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arXiv · 2405.18923

The BlackGEM telescope array I: Overview

Paul J. Groot·S. Bloemen·P. Vreeswijk·J. van Roestel·P. G. Jonker·G. Nelemans·M. Klein-Wolt·R. Le Poole·D. Pieterse·M. Rodenhuis·W. Boland·M. Haverkorn·C. Aerts·R. Bakker·H. Balster·M. Bekema·E. Dijkstra·P. Dolron·E. Elswijk·A. van Elteren·A. Engels·M. Fokker·M. de Haan·F. Hahn·R. ter Horst·D. Lesman·J. Kragt·J. Morren·H. Nillissen·W. Pessemier·A de Rijke·G. Raskin·L. H. A. Scheers·M. Schuil·S. T. Timmer·L. Antunes Amaral·E. Arancibia-Rojas·I. Arcavi·N. Blagorodnova·S. Biswas·R. Breton·H. Dawson·P. Dayal·S. De Wet·C. Duffy·S. Faris·M. Fausnaugh·A. Gal-Yam·S. Geier·A. Horesh·C. Johnston·R. A. D. Wijnands·D. Modiano·G. Katusiime·C. Kelley·A. Kosakowski·T. Kupfer·G. Leloudas·O. Mogawana·J. Munday·J. A. Paice·F. Patat·I. Pelisoli·G. Ramsay·P. T. Ranaivomanana·R. Ruiz-Carmona·V. Schaffenroth·S. Scaringi·F. Stoppa·R. Street·H. Tranin·M. Uzundag·S. Valenti·M. Veresvarska·M. Vuckovic·H. C. I. Wichern·R. A. M. J. Wijers·E. Zimmerman
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Abstract

The main science aim of the BlackGEM array is to detect optical counterparts to gravitational wave mergers. Additionally, the array will perform a set of synoptic surveys to detect Local Universe transients and short time-scale variability in stars and binaries, as well as a six-filter all-sky survey down to ~22nd mag. The BlackGEM Phase-I array consists of three optical wide-field unit telescopes. Each unit uses an f/5.5 modified Dall-Kirkham (Harmer-Wynne) design with a triplet corrector lens, and a 65cm primary mirror, coupled with a 110Mpix CCD detector, that provides an instantaneous field-of-view of 2.7~square degrees, sampled at 0.564\arcsec/pixel. The total field-of-view for the array is 8.2 square degrees. Each telescope is equipped with a six-slot filter wheel containing an optimised Sloan set (BG-u, BG-g, BG-r, BG-i, BG-z) and a wider-band 440-720 nm (BG-q) filter. Each unit telescope is independent from the others. Cloud-based data processing is done in real time, and includes a transient-detection routine as well as a full-source optimal-photometry module. BlackGEM has been installed at the ESO La Silla observatory as of October 2019. After a prolonged COVID-19 hiatus, science operations started on April 1, 2023 and will run for five years. Aside from its core scientific program, BlackGEM will give rise to a multitude of additional science cases in multi-colour time-domain astronomy, to the benefit of a variety of topics in astrophysics, such as infant supernovae, luminous red novae, asteroseismology of post-main-sequence objects, (ultracompact) binary stars, and the relation between gravitational wave counterparts and other classes of transients

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Paul J. Groot, S. Bloemen, P. Vreeswijk, J. van Roestel, P. G. Jonker, G. Nelemans, M. Klein-Wolt, R. Le Poole, D. Pieterse, M. Rodenhuis, W. Boland, M. Haverkorn, C. Aerts, R. Bakker, H. Balster, M. Bekema, E. Dijkstra, P. Dolron, E. Elswijk, A. van Elteren, A. Engels, M. Fokker, M. de Haan, F. Hahn, R. ter Horst, D. Lesman, J. Kragt, J. Morren, H. Nillissen, W. Pessemier, A de Rijke, G. Raskin, L. H. A. Scheers, M. Schuil, S. T. Timmer, L. Antunes Amaral, E. Arancibia-Rojas, I. Arcavi, N. Blagorodnova, S. Biswas, R. Breton, H. Dawson, P. Dayal, S. De Wet, C. Duffy, S. Faris, M. Fausnaugh, A. Gal-Yam, S. Geier, A. Horesh, C. Johnston, R. A. D. Wijnands, D. Modiano, G. Katusiime, C. Kelley, A. Kosakowski, T. Kupfer, G. Leloudas, O. Mogawana, J. Munday, J. A. Paice, F. Patat, I. Pelisoli, G. Ramsay, P. T. Ranaivomanana, R. Ruiz-Carmona, V. Schaffenroth, S. Scaringi, F. Stoppa, R. Street, H. Tranin, M. Uzundag, S. Valenti, M. Veresvarska, M. Vuckovic, H. C. I. Wichern, R. A. M. J. Wijers, E. Zimmerman. 2024-11-22. The BlackGEM telescope array I: Overview. https://doi.org/10.1088/1538-3873%2Fad8b6a

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