중력파 관측 10주년 기념 워크샵 -- Workshop for the 10th Anniversary of the Discovery of Gravitational Waves

27 Aug 2025, 09:30 → 28 Aug 2025, 18:00 Asia/Seoul

Seoul National University

Workshop for the 10th Anniversary of the Discovery of Gravitational Waves and KGWG Assembly Meeting

The 2025 Korean Gravitational Wave Group (KGWG) Summer Meeting will be held at Seoul National University during Aug. 27 (Wed) - 28 (Thu), 2025. 

This year is the 10th anniversary of the historic first observation of gravitational waves, GW150914. To celebrate it the meeting will focus on 

• Dedicated reviews on the main scientific achievements
• Impacts on various fields of science and technology
• Future prospects in gravitational wave research
• Strategic discussions on GW science in Korea

 in addition to the usual contributed talks by members. To mark the 10th anniversary a public lecture is also planned for students and citizens.

We encourage you to present your work or work in progress. There is no registration fee.

Important dates:

• Registration Re-opened: August 20 - 25 (Mon), 2025 11:59 KST
• Registration Deadline: August 1 (Tue), 2025 23:59 KST ==> August 7 (Thurs)
• Abstract Submission Deadline: August 1 (Tue), 2025 23:59 KST  ==> August 7 (Thurs)
  • Abstract submission requires a KGWG Indico account.
  • If you don't have an account yet, you can create it via the 'Login' button on the top-right corner.

We look forward to welcoming you at SNU for this occasion!

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Venue

Rm. 101 in Bld. 28 at Seoul National University

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Invited Speakers

• Zong-Hong Zhu (Beijing Normal University): "Building the Future of Gravitational Wave Astronomy and A Ground-Based Detector in China" 
• Sheng Yang (Henan Academy of Sciences): "Electromagnetic Signals from Gravitational Wave Events"
• Gopakumar Achamveedu (Tata Institute of Fundamental Research): "Nano-Hz Gravitational Wave Astronomy: Its implications and promises"
• Arman Shafieloo (KASI): "Cosmological Impact of Gravitational Wave Astronomy"
• Hyung-Mok Lee (Seoul National University): "Historical overview of the KGWG and its future"
• Hyung Won Lee (Inje University): "Summary on the GW events observed and their implications" 
• John J. Oh (National Institute for Mathematical Sciences): "KGWG efforts with Noises: from DetChar works to Next-Generation GW Sensors"
• June Gyu Park (Yonsei University): "Technical improvement with GW detector"
• Kyujin Kwak (UNIST): "Neutrino astronomy: a key-player in multi-messenger astronomy"
• Myungshin Im (Seoul National University): "Optical Follow-up Observations of Gravitational-wave Sources: Past, Present, and Future"
• Sungho Lee (KASI): "Technology Developments in Korea for GW Detectors"
• Yeong-Bok Bae (Chung-Aang U.): "Numerical Relativity in the Gravitational Wave Era"
• Youngmin Kim (KASI): "GW impact on nuclear physics"

 

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Program at a glance

• Download timetable [Link]

 

• Day 1 (Aug. 27, Wed.)
  • 10:00--12:30 Session I  (Chair: Gungwon Kang)
    • 10:00-10:10 Hyung Won Lee (President of KGWG): Welcoming address
    • 10:10-10:40 Hyung Won Lee (Inje University): "Summary on the GW events observed and their implications"
    • 10:40-11:10 Zong-Hong Zhu (Beijing Normal University): "Building the Future of Gravitational Wave Astronomy and A Ground-Based Detector in China“ 
    • 11:10-11:40 Sheng Yang (Henan Academy of Sciences): "Electromagnetic Signals from Gravitational Wave Events"
    • 11:40-12:10 Gopakumar Achamveedu (Tata Institute of Fundamental Research, On-line presentation): "Nano-Hz Gravitational Wave Astronomy: Its implications and promises"
    • 12:10-12:30 Discussions in all
       
  • 12:30--14:00 Lunch
  • 14:00--15:30 Session II (Chair: Kyungmin Kim)
    • 14:00-14:30 Hyung-Mok Lee (Seoul National University): “Historical overview of the KGWG and its future“
    • 14:30-15:00 Sungho Lee (KASI): “Technology Developments in Korea for GW Detectors”
    • 15:00-15:30 John J. Oh (NIMS): "KGWG Efforts with Noises: from Detchar Works to Next-Generation GW Sensors"
       
  • 15:30-15:50 Coffee Break
  • 15:50-16:00 Photo Session 
  • 16:00--18:00 KGWG General Assembly (Chair: Edwin J. Son)
    • 16:00-16:30 Awards, Approval of amended articles, New members, News from members and other business
    • 16:30-17:40 Issues
      • New Division of GW at KAS
      • Reorganization of LIGO, Virgo & KAGRA: IGWN
        • Hyung Won Lee (Inje University): Introduction to IGWN
        • Gungwon Kang (CAU): Discussions on Korean membership to IGWN
    • 17:40-18:00 Discussions in all
       
  • 18:30--20:30 Dinner

 

• Day 2 (Aug. 28, Thu.)
  • 09:00--10:40 Session III (Chair: Nicolas Chartier)
    • 9:00-9:30 Youngmin Kim (KASI): "GW impact on nuclear physics"
    • 9:30-10:00 Arman Shafieloo (KASI): “Cosmological Impact of Gravitational Wave Astronomy"
    • 10:00-10:30 Yeong-Bok Bae (Chung-Aang U.): "Numerical Relativity in the Gravitational Wave Era"
    • 10:30-10:40 Discussions in all
       
  • 10:40-11:00 Coffee Break
     
  • 11:00--12:30 Session IV (Chair: Ji Hoon Kim)
    • 11:00-11:30 Myungshin Im (SNU): "Optical Follow-up Observations of Gravitational-wave Sources: Past, Present, and Future"
    • 11:30-12:00 June Gyu Park (Yonsei University): "Technical improvement with GW detector“
    • 12:00-12:30 Kyujin Kwak (UNIST): "Neutrino astronomy: a key-player in multi-messenger astronomy"
       
  • 12:30--14:00 Lunch 
  • 14:00--15:40 Session V (Chair: Kyung-ha Lee)
    • 14:00-14:15 Hojae Ahn (Kyung Hee University): Development of a tip-tilt mirror and a deformable mirror for active mode-matching experiment
    • 14:15-14:30 Sumin Lee (Yonsei University): Einstein-Podolsky-Rosen quantum entanglement squeezing for future gravitational-wave detectors
    • 14:30-14:45 Chan Park (Henan Academy of Sciences): Source Positioning for Multi-Channel Gravitational Wave Data
    • 14:45-15:00 KELLIE LOUISE ONEAL AULT (Sogang University): Enhancing Constraints on First-Order Phase Transitions in the Early Universe Through Multi-Source Gravitational-Wave Background Analysis
    • 15:00-15:15 GwangEon Seong (Ewha Womans University): Exploring New MeV Neutrino Sources with a Next-generation WbLS Detector
    • 15:15-15:30 Mu-In Park (Sogang University): Testing New Rotating Black Holes in a Viable Lorentz-Violating Gravity
    • 15:30-15:40 Discussions in all
       
  • 15:40--16:00 Coffee Break
     
  • 16:00--17:00 Session VI (Chair: Hyung-Mok Lee)
    • 16:00-16:10 Minhyo Kim (Sungkyunkwan University): "Voices from young members of KGWG"
    • 16:10-16:20 Gungwon Kang (CAU): "Statistics on KGWG"
    • Perspectives and where to go
    • Discussions on Strategic Planning
       
  • 17:00--17:10 Hyung-Mok Lee (LOC Chair): Closing remark
     

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Organizing Committee

• Program Committee
  • Gungwon Kang (Chung-Ang U., Chair)
  • June Gyu Park (Yonsei U.)
  • Sungho Lee (KASI)
  • Kyujin Kwak (UNIST)
  • Young-Min Kim (KASI)
  • 
     
• Local Organizing Committee
  • Hyung-Mok Lee (SNU, Chair) 
  • Myungshin Im (SNU)
  • Elahe Khalouei (SNU)
  • Nicolas Chartier (SNU)
  • Joohee Lee (이주희, SNU)

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Contact

Joohee Lee (이주희): happyjoo2 [AT] snu.ac.kr/ 02-880-4213, or Hyung-Mok Lee (LOC Chair): hmlee [AT] snu.ac.kr

Wednesday, 27 August

Business Sesion: Welcome Address

Convener: Prof. Hyung Won Lee (Inje University)

Research Session: Session I

1 Summary on the GW events observed and their implications

Summary of GW detections and their implications and future

Speaker: Prof. Hyung Won Lee (Inje University)

KGWG2025_summer_v3.pdf

2 Building the Future of Gravitational Wave Astronomy and A Ground-Based Detector in China

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Speaker: Prof. Zong-Hong Zhu (Beijing Normal University)

3 Electromagnetic Signals from Gravitational Wave Events

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Speaker: Prof. Sheng Yang (Henan Academy of Sciences)

4 Nano-Hz Gravitational Wave Astronomy: Its implications and promises

Maturing Pulsar Timing Arrays (PTAs) are expected to usher in the era of nano-Hertz gravitational wave (GW) astronomy, with the International Pulsar Timing Array (IPTA) playing a central role in this global effort. The astrophysical and cosmological implications of the ongoing IPTA efforts will be explored and these efforts are anticipated to lay the foundation for persistent multi-messenger GW astronomy, particularly targeting individual supermassive black hole binaries/candidates, and their significance will be further amplified in the Square Kilometre Array (SKA) era.
Importantly, the coming decade is expected to witness the emergence of multi-band GW astronomy, and a growing Asian collaboration across the GW landscape would strengthen regional capabilities and contribute substantially to the global GW efforts.

Speaker: Prof. Gopakumar Achamveedu (Tata Institute of Fundamental Research)

Gopu_MM_nHz_GWA_Brief.pptx

5 Discussion in all

Lunch

Review Session: Session II

Convener: Kyungmin Kim (Korea Astronomy and Space Science Institute)

6 Historical overview of the KGWG and its future

KGWG was established in 2003 as a voluntary group of about 10 people and it has expanded to include about 100 people. KGWG became member of LIGO Scientific Collaboration in 2010 and subsequently expanded to participate other collaborations such as KAGRA and ET. In this talk, I will go through the venture of the Korean gravitational wave community. Then I will make some suggestions on the future direction of gravitational-wave research in Korea.

Speaker: Hyung Mok Lee (Seoul National University)

hmlee.pdf

7 Technology Developments in Korea for GW Detectors

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Speaker: Sungho Lee (Korea Astronomy and Space Science Institute (KASI))

GW tech in Korea_20250827.pdf

8 The Chronicles of the KGWG-Detchar

KGWG efforts with Noises: from Detchar works to Next-Generation GW Sensors:

This presentation outlines the research activities and achievements of the Korean Gravitational-Wave Group (KGWG) in tackling noise-related challenges across multiple domains. KGWG has conducted extensive studies on detector characterization, noise mitigation techniques, and the application of machine learning to identify and suppress noise artifacts in gravitational-wave data. These efforts have naturally evolved into an interest in developing superconducting gravity sensor, particularly as research on environmental noise led to broader inquiries into geophysical phenomena.

Motivated by this shift, KGWG has been expanding its scope by identifying and promoting science cases that can be addressed through superconducting gravity sensors. These efforts are materializing in initiatives such as the YeMiGO underground micro-gravity observatory and the East-Asian superconducting gravimeter network ENIGMA. Recently, we also have begun R&D on a superconducting gravity gradiometer as a foundational technology for SOGRO-type instruments as a future GW detector.

The current research focus lies in linking environmental noise studies—such as Newtonian noise, seismic coupling, and magnetic disturbances—with the development of sensors capable of canceling or bypassing these noise sources. Furthermore, KGWG is exploring the convergence of gravitational and geophysical instrumentation, and pursuing a multi-band, multi-messenger strategy in collaboration with East Asian partners.

In this talk, we present an overview of past and ongoing research directions, and discuss the future vision for advancing next-generation gravitational sensing in Korea.

Speaker: John J. Oh (NIMS)

KGWGGA2025_10Anniversary_20250827.pdf

Break

Photo Session

Business Sesion: KGWG General Assembly

Convener: Dr Edwin J. Son (National Institute for Mathematical Sciences)

9 Approval of amended articles, Awards, New members and other business

Speaker: Dr Edwin J. Son (National Institute for Mathematical Sciences)

10 New Division of GW at KAS

Speaker: Dr Edwin J. Son (National Institute for Mathematical Sciences)

11 Introduction to IGWN

Introduce IGWN anew organization

Speaker: Prof. Hyung Won Lee (Inje University)

12 Discussions on Korean membership to IGWN

There has been a series of discussions about how Korean GW community, including LIGO & KAGRA, should do for memberships and groupings in the coming new governance of IGWN. Here output of such discussions and some suggestions will be reported to open discussions among KGWG members.

Speaker: Prof. Gungwon Kang (Chung-Ang University)

gwkang_IGWN.pptx

13 Discussion in all

Speaker: Dr Edwin J. Son (National Institute for Mathematical Sciences)

Dinner

Thursday, 28 August

Review Session: Session III

14 GW impact on nuclear physics

I will explain the impact of observations of neutron stars detected through gravitational waves on nuclear physics.

Speaker: Young-Min Kim (Korea Astronomy and Space Science Institute (KASI))

20250828-kgwg-ymkim.pdf

15 Cosmological Impact of Gravitational Wave Astronomy

Gravitational wave astronomy has opened a new window for cosmology, providing independent probes of the universe’s expansion and structure. Standard sirens enable direct measurements of the Hubble constant and tests of dark energy, while future detections of the stochastic background will help revealing physics of the early universe. This talk highlights the current progress and future prospects of gravitational wave cosmology in constraining the physics of the late universe.

Speaker: Arman Shafieloo (KASI/UST)

16 Numerical Relativity in the Gravitational Wave Era

Numerical relativity has been essential in establishing gravitational-wave astronomy, from validating the first black hole merger detection to probing the dense matter in neutron stars. It has provided accurate models of strong-field dynamics and multi-messenger signals, transforming our understanding of compact objects. In this talk, I will review its historical milestones and illustrate its key applications in astrophysics.

Speaker: Dr Yeong-Bok Bae (Chung-Ang University)

YBBae.pdf

17 Discussion in all

Break

Review Session: Session IV

18 Technical improvement with GWdetector

This is dummy submission.

I'll update it soon

Speaker: June Gyu Park (Yonsei University)

10thani_jpark.pdf

19 Optical Follow-up Observations of Gravitational-wave Sources: Past, Present, and Future

Multimessenger observation of gravitational-wave (GW) sources can teach us much more than GW observation alone. Through optical identification of GW events, one can localize the event to sub-arcsecond accuracy, which allows us to identify the GW event host galaxy and its redshift for various astrophysical applications. Through the time evolution study of the EM counterpart, one can learn astrophysical processes of kilonovae, which are known to produce the bulk of heavy elements such as gold. In this talk, we will review the past and present efforts of optical counterpart observations of GW events. We will describe current challenges and future efforts that might overcome the difficulties today. We will give emphasis on our current efforts of multimessenger observations in Korea, the GW EM-Counterpart Korean Observatory (GECKO), and two key GECKO facilities, the 7-Dimensional Telescope and KMTNet.

Speaker: Myungshin Im (Seoul National University)

MMA_Im.pptx

20 Neutrino astronomy: a key-player in multi-messenger astronomy

Multi-messenger astronomy generally includes both electromagnetic (EM) wave and all of non-EM astrophysical signals such as gravitational wave (GW), neutrino, and atomic nuclei often called cosmic ray. Among these, GW has been leading the multi-messenger astronomy since its first detection in 2015. GW impacts the astronomy community significantly because the number of observation data is large enough to raise up new questions, for example, formation of binary stellar mass black holes and intermediate mass black holes. In contrast, neutrino astronomy still seems out of attention of the astronomy community. In this talk, I review a brief history of neutrino astronomy discussing its current limitation. I also discuss briefly the potential of neutrino astronomy as a key-player in multi-messenger astronomy.

Speaker: Kyujin Kwak (UNIST)

Kwak-NeutrinoAstronomy-20250828.pdf

Lunch

Research Session: Session V

21 Development of a tip-tilt mirror and a deformable mirror for active mode-matching experiment

Mode mismatch is one of the major factors that limits the sensitivity of gravitational wave detectors (GWDs), and it is expected to be an even more critical issue for next generation GWDs. Active mode-matching technique, which compensates for time-varying relative motion between suspended cavities and thermal effect on mirrors due to high power lasers, can be adopted to mitigate the mode mismatch. KHU, YU, and KASI are collaborating on an experiment to implement basic active mode-matching in the KASI squeezing lab. For this experiment, KHU has developed two types of active modules: a tip-tilt mirror and a deformable mirror with a single actuator. In this talk, we will introduce our modules with their performance test results at the component level.

Speaker: Hojae Ahn (KHU)

22 Einstein-Podolsky-Rosen quantum entanglement squeezing for future gravitational-wave detectors

Frequency-independent squeezing (FIS) has been employed to mitigate quantum noise (QN) in gravitational wave detectors (GWDs). However, this technique only suppresses shot noise and cannot mitigate disturbances across the entire detection band (10 Hz to 10 kHz).To achieve broadband QN reduction, current detectors use frequency-dependent squeezing (FDS), implemented by reflecting the FIS beam from a ~300 m detuned filter cavity (FC). Such systems, however, demand substantial infrastructure, posing significant challenges for the Einstein Telescope (ET). A promising alternative approach for broadband QN reduction, which avoids the need for external FCs, is based on Einstein-Podolsky-Rosen (EPR) quantum entanglement.
To explore this, we are developing an experimental setup in the Virgo R&D squeezing laboratories to assess the performance of EPR-based FDS in the audio-frequency range relevant to GWDs. This project is part of an international collaboration involving 20 researchers from INFN (Italian National Institute of Nuclear Physics) branches and related Italian universities (Rome, Naples, Perugia, Genoa), along with Korean institutions including the Korea Astronomy and Space Science Institute (KASI), Kyung Hee University, and Yonsei University. This presentation will report on the current status of the EPR experiment and highlight the contributions of Korean researchers in next-generation technologies for GWD.

Speaker: Mr Sumin Lee (Yonsei University)

ET-0401A-25_Einstein-Podolsky-Rosen quantum entanglement squeezing for future gravitational-wave detectors_Final.pdf

23 Source Positioning for Multi-Channel Gravitational Wave Data

The conventional method for localizing the sky position of a gravitational wave (GW) source relies on triangulation using the phase differences between pairs of multiple detectors. However, when the detectors are located close together compared to the wavelength of the GWs, or when a tensorial detector is small relative to the GW wavelength, this method becomes ineffective due to insufficient phase differences. We propose a novel approach that determines the source direction based on the tensor components of the GW signal instead of the phase differences, which is applicable to configurations with multiple nearby detectors or tensorial detectors.

Speaker: Dr Chan Park (Henan Academy of Sciences)

[2025.08.27] Source Positioning for Multi-Channel Gravitational Wave Data.pdf

24 Enhancing Constraints on First-Order Phase Transitions in the Early Universe Through Multi-Source Gravitational-Wave Background Analysis

First-order phase transitions (FOPTs) in the early Universe can generate a stochastic gravitational-wave background, potentially detectable by observatories such as LIGO, Virgo, and KAGRA. In our analysis, we account for all relevant astrophysical sources contributing signals within the LVK frequency band, aiming to enhance the sensitivity of constraints on the FOPTs model considered.

Speaker: Dr KELLIE LOUISE ONEAL AULT (Sogang University)

ONEAL_AULT_KGWG_AUG2025.pdf

25 Exploring New MeV Neutrino Sources with a Next-generation WbLS Detector

Neutrino astronomy offers a unique opportunity to explore regions that cannot be probed by electromagnetic observations, such as the cores of stars. To date, the Sun and SN 1987A have been observed through MeV neutrinos only, but next-generation detectors make it possible to observe a broader range of astrophysical sources. In this study, we introduce a water-based liquid scintillator (WbLS) detector as a platform that can identify new MeV neutrino sources. We investigate whether new targets such as red supergiants, presupernova stars, and the Sun via its CNO cycle can produce signals strong enough to be observed. Using stellar evolution models and WbLS detector concepts, we assess the detectability of these sources and discuss what new insights such observations could offer.

Speaker: GwangEon Seong (Ewha Womans University)

Seong-KGWG-0828.pptx

26 Testing New Rotating Black Holes in a Viable Lorentz-Violating Gravity

We will discuss several new features in the recently discovered exact solution for rotating black holes in a viable Lorentz-violating gravity and its observational consequences.

Speaker: Mu-In Park (Sogang U.)

Rotating Black Holes in a Viable Lorentz-Violating Gravity - 복사본_08_28_SNU.pdf

27 Discussions

Break

Business Sesion

Convener: Hyung Mok Lee (Seoul National University)

28 Voices from young members of KGWG

I will organize and speak the opinions and suggestions on behalf of the young members of KGWG.

Speaker: Minhyo Kim (Sungkyunkwan University (SKKU))

29 Statistics on KGWG

Various statistics on the Korean Gravitational Wave Group (KGWG) including members, institutional affiliations, distributions and fields of research have been summarized. This information might be helpful for understanding GW research in Korea and planning its future.

Speaker: Prof. Gungwon Kang (Chung-Ang University)

gwkang_Statistics on KGWG.pptx

30 Perspectives and Strategic Planning

Perspectives and where to go
Discussions on Strategic Planning

Speaker: Prof. Gungwon Kang (Chung-Ang University)

Business Sesion: Closing Remark

Convener: Hyung Mok Lee (Seoul National University)