The low-frequency radio eclipses of the black widow pulsar J1810+1744
The low-frequency radio eclipses of the black widow pulsar J1810+1744
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DOI：
10.1093/mnras/sty349
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发表时间：
2018-02
影响因子：
4.8
通讯作者：
E. J. Polzin;R. Breton;A. O. Clarke;V. Kondratiev;B. Stappers;J. Hessels;C. Bassa;J. Broderick;J. Grießmeier;C. Sobey;S. Veen;J. V. Leeuwen;P. Weltevrede
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文献类型：
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作者：
E. J. Polzin;R. Breton;A. O. Clarke;V. Kondratiev;B. Stappers;J. Hessels;C. Bassa;J. Broderick;J. Grießmeier;C. Sobey;S. Veen;J. V. Leeuwen;P. Weltevrede
我们对黑寡妇脉冲星J1810+1744的低频段食进行了观测和分析。利用2011年至2015年期间的低频阵列（LOFAR）和韦斯特博克综合射电望远镜观测，我们测量了日食周围通量密度，色散测量和散射的变化。高时间分辨率、同步波束形成和干涉成像LOFAR观测显示，在日食期间，脉冲和来自源的总通量同时消失，3σ上限为36 mJy（<脉冲星平均日食外通量密度的10%）。色散测量的变化是高度不对称的，这表明由于轨道运动，物质的尾部被扫回。的出口偏差是可变的时间尺度短于3.6小时的轨道周期，并指示cloudspeedmedium。在出口期间检测到的额外脉冲展宽通常小于脉冲星自旋周期的20%，没有证据表明脉冲散射超出波束形成数据的可检测性。日食在149 MHz的轨道上持续了0.13%的时间，显示出与频率有关，总持续时间的比例为Δ v ^-0.41 ± 0.03。结果进行了讨论的背景下，系统的物理参数，日食机制的检查显示回旋加速器同步加速器吸收作为最有可能的主要原因，虽然非线性散射机制不能定量排除。推断的质量损失率与在哈勃时间内完全蒸发伴星所需的平均速率相似。
We have observed and analysed the eclipses of the black widow pulsar J1810+1744 at low radio frequencies. Using LOw-Frequency ARray (LOFAR) and Westerbork Synthesis Radio Telescope observations between 2011 and 2015, we have measured variations in flux density, dispersion measure, and scattering around eclipses. High-time resolution, simultaneous beamformed, and interferometric imaging LOFAR observations show concurrent disappearance of pulsations and total flux from the source during the eclipses, with a 3σ upper limit of 36 mJy ( < 10 per cent of the pulsar's averaged out-of-eclipse flux density). The dispersion measure variations are highly asymmetric, suggesting a tail of material swept back due to orbital motion. The egress deviations are variable on time-scales shorter than the 3.6 h orbital period and are indicative of a clumpy medium. Additional pulse broadening detected during egress is typically < 20 per cent of the pulsar's spin period, showing no evidence of scattering the pulses beyond detectability in the beamformed data. The eclipses, lasting ∼ 13 per cent of the orbit at 149 MHz, are shown to be frequency-dependent with total duration scaling as ∝ ν^−0.41 ± 0.03. The results are discussed in the context of the physical parameters of the system, and an examination of eclipse mechanisms reveals cyclotron–synchrotron absorption as the most likely primary cause, although non-linear scattering mechanisms cannot be quantitatively ruled out. The inferred mass-loss rate is a similar order of magnitude to the mean rate required to fully evaporate the companion in a Hubble time.