New observations of the cyclotron absorption feature in Hercules X–1
New observations of the cyclotron absorption feature in Hercules X–1
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DOI：
10.1038/346250a0
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发表时间：
1990-07
期刊：
影响因子：
64.8
通讯作者：
T. Mihara;K. Makishima;T. Ohashi;T. Sakao;M. Tashiro;F. Nagase;Y. Tanaka;S. Kitamoto;S. Miyamoto;J. Deeter;P. Boynton
中科院分区：
文献类型：
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作者：
T. Mihara;K. Makishima;T. Ohashi;T. Sakao;M. Tashiro;F. Nagase;Y. Tanaka;S. Kitamoto;S. Miyamoto;J. Deeter;P. Boynton
虽然人们普遍认为中子星出生时具有强烈的(1011-1013G)磁场1，2，然后逐渐衰减3，但对它们的磁场强度的测量仍然不确定。在发射X射线的双星脉冲星的特殊情况下，可以通过测量电子回旋共振引起的光谱特征的能量来直接估计场强。利用银河卫星观测站14，15，我们测量了1.24-S双星脉冲星大力神X-1的硬X射线谱中的回旋特征，能量分辨率比以前的观测4-9高得多。10-60keV的谱可以用一个简单的解析公式12，16，17来描述，这表明在∼34keV处有吸收特征，而不是在∼50keV处有发射特征。由此我们估算出HER X-1的表面磁场强度为(2.9±0.3)×1012G。
ALTHOUGH neutron stars are generally believed to be born with intense (1011–1013G) magnetic fields1,2, which then gradually decay3, measurements of their field strengths remain uncertain. In the special case of X-ray-emitting binary pulsars, a direct estimate of the field strength can be obtained by measuring the energy of spectral features that are due to electron cyclotron resonance4–13. With the Ginga satellite observatory14,15, we have measured a cyclotron feature in the hard X-ray spectrum of the 1.24-s binary pulsar Hercules X–1 with a much greater energy resolution than in previous observations4–9. The spectrum from 10–60 keV can be described with a simple analytical formula12,16,17, which indicates an absorption feature at ∼34 keV rather than an emission feature at ∼50keV. From this we estimate the surface magnetic field strength of Her X–1 to be (2.9±0.3) × 1012G.