It is generally assumed that the magnetic fields of millisecond pulsars (MSPs) are $\sim 10^{8}$G. We argue that this may not be true and the fields may be appreciably greater. We present six evidences for this: (1) The $\sim 10^{8}$ G field estimate is based on magnetic dipole emission losses which is shown to be questionable; (2) The MSPs in low mass X-ray binaries (LMXBs) are claimed to have $< 10^{11}$ G on the basis of a Rayleygh-Taylor instability accretion argument. We show that the accretion argument is questionable and the upper limit $10^{11}$ G may be much higher; (3) Low magnetic field neutron stars have difficulty being produced in LMXBs; (4) MSPs may still be accreting indicating a much higher magnetic field; (5) The data that predict $\sim 10^{8}$ G for MSPs also predict ages on the order of, and greater than, ten billion years, which is much greater than normal pulsars. If the predicted ages are wrong, most likely the predicted $\sim 10^{8}$ G fields of MSPs are wrong; (6) When magnetic fields are measured directly with cyclotron lines in X-ray binaries, fields $\gg 10^{8}$ G are indicated. Other scenarios should be investigated. One such scenario is the following. Over 85% of MSPs are confirmed members of a binary. It is possible that all MSPs are in large separation binaries having magnetic fields $> 10^{8}$ G with their magnetic dipole emission being balanced by low level accretion from their companions.
On the connection between accreting X-ray and radio millisecond pulsars
多年来,人们已经认识到,在低质量X射线双星(LMXB)的质量转移的终端阶段应该导致吸积中子星的磁层膨胀,导致制动扭矩作用于旋转的脉冲星。因此,在发现射电毫秒双星(MSP)之后,这些双星如何在罗氏瓣退耦阶段(RLDP)之后保持其快速自旋就成了一个悖论(例如Ruderman et al. 1989)。在这里,我提出了一个解决这个所谓的“关断问题”,这是最近发现的结合二进制恒星演化模型与扭矩计算(陶里斯2012)。解决的办法是,在RLDP期间,脉冲星的自旋平衡被打破,因此它仍然是一个快速旋转的物体。我简要地讨论了这些发现,鉴于两个观察到的自旋分布在人口的吸积X射线毫秒双星(AXMSP)和无线电MSP。
Do all millisecond pulsars share a common heritage?
低质量X射线双星系统中中子星毫秒脉动的发现证实了毫秒射电双星与低质量X射线双星系统之间的联系。从那时起,从LMXB产生毫秒射电双星,然后由于偶极辐射而自旋下降的过程被认为是毫秒射电双星的“标准进化”。然而,是否所有观测到的毫秒射电暴都可以由LMXB产生的问题直到现在还没有得到定量的解决。标准的演化过程产生的毫秒周期(P)和自旋下降速率(Pdot)并不完全独立。毫秒级射电望远镜可能达到的P-Pdot值受到联合约束。为了检验观测到的毫秒射电天体是否是毫秒X射线天体(MSXP)的明确后代,我们制作了一张概率图,它代表了标准模型下毫秒射电天体的预期分布。我们以超过95%的置信度表明,在标准模型的框架内,所观测到的毫秒X射线天体不能产生具有高磁场的最快旋转毫秒射电天体,例如PSR B 1937 +21。
Discovery of Millisecond Pulsars in the Globular Cluster Omega Centauri
半人马座球状星团是银河系中质量最大、亮度最高的星团。$γ$射线源FL8 Y J1326.7 $-$ 4729与星团的核心重合,这导致人们猜测星团核心可能存在迄今未知的射电暴或湮灭性暗物质。在这里,我们报告发现五毫秒半人马座欧米茄以下的观测与帕克斯射电望远镜。其中四颗星的自转周期分别为4.1、4.2、4.6和6.8毫秒,第五颗星的自转周期为4.8毫秒,属于食双星系统,轨道周期为2.1小时。澳大利亚望远镜紧凑阵列拍摄的星团中心的深射电连续图像显示了一小部分紧凑的射电源,这使得其他的射电星可能正在等待发现。我们认为,毫秒级双星极有可能是$γ$射线的发射源。这些恒星的长期定时为探索星团的动力学和星际介质提供了机会。