We present the results of a search for short- and intermediate-duration gravitational-wave signals from four magnetar bursts in Advanced LIGO's second observing run. We find no evidence of a signal and set upper bounds on the root sum squared of the total dimensionless strain (h rss ) from incoming intermediate-duration gravitational waves ranging from 1.1 ×10 -22 at 150 Hz to 4.4 ×10 -22 at 1550 Hz at 50% detection efficiency. From the known distance to the magnetar SGR 1806-20 (8.7 kpc), we can place upper bounds on the isotropic gravitational-wave energy of 3.4 ×10 44 erg at 150 Hz assuming optimal orientation. This represents an improvement of about a factor of 10 in strain sensitivity from the previous search for such signals, conducted during initial LIGO's sixth science run. The short-duration search yielded upper limits of 2.1 ×10 44 erg for short white noise bursts, and 2.3 ×10 47 erg for 100 ms long ringdowns at 1500 Hz, both at 50% detection efficiency.
Publication Source (Journal or Book title)
Abbott, B., Abbott, R., Abbott, T., Abraham, S., Acernese, F., Ackley, K., Adams, C., Adhikari, R., Adya, V., Affeldt, C., Agathos, M., Agatsuma, K., Aggarwal, N., Aguiar, O., Aiello, L., Ain, A., Ajith, P., Allen, G., Allocca, A., Aloy, M., Altin, P., Amato, A., Ananyeva, A., Anderson, S., Anderson, W., Angelova, S., Antier, S., Appert, S., Arai, K., Araya, M., Areeda, J., Arène, M., & Arnaud, N. (2019). Search for Transient Gravitational-wave Signals Associated with Magnetar Bursts during Advanced LIGO's Second Observing Run. Astrophysical Journal, 874 (2) https://doi.org/10.3847/1538-4357/ab0e15