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Abstract Magnetar giant flares are rare and highly energetic phenomena observed in the transient sky whose emission mechanisms are still not fully understood. Depending on the nature of the excited modes of the magnetar, they are also expected to emit gravitational waves (GWs), which may bring unique information about the dynamics of the excitation. A few magnetar giant flares have been proposed to be associated with short gamma-ray bursts. In this paper we use a new gravitational-wave search algorithm to revisit the possible emission of GWs from four magnetar giant flares within 5 Mpc. While no gravitational-wave signals were observed, we discuss the future prospects of detecting signals with more sensitive gravitational-wave detectors. In particular, we show that galactic magnetar giant flares that emit at least 1% of their electromagnetic energy as GWs could be detected during the planned observing run of the LIGO and Virgo detectors at design sensitivity, with even better prospects for third-generation detectors.
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Seismic Cloaking for LIGO
We investigate the feasibility of using trees as a seismic meta-material that could shield the LIGO detectors from seismic activity. This seismic cloak would reflect low frequency surface waves away from the detector, thereby increasing the sensitivity of the detectors. This study models the energy transfer from surface waves as they pass through the bandgap filters designed from trees in different arrangements. The attenuation and rejection will hopefully serve to cloak the LIGO detectors from seismic activity. This work could have future impact on high sensitivity detectors, leading to more detections of merger events.
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- Award ID(s):
- 1757303
- PAR ID:
- 10089819
- Date Published:
- Journal Name:
- LIGO Laboratory Summer 2018 Undergraduate Research
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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