伽马射线脉冲星PSR J1836+5925的发现,为之前未被确认的EGRET源3EG J1835+5918提供动力,是费米大面积望远镜(LAT)的早期成就之一。PSR J 1836 +5925位于银河平面25度,是一颗173毫秒的脉冲星,特征年龄为180万年,自旋光度为1.1 $\times10^{34}$ erg s $^{-1}$,并且有很大的离峰发射分量,这使得它在已知的伽马射线脉冲星中非常不寻常。我们提出了一年的LAT数据的分析,包括更新的时间解决方案,详细的光谱结果和长期的光变曲线显示没有变化的迹象。没有证据表明周围有脉冲星风星云,离峰发射的光谱特征表明它可能是磁层。最近的XMM观测的X射线对应物的分析产生了一个详细的表征其光谱,其中,像Geminga,是一致的中子星,显示出磁层和热发射的证据。
英文摘要:
The discovery of the gamma-ray pulsar PSR J1836+5925, powering the formerly unidentified EGRET source 3EG J1835+5918, was one of the early accomplishments of the Fermi Large Area Telescope (LAT). Sitting 25 degrees off the Galactic plane, PSR J1836+5925 is a 173 ms pulsar with a characteristic age of 1.8 million years, a spindown luminosity of 1.1$\times10^{34}$ erg s$^{-1}$, and a large off-peak emission component, making it quite unusual among the known gamma-ray pulsar population. We present an analysis of one year of LAT data, including an updated timing solution, detailed spectral results and a long-term light curve showing no indication of variability. No evidence for a surrounding pulsar wind nebula is seen and the spectral characteristics of the off-peak emission indicate it is likely magnetospheric. Analysis of recent XMM observations of the X-ray counterpart yields a detailed characterization of its spectrum, which, like Geminga, is consistent with that of a neutron star showing evidence for both magnetospheric and thermal emission.
Precision Determination of Scintillation Screen Parameters from Annual Modulation Measurement of Pulsar Scintillation Arc Curvature with the FAST Telescope
South-Western Institute for Astronomy Research (SWIFAR), Yunnan University(西南天文研究所,云南大学);Xinjiang Astronomical Observatory, Chinese Academy of Sciences(中国科学院新疆天文台);Key Laboratory of radio Astronomy, Chinese Academy of Sciences(中国科学院射电天文重点实验室);Xinjiang Key Laboratory of radio Astrophysics(新疆射电天体物理重点实验室);National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University(北京师范大学前沿天文与天体物理研究所);Yunnan Observatories, Chinese Academy of Sciences(中国科学院云南天文台);Key Laboratory of Radio Astronomy and Technology, Chinese Academy of Sciences(中国科学院射电天文与技术重点实验室)
Interstellar Scintillation observations for PSR B0355+54
本文报道了我们用\emph{Kunming 40-m radio telescope}连续三个月监测PSR B 0355 $+$ 54在2.25 GHz的脉冲星闪烁现象的研究。我们测量了动态谱、二维关联函数和二级谱。在高信噪比($S/N\ge100$)观测中,我们发现了闪烁弧,这是很少使用这样一个小的望远镜观测。闪烁弧的亚微秒尺度宽度表明,散射屏上结构的横向尺度与AU尺寸一样紧凑。我们的监测还表明PSR B 0355 $+$ 54的闪烁带宽、时标和弧曲率随时间变化。合理的解释将需要调用多散射屏或多散射结构的情况下,不同的屏幕或射线路径主导的闪烁过程在不同的时期。
The Green Bank Telescope 350 MHz Drift-scan Survey I: Survey Observations and the Discovery of 13 Pulsars
2007年夏天,我们用绿岸望远镜在350兆赫的射频上进行了1191小时的“漂移扫描”脉冲星搜索观测。在这里,我们描述的调查设置,搜索程序,和发现和后续的时间13颗星。在这些新发现中,有一颗(PSR J1623-0841)是仅通过单脉冲发现的,两颗(PSR J1327-0755和J1737-0814)是毫秒脉冲星,另一颗(PSR J2222-0137)是轻度再循环脉冲星。PSR J1327-0755是一颗2.7 ms的脉冲星,DM为27.9 pc cm^{-3},轨道为8.7天,最小伴星质量为0.22太阳质量。PSR J1737-0814是一颗4.2 ms脉冲星,DM为55.3 pc cm^{-3},轨道为79.3天,最小伴星质量为0.06太阳质量。PSR J2222-0137是一颗32.8 ms的脉冲星,DM值非常低,为3.27 pc cm^{-3},轨道为2.4天,最小伴星质量为1.11太阳质量。它很可能是一个白矮星-中子星系统,或者是一个不寻常的低偏心率双中子星系统。在这项调查中发现的其他十个天体在Lynch et al. 2012的配套论文中报告。
Simulation of the orbit and spin period evolution of the double pulsars PSR J0737-3039 from their birth to coalescence induced by the gravitational wave radiation