A telescope control and scheduling system for the Gravitational-wave Optical Transient Observer
Martin J Dyer
备注:
344 pages, PhD Thesis (submitted 26 September 2019, awarded 10 January 2020), abstract and some images compressed for space (see https://etheses.whiterose.ac.uk/25648/ for original)
The detection of the first electromagnetic counterpart to a gravitational-wave signal in August 2017 marked the start of a new era of multi-messenger astrophysics. An unprecedented number of telescopes around the world were involved in hunting for the source of the signal, and although more gravitational-wave signals have been since detected, no further electromagnetic counterparts have been found.
In this thesis, I present my work to help build a telescope dedicated to the hunt for these elusive sources: the Gravitational-wave Optical Transient Observer (GOTO). I detail the creation of the GOTO Telescope Control System, G-TeCS, which includes the software required to control multiple wide-field telescopes on a single robotic mount. G-TeCS also includes software that enables the telescope to complete a sky survey and transient alert follow-up observations completely autonomously, whilst monitoring the weather conditions and automatically fixing any hardware issues that arise. I go on to describe the routines used to determine target priorities, as well as how the all-sky survey grid is defined, how gravitational-wave and other transient alerts are received and processed, and how the optimum follow-up strategies for these events were determined.
The GOTO prototype, situated on La Palma, saw first light in June 2017. I detail the work I carried out on the site to help commission the prototype, and how the control software was developed during the commissioning phase. I also analyse the GOTO CCD cameras and optics, building a complete theoretical model of the system to confirm the performance of the prototype. Finally, I describe the results of simulations I carried out predicting the future of the GOTO project, with multiple robotic telescopes on La Palma and in Australia, and how G-TeCS might be modified to operate these telescopes as a single, global observatory.
The Gravitational-wave Optical Transient Observer (GOTO) is a wide-field telescope project aimed at detecting optical counterparts to gravitational wave sources. The prototype instrument was inaugurated in July 2017 on La Palma in the Canary Islands. We describe the GOTO Telescope Control System (G-TeCS), a custom robotic control system written in Python which autonomously manages the telescope hardware and nightly operations. The system comprises of multiple independent control daemons, which are supervised by a master control program known as the "pilot". Observations are decided by a "just-…
The Gravitational-wave Optical Transient Observer (GOTO) is a wide-field telescope project focused on detecting optical counterparts to gravitational-wave sources. Each GOTO robotic mount holds eight 40 cm telescopes, giving an overall field of view of 40 square degrees. As of 2022 the first two GOTO mounts have been commissioned at the Roque de los Muchachos Observatory on La Palma, Canary Islands, and construction of the second node with two additional 8-telescope mounts has begin at Siding Spring Observatory in New South Wales, Australia. Once fully operational each GOTO mount will be netwo…
The discovery and subsequent study of optical counterparts to transient sources is crucial for their complete astrophysical understanding. Various gamma ray burst (GRB) detectors, and more notably the ground--based gravitational wave detectors, typically have large uncertainties in the sky positions of detected sources. Searching these large sky regions spanning hundreds of square degrees is a formidable challenge for most ground--based optical telescopes, which can usually image less than tens of square degrees of the sky in a single night. We present algorithms for optimal scheduling of such…
The Burst Observer and Optical Transient Exploring System (BOOTES) was first designed as an asset of autonomous telescopes that started to be deployed in 1998, taking 24 years to be fully developed around the Earth. Nowadays BOOTES has became a global network of robotic telescopes, being the first one present in all continents, as of 2022. Here we present the details of the network and review its achievements over the last two decades regarding follow-up observations of high-energy transient events. Moreover, considering the recent operations of neutrino and gravitational wave detectors, some …
We present a method for scheduling observations in small field-of-view transient targeted surveys. The method is based on maximizing the probability of detection of transient events of a given type and age since occurrence; it requires knowledge of the time since the last observation for every observed field, the expected light curve of the event, and the expected rate of events in the fields where the search is performed. In order to test this scheduling strategy we use a modified version of the genetic scheduler developed for the telescope control system RTS2. In particular, we present examp…
The Gravitational-wave Optical Transient Observer (GOTO) is an array of wide-field optical telescopes, designed to exploit new discoveries from the next generation of gravitational wave detectors (LIGO, Virgo, KAGRA), study rapidly evolving transients, and exploit multi-messenger opportunities arising from neutrino and very high energy gamma-ray triggers. In addition to a rapid response mode, the array will also perform a sensitive, all-sky transient survey with few day cadence. The facility features a novel, modular design with multiple 40-cm wide-field reflectors on a single mount. In June 2…
The Gravitational-wave Optical Transient Observer (GOTO) is a wide-field telescope project focused on detecting optical counterparts to gravitational-wave sources. GOTO uses arrays of 40 cm unit telescopes (UTs) on a shared robotic mount, which scales to provide large fields of view in a cost-effective manner. A complete GOTO mount uses 8 unit telescopes to give an overall field of view of 40 square degrees, and can reach a depth of 20th magnitude in three minutes. The GOTO-4 prototype was inaugurated with 4 unit telescopes in 2017 on La Palma, and was upgraded to a full 8-telescope array in 2…
How would observers differentiate Beacons from pulsars or other exotic sources, in light of likely Beacon observables? Bandwidth, pulse width and frequency may be distinguishing features. Such transients could be evidence of civilizations slightly higher than ourselves on the Kardashev scale.
The Gravitational-wave Optical Transient Observer (GOTO) data pipeline and workflow for transient discovery
Department of Physics University of Warwick(华威大学物理系);School of Physics and Astronomy University of Birmingham(伯明翰大学物理与天文学学院);Astrophysics Research Cluster School of Mathematical and Physical Sciences University of Sheffield(谢菲尔德大学数学与物理科学学院天体物理研究集群);Centre for Electronic Imaging School of Physical Sciences The Open University(开放大学理学院电子成像中心);Research Software Engineering University of Sheffield(谢菲尔德大学研究软件工程);School of Physics & Astronomy Monash University(蒙纳士大学物理与天文学院);Institute for Globally Distributed Open Research and Education (IGDORE)(全球分布式开放研究与教育研究所)
Across the soft gamma-ray regime: utilizing simultaneous detections in the Compton Spectrometer and Imager (COSI) and the Background and Transient Observer (BTO) to understand astrophysical transients
Scheduling follow-up observations of energetic transients with the neutrino target scheduler (NuTS)
Colorado School of Mines(科罗拉多矿业学院);Laboratoire Univers et Particules de Montpellier(蒙彼利埃宇宙与粒子实验室);University of Chicago(芝加哥大学);University of Iowa(爱荷华大学);NASA Goddard Space Flight Center(美国宇航局戈达德太空飞行中心);Columbia University(哥伦比亚大学)
Electromagnetic follow-up of gravitational wave detections is very resource intensive, taking up hours of limited observation time on dozens of telescopes. Creating more efficient schedules for follow-up will lead to a commensurate increase in counterpart location efficiency without using more telescope time. Widely used in operations research and telescope scheduling, mixed integer linear programming (MILP) is a strong candidate to produce these higher-efficiency schedules, as it can make use of powerful commercial solvers that find globally optimal solutions to provided problems . We detail …
The Burst Observer and Optical Transient Exploring System (BOOTES) is a network of telescopes that allows the continuous monitoring of transient astrophysical sources. It was originally devoted to the study of the optical emission from gamma-ray bursts (GRBs) that occur in the Universe. In this paper we show the initial results obtained using the spectrograph COLORES (mounted on BOOTES-2), when observing optical transients (OTs) of diverse nature.
Toward Autonomous Radio Follow-up of Multi-messenger Transients with RADAR: From Alert Parsing to Inference and Observation Scheduling
The University of Chicago(芝加哥大学);Argonne National Laboratory(阿贡国家实验室);Johns Hopkins University(约翰斯·霍普金斯大学);University of Illinois Urbana-Champaign(伊利诺伊大学厄巴纳-香槟分校)
The Gravitational-wave Optical Transient Observer (GOTO) is a wide-field telescope project focused on detecting optical counterparts to gravitational-wave sources. The GOTO Telescope Control System (G-TeCS) is a custom robotic control system which autonomously manages the GOTO telescope hardware and nightly operations. Since the commissioning the GOTO prototype on La Palma in 2017, development of the control system has focused on the alert handling and scheduling systems. These allow GOTO to receive and process transient alerts and then schedule and carry out observations, all without the need…
In order to identify the rapidly-fading, optical transient counterparts of gravitational wave (GW) sources, an efficient follow-up strategy is required. Since most ground-based optical observatories aimed at following-up GW sources have a telescope with a small field-of-view (FOV) as compared to the GW sky error region, we focus on a search strategy that involves dividing the GW patch into tiles of the same area as the telescope FOV to strategically image the entire patch. We present an improvement over the optimal telescope-scheduling algorithm outlined in Rana et al. (2016), by combining the…
LUMOS : Linear programming Utility for Multi-messenger Optical Scheduling
Astrophysics Research Institute, Liverpool John Moores University(利物浦约翰摩尔斯大学天体物理研究所);Department of Physics, Indian Institute of Technology Bombay(印度理工学院孟买分校物理系);School of Physics and Astronomy, University of Minnesota(明尼苏达大学物理与天文学学院);Astrophysics Science Division, NASA Goddard Space Flight Center(NASA戈达德太空飞行中心天体物理学科学部);Joint Space-Science Institute, University of Maryland(马里兰大学联合空间科学研究所)
Built in 2004, the Skynet robotic telescope network originally consisted of six 0.4 m telescopes located at the Cerro-Tololo Inter-American Observatory in the Chilean Andes. The network was designed to carry out simultaneous multi-wavelength observations of gamma-ray bursts (GRBs) when they are only tens of seconds old. To date, the network has been expanded to ~20 telescopes, including a 20 m radio telescope, that span four continents and five countries. The Campaign Manager (CM) is a new observing mode that has been developed for Skynet. Available to all Skynet observers, the CM semi-autonom…
A Multi-Level Validation and Traceability Framework for AI-Generated Telescope Scheduling Decisions
Yunnan Observatories, Chinese Academy of Sciences(云南天文台,中国科学院);University of Chinese Academy of Sciences(中国科学院大学);Key Laboratory of the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences(中国科学院天文结构与演化重点实验室);Yunnan Key Laboratory of Solar Physics and Space Science(云南太阳物理与空间科学重点实验室);Center for Astronomical Mega-Science, Chinese Academy of Sciences(中国科学院天文大科学中心)
We present development progress of the scheduler for the Son Of X-Shooter (SOXS) instrument at the ESO-NTT 3.58 meter telescope. SOXS will be a single object spectroscopic facility, consisting of a two-arms high-efficiency spectrograph covering the spectral range 350-2000 nanometer with a mean resolving power R$\approx$4500. SOXS will be uniquely dedicated to the UV-visible and near infrared follow up of astrophysical transients, with a very wide pool of targets available from the streaming services of wide-field telescopes, current and future. This instrument will serve a variety of scientifi…