|
Size: 3900
Comment:
|
Size: 3783
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 16: | Line 16: |
| === The 129th REM: Mar. 4th, 2025 === | === The 132nd REM: Jun. 5th, 2025 === |
| Line 19: | Line 19: |
| * Time: 14:00-15:00 * Speaker: Yusuke Okuma (JAXA ISAS/UTokyo) * Title: ''"Development of Back-Linked Fabry-Perot Interferometer for Space Gravitational Wave Telescopes"'' |
* Time: 15:00-16:00 * Speaker: Alvin Li (U Tokyo, RESCEU) * Title: ''"Gravitational Wave Lensing: Current Status and Future Prospects"'' |
| Line 24: | Line 24: |
| Currently, space-based gravitational wave telescopes are being planned to observe low-frequency gravitational waves. Among them, DECIGO and B-DECIGO, which aim to observe gravitational waves in the 0.1 Hz band, propose a method using Fabry-Pérot cavities. One of the topologies for space-based gravitational wave detectors using cavities is the Back-Linked Fabry-Perot Interferometer (BLFPI). A BLFPI equips two lasers for each space craft and controls the frequencies of six lasers to satisfy six resonance conditions. This eliminates the need for precise control of the spacecraft's orbit. However, since the gravitational wave signal is obtained by interfering two independent lasers, the signal is contaminated by laser frequency noise. In a BLFPI, post-processing is performed using the beat signal and the error signal used for frequency control. Through post-processing, laser frequency noise is reduced, and gravitational wave signals distorted by finite control accuracy are restored. In this study, we constructed a BLFPI setup in the laboratory and conducted experiments to demonstrate the ability to recover gravitational wave signals through post-processing. To achieve this, a method was used to inject simulated gravitational wave signals into the experimental setup using an auxiliary laser. The simulated-gravitational wave signals were then injected into the system, and post-processing was applied to test whether the injected signals could be recovered. |
Gravitational lensing of gravitational waves offers a unique opportunity to probe both astrophysical and cosmological phenomena, from the population properties of compact binaries to the distribution of matter in the Universe. As gravitational waves travel through the Universe, their paths can be deflected, and their amplitudes can be (de)-magnified by intervening massive structures. This leads to various observable signatures, including magnification bias, arrival time delays, and repeated signals. In this talk, I will present an overview of gravitational wave lensing, beginning with the theoretical foundations and the classification of lensing regimes relevant to ground-based detectors. I will review the status of current searches for lensed gravitational wave events, highlighting recent results from the third observing run (O3) of the LIGO-Virgo-KAGRA collaboration. In addition, I will discuss the various methods employed in lensing analyses and the challenges associated with confidently identifying lensed events. I will then outline the prospects for detecting gravitational wave lensing in upcoming observing runs and the potential scientific returns such detections could offer. I will also discuss the specific contributions KAGRA can make in making the first lensed gravitational wave detection. |
| Line 38: | Line 37: |
| <<Include(gw_talks/archive_121_130)>> | <<Include(gw_talks/archive_131_140)>> |
| Line 46: | Line 45: |
| . {i} [[gw_talks/archive_121_130|121-130th GW-REM talks (2024-)]] | . {i} [[gw_talks/archive_131_140|131-140th GW-REM talks (2025-)]] . {i} [[gw_talks/archive_121_130|121-130th GW-REM talks (2024-2025)]] |
重力波研究交流会
GW research exchange meeting
Upcoming GW-REMs
The 132nd REM: Jun. 5th, 2025
- Time: 15:00-16:00
- Speaker: Alvin Li (U Tokyo, RESCEU)
Title: "Gravitational Wave Lensing: Current Status and Future Prospects"
- Abstract:
Gravitational lensing of gravitational waves offers a unique opportunity to probe both astrophysical and cosmological phenomena, from the population properties of compact binaries to the distribution of matter in the Universe. As gravitational waves travel through the Universe, their paths can be deflected, and their amplitudes can be (de)-magnified by intervening massive structures. This leads to various observable signatures, including magnification bias, arrival time delays, and repeated signals. In this talk, I will present an overview of gravitational wave lensing, beginning with the theoretical foundations and the classification of lensing regimes relevant to ground-based detectors. I will review the status of current searches for lensed gravitational wave events, highlighting recent results from the third observing run (O3) of the LIGO-Virgo-KAGRA collaboration. In addition, I will discuss the various methods employed in lensing analyses and the challenges associated with confidently identifying lensed events. I will then outline the prospects for detecting gravitational wave lensing in upcoming observing runs and the potential scientific returns such detections could offer. I will also discuss the specific contributions KAGRA can make in making the first lensed gravitational wave detection.
- Abstract:
The past GW REM talks
The 131-140th REM talks
The 131st REM: May. 19th, 2025
- Time: 15:00-16:00
- Speaker: Naoki Aritomi (U Tokyo)
Title: "Advanced LIGO detector performance in the fourth observing run"
- Abstract:
I will talk about the LIGO detector performance in O4 based on the recently published paper, Phys. Rev. D 111, 062002 (2025).
- Abstract:
Archives for the past talks
- Most of the archives for the earlier years are written in Japanese (it is a history!).
Useful links
How to receive the announcements
![/!\](/moin_static193/modern/img/alert.png "/!\")
One has to subscribe to the mailing list called gw_comm in order to receive our announcement emails. Please ask one of our organizers for subscription. The organizers can be found in this page.