MOPTOP - prototyping a new approach to high time resolution, multi-wavelength optical polarimetry

光学偏振法是在许多其他空间无法确定的天文源中对物理和磁场几何形状的探测。极化现在在诸如耀变体、活动星系核、x射线双星和伽马射线暴（GRBs）等时变源中作为物理条件（例如磁场强度/有序/几何和相对论等离子体动力学）的关键诊断发挥主导作用。在这些高能量源中，偏振使天文学家能够在空间尺度上探测到直接成像观测永远无法达到的物理条件。在LJMU，我们率先将极化应用于时变源。本文提出了一种多波长、优化时间分辨光学偏振法（MOPTOP）的新概念。这项工作建立在2012年（1年）PRD计划的基础上，该计划开发了用于时域研究的多波段光学偏振计（RINGO3）。MOPTOP将该设计的新颖概念与新型，低成本，高灵敏度的sCMOS探测器和双光束设计相结合，开发出一种结合了宽，无混淆视野，最大灵敏度和低系统误差的概念。MOPTOP目前处于TRL 3（我们已经测试了设计的一个关键组件-即两个sCMOS相机的快速同步）。在本提案中，我们要求拨款约17.1万英镑，将仪器TRL增加到7（在望远镜上测试和运行的原型）。仪器灵敏度的提高将允许在2.0米级望远镜上获得19等（误差为2%）的光源。该设计还应具有更低的系统分配率（<0.1%），以便对弱偏振源有更大的效用，并具有4倍宽的视场，以便快速跟踪定位不良的瞬态源。原型将在2.0米的利物浦望远镜（拉帕尔马）和/或2.4米的NARIT望远镜（泰国）上进行测试。我们不认为该项目将产生可保护的知识产权，因此将使仪器设计完全公有，目的是鼓励将副本放置在世界各地的其他设施。

Optical polarimetry is a probe of physical and magnetic field geometries in many otherwise spatially unresolved astronomical sources. Polarization is now taking a leading role as a key diagnostic of physical conditions (for example magnetic field strength/order/geometry and relativistic plasma dynamics) in time variable sources such as blazars, active galactic nuclei, x-ray binaries and gamma ray bursts (GRBs). In these high energy sources, polarization allows astronomers to probe the physical conditions at spatial scales that will never be accessible to direct imaging observations. At LJMU we have led the application of polarization to time variable sources. Here we propose a programme to develop a new concept in multi-wavelength, optimized time resolved optical polarimetry (MOPTOP). The work builds on a 2012 (1 year) PRD programme which developed a multi-band optical polarimeter for time domain studies (RINGO3). MOPTOP combines novel concepts from that design with new, low-cost, high-sensitivity sCMOS detectors and a dual beam design to develop a concept that combines a wide, un-confused field of view with maximal sensitivity and low systematic errors.MOPTOP is currently at TRL 3 (we have tested one key component of the design - namely the fast synchronization of two sCMOS cameras). In this proposal we request funding of ~£171k to increase the instrument TRL to 7 (a prototype tested and operational on a telescope). The increased sensitivity of the instrument will allow access to sources down to 19th magnitude (at 2% error) on a 2.0 metre class telescope. The design should also have much lower systematics (<0.1%) allowing greater utility for weakly polarized sources, and a 4 times wider field of view enabling rapid follow-up of poorly localized transient sources. The prototype will be tested on the 2.0m Liverpool Telescope (La Palma) and/or the 2.4 metre NARIT telescope (Thailand). We do not envisage protectable IP will arise from the project and consequently will make the instrument design fully public domain, with the aim of encouraging copies to be placed on other facilities around the world.