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

光学偏振测量是对许多空间上无法分辨的天文源的物理和磁场几何形状的探测。极化现在正在发挥主导作用，作为一个关键的诊断物理条件（例如磁场强度/秩序/几何和相对论等离子体动力学）的时间变量源，如耀变体，活动星系核，X射线双星和伽马射线暴（GRBs）。在这些高能量源中，偏振使天文学家能够探测空间尺度上的物理条件，而这些空间尺度永远无法直接进行成像观测。在LJMU，我们领导了偏振在时变源中的应用。在这里，我们提出了一个方案，以开发一个新的概念，多波长，优化的时间分辨光学偏振（MOPTOP）。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（RINGO 3）。MOPTOP将该设计的新概念与新型、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视场、高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--两台sCMOS相机的快速同步）。在这项提案中，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）。该仪器灵敏度的提高将允许在2.0米级望远镜上获得低至19等的源（误差为2%）。该设计还应具有低得多的系统性（<0.1%），从而允许对弱极化源的更大效用，以及4倍宽的视场，从而能够快速跟踪局部化不良的瞬态源。原型将在2.0米利物浦望远镜（La Palma）和（或）2.4米NARIT望远镜（泰国）上进行测试。我们预计该项目不会产生可保护的知识产权，因此将使乐器设计完全公有领域，目的是鼓励将副本放置在世界各地的其他设施上。

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.