Speaker
Dr
Keiko Kokeyama
(ICRR, University of Tokyo)
Description
The underground gravitational-wave detector, KAGRA, is rapidly being commissioned and integrated towards the joint observation run with LIGO and VIRGO.
The laser-interferometer type of the gravitational-wave detectors are based on very complicated optical systems, with numerous feedback control loops at an extreme high precision. Since the interferometer is so complex, there are many possible states of the operation, with different levels of noise contributions. Furthermore, the interferometer is affected by the environmental perturbations such as earthquakes and tidal waves of the ocean, through various noise coupling mechanisms.
The goal of the detector characterization (DetChar) is to understand the behavior of the interferometer, states of the environment, and various noise coupling mechanisms to the gravitational-wave channel. The study includes the software developments as well as instrumental experiments. The obtained insights of the interferometer are crucial both from the following three aspects:
(i) Data analysis. For when the gravitational-wave channel is analyzed for the event search, Detchar provides the state information of the interferometer which are based on the study of the interferometer behavior. The gravitational-wave channel data is avoided when the bad state so that the efficient searches can be performed and so to avoid false alerts of the gravitational-wave events.
(ii) Instruments. By studying the noise sources and their coupling routes, some of them are identified. When possible, those noises will be mitigated and the interferometer performance will be improved.
(iii) Commissioners. DetChar provides software tools also to present the status of the interferometer and environmental information. With such tools, specific plots of the instruments and DetChar results are easily accessible for the commissioners (and anyone in the collaboration) so the noise hunting will be done quicker and more efficiently.
Thus, detector characterization will serve as a "brigade" between the instruments and data analysis studies. In this talk, the status of the KAGRA detector characterization towards O3, and the prospects will be presented.
Primary author
Dr
Keiko Kokeyama
(ICRR, University of Tokyo)
Co-author
Dr
Takaaki Yokozawa
(Institute for Cosmic Ray Research, University of Tokyo)
