The GRANDMA network in preparation for the fourth gravitational-wave observing run

Jean-Paul Richard Kneib, Xiao Wang, Jieping Zhu
SPIE-INT SOC OPTICAL ENGINEERING, 2022
Conference paper

GRANDMA is a world-wide collaboration with the primary scientific goal of studying gravitational-wave sources, discovering their electromagnetic counterparts and characterizing their emission. GRANDMA involves astronomers, astrophysicists, gravitational-wave physicists, and theorists. GRANDMA is now a truly global network of telescopes, with (so far) 30 telescopes in both hemispheres. It incorporates a citizen science programme (Kilonova-Catcher) which constitutes an opportunity to spread the interest in time-domain astronomy. The telescope network is an heterogeneous set of already-existing observing facilities that operate coordinated as a single observatory. Within the network there are wide-field imagers that can observe large areas of the sky to search for optical counterparts, narrow-field instruments that do targeted searches within a predefined list of host-galaxy candidates, and larger telescopes that are devoted to characterization and follow-up of the identified counterparts. Here we present an overview of GRANDMA after the third observing run of the LIGO/VIRGO gravitational-wave observatories in 2019 - 2020 and its ongoing preparation for the forthcoming fourth observational campaign (O4). Additionally, we review the potential of GRANDMA for the discovery and follow-up of other types of astronomical transients.

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Jean-Paul Richard Kneib, Xiao Wang, Jieping Zhu
SPIE-INT SOC OPTICAL ENGINEERING, 2022
Conference paper

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https://infoscience.epfl.ch/record/297869?ln=en

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Gravitational-wave observatory

A gravitational-wave detector (used in a gravitational-wave observatory) is any device designed to measure tiny distortions of spacetime called gravitational waves. Since the 1960s, various kinds of

Gravitational wave

Gravitational waves are waves of the intensity of gravity that are generated by the accelerated masses of an orbital binary system, and propagate as waves outward from their source at the speed of li

Telescope

A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally it was an optical instrument using lenses, curved mirror