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Does PSR J1417-4402 system behave as a Redback?

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 نشر من قبل Maria Alejandra De Vito
 تاريخ النشر 2018
  مجال البحث فيزياء
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We study the present evolutionary status of the binary system containing the 2.66 ms pulsar PSR J1417-4402 in a 5.4 day orbit. This is the pulsar in the original source 3FGL J1417.5-4402, that has undergone a transition from X-ray state to a pulsar state, just like some redbacks did. The system has many characteristics similar to redback pulsars family, but is on a much wider orbit. We show that close binary evolution including irradiation feedback driven by the luminosity due to accretion onto the neutron star component of the pair, and evaporation due to pulsar emission, is able to account for the masses of the components and the photometric data of the donor star. The tracks leading to the present PSR J1417-4402 are degenerate within a range of parameters, suggesting that the {it same} physics invoked to explain the redback/black widows groups leads to the formation of much wider orbit systems, outside the redback region limits.



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