论文标题
使用Chandra和更好的PSR J1813-1749的适当运动，光谱和时机
Proper motion, spectra, and timing of PSR J1813-1749 using Chandra and NICER
论文作者
论文摘要
PSR J1813-1749是已知的最能量旋转动力的脉冲星之一，产生了脉冲星风星云（PWN）和伽马射线和TEV发射，但其自旋周期仅在X射线中可测量。我们介绍了两个Chandra数据集的分析，这些数据集已被十年以上的数据分开，并且最近的数据分析了。 The long baseline of the Chandra data allows us to derive a pulsar proper motion mu_R.A.=-(0.067"+/-0.010") yr^-1 and mu_decl.=-(0.014"+/-0.007") yr^-1 and velocity v_perp~900-1600 km/s (assuming a distance d=3-5 kpc), although we cannot exclude a由于PWN的亮度结构的变化非常靠近Pulsar，对测得的脉冲星位置变化的贡献。我们使用吸收的功率定律对PWN和PULSAR光谱进行建模，并获得最佳拟合吸收NH =（13.1 +/- 0.9）X10^22 cm^-2，Photon Index Gamma = 1.5 +/- 0.1和0.3-10 Kev unx 〜5.4x10^34 erg/s（d/erg/s（d kem）= 1.1 = 1.2 = 1.2 = 1.2 = 1.2 = 1.2 = 1.2 = 1.2 = 1.2 lx〜9.3x10^33 erg/s（d/5 kpc）^2用于PSR J1813-1749。这些值不会在2006年至2016年的观察结果之间发生变化。从2019年开始，我们使用更好的观察结果来获得PSR J1813-1749的定时模型，旋转频率nu = 22.35 Hz，并且自旋频率时间派生时间派生时间=（-6.428 +/- 0.003）x10^-11^-11 Hz/s。我们还拟合了从2009 - 2012年开始的NU测量值和2019年值，并找到长期旋转速率nudot =（-6.3445 +/- 0.0004）x10^-11 Hz/s。我们推测，降低速率的差异是由于故障活动或发射模式切换引起的。
PSR J1813-1749 is one of the most energetic rotation-powered pulsars known, producing a pulsar wind nebula (PWN) and gamma-ray and TeV emission, but whose spin period is only measurable in X-ray. We present analysis of two Chandra datasets that are separated by more than ten years and recent NICER data. The long baseline of the Chandra data allows us to derive a pulsar proper motion mu_R.A.=-(0.067"+/-0.010") yr^-1 and mu_decl.=-(0.014"+/-0.007") yr^-1 and velocity v_perp~900-1600 km/s (assuming a distance d=3-5 kpc), although we cannot exclude a contribution to the change in measured pulsar position due to a change in brightness structure of the PWN very near the pulsar. We model the PWN and pulsar spectra using an absorbed power law and obtain best-fit absorption NH=(13.1+/-0.9)x10^22 cm^-2, photon index Gamma=1.5+/-0.1, and 0.3-10 keV luminosity Lx~5.4x10^34 erg/s (d/5 kpc)^2 for the PWN and Gamma=1.2+/-0.1 and Lx~9.3x10^33 erg/s (d/5 kpc)^2 for PSR J1813-1749. These values do not change between the 2006 and 2016 observations. We use NICER observations from 2019 to obtain a timing model of PSR J1813-1749, with spin frequency nu=22.35 Hz and spin frequency time derivative nudot=(-6.428+/-0.003)x10^-11 Hz/s. We also fit nu measurements from 2009-2012 and our 2019 value and find a long-term spin-down rate nudot=(-6.3445+/-0.0004)x10^-11 Hz/s. We speculate that the difference in spin-down rates is due to glitch activity or emission mode switching.
