LIGO detector characterization in the second and third observing runs

D. Davis, California Institute of Technology
J. S. Areeda, California State University, Fullerton
B. K. Berger, Stanford University
R. Bruntz, Christopher Newport University
A. Effler, LIGO Livingston
R. C. Essick, The University of Chicago
R. P. Fisher, Christopher Newport University
P. Godwin, Pennsylvania State University
E. Goetz, The University of British Columbia
A. F. Helmling-Cornell, University of Oregon
B. Hughey, Embry-Riddle Aeronautical University, Prescott
E. Katsavounidis, LIGO, Massachusetts Institute of Technology
A. P. Lundgren, University of Portsmouth
D. M. Macleod, Cardiff University
Z. Márka, Columbia University
T. J. Massinger, LIGO, Massachusetts Institute of Technology
A. Matas, Max Planck Institute for Gravitational Physics (Albert Einstein Institute)
J. McIver, The University of British Columbia
G. Mo, LIGO, Massachusetts Institute of Technology
K. Mogushi, Missouri University of Science and Technology
P. Nguyen, University of Oregon
L. K. Nuttall, University of Portsmouth
R. M.S. Schofield, University of Oregon
D. H. Shoemaker, LIGO, Massachusetts Institute of Technology
S. Soni, Louisiana State University
A. L. Stuver, Villanova University
A. L. Urban, Louisiana State University
G. Valdes, Louisiana State University
M. Walker, Christopher Newport University
R. Abbott, California Institute of Technology
C. Adams, LIGO Livingston
R. X. Adhikari, California Institute of Technology
A. Ananyeva, California Institute of Technology


The characterization of the Advanced LIGO detectors in the second and third observing runs has increased the sensitivity of the instruments, allowing for a higher number of detectable gravitational-wave signals, and provided confirmation of all observed gravitational-wave events. In this work, we present the methods used to characterize the LIGO detectors and curate the publicly available datasets, including the LIGO strain data and data quality products. We describe the essential role of these datasets in LIGO–Virgo Collaboration analyses of gravitational-waves from both transient and persistent sources and include details on the provenance of these datasets in order to support analyses of LIGO data by the broader community. Finally, we explain anticipated changes in the role of detector characterization and current efforts to prepare for the high rate of gravitational-wave alerts and events in future observing runs.