RINGO3: a multi-colour fast response polarimeter
RINGO3: a multi-colour fast response polarimeter
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DOI：
10.1117/12.927000
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发表时间：
2012-09
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影响因子：
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通讯作者：
D. Arnold;I. Steele;S. Bates;C. Mottram;R. Smith
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文献类型：
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作者：
D. Arnold;I. Steele;S. Bates;C. Mottram;R. Smith
伽玛暴喷流包含快速运动的电子，这些电子将绕着磁力线盘旋。这会导致它们发射偏振的同步辐射。我们已经建立了一系列的偏振仪(Ringo和RINGO2)，通过测量来自伽玛暴的光在特定单一波长的偏振来研究这一问题。这些仪器安装在利物浦望远镜上，这是一个位于拉帕尔马的全机器人(即无人)望远镜，它对NASA雨燕任务等卫星的触发做出反应。这已经取得了巨大的成功，首次探测到了早期的光学偏振。此外，最近首次测量到了伽玛暴在喷流扩张时的光偏振变化。本文介绍了RINGO_3的设计和建造。这将是一台可以同时在三个波长进行观测的多色仪器。通过这样做，我们将能够毫不含糊地确定在爆发中偏振发射来自哪里。这将使我们能够区分三种可能性：(1)激波锋面产生的磁不稳定性，(2)视线效应和(3)在整个相对论流出过程中存在的大范围磁场。该仪器设计结合了快速旋转的宝丽来，特别设计的偏振不敏感二向色镜和三个电子倍增CCD相机，以1秒的时间分辨率提供同时的波长覆盖。
GRB jets contain rapidly moving electrons which will spiral around magnetic field lines. This causes them to emit polarized synchrotron emission. We have built a series of polarimeters (RINGO and RINGO2) to investigate this by measuring the polarization of optical light from GRBs at a certain single wavelength. The instruments are mounted on the Liverpool Telescope, which is a fully robotic (i.e. unmanned) telescope on La Palma which reacts to triggers from satellites such as the NASA SWIFT mission. This has had great success, with the first ever detections of early time optical polarization being made. In addition, the first measurements of the change in optical polarization from a GRB as the jet expands have recently been obtained. In this paper we describe the design and construction of RINGO3. This will be a multi-colour instrument that can observe simultaneously at three wavelengths. By doing so we will be able to unambiguously identify where in the burst the polarized emission is coming from. This will allow us to distinguish between three possibilities: (1) Magnetic instabilities generated in the shock front, (2) Line of sight effects and (3) Large-scale magnetic fields present throughout the relativistic outflow. The instrument design combines a rapidly rotating polaroid, specially designed polarization insensitive dichroic mirrors and three electron multiplying CCD cameras to provide simultaneous wavelength coverage with a time resolution of 1 second.