arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1002.4383astro-ph.HEastro-ph.GA
收藏

Vela-X脉冲星风星云的费米大面积望远镜观测

Fermi Large Area Telescope observations of the Vela-X Pulsar Wind Nebula

The Fermi LAT Collaboration, Pulsar Timing Consortium

摘要:

利用费米大天区望远镜(LAT)11个月的观测数据,对船帆座脉冲星PSR B 0833 -45的非脉冲窗口进行了伽马射线观测。这颗脉冲星位于直径为8度的船帆座超新星遗迹中,其中包含几个在无线电,X射线和伽马射线波段检测到的非热发射区域。LAT探测到的伽马射线辐射位于其中一个区域内,即脉冲星Vela-X以南2*3度的区域。LAT通量在空间上显著扩展,对于假设的径向对称均匀圆盘,最佳拟合半径为0.88 +/- 0.12度。该源的200 MeV至20 GeV LAT谱符合幂律,谱指数为2.41 +/- 0.09 +/- 0.15,100 MeV以上的积分通量为(4.73 +/- 0.63 +/- 1.32)* 10^{-7} cm^{-2} s^{-1}。第一个误差代表拟合参数的统计误差,而第二个是系统不确定性。详细的形态学和光谱分析给出了脉冲星风星云(PWN)系统的能量和磁场的强约束,并有利于两个不同的电子种群的情况。

英文摘要:

We report on gamma-ray observations in the off-pulse window of the Vela pulsar PSR B0833-45, using 11 months of survey data from the Fermi Large Area Telescope (LAT). This pulsar is located in the 8 degree diameter Vela supernova remnant, which contains several regions of non-thermal emission detected in the radio, X-ray and gamma-ray bands. The gamma-ray emission detected by the LAT lies within one of these regions, the 2*3 degrees area south of the pulsar known as Vela-X. The LAT flux is signicantly spatially extended with a best-fit radius of 0.88 +/- 0.12 degrees for an assumed radially symmetric uniform disk. The 200 MeV to 20 GeV LAT spectrum of this source is well described by a power-law with a spectral index of 2.41 +/- 0.09 +/- 0.15 and integral flux above 100 MeV of (4.73 +/- 0.63 +/- 1.32) * 10^{-7} cm^{-2} s^{-1}. The first errors represent the statistical error on the fit parameters, while the second ones are the systematic uncertainties. Detailed morphological and spectral analyses give strong constraints on the energetics and magnetic field of the pulsar wind nebula (PWN) system and favor a scenario with two distinct electron populations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑