Canuel B. auteur aut IRD Bertoldi A. auteur aut IRD Amand L. auteur aut IRD di Borgo E. P. auteur aut IRD Chantrait T. auteur aut IRD Danquigny C. auteur aut IRD Alvarez M. D. auteur aut IRD Fang B. auteur aut IRD Freise A. auteur aut IRD Geiger R. auteur aut IRD Gillot J. auteur aut IRD Henry S. auteur aut IRD Hinderer J. auteur aut IRD Holleville D. auteur aut IRD Junca J. auteur aut IRD Lefevre G. auteur aut IRD Merzougui M. auteur aut IRD Mielec N. auteur aut IRD Monfret Tony auteur aut IRD Pelisson S. auteur aut IRD Prevedelli M. auteur aut IRD Reynaud S. auteur aut IRD Riou I. auteur aut IRD Rogister Y. auteur aut IRD Rosat S. auteur aut IRD Cormier E. auteur aut IRD Landragin A. auteur aut IRD Chaibi W. auteur aut IRD Gaffet S. auteur aut IRD Bouyer P. auteur aut IRD text journalArticle eng text/pdf reformatted digital access We present the MIGA experiment, an underground long baseline atom interferometer to study gravity at large scale. The hybrid atom-laser antenna will use several atom interferometers simultaneously interrogated by the resonant mode of an optical cavity. The instrument will be a demonstrator for gravitational wave detection in a frequency band (100 mHz-1 Hz) not explored by classical ground and space-based observatories, and interesting for potential astrophysical sources. In the initial instrument configuration, standard atom interferometry techniques will be adopted, which will bring to a peak strain sensitivity of 2 center dot 10(-13)/root Hz at 2 Hz. This demonstrator will enable to study the techniques to push further the sensitivity for the future development of gravitational wave detectors based on large scale atom interferometers. The experiment will be realized at the underground facility of the Laboratoire Souterrain a Bas Bruit (LSBB) in Rustrel-France, an exceptional site located away from major anthropogenic disturbances and showing very low background noise. In the following, we present the measurement principle of an in-cavity atom interferometer, derive the method for Gravitational Wave signal extraction from the antenna and determine the expected strain sensitivity. We then detail the functioning of the different systems of the antenna and describe the properties of the installation site. specialized 066 020 8 art. 14064 [23 ] 2018 2045-2322 https://www.documentation.ird.fr/hor/fdi:010074031 10.1038/s41598-018-32165-z 2045-2322 [F B010074031] https://www.documentation.ird.fr/hor/fdi:010074031 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers18-09/010074031.pdf IRD - Base Horizon / Pleins textes 2018-10-03 2023-07-11 fdi:010074031 fre