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Updated: Aug 3, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Summary
Relativistic winds impact neutron star spin-down. Soft gamma repeaters (SGRs) with episodic winds suggest magnetar fields, while continuous winds indicate lower fields, aiding age and magnetic field determination.
Area of Science:
- Astrophysics
- High-energy astrophysics
Background:
- Soft gamma repeaters (SGRs) are believed to be neutron stars with exceptionally strong magnetic fields (>10^14 G).
- Neutron star spin-down is influenced by dipole radiation and particle winds.
Purpose of the Study:
- To investigate the influence of relativistic winds on neutron star spin-down.
- To apply these findings to understand the properties of soft gamma repeaters (SGRs).
Main Methods:
- Derivation of a spin-down formula incorporating torques from dipole radiation and particle winds.
- Analysis of SGR 1806-20 as a case study, considering both continuous and episodic wind scenarios.
Main Results:
- A continuous particle wind (10^37 ergs s^-1) for SGR 1806-20 yields consistent pulsar age but a lower magnetic field (3x10^13 G).
- Episodic particle winds with a small duty cycle reconcile observed period derivatives with magnetar-strength fields and plausible ages.
Conclusions:
- The duty cycle of particle winds is crucial for determining the magnetic field strength and age of SGRs.
- Continuous monitoring of SGR periods can constrain wind properties, magnetic fields, and neutron star ages.
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