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arXiv · 2507.15010

Wide Area Linear Optical Polarimeter Control Software

Abstract

The WALOPControl software is designed to facilitate comprehensive control and operation of the WALOP (Wide Area Linear Optical Polarimeter) polarimeters, ensuring safe and concurrent management of various instrument components and functionalities. This software encompasses several critical requirements, including control of the filter wheel, calibration half-wave plate, calibration polarizer, guider positioning, focusers, and 4 concurrent CCD cameras. It also manages the host telescope and dome operations while logging operational parameters, user commands, and environmental conditions for troubleshooting and stability. It provides a user-friendly graphical user interface, secure access control, a notification system for errors, and a modular configuration for troubleshooting are integral to the software's architecture. It is accessible over the internet with the backend developed using NodeJS and ExpressJS, featuring a RESTful API that interacts with a MongoDB database, facilitating real-time status updates and data logging. The frontend utilizes the React.JS framework, with Redux for state management and Material UI for the graphical components. The system also allows for automatic observations based on user-defined schedules. A Continuous Integration and Continuous Deployment (CI CD) pipeline ensures the software's reliability through automated testing and streamlined deployment. The WALOPControl software is a key component of the PASIPHAE (Polar-Areas Stellar Imaging in Polarimetry High Accuracy Experiment) project, which aims to study the dust and magnetic field of the Milky Way by observing the polarization of starlight.

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John A. Kypriotakis, Bhushan Joshi, Dmitry Blinov, Sebastian Kiehlmann, Ramya M. Anche, Ioannis Liodakis, Myrto Falalaki, Tuhin Ghosh, Eirik Gjerløw, Siddharth Maharana, Nikolaos Mandarakas, Georgia V. Panopoulou, Katerina Papadaki, Vasiliki Pavlidou, Timothy J. Pearson, Vincent Pelgrims, Stephen B. Potter, Chaitanya V. Rajarshi, A. N. Ramaprakash, Anthony C. S. Readhead, Raphael Skalidis, Konstantinos Tassis. 2025-07-20. Wide Area Linear Optical Polarimeter Control Software. https://arxiv.org/abs/2507.15010

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