Report
Visitors’ Voices
■It was an incredible opportunity to visit Japan, and I found the country very welcoming and fascinating to explore. Visiting the Tokyo Institute of Technology and the University of Tokyo and seeing the projects being worked on there was a great way to start the week. I was able to attend the KAGRA Face to Face Meeting and learn more about the KAGRA collaboration as a whole. Attending this was particularly productive, as there I discovered my research was particularly relevant to a new key project for KAGRA and was able to talk with the researcher leading the project. The highlight of my time in Japan however was visiting KAGRA and receiving a tour of the site. Seeing the interferometer in person and meeting the people working there was a unique experience.（U Adelaide/ Master student/ Visited Tokyo Tech, U Tokyo, and KAGRA, in Aug 2024)
■Our trip to Japan aimed to establish collaborations through the ASPIRE GW initiative. The visit included participating in an ASPIRE GW workshop, where we discussed potential partnerships and the future of the gravitational wave field, followed by an invitation to attend a three-day KAGRA face-to-face meeting. This provided valuable insight into the operation of the gravitational wave detector, and I had the opportunity to engage with researchers and students working across commissioning, data analysis, and theory. Following the workshop, we travelled to KAGRA for an in-depth tour of the detector, guided by key commissioners and researchers. They provided a detailed overview of the detector and its systems. Back in Australia, my work involves a suspension system originally designed for KAGRA, and I had the opportunity to have productive discussions on optimizing its performance and exploring further collaborative efforts. Overall, this trip was a great opportunity to establish international professional relationships. (UWA/ PhD student/ Visited Tokyo Tech, U Tokyo and KAGRA, in Aug 2024)
■I interacted with people in Australia who have common interests, especially related to Birefringence. In near future I am looking forward to collaborate with Dr. Carl Blair who is working on Birefringence related issues for LIGO by his research in Australia. We plan to arrange some form of meeting in future to have fruitful discussion related to our methodology. Other than people from Australian organization, I also interacted with people from USA to understand about Thermal compensation. （Tokyo Tech/ Master student/ Visited Hamilton Island: GWADW2024, in May 2024）
■I participated in GWADW and exchanged a lot of useful information. At the workshop, I presented a poster and a discussion session panel on my research on my milligram-scale optomechanical pendulum experiment. I was able to discuss my research with many people and learn the latest information about gravitational wave detectors from scientists in Australia and around the world. I can expect that my participation in this workshop will help me to accelerate my research and contribute to the field of gravitational waves in the future. (U Tokyo/ Researcher/ Visited Hamilton Island: GWADW2024, in May 2024)
■This business trip allowed me to present my research activities about birefringence compensation of crystalline substrates at GWADW in a poster and an oral presentation. I could also discuss with LIGO-Virgo-KAGRA colleagues on possible collaborative research. Especially on investigating sapphire impurities at several wavelengths, the possibility to investigate future Faraday Rotator material birefringence losses, as well as AlGaAs coating and Silicon beam-splitter birefringence and the possible implementation and noise coupling of the proposed birefringence compensation scheme. (NAOJ/ Researcher/ Visited Hamilton Island: GWADW2024, in May 2024)
■In this business trip, I joined in GWADW poster session, and visited ANU (Australian National University) and UWA (University of Western Australia). At each place, I exchanged the information about gravitational wave science, especially related to vibration isolation system (VIS). One of the specific results, I got some good contact with E-test researcher who has worked with VIS. E-test is the R&D group for Einstein Telescope (ET). The researcher said that I want to visit KAGRA to see VIS and talk with VIS member if there are opportunities. Between KAGRA and ET, there are common characteristics, for example employing cryogenic and passive VIS. So, this interaction might serve as a catalyst for active exchange activities among the VIS members of KAGRA and E-test. (U Tokyo/ PhD student/ Visited Hamilton Island: GWADW2024, ANU and UWA, in May 2024）
■GWADW was one of the best conferences I have attended recently. The conference style facilitated conversations with several researchers and allowed me to learn about research topics beyond my own. I had an in-depth conversation with a postdoc working on silicon suspension and received suggestions on evaluating issues with KAGRA’s suspension. After GWADW, I visited UWA (University of Western Australia) and ANU (Australian National University). At UWA, I discussed with Mr. Carl Blair the design of a low-loss support structure to evaluate the Q factor of a sapphire test mass. We also discussed the potential of employing fin-type heat exchangers similar to E-TEST to cool NEMO test masses and the timeline for installing cryogenic infrastructure at Gingin. The visit to ANU was exciting. The cryogenic experiments to directly measure the thermal noise of silicon cantilevers and coating thermal noise were quite intriguing and gave me ideas to explore at KAGRA. Additionally, I visited the new coating facility and hope to collaborate with them to test different coating recipes for KAGRA in the future. Overall, the trip was very beneficial. I also discussed with a few invited researchers the possibility of visiting my lab in Japan and participating in KAGRA F2F meetings. （NAOJ/ Researcher/ Visited Hamilton Island: GWADW2024, ANU and UWA, in May 2024）
■I attended GWADW held on Hamilton Island, Australia, where I presented a poster titled “Estimation of quantum noise in space gravitational-wave antenna DECIGO with optical-spring quantum locking considering mixture of vacuum fluctuations.” Throughout the workshop, I engaged in discussions with researchers from other countries regarding gravitational wave detection. Additionally, I visited UWA (University of Western Australia) and ANU (Australian National University) to learn about the advanced efforts in gravitational wave detection in Australia. Interacting with Australian gravitational wave researchers provided me with valuable insights and ideas for my future research, making the experience extremely beneficial. (Nagoya Univ/ Master student/ Visited Hamilton Island: GWADW2024, ANU and UWA, in May 2024）
■I attended GWADW held in Australia and gave one poster regarding the space-based gravitational wave detector, DECIGO. I was able to discuss things about my poster and others’ research. One productive thing to me is the problem of phase noise injection to squeezing measurements by Coherent Locking Field. I discussed this with one researcher in LIGO Livingston and found that there is a possibility that the non-linear interaction of the pump laser may cause phase noise.（U Tokyo/ PhD student/ Visited Hamilton Island: GWADW2024, in May 2024）
■During the GWADW, I gave a talk about birefringence characterizations for current KAGRA input test masses. I also gave a poster presentation showing my latest work on simulations of the influence of inhomogeneous birefringence to the sensitivity of gravitational wave detectors, and I won a Runner Up prize for my poster presentation. I met a lot of researchers from Europe, America and Asia, and discussed with them about the latest information and new ideas for gravitational wave detection, such as the future development for Finesse, the future study of birefringence for cryogenic detectors, the high-frequency detection, optical spring effect and so on. (U Tokyo/ Researcher/ Visited Hamilton Island: GWADW2024, in May 2024）