2024 KGWG Summer Meeting

22 Jul 2024, 09:30 → 23 Jul 2024, 17:50 Asia/Seoul

Auditorium, 1F Eunhasoo hall (KASI, Daejeon)

2024 KGWG Summer Meeting

The 2024 Korean Gravitational Wave Group (KGWG) Summer Meeting will be held from July 22 (Mon), 2024 to July 23 (Tue), 2024 at the Korea Astronomy and Space Science (KASI) Headquarters, Daejeon. 

By virtue of about a hundred gravitational-wave (GW) observations made thus far, the GW astronomy era has emerged and the GW science is one of active research fields in both astronomical and astrophysical communities. Consequently, the international GW science community is growing rapidly. Moreover, the next generation GW detectors will be online in the near future along with the initiation of the International Gravitational-Wave Observatory Network beyond the current LIGO-Virgo-KAGRA network. Therefore, it is timely to exchange our knowledge about what we have done and what we can do in the era of the GW astronomy and multi-messenger astronomy. 

During this Summer Meeting, we will discuss various topics in all disciplines of the GW science, such as 

• GW astrophysics (theoretical/observational)
• GW cosmology (theoretical/observational)
• GW data analysis 
• GW experiment 

We encourage you to submit an abstract of your original work corresponding to any discipline of the GW science. Please note that there is no restriction on the level of accomplishment, namely, you can submit an abstract of either a work already published at a scientific journal or an ongoing work.

We gently ask you to save the date of this meeting and following deadlines:

• Registration Deadline: July 1 (Mon), 2024 23:59 KST
• Abstract Submission Deadline: June 24 (Mon), 2024 23:59 KST
• (Extended) Abstract Submission Deadline: July 1 (Mon), 2024 23:59 KST
  • 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 seeing many of you at KASI this summer!

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Venue

Auditorium, 1F Eunhasoo hall, KASI, Daejeon (Please refer to 'Venue Map' to plan your own route.)

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Invited Speakers

(*: remote presentation)

• Hyung Won Lee (Inje University, Korea): "LVK operations for O4 and future"
• Arman Shafieloo (Korea Astronomy and Space Science Institute, Korea): "Reconstructing dark energy"
• Kanghoon Lee (Asia-Pacific Center for Theoretical Physics, Korea): "The Schwarzschild black hole from perturbation theory to all orders"
• Chunglee Kim (Ewha Womans University, Korea): "Multi-band GW astronomy"
• Chan Park* (Henan Academy of Sciences, China): "Gravitational-wave background and pulsar timing array"
• Myungshin Im (Seoul National University, Korea): "Current Status of 7-Dimensional Telescope and Search for Optical Counterparts of GW events"
• Francesco De Marco (Sapienza University, Italy): "Frequency-Dependent Squeezing in Virgo and future developments with EPR strategy"
• Sibilla Di Pace (Sapienza University, Italy): "Advanced Virgo detector, status and upgrades for the future observing runs"
• Marica Branchesi* (Gran Sasso Science Institute, Italy): "Prospects for multi-messenger perspectives with current and next generation observatories"
• Jan Harms* (Gran Sasso Science Institute, Italy): "The Newtonian-noise cancellation system at the Virgo detector"

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Program at a glance

• Day 1 (July 22, Mon)
  • 09:30--10:00 Registration & Welcoming address
  • 10:00--11:00 Invited Talks (Session I, Chair: Kyungmin Kim (KASI))
  • 11:10--12:30 Contributed Talks (Session II, Chair: Arman Shafieloo (KASI))
  • 12:30--14:00 Lunch
  • 14:00--15:50 Invited/Contributed Talks (Session III, Chair: Chang-Hwan Lee (Pusan Nat'l U.))
  • 16:00--17:30 KGWG General Assembly
    • Approval of amended article
    • Updates (IGWN, KAGRA, LIGO)
  • 18:30--20:30 Dinner
• Day 2 (July 23, Tue)
  • 09:00--10:40 Invited/Contributed Talks (Session IV, Chair: John J. Oh (NIMS))
  • 11:00--12:30 Invited/Contributed Talks (Session V, Chair: Sungho Lee (KASI))
  • 12:30--14:00 Lunch
  • 14:00--15:10 Invited/Contributed Talks (Session VI, Chair: June Kyu Park (Yonsei U.))
  • 15:30--17:00 Invited Talks (Session VII, Chair: Hyung Mok Lee (Seoul Nat'l U.))
  • 17:00--17:10 Closing remark
     

(The schedule in detail is available at 'Timetable' and 'Contribution List'.)

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Supports

We will provide

• Monday lunch 
• Monday dinner
• Tuesday lunch
   

to participants who have checked their attendance for each meal in the registration form.

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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)
  • Kyungmin Kim (KASI)
     
• Local Organizing Committee
  • Kyungmin Kim (KASI, Chair)
  • Chang Hee Kim (KASI)
  • Young-Min Kim (KASI)
  • Sungho Lee (KASI)
  • Byeongjun Park (KASI)
  • Yejin Kim (KASI)
  • Jeongcho Kim (NIMS)

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Contact

Kyungmin Kim (LOC Chair): kkim [AT] kasi.re.kr

Monday, 22 July

09:30 → 10:00 Registration & Welcoming

10:00 → 11:00 Session I (10:00--11:00, Monday)

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

10:00 [Session I] LVK Operations for O4 and future

The first period of the O4 observing run, O4a, started at 15:00 UTC 24 May 2023, and ended at 16:00 UTC 16 January 2024 for a period of commissioning between O4a and O4b.

The two LIGO detectors are now running with a sensitivity of 155-175 Mpc, and with duty cycles in recent days of 80-98%. There will be further minor adjustments to optimize the performance during the O4b observing period.

The Virgo detector is running with a sensitivity of 55-60 Mpc and is targeting a duty cycle of at least 80% for O4b. There will be further limited adjustments during the run, to improve its performance. At the moment, Virgo is reconsidering its plans for O5 and both the date on which we will be able to enter O5 and the target sensitivity are currently unclear. We expect to be able to define our plans for O5 in the second half of 2024.

On January 1st, 2024, a 7.6 magnitude earthquake struck near the KAGRA site, marking the most significant seismic tremor in the area of the KAGRA site in the past century. Among the nine mirror suspensions, three IMC mirror suspensions were recovered, and the IMC performance check is ongoing. We hope to finish other recovery works as soon as possible and restart commissioning, then join O4b before the end of O4 with a BNS range of around 10 Mpc.

Here I will summerize O4 summary and status.

Speaker: Prof. Hyung Won Lee (Inje University)

2024KGWG_Summer_Meeting.pdf

10:30 [Session I] Reconstructing Dark Energy

Reconstructing the expansion history of the universe and properties of dark energy have been among of the main goals of physical cosmology. I will discuss about reconstructing dark energy in light of most recent cosmological observations including DESI-2024 BAO observations, Union3 supernova compilation and Planck CMB data.

Speaker: Arman Shafieloo (KASI/UST)

22_July_2024_2024_KGWG.pdf

11:00 → 11:10 Coffee Break

11:10 → 12:30 Session II (11:10--12:30, Monday)

Convener: Arman Shafieloo (KASI/UST)

11:10 [Session II] Analysis of LIGO gravitational wave data using AI

Gravitational wave has been observed since LIGO first detected. Also, gravitational wave noise classification became needed. There have been many methods to classify them. We tried PCA preprocessing method on t-SNE algorithm to increase its performance.

Speaker: Woojin Lee (UNIST)

KGWG presentation(Woojin Lee).pptx

11:30 [Session II] Current research activities on future coating material and LIGO fellowship

Coating thermal noise (CTN) is identified as one of the limitations on the sensitivity of advanced LIGO (aLIGO) within its most sensitive frequency range. To enhance sensitivity, it is essential to replace the high reflective index material in the high reflective mirror coating of the test mass in gravitational wave (GW) detectors with a new material that has lower mechanical loss properties.
To efficiently identify new candidate materials, our study focuses on atomic structure characterization to understand the correlation between mechanical loss and the local atomic structure of amorphous metal oxide materials. In order to achieve this goal, our group applied electron pair distribution function (ePDF) analysis for short-range order (SRO) and fluctuation electron microscope (FEM) analysis for medium-range order (MRO) using diffraction data acquired from a transmission electron microscope (TEM).
In this talk, a recent update on the atomic structure study on potential coating materials done by the SKKU group will be presented. In addition, an introduction to on-site research activities done as LIGO fellows in the Hanford observatory during O4b will be included.

Speaker: Minhyo Kim (Sungkyunkwan University (SKKU))

KGWG SKKU report.pptx

11:50 [Session II] Spectral Lines for a Gravitational Wave

Spectral lines for a star light are the result of electromagnetic interaction between a single photon and a quantum system such as atoms or molecules. Observations of such absorption or emission lines can be used to extract various astrophysical information for the chemical elements of stars or interstellar medium. Similarly, we have considered the possibility of spectral lines for a gravitational wave through gravitational interaction between gravitons and gravitational quantum systems.

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

GW spectral lines.pptx

12:10 [Session II] Autoregressive search from unmodeled gravitational waves

Gravitational wave (GW) signals are inherently weak, making effective denoising techniques crucial in the presence of detector and environmental noise. In this talk, we introduce our recently published work (Kim et al. 2024), which presents a methodology for denoising gravitational wave data using an autoregressive approach. Furthermore, as the number of studies incorporating machine learning techniques rapidly increases, our follow-up study aims to develop a template-free GW detection pipeline by comparing multiple approaches from simple architecture to deep learning techniques.

Speaker: Sangin Kim (Chungnam National University)

Autoregressive Search from Unmodeled Gravitational Waves_2024KGWG.pdf

12:30 → 14:00 Lunch

14:00 → 15:50 Session III (14:00--15:50, Monday)

Convener: Chang-Hwan Lee (Pusan National University)

14:00 [Session III] Schwarzschild Black Hole from Perturbation Theory to All Orders

Applying the quantum field theoretic perturbiner approach to Einstein gravity, we compute the metric of a Schwarzschild black hole order by order in perturbation theory. Using recursion, this perturbative calculation can be carried out in de Donder gauge to all orders in Newton’s constant. The result is a geometric series which is convergent outside a disk of finite radius, and it agrees within its region of convergence with the known de Donder gauge metric of a Schwarzschild black hole. It thus provides a first all-order perturbative computation in Einstein gravity with a matter source. I’ll also discuss the generalization to the binary black holes.

Speaker: Dr Kanghoon Lee (Asia-Pacific Center for Theoretical Physics)

Binary black holes and scattering amplitude.pdf

14:30 [Session III] Ringdown gravitational waves and tidal deformation of black holes in non-merging close encounter

The ringdown gravitational waves resulting from the merger of binary black holes have been extensively studied and are well-known. However, our recent study has revealed that ringdown gravitational waves can also be generated in very close encounters without merging. In this talk, we will briefly introduce our research on the ringdown gravitational waves arising from non-merging close encounters, as well as the dynamical tidal deformation and ringing of black holes.

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

2024_KGWG_summer.pptx

14:50 [Session III] Characterizing Gravitational Waves from the Hyperbolic Encounter of Two Black Holes

We investigate the characteristics of gravitational waves from the hyperbolic encounters between two black holes.
We first examine the angular dependence of the trajectory-driven part of the gravitational waves in hyperbolic orbits by summing the individual modes of $\psi_4$ obtained from NR data.
To confirm whether ringdown patterns occur in each black hole, we analyze the xy-plane components of $\psi_4$ calculated in the simulations.
This study aims to determine how the gravitational waveforms from hyperbolic encounters encode physical parameters such as the masses of the black holes, their velocities, and the impact parameter, which can aid in the development of GW templates.

Speaker: Dongchan Kim (Chung-Ang University)

kgwg2024s

15:10 [Session III] Application of Deep Learning Techniques in the Identification and Classification of Eccentric Gravitational Wave Signals

In this presentation, we will delve into our ongoing project, which focuses on applying deep learning methodologies to identify and classify eccentric gravitational wave signals according to their eccentricity: non-eccentric, mildly eccentric, and strongly eccentric.

Speaker: Elahe Khalouei (Seoul National University)

15:30 [Session III] GW from Standard Model Plasma: GR vs Modified Gravity

It is well known that photon and neutrino physics cannot probe cosmological evolution beyond Big Bang Nucleosynthesis (BBN), but gravitational waves (GW) can.
In particular, the GW produced by the Standard Model of Particle Physics plasma are undoubtedly a way to probe the evolution of the universe beyond BBN. When comparing the profile of gravitational waves propagating according to the Freedman-Robertson-Walker equations with that of dEGB (dilaton-Einstein-Gauss-Bonnet scenario of
modified gravity), we observe a strong enhancement of the expected GW stochastic background produced by the primordial plasma of relativistic particles of the Standard Model. This allows us to use the bound from BBN to put in dEGB models a constraint on the reheating temperature, for a given choice of dEGB parameters. I will talk briefly about other modified scenarios.

Speaker: Liliana Velasco (Sogang University)

15:50 → 16:00 Coffee Break

16:00 → 17:30 KGWG General Assembly

• 분과세칙 승인 등 안건 처리
• IGWN(이성호), KAGRA(박준규), LIGO(강궁원) 이슈 소개 및 논의

Convener: Hyung Mok Lee (Seoul National University)

16:00 [KGWG GA] 분과세칙 승인 및 신규 회원/위원회 소개

KGWGGA202407.pptx

16:30 [KGWG GA] IGWN(이성호), KAGRA(박준규), LIGO(강궁원) 이슈 소개 및 논의

LIGO activity report.pptx

18:30 → 20:30 Dinner

Tuesday, 23 July

09:30 → 10:40 Session IV (09:00--10:40, Tuesday)

Convener: John J. Oh (NIMS)

09:30 [Session IV] Gravitational Wave Background and Pulsar Timing Arrays

Recently, Pulsar Timing Arrays (PTAs) around the world have provided strong evidence for a stochastic gravitational wave (GW) background. The second historic event defining the discovery of the GW background is imminent. We would like to review the essential knowledge a GW astronomer needs regarding the GW background. Firstly, we review the basics of the GW background and its statistical properties. Secondly, we examine the correlation method to reduce noise and the principles of pulsar timing arrays. Thirdly, we explore the implications of recent PTA results for the existence of a GW background formed by supermassive black holes. Lastly, we discuss the future perspectives of PTAs.

Speaker: Dr Chan Park (Henan Academy of Sciences)

[2024.07.23] Gravitational Wave Background and Pulsar Timing Array.pdf

10:00 [Session IV] Forecasts with Compact Binary Coalescences catalogues

The increasing number of Gravitational Wave (GW) events detected by the Ligo-Virgo-Kagra collaboration provide better constraints on models of Compact Binary Coalescences (CBCs) astrophysical populations. Said constraints notably include redshift-dependent merger rates and source parameters probability distributions (chirp masses, spins).

Therefore, generating catalogues of CBCs populations, without resorting to very intensive solvers such as population synthesis, has become more grounded with observational constraints.

In this talk, I present of brief review of GW catalogues generation before emphasizing the possible uses of such catalogues for GW detectors sensitivity design with respect to science cases. For instance, we can derive model-independent constraints on the cosmological expansion history from CBC and supernovae data, assuming various network characteristics.

Speaker: Nicolas Chartier (Seoul National University)

day2_Nicolas_kgwg_23072024.pdf

10:20 [Session IV] Impact of higher-order corrections on the measurement accuracy of NS tidal parameter

Gravitational waves emitted by binary neutron star provides information about the internal structure of neutron star, which help us verify dense matter equations of state.

We investigate how the measurement accuracy of neutron star's tidal deformability can be improved by incorporating the higher-order post-Newtonian tidal corrections.

To compute the measurement errors, we use the Fisher Matrix method which is much faster than performing the Monte Carlo simulation.

We use the TaylorF2 waveform model and assume that the neutron stars’ spin components are aligned with the binary’s orbital angular momentum.

We find that the higher-order corrections beyond 6 PN in adiabatic tides do not contribute largely, while the dynamical tides, describing Love number varying with binary's frequency, significantly reduce the measurement errors.

Speaker: Gyeongbin Park (Pusan National University)

day2_Gyeongbin_2024_KGWG_Summer_Meeting_Gyeongbin_Park.pdf

10:40 → 11:00 Coffee Break

11:00 → 12:30 Session V (11:00--12:30, Tuesday)

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

11:00 [Session V] Current Status of 7-Dimensional Telescope and Search for Optical Counterparts of GW events

The 7-Dimensional Telescope (7DT) is a multiple telescope system designed for optical follow-up observation of gravitational-wave (GW) sources and the spectral mapping survey of the sky. In this talk, we will update the current status of 7DT, including some scientific observations carried out with the telescope. Our updates will also include the 7DT construction stage that will bring 7DT from the current 12 telescope system to 16 telescope system, the data reduction pipeline, and the operation mode of the telescope. We will comment on the synergy between 7DT and other optical telescopes such as KMTNet, highlighting our recent efforts to search optical counterparts of the S240422ed event.

Speaker: Myungshin Im (Seoul National University)

day2_MyungShinIm_20240719_video.mp4

day2_MyungShinIm_7DT_KGWG24Jul23.pptx

11:30 [Session V] Application of Gaussian Mixture Modelling to coherent WaveBurst algorithm for the Burst all-sky short search

This presentation introduces an application of machine learning method, Gaussian Mixture Modelling, to the coherent WaveBurst for short duration gravitaional wave transients. The cWB+GMM methodology is applied to generic Burst all-sky short search for both LH and LHV networks in the LIGO-Virgo O3 observing run. cWB+GMM has achieved comparable sensitivities to an array of generic signal morphologies, with significant sensitivity improvements to waveforms in low Quality factor parameter space at false alarm rates of 1 per 100 years. The result implies that GMM can effectively mitigate against blip glitches, which are one of the problematic sources of noise for un-modelled GW searches.

Speaker: Jiyoon Sun (Chung-Ang University)

day2_JiyoonSun_KGWG_summer_meeting_2024.pdf

11:50 [Session V] Polarization-preserving mode matching telescope using linear astigmatism-free condition

The Mode Matching Telescope (MMT) relays the Gaussian beam waist from one location to another. A reflective confocal off-axis MMT can be optimally configured so there is no central obscuration. However, such an off-axis system may induce polarization loss, affecting not only the irradiance of the light but also the phase, while interferometry-based gravitational wave detectors strive to improve their sensitivities. We present a new type of mode matching telescope configuration where polarization is preserved by using the successive reflection condition. The successive reflection condition is equivalent to the linear astigmatism-free condition in the N-mirror system. The concept is demonstrated through an MMT design case study.

Speaker: Hojae Ahn (KHU)

day2_HojaeAhn_KGWG_LAFPolMMT_20240723.pptx

12:10 [Session V] Development of PCI for KAGRA Test Mass Characterization in KASI

KAGRA, the gravitational wave detector in Japan, is experiencing some issues from uniformity of the crystal. So it's needed to characterize samples' property to minimize this issues by selecting a good sample. We developed a photo-thermal common-path interferometer(PCI) system for KAGRA test mass characterization in KASI. A simple explanation for PCI system and current development status and results will be presented.

Speaker: Byeong-Jun Park (KASI)

day2_Byeongjun_20240722 KGWG PCI.pptx

12:30 → 14:00 Lunch

14:00 → 15:10 Session VI (14:00--15:10, Tuesday)

Convener: June Gyu Park (Yonsei University)

14:00 [Session VI] Frequency-Dependent Squeezing in Virgo and future developments with EPR strategy

Frequency-dependent squeezed (FDS) quantum states of light have been largely
found to reduce Quantum Noise in GW detectors along their entire bandwidth (10 Hz
- 10 kHz). In view of O4b, one of the major hardware improvements for Advanced
Virgo+ (AdV+) consisted in the implementation of a FDS source. It has been proven
to yield 5.6 dB of squeezing level at its best in standalone configuration, starting from
8.5 dB of generated squeezing.
The current FDS system works with the production of frequency-independent
squeezing, and the employment of a detuned linear resonator, called filter cavity
(FC), operating in vacuum and with suspended mirrors. The FC impresses the
correct frequency dependence to the incoming squeezed light. The whole system is
composed of several optical benches, both in air and in vacuum.
Although it has been widely studied both in its standalone configuration, and coupled
to the interferometer, many efforts are ongoing to further characterize and improve
its performances, even during O4b. The first part of this talk is devoted to the
description of the AdV+ FDS system and of the above-mentioned studies.
However, the necessity for a more compact FDS setup brought to alternative
proposals, for avoiding the use of an external FC, that also adds optical losses to the
beam path (~50-90 ppm for each round trip). One of them is the
Einstein-Podolsky-Rosen (EPR) conditional squeezing. In the second part of the
contribution, a table-top optical setup aimed at the experimental demonstration of
this scheme, in frequency bands suited for GW detection, will be presented. The
experiment is based on the generation of two-mode squeezing, whose beams are
quantum-entangled according to the EPR relations. Parallely, simulations are
required to realistically assess the sensitivity improvement brought by the EPR
scheme in GW detectors, comparing it with the FC performances.

Speaker: Francesco De Marco (Sapienza University of Rome & Istituto Nazionale di Fisica Nucleare, Sezione di Roma1)

day2_FrancescoDeMarco_VirgoSQZandEPR_KGWG.pdf

14:30 [Session VI] Mode matching telescope development in Kyung Hee University

We designed reflective mode-matching telescopes (MMT) for an Einstein-Podolsky-Rosen (EPR) squeezing experiment, demonstrating a mode-matching loss of less than 0.1%. EPR squeezing is a proposed method for reducing broadband quantum noise in gravitational wave detectors. To ensure precise alignment and reproducibility of the MMT, we placed optomechanics on a base plate with a reference plane. The misalignment compensation length was calculated using beam profiling results and simulations. As a result, we installed a telescope into the EPR setup and measured that the telescope worked as designed. For the next step, we are developing the active mode matching system.

Speaker: Sumin Lee (Kyung Hee University)

day2_SuminLee_KGWG2024b_240722.pptx

14:50 [Session VI] Experimental demonstration of vacuum squeezing

Quantum shot noise dominates the total noise for existing gravitational-wave (GW) detectors based on the Fabry-Perot Michelson interferometer. By squeezing the vacuum fluctuations entering a interferometer's readout port, the sensitivity of the GW detector can be significantly improved. Experimental work has recently been carried out at KASI to demonstrate the generation of squeezed vacuum. In this talk, we present the progress of the squeezing experiment at 1064 nm and upgrade plans of it.

Speaker: Chang-Hee Kim (Korea Astronomy and Space Science Institute)

day2_ChangHee_Experimental Demonstration of vacuum squeezing.pdf

15:10 → 15:30 Coffee Break

15:30 → 17:00 Session VII (15:30--17:00, Tuesday)

Convener: Hyung Mok Lee (Seoul National University)

15:30 [Session VII] Advanced Virgo detector, status and upgrades for the future observing runs

On 14 September 2015, a century after Einstein predicted their existence, the first direct detection of a Gravitational Wave (GW) from a binary black hole merger was achieved, thus opening a new window of observation on the Universe and marking the birth of GW Astronomy [1]. This important result has been possible thanks to many years of R&D efforts done by the LIGO-Virgo collaborations for the upgrade to the second generation of ground-based GW detectors [2, 3]. In the following years, during the O1, O2, O3 scientific runs, many other GW events have been detected by both Advanced LIGO (AdLIGO) and Advanced Virgo (AdVirgo) [4, 5, 6]. During August 2017, when also AdVirgo joined O2, AdLIGO and AdVirgo jointly detected GW resulting from the merger of two neutron stars [7]. This was the first event ever detected both in the gravitational and electromagnetic windows. The network of three detectors allowed to better localise the source of the GW in the sky, and it has been possible to observe the electromagnetic counterpart with roughly 84 telescopes [8]. The observing run O3 started on April 1, 2019, and ended in March 2020. After the conclusion of the O3 run, a period of upgrade of the Advanced Virgo detector was necessary before the following run O4 [9]. During this phase, the signal-recycling mirror has been installed and frequency-dependent squeezing has been implemented for a broadband reduction of the quantum noise [10, 11]. The observing run O4, which is planned to last 20 months including 2 months of commissioning breaks, started on 24 May 2023, with the two LIGO detectors, while Virgo concluded the commissioning phase and joined O4b by the 12th of April 2024.
After an introduction on gravitational wave detection, I will give an overview of the Advanced Virgo design and status. I will mainly focus on the Advanced Virgo detector upgrades implemented before the O3 and O4 runs, which made possible the detection of gravitational waves. Finally, I will describe the additional improvements planned before the future observing runs, which will push the Advanced Virgo detector sensitivity toward the maximum achievable limit.

References

[1] B.P. Abbott et al., Phys. Rev. Lett. 116, 061102 (2016)
[2] F. Acernese et al., Class. Quantum Grav., 32, 024001 (2015)
[3] J. Asii et al., Class. Quantum Grav., 32, 074001 (2015)
[4] B.P. Abbott et al., Phys. Rev. X 9, 031040 (2019)
[5] B.P. Abbott et al., Phys. Rev. X 11, 021053 (2021)
[6] B.P. Abbott et al., Phys. Rev. X 13, 041039 (2023)
[7] B.P. Abbott et al., Phys. Rev. Lett. 119, 161101 (2017)
[8] B.P. Abbott et al., ApJL 848 L12 (2017)
[9] S. Di Pace, and on behalf of the Virgo Collaboration, Phys. Scr. 96 124054 (2021)
[10] F. Acernese et al., Phys. Rev. Lett. 123, 231108 (2019)
[11] F. Acernese et al., Phys. Rev. Lett. 131, 041403 (2023)

Speaker: Sibilla Di Pace (Istituto Nazionale di Fisica Nucleare & Università degli Studi di Roma La Sapienza)

day2_Sibilla_VIR-0556A-24_AdvancedVirgoDetectorStatusAndUpgrades_KGWGM2024_DIPACES.pdf

16:00 [Session VII] Prospects for multi-messenger perspectives with current and next generation observatories

Speaker: Dr Marica Branchesi (University of Urbino)

day2_MaricaBranchesi_Korea.pptx

16:30 [Session VII] The Newtonian-noise cancellation system at the Virgo detector

Speaker: Dr Jan Harms (Gran Sasso Science Institute)

video1787570567.mp4

17:00 → 17:10 Closing Remarks