As the sensitivity and observing time of gravitational-wave (GW) detectors increase, a more diverse range of signals is expected to be observed from a variety of sources. GW signals with duration between 10-1000s could be emitted by a range of astrophysical sources: newly-born neutron stars, instabilities in accretion disk around black holes, magnetar flares... Because most of these processes are poorly modeled, detection must rely on generic search algorithms, which make few or no assumptions on the nature of the signal. However, the computational cost of those searches remains a limiting factor, which leads to suboptimal sensitivity. I present a new data analysis pipeline to search for unmodeled long-lived transient GW signals with duration between 10 and 1000 s, based on an excess cross-power statistic in a network of detectors. The pipeline is intended to reduce computational cost and increase detection sensitivity for a wide range of signal morphologies. It is used to perform a search for a GW counterpart around a sample of short GRBs that are associated to a magnetar giant flare origin.
Cosimo Nigro, César Jesús-Valls, Jan Ollé