The variable X-ray source 1E 1547.0-5408 was identified by Gelfand & Gaensler (2007) as a likely magnetar in G327.24-0.13, an apparent supernova remnant. No X-ray pulsations have been detected from it. Using the Parkes radio telescope, we discovered pulsations with period P = 2.069 s. Using the Australia Telescope Compact Array, we localized these to 1E 1547.0-5408. We measure dP/dt = (2.318+-0.005)e-11, which for a magnetic dipole rotating in vacuo gives a surface field strength of 2.2e14 G, a characteristic age of 1.4 kyr, and a spin-down luminosity of 1.0e35 ergs/s. Together with its X-ray characteristics, these rotational parameters of 1E 1547.0-5408 prove that it is a magnetar, only the second known to emit radio waves. The distance is ~9 kpc, derived from the dispersion measure of 830 pc/cc. The pulse profile at a frequency of 1.4 GHz is extremely broad and asymmetric due to multipath propagation in the ISM, as a result of which only approximately 75% of the total flux at 1.4 GHz is pulsed. At higher frequencies the profile is more symmetric and has FWHM = 0.12P. Unlike in normal radio pulsars, but in common with the other known radio-emitting magnetar, XTE J1810-197, the spectrum over 1.4-6.6 GHz is flat or rising, and we observe large, sudden changes in the pulse shape. In a contemporaneous Swift X-ray observation, 1E 1547.0-5408 was detected with record high flux, f_X(1-8 keV) ~ 5e-12 ergs/cm^2/s, 16 times the historic minimum. The pulsar was undetected in archival radio observations from 1998, implying a flux < 0.2 times the present level. Together with the transient behavior of XTE J1810-197, these results suggest that radio emission is triggered by X-ray outbursts of usually quiescent magnetars.
Magnetar-like X-ray Bursts from an Anomalous X-ray Pulsar
反常X射线脉冲星(AXP)是一类罕见的X射线脉冲星,其能量来源一直是一个令人困惑的问题。与其他更好理解的X射线星体不同,AXP不能由旋转或来自双星伴星的吸积提供动力,因此被称为“异常”。"AXP的旋转和辐射特性与另一类奇异物体--软伽马重复器(SGR)的旋转和辐射特性惊人地相似。然而,SGR的定义属性,即它们的低能量伽马射线和X射线爆发,迄今为止还没有在AXP中看到。SGR被认为是“磁星”,由超高磁场衰变提供能量的年轻中子星。AXP是磁星的说法一直存在争议。在这里,我们报告的发现,从AXP 1 E 1048-5937的方向,两个X射线爆发,有许多性质类似的SGR爆发。这些事件意味着AXP和SGR之间的密切关系,两者都是磁星。
X-ray Bursts from the Transient Magnetar Candidate XTE J1810-197
我们发现了四个X射线爆发,记录与罗西X射线定时探测器正比计数器阵列之间的2003年9月和2004年4月,我们表明,起源于瞬态磁星候选人XTE J1810-197。爆发形态包括一个短尖峰或多个尖峰,每个尖峰持续约1 s,随后是延长的发射尾部,其中XTE J1810-197的脉冲通量明显较高。突发尖峰可能与脉冲最大值相关,具有0.4%的随机相位分布的机会概率。爆发谱最适合于温度为4-8 keV的黑体,比持续X射线发射硬得多。在这些爆发之后的X射线拖尾期间,温度随着通量下降而迅速冷却,在最初的爆发峰值之后保持恒定的发射半径。在最亮的X射线尾部,我们探测到一条12.6 keV的窄发射线,其等效宽度为1.4 keV,偶然出现的概率小于4 x 10^-6。这些爆发的时间和光谱特征与1 E 1048.1-5937观测到的爆发和1 E 2259+586观测到的爆发子集非常相似,因此XTE J1810-197被确定为候选磁星。从这三个对象检测到的爆发是足够相似的彼此,但显着不同,从软伽马中继器看到的,他们可能代表了一个新的类别的爆发从候选人的磁星独家(迄今为止)的异常X射线脉冲星样源。
Magnetars: Structure and evolution from p-star models
P星是由处于$β$平衡的上夸克和下夸克与色磁凝聚体中的电子组成的致密星。我们讨论了具有超强偶极磁场的p-星,在文献中被称为磁星。我们表明,软γ射线中继器和异常的$X$ -射线散射可以理解我们的理论。我们找到了一个定义明确的标准来区分旋转动力的磁共振。我们表明,毛刺,在我们的磁星是由磁耗散效应在内核中触发的,解释了静态发射和爆发的软伽马射线中继器和异常$X$ -射线中继器。我们解释了SGR 1900+14的制动故障和AXP 1 E 2259+586的正常故障。我们讨论并解释了所观察到的硬度比和强度之间的反相关性。在我们的磁星理论中,我们能够定量地解释伽马射线中继星和异常$X$射线中继星的光变曲线。特别是我们解释了2002年6月18日来自AXP 1 E 2259+586的巨大爆发后令人困惑的光变曲线。