Discovery of a glitch in the accretion- powered pulsar SXP 1062

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Serim M. M., Sahiner S., Cerri-Serim D., İNAM S. Ç., BAYKAL A.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, cilt.471, sa.4, ss.4982-4989, 2017 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 471 Sayı: 4
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1093/mnras/stx1771
  • Dergi Adı: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.4982-4989
  • Anahtar Kelimeler: accretion, accretion discs, stars: neutron, pulsars: individual: SXP 1062, X-rays: binaries, X-RAY SOURCES, SMALL-MAGELLANIC-CLOUD, VARIABLE SPIN-DOWN, VORTEX CREEP MODEL, NEUTRON-STAR, PARAMETER-ESTIMATION, TIMING OBSERVATIONS, SUPERNOVA REMNANT, PERIOD VARIATIONS, ORBITAL PERIOD
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

We present timing analysis of the accretion-powered pulsar SXP 1062, based on the observations of Swift, XMM-Newton and Chandra satellites covering a time span of about 2 yr. We obtain a phase coherent timing solution that shows that SXP 1062 has been steadily spinning down with a rate-4.29(7) x10(-14) Hz s(-1) leading to a surface magnetic field estimate of about 1.5 x 10(14) G. We also resolve the binary orbital motion of the system from X-ray data that confirms an orbital period of 656(2) d. On MJD 56834.5, a sudden change in pulse frequency occurs with Delta v = 1.28(5) x 10(-6) Hz, which indicates a glitch event. The fractional size of the glitch is Delta v/v similar to 1.37(6) x 10(-3) and SXP 1062 continues to spin-down with a steady rate after the glitch. A short X-ray outburst 25 d prior to the glitch does not alter the spin-down of the source; therefore, the glitch should be associated with the internal structure of the neutron star. While glitch events are common for isolated pulsars, the glitch of SXP 1062 is the first confirmation of the observability of this type of events among accretion-powered pulsars. Furthermore, the value of the fractional change of pulse frequency ensures that we discover the largest glitch reported up to now.