating magnetic dipole model. Also, the observational jerk parameter, determined for two of these pulsars, disagree with the theoretical prediction mobs = 15 in both cases. We propose a simple model able to account for these differences, based on a growth of the "torque function" K = -(dot Omega)/(Omegaⁿ), under the constraint that nobs is a constant. We show that there is observational evidence supporting the latter hypotesis, and derive initial values for several physical quantities for the four pulsars whose nobs have been measured.