Rotation-powered pulsars and spin-down inference
Neutron-star pulsars have rotating magnetized stellar remnants whose emission can sweep past the observer.
Key knowledge
Neutron-star pulsars have rotating magnetized stellar remnants whose emission can sweep past the observer. For a rotation-powered model with constant moment of inertia I, E_rot=IΩ²/2=2π²I/P² and rotational energy loss is −dE_rot/dt=4π²IṖ/P³. This inferred power is distinct from luminosity measured in one observing band. Under constant PṖ and negligible initial period, the characteristic age is τ_c=P/(2Ṗ).
Values and equations
E_rot=2π²I/P²; L_spin=4π²IṖ/P³; τ_c=P/(2Ṗ)
- E_rot
- rotational energy at constant moment of inertia J
- I
- moment of inertia about the rotation axis kg m²
- P,τ_c
- spin period and conditional characteristic age s
- Ṗ
- intrinsic time derivative of period s s⁻¹
- L_spin
- inferred rotational energy-loss rate W
Conditions and scope
- P>0 and intrinsic Ṗ>0 for the stated spin-down estimate; correct timing for orbital and kinematic effects. I depends on stellar structure and the neutron-star equation of state.
- The age estimate requires a constant braking law with PṖ constant and P_initial much smaller than P; it is not a universal measured age. Accreting pulsars and magnetically powered sources can have other energy supplies; radio-emission microphysics is not completely settled.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Read rotating-beam/magnetosphere discussion and actual rotational-energy, derivative and characteristic-age derivation. Independently differentiated at constant I and integrated constant PṖ to retain the initial-period qualification. Excluded dated fastest/heaviest pulsars, universal EOS exclusions, fixed neutron-star mass/radius and identifying observed radio power with all spin-down power.
2026-10-10 · Independent AI editorial review: All44 exact root-authored compact records, equations/variable units/conditions and140 origin edges accepted after independently reading final6/18 with bounded primary bodies and matching prior38/122 scientific fingerprints unchanged. Exact claim/edge review is distinct from combined inventory scope and separate CLE26 approval; no entire cited books or old-corpus experimental revalidation is asserted. Receipt: cosmos-completion-independent-content-and-inventory-review.1.
Entry details
Permanent link to this entry ↗- Record identity
- uni-cosmos-pulsar-rotational-energy
- Revision
- core.1
- Structured reference record
- University core expansion