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arXiv 0910.4707astro-ph.HEastro-ph.GA
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费米大天区望远镜对毫秒双星的探测

Detections of millisecond pulsars with the Fermi Large Area Telescope

Lucas Guillemot

摘要:

费米天文台于2008年6月11日发射。它拥有\emph{Large Area Telescope}(LAT),对20 MeV到300 GeV以上的$γ$射线光子敏感。当LAT开始活动时,在$γ$射线中发现了9个年轻而充满活力的恒星。在发射前,LAT至少预测了几十颗脉冲星的探测。LAT还允许研究毫秒微扰(MSP),在费米之前,从未在$γ$射线中发现过。本论文首先介绍了LAT的脉冲星计时活动,与大型射电望远镜和X射线望远镜合作,允许高灵敏度脉冲搜索。此外,它导致准均匀覆盖的银河系MSP,使搜索脉动LAT数据为这个人口的恒星不受\emph{a priori}偏见。我们提出了一个搜索这些对象的LAT数据中的脉动。第一次,八个星系MSP已被检测到脉冲$γ$射线发射超过100兆电子伏的来源。此外,还发现了几个未来检测的好候选者。类似的对球状星团MSP的搜索至今还没有成功。通过比较相位对准的$γ$射线和射电光变曲线以及光谱形状,得出结论:它们的$γ$射线发射与正常的类星体相似,可能产生于外磁层。这一发现表明,许多未解决的$γ$射线源是未知的MSP。

英文摘要:

The Fermi observatory was launched on June 11, 2008. It hosts the \emph{Large Area Telescope} (LAT), sensitive to $γ$-ray photons from 20 MeV to over 300 GeV. When the LAT began its activity, nine young and energetic pulsars were known in $γ$ rays. At least several tens of pulsar detections by the LAT were predicted before launch. The LAT also allowed the study of millisecond pulsars (MSPs), never firmly detected in $γ$ rays before Fermi. This thesis first presents the pulsar timing campaign for the LAT, in collaboration with large radiotelescopes and X-ray telescopes, allowing for high sensitivity pulsed searches. Furthermore, it lead to quasi-homogeneous coverage of the galactic MSPs, so that the search for pulsations in LAT data for this population of stars was not affected by an \emph{a priori} bias. We present a search for pulsations from these objects in LAT data. For the first time, eight galactic MSPs have been detected as sources of pulsed $γ$-ray emission over 100 MeV. In addition, a couple of good candidates for future detection are seen. A similar search for globular cluster MSPs has not succeeded so far. Comparison of the phase-aligned $γ$-ray and radio light curves, as well as the spectral shapes, leads to the conclusion that their $γ$-ray emission is similar to that of normal pulsars, and is probably produced in the outer-magnetosphere. This discovery suggests that many unresolved $γ$-ray sources are unknown MSPs.

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。

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