BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:A Joint Search for Circular Polarization and Kinematic Dipole Anis otropies in the Stochastic Gravitational-Wave Background DTSTART;VALUE=DATE-TIME:20260710T044500Z DTEND;VALUE=DATE-TIME:20260710T050000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-815@indico.narit.or.th DESCRIPTION:Speakers: Sevgi Karadağ (Tamkang University)\nCertain early-U niverse scenarios predict a stochastic gravitational-wave background (SGWB ) with nonzero circular polarization\, making its detection a potentially powerful probe of parity-violating physics and the physics of the primordi al Universe. In addition to polarization\, the SGWB may exhibit anisotropi es. A particularly well-motivated contribution is the kinematic dipole ind uced by the observer’s motion relative to the cosmic rest frame.\n\nIn t his work\, we develop a unified Bayesian analysis framework to jointly inv estigate circular polarization and kinematic-dipole anisotropies in the SG WB. We model the cross-correlated detector response in terms of the circul ar-polarization parameter $\\Pi$\, the spectral index $\\alpha$\, the SGWB energy-density amplitude $\\Omega_{ref}$\, and the spherical-harmonic dip ole components $\\Omega^D_{1m}$that encode directional anisotropy. The pip eline is first validated through injection–recovery tests using simulate d data for third-generation detector networks consisting of Cosmic Explore r and Einstein Telescope. We further assess the projected sensitivity of t hese future detector networks. We then apply this framework to the LIGO/Vi rgo O1–O3 cross-spectral dataset. Finding no significant evidence for an SGWB signal\, we derive constraints on the parameters related to dipole a nisotropies and circular polarization. These results establish a framework for simultaneously probing circular polarization and Doppler-induced kine matic dipole anisotropies in the SGWB\, and highlight the potential of nex t-generation gravitational-wave observatories to place substantially stron ger constraints on parity-violating and anisotropic cosmological backgroun ds.\n\nhttps://indico.narit.or.th/event/236/contributions/815/ LOCATION:Novotel URL:https://indico.narit.or.th/event/236/contributions/815/ END:VEVENT BEGIN:VEVENT SUMMARY:Special session DTSTART;VALUE=DATE-TIME:20260708T093000Z DTEND;VALUE=DATE-TIME:20260708T110000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-836@indico.narit.or.th DESCRIPTION:https://indico.narit.or.th/event/236/contributions/836/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/836/ END:VEVENT BEGIN:VEVENT SUMMARY:Cosmological and High Energy Physics implications from gravitation al-wave background searches in LIGO-Virgo-KAGRA’s O1-O4a runs DTSTART;VALUE=DATE-TIME:20260708T050000Z DTEND;VALUE=DATE-TIME:20260708T054000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-835@indico.narit.or.th DESCRIPTION:Speakers: Mairi Sakellariadou (King's College London)\nhttps:/ /indico.narit.or.th/event/236/contributions/835/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/835/ END:VEVENT BEGIN:VEVENT SUMMARY:Gravitational waves from super-radiant axion clouds DTSTART;VALUE=DATE-TIME:20260708T033000Z DTEND;VALUE=DATE-TIME:20260708T040000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-834@indico.narit.or.th DESCRIPTION:Speakers: Takahiro Tanaka (Kyoto University)\nhttps://indico.n arit.or.th/event/236/contributions/834/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/834/ END:VEVENT BEGIN:VEVENT SUMMARY:TBA DTSTART;VALUE=DATE-TIME:20260708T030000Z DTEND;VALUE=DATE-TIME:20260708T033000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-833@indico.narit.or.th DESCRIPTION:Speakers: Alvin Chua (National University of Singapore)\nhttps ://indico.narit.or.th/event/236/contributions/833/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/833/ END:VEVENT BEGIN:VEVENT SUMMARY:EFT cosmology and GWs DTSTART;VALUE=DATE-TIME:20260707T093000Z DTEND;VALUE=DATE-TIME:20260707T110000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-832@indico.narit.or.th DESCRIPTION:Speakers: Vicharit Yingcharoenrat (Chulalongkorn University)\n https://indico.narit.or.th/event/236/contributions/832/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/832/ END:VEVENT BEGIN:VEVENT SUMMARY:DA Analysis: Hands On DTSTART;VALUE=DATE-TIME:20260707T073000Z DTEND;VALUE=DATE-TIME:20260707T090000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-831@indico.narit.or.th DESCRIPTION:Speakers: Siyuan Chen (Shanghai Astronomical Observatory\, Chi nese Academy of Sciences)\nhttps://indico.narit.or.th/event/236/contributi ons/831/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/831/ END:VEVENT BEGIN:VEVENT SUMMARY:Principles of LIGO/LISA/PTAs: II DTSTART;VALUE=DATE-TIME:20260707T050000Z DTEND;VALUE=DATE-TIME:20260707T060000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-830@indico.narit.or.th DESCRIPTION:Speakers: Achamveedu Gopakumar (TIFR)\nhttps://indico.narit.o r.th/event/236/contributions/830/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/830/ END:VEVENT BEGIN:VEVENT SUMMARY:GW Instrumentation: I DTSTART;VALUE=DATE-TIME:20260707T030000Z DTEND;VALUE=DATE-TIME:20260707T043000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-829@indico.narit.or.th DESCRIPTION:Speakers: Yuki Inoue ()\nhttps://indico.narit.or.th/event/236/ contributions/829/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/829/ END:VEVENT BEGIN:VEVENT SUMMARY:Principles of LIGO/LISA/PTAs: I DTSTART;VALUE=DATE-TIME:20260706T093000Z DTEND;VALUE=DATE-TIME:20260706T110000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-828@indico.narit.or.th DESCRIPTION:Speakers: Achamveedu Gopakumar (TIFR)\nhttps://indico.narit.o r.th/event/236/contributions/828/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/828/ END:VEVENT BEGIN:VEVENT SUMMARY:DA Analysis: Hands On DTSTART;VALUE=DATE-TIME:20260706T073000Z DTEND;VALUE=DATE-TIME:20260706T090000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-827@indico.narit.or.th DESCRIPTION:Speakers: Otto A. Hannuksela (The Chinese University of Hong K ong (CUHK))\nhttps://indico.narit.or.th/event/236/contributions/827/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/827/ END:VEVENT BEGIN:VEVENT SUMMARY:GWs: Basics DTSTART;VALUE=DATE-TIME:20260706T045000Z DTEND;VALUE=DATE-TIME:20260706T061000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-826@indico.narit.or.th DESCRIPTION:Speakers: Ian Vega (University of the Philippines)\nhttps://in dico.narit.or.th/event/236/contributions/826/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/826/ END:VEVENT BEGIN:VEVENT SUMMARY:Introduction to GR DTSTART;VALUE=DATE-TIME:20260706T030000Z DTEND;VALUE=DATE-TIME:20260706T043000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-825@indico.narit.or.th DESCRIPTION:Speakers: Apimook Watcharangkool (NARIT)\nhttps://indico.narit .or.th/event/236/contributions/825/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/825/ END:VEVENT BEGIN:VEVENT SUMMARY:Characterizing Bias in Multi-Source Gravitational Wave Inference w ith LISA DTSTART;VALUE=DATE-TIME:20260708T044500Z DTEND;VALUE=DATE-TIME:20260708T050000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-812@indico.narit.or.th DESCRIPTION:Speakers: Rishav Agrawal (National University of Singapore)\nT he Laser Interferometer Space Antenna (LISA) will be the first gravitation al wave detector able\nto observe sources that emit in the millihertz regi me such as Galactic Binaries (GBs)\, Massive Black Hole Binaries (MBHBs) o r Extreme Mass Ratio Inspirals (EMRIs). Consequently\, the data stream sen t by LISA will be a superposition of an unknown number of various gravitat ional wave sources. In theory\, up to 10\,000 compact binaries\, several h undred of EMRIs and about a hundred of MBHBs are expected to be sensed by the instrument. This overlap makes inferring source parameters extremely c hallenging. \n\nThis project aims to infer the parameters of EMRIs and MBH Bs and investigate the intercorrelation between parameters of different so urces and intracorrelation among the parameters of the same source. To stu dy this\, we compare two inference strategies: a local-fit approach\, wher e individual signals are iteratively inferred and removed while treating o ther sources as noise\, and a computationally intensive global-fit approac h that jointly infers multiple sources using a combined likelihood. Our an alysis focuses on quantifying biases introduced during parameter estimatio n. Results show that EMRI signals exhibit minimal overlap with GBs and MBH Bs in the frequency domain\, suggesting they can often be analysed indepen dently. We also examine interparameter correlations across different sourc e classes and intraparametric correlations within individual sources\, fin ding negligible cross-source correlations but significant correlations amo ng EMRI parameters. These findings highlight the importance of understandi ng and mitigating inference bias for accurate population studies in future LISA observations\,Our simulations have shown promising results and paves the way for future work on multiple EMRIs characterization.\n\nhttps://in dico.narit.or.th/event/236/contributions/812/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/812/ END:VEVENT BEGIN:VEVENT SUMMARY:The Wave Nature of Gravitational-Wave Lensing and Its Opportunitie s DTSTART;VALUE=DATE-TIME:20260708T081000Z DTEND;VALUE=DATE-TIME:20260708T082500Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-824@indico.narit.or.th DESCRIPTION:Speakers: Han Gil Choi ()\nhttps://indico.narit.or.th/event/23 6/contributions/824/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/824/ END:VEVENT BEGIN:VEVENT SUMMARY:Schwarzschild black hole surrounded by Dehnen dark matter halo DTSTART;VALUE=DATE-TIME:20260705T094500Z DTEND;VALUE=DATE-TIME:20260705T101500Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-823@indico.narit.or.th DESCRIPTION:Speakers: Supakchai Ponglertsakul (Silpakorn University )\nhtt ps://indico.narit.or.th/event/236/contributions/823/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/823/ END:VEVENT BEGIN:VEVENT SUMMARY:Supermassive Black Hole Formations via Bondi Accretion of Self-Int eracting Dark Matter DTSTART;VALUE=DATE-TIME:20260705T080000Z DTEND;VALUE=DATE-TIME:20260705T083000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-822@indico.narit.or.th DESCRIPTION:Speakers: Feng-Li Lin ()\nhttps://indico.narit.or.th/event/236 /contributions/822/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/822/ END:VEVENT BEGIN:VEVENT SUMMARY:Hierarchical mergers as tracers of globular cluster formation hist ory DTSTART;VALUE=DATE-TIME:20260705T074500Z DTEND;VALUE=DATE-TIME:20260705T080000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-806@indico.narit.or.th DESCRIPTION:Speakers: Andris Dorozsmai (National Astronomical Observatory of Japan)\nThe origin of globular clusters remains one of the most importa nt open questions in astrophysics\, with essential implications for our un derstanding of galaxy formation and the early Universe. \n\nGlobular clust ers are unique sites of hierarchical black hole mergers\, where the remnan t of a previous merger undergoes a subsequent coalescence\, a process only expected in the dense dynamical environments of stellar clusters. These m ergers have distinct properties compared to binary black holes formed in i solated environments\, making them promising candidates to be clearly iden tified in future observations.\n\nUsing population synthesis models of gra vitational wave sources in globular clusters\, I show that the hierarchica l merger rate directly traces the cluster formation history. Adopting a mo del for the delay time\, defined as the time between cluster formation and the eventual black hole merger\, I demonstrate that the globular cluster formation history can be accurately inferred from hierarchical merger cata logues of third-generation detectors using a non-parametric Bayesian frame work. This will constrain the cluster formation history to unprecedented a ccuracy\, shedding light on the cluster formation efficiency across cosmic time\, the role of globular clusters in cosmic reionization\, and the phy sical conditions of high-redshift star formation. Third-generation detecto rs will therefore be unique probes of globular cluster formation and high- redshift star formation\, complementing observatories such as JWST\, Eucli d\, and the ELT.\n\nhttps://indico.narit.or.th/event/236/contributions/806 / LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/806/ END:VEVENT BEGIN:VEVENT SUMMARY:Physics-Informed Neural Network for Kilonova Light Curves Modeling DTSTART;VALUE=DATE-TIME:20260705T044500Z DTEND;VALUE=DATE-TIME:20260705T050000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-813@indico.narit.or.th DESCRIPTION:Speakers: Surojit Saha (Institute of Astronomy\, National Tsin g Hua University\, Taiwan)\nPhysics-informed neural networks (PINNs) have gained considerable importance in recent years in the domain of Astronomy \\& Astrophysics\, particularly as a potential tool to solve differential equations within the given boundary conditions\, not only for making accur ate predictions but also for providing an efficient approach for large com putations. In this work\, we have focused on solving the kilonova equation s adopted from a specific kilonova model through the direct implementation of the PINN on the differential equations and the respective boundary con ditions provided in the model. The PINN architecture is trained on differe ntial equations conditioned on certain boundary conditions\, thus learning the evolution of KNe light curves based on given ranges of physical param eters. To test the performance\, after successful training\, predictions o f the light curve for a known set of physical parameters are given as inpu t\, and a comparison is made between the true and predicted light curves. Current results point to stable training with significant recovery of the light curves\, showing a low mean squared error between them. Training and inference for the light curves are completed in under 2 hours. The ultima te goal is to develop an accurate PINN-based kilonova model for light-curv e generation and low-latency parameter estimation.\n\nhttps://indico.narit .or.th/event/236/contributions/813/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/813/ END:VEVENT BEGIN:VEVENT SUMMARY:Spinning Extreme-Mass-Ratio-Inspirals into an Astrophysical Black Hole: Onset of Chaos at Astrophysically Realistic Spin DTSTART;VALUE=DATE-TIME:20260705T043000Z DTEND;VALUE=DATE-TIME:20260705T044500Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-807@indico.narit.or.th DESCRIPTION:Speakers: Surajit Das (University of Science and Technology of China\, Hefei\, Anhui 230026\, China)\nThe forthcoming space-based gravit ational wave detectors such as LISA\, Tianqin and Taiji will unlock the lo w-frequency gravitational-wave sky\, offering an unprecedented probe into the fundamental dynamics of gravity. A prime target for such detectors is Extreme Mass Ratio Inspirals (EMRIs)—the adiabatic inspiral of a stellar -mass compact object into a supermassive black hole. While conventionally modeled as integrable geodesic motion with radiative dissipation\, this ca nonical picture is fundamentally altered when the spin of the secondary co mpact object is considered. The inclusion of spin-curvature coupling break s the integrability of the system\, opening a portal to prolonged resonanc es and deterministic chaos. We expose a critical astrophysical ingredient\ , dark matter halo\, that dramatically catalyzes this chaotic transition. We systematically investigate the orbital dynamics of a spinning test part icle around a non-spinning supermassive black hole immersed in a Hernquist dark matter profile. Our analysis reveals that the dark matter halo profo undly reshapes the effective potential\, acting as a trigger for chaos. Fo r the first time\, we demonstrate through high-resolution Poincaré maps t hat chaotic features in the orbital phase space emerge at spin parameter v alues significantly lower—and thus far more astrophysically plausible— than the upper bound previously established in the literature.\nRemarkably \, we find that these chaotic signatures are not confined to the near-hori zon regime but can manifest at large distances from the central black hole \, with their characteristic scale spanning orders of magnitude—from fin e-grained structures to gross orbital deviations. This broad spatial distr ibution and amplified sensitivity to spin fundamentally reframe the detect ability of chaos in EMRIs. Our findings suggest that the gravitational-wav e fingerprints of nonintegrability\, imprinted on signals destined for LIS A and others\, are not just a mathematical curiosity but a realistic and o bservable feature of astrophysical systems. This opens a transformative ne w window for characterizing both the spacetime geometry and the ubiquitous dark matter environments in galactic nuclei.\n\nhttps://indico.narit.or.t h/event/236/contributions/807/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/807/ END:VEVENT BEGIN:VEVENT SUMMARY:Dynamical Formation of Merging Compact Binaries DTSTART;VALUE=DATE-TIME:20260705T050000Z DTEND;VALUE=DATE-TIME:20260705T054000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-821@indico.narit.or.th DESCRIPTION:Speakers: Dong Lai ()\nhttps://indico.narit.or.th/event/236/co ntributions/821/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/821/ END:VEVENT BEGIN:VEVENT SUMMARY:Multimessenger binary black hole localisation DTSTART;VALUE=DATE-TIME:20260705T033000Z DTEND;VALUE=DATE-TIME:20260705T040000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-820@indico.narit.or.th DESCRIPTION:Speakers: Otto Hannuksela ()\nhttps://indico.narit.or.th/even t/236/contributions/820/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/820/ END:VEVENT BEGIN:VEVENT SUMMARY:Introduction to Gravitational-Wave Experiments: Exploring the Univ erse from LIGO and CHRONOS DTSTART;VALUE=DATE-TIME:20260705T030000Z DTEND;VALUE=DATE-TIME:20260705T033000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-819@indico.narit.or.th DESCRIPTION:Speakers: Yuki Inoue ()\nhttps://indico.narit.or.th/event/236/ contributions/819/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/819/ END:VEVENT BEGIN:VEVENT SUMMARY:Gravitational-wave lensing in an active galactic nucleus DTSTART;VALUE=DATE-TIME:20260705T073000Z DTEND;VALUE=DATE-TIME:20260705T074500Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-818@indico.narit.or.th DESCRIPTION:Speakers: Paul Martens (The Chinese University of Hong Kong (C UHK))\nThe dense and dynamic environments that is active galactic nuclei ( AGN) accretion disks may be a birthplace for binary black holes (BBHs). It is thus a new possible formation channel for BBHs\, which is getting more interest recently. This presentation exhibits recent results aimed at des cribing the gravitational waves (GWs) lensing of a binary merger event occ uring behind an AGN (an AGN-BBH system). Such systems present several inte resting features. They have the advantage of being simple enough for const raints to be derived with only few assumptions\, to a well controlled prec ision. Using lensing\, their relative proportion in observed GWs events sh ould be strongly constrained by future GWs observatories. In particular\, this will eventually require devising some discrimination criteria for att ributing GW events to lensing in an AGN-BBH system. Thusly\, I shall detai l the GWs signatures an AGN-BBH system can imprint on the lensed GWs param eters\, such as a Doppler shift\, that could realistically be detected in the future.\n\nhttps://indico.narit.or.th/event/236/contributions/818/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/818/ END:VEVENT BEGIN:VEVENT SUMMARY:Studying astrophysics with Pulsar Timing Arrays DTSTART;VALUE=DATE-TIME:20260708T082500Z DTEND;VALUE=DATE-TIME:20260708T084500Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-817@indico.narit.or.th DESCRIPTION:Speakers: Siyuan Chen (Shanghai Astronomical Observatory\, Chi nese Academy of Sciences)\nPulsar Timing Arrays (PTAs) are entering a new era of nano-Hertz gravitational wave (GW) astronomy with evidence for a GW signal found in several PTA data sets\, CPTA\, EPTA\, InPTA\, NANOGrav\, PPTA and MPTA. They are working together in the IPTA to combine the data s ets and analyze the truely best upcoming global PTA data set\, IPTA DR3\, to be able to conclusively confirm the detection of nano-Hertz GWs. In add ition\, the GammaPTA project is also advancing and offers a complementary observing frequency range to radio PTAs. In my presentation I will focus o n tackling the challenge of the identification and characterization of the source of the GWs.\n\nOne of the main targets are super massive black hol e binaries (SMBHBs)\, which are formed when two galaxies merge. Several pr ocesses will drive the evolution of the binary orbit. Measurements of a GW background can help to address the question on how SMBHBs evolve over a c osmic time scale. Given that direct observations in the electromagnetic sp ectrum are difficult\, we can turn to cosmological simulations for further tests. Finding an individual SMBHB as a GW source will not only allow for the possibility to distinguish different population models of SMBHBs\, bu t also for multi-messenger astrophysics. I will attempt to review the curr ent status of astrophysical interpretation efforts from the PTA community and how we will move forward into the post-detection era.\n\nhttps://indic o.narit.or.th/event/236/contributions/817/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/817/ END:VEVENT BEGIN:VEVENT SUMMARY:Towards Global EMRI Search with the f-Function DTSTART;VALUE=DATE-TIME:20260708T043000Z DTEND;VALUE=DATE-TIME:20260708T044500Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-816@indico.narit.or.th DESCRIPTION:Speakers: Davendra Hassan (National University of Singapore)\n The Laser Interferometer Space Antenna (LISA) will open a new observationa l window into the millihertz gravitational wave sky\, enabling observation s of sources previously inaccessible to ground-based detectors. One of the most anticipated is the detection of Extreme Mass Ratio Inspiral (EMRI) s ystems\, in which a stellar-mass compact object completes at least tens of thousands of orbits around a massive black hole before plunging. The resu lting gravitational waveforms carry rich harmonic structure that enables p recision studies of black holes and further tests of general relativity.\n \n However\, EMRIs pose a persistent search challenge: the likelihood su rface is plagued with non-local degeneracies\, in which physically distinc t sources can produce nearly identical waveforms\, causing standard search algorithms (such as MCMC) to converge on misleading solutions far from th e true parameters. In this work\, we investigate the f-function introduced by Chua (2022) as an alternative objective function for EMRI searches\, d esigned to exponentially suppress these false solutions. We report results that show convergence near the injected parameters for a near-threshold 2 -year EMRI signal searched over a shorter window.\n\nhttps://indico.narit. or.th/event/236/contributions/816/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/816/ END:VEVENT BEGIN:VEVENT SUMMARY:Eccentricity evolution consistency test to distinguish eccentric g ravitational-wave signals from eccentricity mimickers DTSTART;VALUE=DATE-TIME:20260705T093000Z DTEND;VALUE=DATE-TIME:20260705T094500Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-811@indico.narit.or.th DESCRIPTION:Speakers: Sajad Ahmad Bhat (Inter-University Center for Astron omy and Astrophysics (IUCAA)\, India)\nEccentric compact binary coalescenc es (CBCs) are expected to be observed in current and future gravitational- wave (GW) detector networks. Such detections are especially valuable as th ey can provide insights on the environments that nurture CBCs. However\, i t has been recently pointed out that a number of other physical and beyond -GR effects could imitate\, or be mimicked by\, eccentric CBCs. The standa rd approach to ascertain that a detected CBC is eccentric is to employ Bay esian model selection\, where the eccentric CBC hypothesis is compared aga inst other hypotheses. Such an approach is not only computationally intens ive and time-consuming\, but could also be misleading if none of the model s under consideration represent the true model. In this work\, we propose a conceptually simple but powerful method to directly confirm or reject th e eccentric hypothesis\, without needing to compare the hypothesis with th e plethora of other possible hypotheses. The key idea is that while spurio us nonzero values of eccentricity\, at some reference frequency\, could be acquired when a noneccentric CBC with additional physical/beyond-GR effec ts is recovered with an eccentric CBC waveform model\, the evolution of ec centricity with frequency will in general not be mimicked. We accordingly formulate an eccentricity evolution consistency test (EECT). The method co mpares the eccentricity recovered at some low frequency value (e.g.\, 10 H z)\, evolved to higher frequencies assuming GR\, with eccentricities recov ered at those same higher frequencies. Discrepancy between the two eccentr icities at any reference frequency would violate EECT and indicate the pre sence of a mimicker. As a proof of concept\, assuming a few eccentric CBC systems\, quasicircular CBCs with additional physics mimicking eccentricit y\, and an O4-like three-detector-network configuration\, we demonstrate t hat our proposed method is indeed able to reject mimickers at ≥ 68% conf idence\, while ensuring that truly eccentric CBCs satisfy EECT\n\nhttps:// indico.narit.or.th/event/236/contributions/811/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/811/ END:VEVENT BEGIN:VEVENT SUMMARY:A High-Precision Annual Parallax Measurement Program for PTA Pulsa rs with VLBI DTSTART;VALUE=DATE-TIME:20260708T073000Z DTEND;VALUE=DATE-TIME:20260708T075000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-810@indico.narit.or.th DESCRIPTION:Speakers: Hideyuki Kobayashi (NARIT)\nRecent international PTA observations have provided compelling evidence for a primordial backgroun d gravitational wave\, bringing its direct detection within reach. In ligh t of this progress\, we are planning precise measurements of the annual pa rallaxes of PTA pulsars in order to identify the astrophysical sources res ponsible for the background gravitational waves.\nWhile the detection of t he background gravitational waves is being pursued through correlations in pulsar timing residuals\, identifying their astrophysical origins require s precise distance measurements to individual pulsars. Accurate pulsar dis tances enable the determination of the arrival directions of the backgroun d gravitational waves. The required accuracy corresponds to the gravitatio nal-wave wavelength scale\, on the order of several parsecs.\nTo achieve t his goal\, we plan high-precision astrometric VLBI observations at 1.4 G Hz (L band) and 320 MHz (P band). In particular\, VLBI observations usin g the Square Kilometre Array (SKA)\, currently under construction\, are ex pected to provide a significant improvement in sensitivity as well as subs tantial gains in phase-referencing accuracy through multi-beam observing c apabilities.\nIn this presentation\, we report an overview of the proposed observing strategy and the current status of preparation for these VLBI a strometric observations.\n\nhttps://indico.narit.or.th/event/236/contribut ions/810/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/810/ END:VEVENT BEGIN:VEVENT SUMMARY:Continuous gravitational-wave searches for dark matter in O4 LIGO data DTSTART;VALUE=DATE-TIME:20260705T083000Z DTEND;VALUE=DATE-TIME:20260705T090000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-808@indico.narit.or.th DESCRIPTION:Speakers: Andrew Miller (ICTP - AP / University Chinese Academ y of Sciences)\nDark matter could compose ~80% of all matter in the univer se\, and yet it is completely invisible to us. Despite decades of experime nts designed to detect dark matter\, and numerous models for potential dar k matter particles\, no concrete evidence has been put forward to support the existence of beyond standard-model physics. Because of this\, it is wo rth asking whether approaching the detection of dark matter from a differe nt point of view\, that is\, via gravitational-wave interferometers\, coul d provide some insight into explaining the origin of dark matter. In this talk\, I will discuss searches for dark matter in two forms: ultralight pa rticle dark matter and sub-solar mass primordial black holes. While not de signed to search for dark matter\, gravitational-wave detectors can robust ly probe a variety of dark-matter models simultaneously\, without affectin g their sensitivity to canonical gravitational-wave sources\, and put comp etitive and sometimes even stronger constraints than those from other expe riments designed to search for dark matter.\n\nhttps://indico.narit.or.th/ event/236/contributions/808/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/808/ END:VEVENT BEGIN:VEVENT SUMMARY:Refining Gravitational Wave and Collider Physics Dialogue via Sing let Scalar Extension DTSTART;VALUE=DATE-TIME:20260708T075000Z DTEND;VALUE=DATE-TIME:20260708T081000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-805@indico.narit.or.th DESCRIPTION:Speakers: Van Que Tran (NCTS\, National Taiwan University)\nEm ploying effective field theory techniques\, we advance computations of the rmal parameters that enter predictions for the gravitational wave spectra from first-order electroweak phase transitions. Working with the real-sing let-extended Standard Model\, we utilize recent lattice simulations to con firm the existence of first-order phase transitions across the free parame ter space. For the first time\, we account for several important two-loop corrections in the high-temperature expansion for determining thermal para meters\, including the bubble wall velocity in the local thermal equilibri um approximation. We find that the requirement of completing bubble nuclea tion imposes stringent bounds on the new scalar boson mass.Moreover\, the prospects for detection by LISA require first-order phase transitions in a two-step phase transition\, which display strong sensitivity to the porta l coupling between the Higgs and the singlet. Interestingly\, signals from di-Higgs boson production at the HL-LHC probe parameter regions that sign ificantly overlap with the LISA-sensitive region\, indicating the possibil ity of accounting for both signals if detected. Conversely\, depending on the mixing angle\, a null result for di-Higgs production at the HL-LHC cou ld potentially rule out the model as an explanation for gravitational wave observations.\n\nhttps://indico.narit.or.th/event/236/contributions/805/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/805/ END:VEVENT BEGIN:VEVENT SUMMARY:Bright sirens\, dark sirens and gravitational-wave cosmography DTSTART;VALUE=DATE-TIME:20260710T050000Z DTEND;VALUE=DATE-TIME:20260710T052000Z DTSTAMP;VALUE=DATE-TIME:20261026T234422Z UID:indico-contribution-236-804@indico.narit.or.th DESCRIPTION:Speakers: Hyung Mok Lee (Seoul National Univ.)\nGravitational- wave observations of compact-binary coalescences provide a direct measurem ent of luminosity distance. If the redshift of the source can also be dete rmined\, these events can be used as standard sirens to construct a Hubble diagram and probe the expansion history of the Universe. In practice\, ho wever\, identifying the host galaxies of gravitational-wave sources is ext remely challenging because of their large sky-localization uncertainties. GW170817 was an exceptional multi-messenger event: its electromagnetic cou nterpart enabled the identification of both the binary neutron-star nature of the source and its host galaxy. Most gravitational-wave events detecte d so far\, however\, are binary black-hole mergers\, which are not expecte d to produce detectable electromagnetic radiation. These “dark sirens” therefore lack direct host-galaxy identification\, and statistical method s using galaxy catalogs have so far yielded only limited constraints on th e Hubble constant.\nThis situation could change dramatically with gravitat ional-wave detectors sensitive to frequencies lower than those accessible to current ground-based observatories. If inspiraling binary black holes c an be observed from frequencies around 0.1 Hz\, the signals may remain in band for weeks to months before merger. Over such long observation times\, the changing orientation and velocity of the detector due to the Earth’ s rotation and orbital motion induce characteristic modulations in the gra vitational-wave signal. These modulations can significantly improve measur ements of both the luminosity distance and sky position of the source.\nSe veral detector concepts targeting the mid-frequency gravitational-wave ban d have been proposed. We show that such detectors could localize some dark sirens with sufficient accuracy\, in both sky position and distance\, to uniquely identify their host galaxies. This would enable the construction of an accurate gravitational-wave Hubble diagram independent of traditiona l electromagnetic distance indicators\, opening a new route to measuring t he cosmic expansion history.\n\nhttps://indico.narit.or.th/event/236/contr ibutions/804/ LOCATION:National Astronomical Research Institute of Thailand (NARIT) Andr omeda Meeting Room URL:https://indico.narit.or.th/event/236/contributions/804/ END:VEVENT END:VCALENDAR