Be X射线双星

Be X射线双星是一种高质量X射线双星,由一颗中子星和一颗Be星组成。通常中子星会以一个广阔的椭圆轨道环绕着Be星,而Be星的星风亦多会形成一个与中子星轨道交错的平面。每当中子星与Be星的星风相遇时,大量气体便依附在中子星上。气体会下沉到中子星并产生一股强烈的X射线[1]

LSI+61°303

LSI+61°303,亦即周期性伽玛射线源CG135+01,有可能是这种双星的例子。其每26.496天便会发出无线电波可见光红外线的波长变动周期亦为26.5天。[2]其致密天体的质量未被准确测出,但推定它因其巨大质量并非中子星而是黑洞。[3]

英仙座X

英仙座X是由仙后座γ变星脉冲星组成的双星,其X射线周期较长和较稳定。但也观测到一些X射线的闪焰,相信是由于吸积盘的变动,但未有发现其与光学变动的关联。[4]

至1996年达Be X射线双星级别的20多个天体中惟LSI+61°303及英仙座X发出明显较高光度及频率的X射线(kT ≈ 10–20 keV,对比其他的kT ≤ 1 keV)。LSI+61°303亦发出强烈的无线电波,使其近似于其他短周期高质量X射线双星。[2]

参考

  1. ^ Reig, Pablo. Be/X-ray binaries. Astrophysics and Space Science. 2011, 332: 1. Bibcode:2011Ap&SS.332....1R. arXiv:1101.5036 . doi:10.1007/s10509-010-0575-8. 
  2. ^ 2.0 2.1 Taylor AR, Young G, Peracaula M, Kenny HT, Gregory PC. An X-ray outburst from the radio emitting X-ray binary LSI+61°303. Astron Astrophys. 1996, 305: 817–24. Bibcode:1996A&A...305..817T. 
  3. ^ Taylor AR, Young G, Peracaula M, Kenny HT, Gregory PC. An X-ray outburst from the radio emitting X-ray binary LSI+61°303. Astron. Astrophys. 1996, 305: 817–24. Bibcode:1996A&A...305..817T. 
  4. ^ Massi, M; Migliari, S; Chernyakova, M. The black hole candidate LS I +61°0303. Monthly Notices of the Royal Astronomical Society. 2017, 468 (3): 3689. Bibcode:2017MNRAS.468.3689M. arXiv:1704.01335 . doi:10.1093/mnras/stx778.