Gravitational Wave Probes ofPhysics Beyond Standard
Model

Report of Contributions

https://indico.nitep.osaka-cu.ac.jp/e/130

Gravitational Wa … / Report of Contributions

What is the source of the gravitati …

Contribution ID: 16

Type: not specified

What is the source of the gravitational waves
detected by NANOGrav and other PTA experiments?
Monday, 6 November 2023 09:50 (40 minutes)
The most conservative interpretation of the nHz gravitational waves discovered by NANOGrav
and other Pulsar Timing Array (PTA) Collaborations is astrophysical, namely that they arise fromsupermassive black hole (SMBH) binaries. However, alternative cosmological models have been
proposed, including cosmic strings, phase transitions, domain walls, primordial fluctuations and“audible” axions. We compare how well these different hypotheses fit the NANOGrav data, bothin isolation and in combination with SMBH binaries, and address the questions: Which interpretations fit the data best, and which are disfavoured? We also discuss experimental signatures that
can help discriminate between different sources of the PTA GW signal, including fluctuations inthe signal strength between frequency bins, individual sources and how the PTA signal extends tohigher frequencies.

Presenter: ELLIS, John (King’s College London)
Session Classification: Opening & Morning session

August 24, 2024

Page 1

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Search for cosmological phase tran …

Contribution ID: 17

Type: not specified

Search for cosmological phase transitions throughtheir gravitational wave signals
Monday, 6 November 2023 10:30 (30 minutes)
We are currently witnessing the dawn of a new era in astrophysics and cosmology, started by the
first LIGO/Virgo/KAGRA observations of Gravitational Waves (GW). Very recently, also the detection of a stochastic background of GWs at very low frequencies was announced by the Pulsar
Timing Array collaborations. In this talk, I will discuss how such signals are produced in cosmological phase transitions examine the possible implications of current data for this source as wellas the prospects for detection in the upcoming next generation of GW experiments.

Presenter: LEWICKI, Marek (University of Warsaw)
Session Classification: Opening & Morning session

August 24, 2024

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Electroweak baryogenesis, gravita …

Contribution ID: 18

Type: not specified

Electroweak baryogenesis, gravitational Waves andcollider physics
Monday, 6 November 2023 11:30 (30 minutes)
We discuss physics of a model for electroweak baryogenesis, which satisfies theoretical and current
experimental bounds. We then discuss how the model can be tested at future experiments at spacebased gravitational wave interferometers, future colliders and also observation of primordial black
holes.

Presenter: KANEMURA, Shinya (Osaka University)
Session Classification: Phase Transition

August 24, 2024

Page 3

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Gravitational Waves from Feebly I …

Contribution ID: 19

Type: not specified

Gravitational Waves from Feebly Interacting
Particles in a First Order Phase Transition
Thursday, 9 November 2023 15:20 (20 minutes)
First order phase transitions are well-motivated and extensively studied sources of gravitational
waves (GWs) from the early Universe. The vacuum energy released during such transitions is
assumed to be transferred primarily either to the expanding walls of bubbles of true vacuum,
whose collisions source GWs, or to the surrounding plasma, producing sound waves and turbulence, which act as GW sources. In this Letter, we study an alternative possibility that has so
far not been considered: the released energy gets transferred primarily to feebly interacting particles that do not admit a fluid description but simply free-stream individually. We develop theformalism to study the production of GWs from such configurations, and demonstrate that such
GW signals have qualitatively distinct characteristics compared to conventional sources and arepotentially observable with near-future GW detectors.

Presenter: JINNO, Ryusuke (RESCEU, The University of Tokyo)
Session Classification: Topological Defects

August 24, 2024

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Opening

Contribution ID: 20

Type: not specified

Opening
Monday, 6 November 2023 09:40 (10 minutes)

Presenters: ITOYAMA, Hiroshi (NITEP); SUZUKI, Mitsuyo (Osaka Metropolitan University)
Session Classification: Opening & Morning session

August 24, 2024

Page 5

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Relation between higher- …

Contribution ID: 21

Type: not specified

Relation between higher-dimensional gauge
theories and gravitational waves from first-orderphase transitions
Monday, 6 November 2023 12:00 (20 minutes)
In this work, we investigate the relation between higher-dimensional gauge theories and stochastic gravitational wave (GW) spectrums caused by their potential. It is known that the higherdimensional gauge theories can induce the spontaneous symmetry breaking of the gauge symmetry. If the spontaneous symmetry breaking induces the first-order phase transition, the stochastic
GW can be observed in fu- ture interferometers. Through our numerical calculations, we revealthat distinctive parameters in the theories, like the compact scale, can change the GW spectrums
dynamically. We also discuss the verifiability of the theories through the GW ob- servations.

Presenter: HIROSE, Takuya (Kyushu University)
Session Classification: Phase Transition

August 24, 2024

Page 6

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Inflation, primordial black holes, a …

Contribution ID: 22

Type: not specified

Inflation, primordial black holes, and gravitational
wave background
Monday, 6 November 2023 14:00 (40 minutes)
I describe difficulty of primordial black hole formation in single field inflation and its relevance tostochastic gravitational wave observation.

Presenter: YOKOYAMA, Jun’ichi (RESCEU, The University of Tokyo)
Session Classification: Inflation

August 24, 2024

Page 7

Gravitational Wa … / Report of Contributions
Contribution ID: 23

Induced gravitational waves from …
Type: not specified

Induced gravitational waves from inflaton oscillons
Monday, 6 November 2023 14:40 (30 minutes)
We present a new way to study cosmic inflation with gravitational waves. The gravitational signal
is generated thanks to nonlinear structures in the inflaton field, called oscillons. This novel probe
allows us to test models of inflation which are challenging to test with CMB experiments.

Presenter: LOZANOV, Kaloian (Kavli IPMU)
Session Classification: Inflation

August 24, 2024

Page 8

Gravitational Wa … / Report of Contributions
Contribution ID: 24

Gravitational waves from Gauss- …
Type: not specified

Gravitational waves from Gauss-Bonnet-corrected
single-field inflation
Monday, 6 November 2023 15:10 (20 minutes)
I shall discuss gravitational wave signatures coming from a single-field inflation model in which
the inflaton couples to the Gauss-Bonnet term. When the scalar potential term and the GaussBonnet coupling term have different signs, a nontrivial fixed point arises, effectively inducing ultra
slow-roll inflation. In this case, primordial black holes can form, together with enhanced scalarinduced gravitational waves. When the scalar potential term and the Gauss-Bonnet coupling term
have same signs, on the other hand, there may exist a region where the Gauss-Bonnet term briefly
dominates. In this case, the primordial inflationary gravitational waves can be enhanced. The
detectability of the gravitational wave signals shall be discussed as well.

Presenter: KIM, Jinsu (Tongji University)
Session Classification: Inflation

August 24, 2024

Page 9

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Gravitational Waves in Gauss- …

Contribution ID: 25

Type: not specified

Gravitational Waves in Gauss-Bonnet Cosmologies
Monday, 6 November 2023 15:30 (20 minutes)
Gravitational Waves are an excellent way to probe the evolution of the universe way back before
BBN. In particular, they offer a unique way to test modified Einstein equations. At the level of theequation of motion, the simplest example of Horndeski’s theory containing higher-curvature terms
is the dilaton-Einstein-Gauss-Bonnet (dEGB) the- ory, obtained by adding a specific quadratic combination of the curvature non-minimally coupled to a scalar field. In 2303.05813 we used the
Weakly Interacting Massive Particle (WIMP) thermal decoupling scenario to explore dEGB theories. We now study the consequences of the modification of the propagation of GW when there
is a different equation of state other than radiation. In some of the scenarios studied 2303.05813
we can put limits on the reheating temperature of the universe.

Presenter: VELASCO-SEVILLA, Liliana (Sogang University)
Session Classification: Inflation

August 24, 2024

Page 10

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Closing in on primordial black holes

Contribution ID: 26

Type: not specified

Closing in on primordial black holes
Tuesday, 7 November 2023 09:00 (30 minutes)
Observational constraints have closed off all but one mass-window for primordial black holes making up all of the dark matter, and there are some specific conditions required for their productionin the first place. However, they remain a tantalising dark matter candidate because they require
no new beyond the standard model particles and they would additionally provide a lot of information about the very early universe, particularly about inflation, if found. I will highlight some key
recent results in the literature, with a focus on gravitational wave constraints, that describe how
the viable parameter space for primordial black holes making up all of the dark matter is closing
up, but also why it’s worth checking every last window for signatures of their existence.

Presenter: COLE, Philippa (University of Milano-Bicocca)
Session Classification: Primordial Black Hole

August 24, 2024

Page 11

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Primordial black hole formation fr …

Contribution ID: 27

Type: not specified

Primordial black hole formation from cosmologicalperturbations
Tuesday, 7 November 2023 09:30 (30 minutes)
After briefly reviewing the basics of primordial black holes, I would like to talk recent interesting
works on this topic, mainly focused on those of our own.

Presenter: HARADA, Tomohiro (Rikkyo University)
Session Classification: Primordial Black Hole

August 24, 2024

Page 12

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Probing the Origin of Primordial B …

Contribution ID: 28

Type: not specified

Probing the Origin of Primordial Black Holes using
Gravitational Waves
Tuesday, 7 November 2023 10:00 (20 minutes)
In this article we investigate the cumulative stochastic gravitational wave spectra as a tool to gain
insight on the creation mechanism of primordial black holes. We consider gravitational waves
from the production mechanism of primordial black holes and from the gravitational interactionsof those primordial black holes among themselves and other astrophysical black holes. We specifically focus on asynchronous bubble nucleation during a first order phase transition as the creation
mechanism. We have used two benchmark phase transitions through which the primordial black
holes and the primary gravitational wave spectra have been generated. We have considered binary
systems and close hyperbolic interactions of primordial black holes with other primordial and astrophysical black holes as the source of the secondary part of the spectra. We have shown that thisunique cumulative spectra have features which directly and indirectly depend on the specifics ofthe production mechanism.

Presenter: KUMAR BANERJEE, Indra (IISER Berhampur)
Session Classification: Primordial Black Hole

August 24, 2024

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Gravitational waves and physics of …

Contribution ID: 29

Type: not specified

Gravitational waves and physics of compact objects
Tuesday, 7 November 2023 10:50 (30 minutes)
Gravitational-wave observations have delivered a lot of information about black holes and neutron stars. Although most features are consistent with our current understanding about standard
physics, severe astronomical uncertainties leave the room of possible deviations. Future detectors with high sensitivity will also allow us to investigate more extreme conditions, e.g., ultrahighdensity. In this talk, I will review current knowledge and discuss possible future directions.

Presenter: KYUTOKU, Koutaro (Kyoto University)
Session Classification: Astrophysics

August 24, 2024

Page 14

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Contribution ID: 30

Insight into the black holes in the …
Type: not specified

Insight into the black holes in the Universe using
Gravitational Waves
Tuesday, 7 November 2023 11:20 (30 minutes)
Gravitational waves are a new observational probe that can enable data-driven tests of the fundamental laws of physics that govern the Universe. I will discuss how this avenue can explore newfrontiers that can shape our understanding of astrophysics and cosmology. I will show some latest
findings using the current gravitational wave data and discuss novel techniques for discovering
new physics from the upcoming multi-band gravitational wave observatories in synergy with theelectromagnetic observations in the coming years.

Presenter: MUKHERJEE, Suvodip (Tata Institute of Fundamental Research)
Session Classification: Astrophysics

August 24, 2024

Page 15

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Contribution ID: 31

PTAs: where we are and where we …
Type: not specified

PTAs: where we are and where we are going
Tuesday, 7 November 2023 11:50 (30 minutes)
By tracking the arrival times of radio pulses from a collection of pulsars in the Milky Way, several
pulsar timing array collaborations have found evidence for a background of gravitational waves
permeating our galaxy. In this talk, I will present this evidence and discuss possible paths forward
to discriminate between astrophysical and cosmological interpretations of this background.

Presenter: MITRIDATE, Andrea (DESY)
Session Classification: Astrophysics

August 24, 2024

Page 16

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Solitinic gravastars in a U(1) gauge- …

Contribution ID: 32

Type: not specified

Solitinic gravastars in a U(1) gauge-Higgs model
Tuesday, 7 November 2023 12:20 (20 minutes)
It is known that black holes have unsolved problems such as the singularity problem and theinformation loss problem. To solve these problems, as one of the black hole mimicker, gravastar is
proposed. Gravastar is filled by cosmological constant, and therefore metric is de-Sitter inside thestar. In usual, gravastar solutions are constructed by using Israel’s junction condition. By the way,in classical field theories with global U(1) symmetry, it is known that there are classical solutions
called nontopological solitons which the fields are spatially localized. Recently, we have found that
there exists a nontopological soliton (NTS) in the coupled system of a complex scalar field, a U(1)gauge field, and a complex Higgs field. The NTSs are filled with the cosmological constant. In thispresentation, we will show that a gravastar solution can be realized by coupling a gravitational
field to this NTS solution and discuss its properties.

Presenter: OGAWA, Tatsuya (Rikkyo University)
Session Classification: Astrophysics

August 24, 2024

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Fundamental Physics via …

Contribution ID: 33

Type: not specified

Fundamental Physics via Gravitational-Wave
Observations
Tuesday, 7 November 2023 14:00 (30 minutes)
I will review constraints on fundamental physics that have been inferred from observations ofgravitational waves, and look forward to see what new results might be obtained in the near future,
and what might be possible with future generations of gravitational-wave detectors.

Presenter: CANNON, Kipp (The University of Tokyo)
Session Classification: Laser Interferometric GW observatories

August 24, 2024

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Ground-based gravitational-wave …

Contribution ID: 34

Type: not specified

Ground-based gravitational-wave detector KAGRA –status and future prospects –Tuesday, 7 November 2023 14:30 (30 minutes)
KAGRA is a ground-based interferometric gravitational-wave detector with kilometer-scale arms
as well as LIGO and Virgo. There are two unique features in KAGRA: one is constructed at theunderground site and the other is using cryogenic sapphire mirrors for the main mirrors. Underground site provides a quite environment and is effective to reduce the seismic noise. Utilizing
cryogenic sapphire mirrors reduce thermal noise of mirrors and their suspensions, which is one ofproblematic and fundamental noises for the interferometric gravitational-wave detectors. These
two features are also important for the next-generation ground-based gravitational-wave detectors, so KAGRA is considered as the prototype of the next-generation detectors. KAGRA joined
the fourth international observing run (O4) in May, 2023 for one month. After that, KAGRA once
stopped the observing run and restarted interferometer commissioning for improving sensitivity.
In this talk, Current status of KAGRA and its future prospects are reported.

Presenter: USHIBA, Takafumi (ICRR, the University of Tokyo)
Session Classification: Laser Interferometric GW observatories

August 24, 2024

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Gravitational Wave Constraints on …

Contribution ID: 35

Type: not specified

Gravitational Wave Constraints on Properties of
Exotic Compact Objects
Tuesday, 7 November 2023 15:00 (20 minutes)
Gravitational waves from compact binary coalescences provide a unique laboratory to test properties of compact objects. As alternatives to the ordinary black holes in general relativity, various
exotic compact objects have been proposed. Some of them have largely different values of the tidal
deformability and spin-induced quadrupole moment from those of black holes, and their binaries
could be distinguished from binary black hole by using gravitational waves emitted during theirinspiral regime. We analyze gravitational waves from low-mass merger events in the GWTC-3 catalog events, detected by Advanced LIGO and Advanced Virgo. Focusing on the influence of tidal
deformability and spin-induced quadrupole moment in the inspiral waveform, we provide modelindependent constrains on deviations from the standard binary black hole case. We find that all
events that we have analyzed are consistent with the waveform of binary black hole in general relativity. Bayesian model selection shows that the hypothesis that the binary is composed of exotic
compact objects is disfavored by all events.

Presenter: NARIKAWA, Tatsuya (ICRR, The University of Tokyo)
Session Classification: Laser Interferometric GW observatories

August 24, 2024

Page 20

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Space gravitational wave antenna …

Contribution ID: 36

Type: not specified

Space gravitational wave antenna DECIGO and
B-DECIGO
Tuesday, 7 November 2023 15:20 (20 minutes)
The DECi-hertz Interferometer Gravitational-wave Observatory (DECIGO) is a future Japanesespace gravitational-wave antenna. There are many science targets that DECIGO aims to achieve,
including the detection of primordial gravitational waves, direct measurement of the accelerationof the Universe, the revelation of the formation of massive black holes, and many others. DECIGO
consists of four clusters of spacecraft, and each cluster consists of three spacecraft with three
Fabry-Perot Michelson interferometers. As a pathfinder/science mission of DECIGO, we plan tolaunch B-DECIGO to demonstrate the technologies necessary for DECIGO and to lead to fruitfulmultimessenger astronomy. B-DECIGO is a small-scale version of DECIGO with sensitivity goodenough to provide frequent detection of gravitational waves. In this talk, I will explain the targetedsciences, the mechanical and optical design, and the current status of DECIGO and B-DECIGO.

Presenter: KAWAMURA, Seiji (Nagoya University)
Session Classification: Laser Interferometric GW observatories

August 24, 2024

Page 21

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Evidence of Nano-Hertz Gravitatio …

Contribution ID: 37

Type: not specified

Evidence of Nano-Hertz Gravitational Wave
Background from Pulsar Timing Array
Thursday, 9 November 2023 09:00 (30 minutes)
Pulsar timing array is an experiment to detect gravitational waves with a frequency of nanohertz
by accurate long-term observation of pulsars. The pulsar timing array has various systematic errors such as dispersion delays caused by interstellar plasma and uncertainty in the position andmotion of solar system objects, which inhibit detection of gravitational wave signals. Recently,
there have been signs of gravitational wave background through appropriate modeling of systematic errors and correlation between pulsars. The estimated power spectrum of gravitational wave
background is consistent with one from supermassive black hole binaries, but other possibilities
such as secondary generation from density fluctuations and inflation are not excluded. In this talk,I cover the principles of pulsar timing arrays, data analysis methods and the physical interpretation of recent results. In addition, I introduce the Indian Pulsar Timing Array, which is a joint
project by India and Japan.

Presenter: TAKAHASHI, Keitaro (Kumamoto University)
Session Classification: Pulsar Timing Arrays

August 24, 2024

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Phase transition during inflation a …

Contribution ID: 38

Type: not specified

Phase transition during inflation and thegravitational wave signal at pulsar timing arrays
Thursday, 9 November 2023 09:30 (20 minutes)
We explore the possibility that the new results from the pulsar timing array (PTA) observations
could come from the secondary gravitational wave sourced by curvature perturbations generated
by a first-order phase transition during the inflation. Based on the results of a field-theoretic latticesimulation of the phase transition process, we show that the gravitational wave signal generated
through this mechanism can naturally account for the new results from the PTAs. The Bayes analysis shows that our model can well fit the power spectrum of the signal observed by NANOGrav.

Presenter: AN, Haipeng (Tsinghua University)
Session Classification: Pulsar Timing Arrays

August 24, 2024

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Hellings-Downs curve deformed b …

Contribution ID: 39

Type: not specified

Hellings-Downs curve deformed by ultralight vector
dark matter
Thursday, 9 November 2023 09:50 (20 minutes)
Pulsar timing arrays (PTAs) provide a way to detect gravitational waves (GWs) at nanohertz frequencies. To ensure the detection of GWs, observational data must exhibit the Hellings-Downs
angular correlation. It is also known that PTAs can probe ultralight dark matter. In this talk,we consider possible contamination of the Hellings-Downs angular correlation by the ultralightdark matter. We will show that ultralight vector dark matter can give rise to the deformation of
the Hellings-Downs correlation curve. Thus, the Hellings-Downs correlation curve could contain
information on ultralight dark matter with a spin.

Presenter: OMIYA, Hidetoshi (Kobe University)
Session Classification: Pulsar Timing Arrays

August 24, 2024

Page 24

Gravitational Wa … / Report of Contributionsf^2 scaling of the PTA signals, ind …

Contribution ID: 40

Type: not specifiedf^2 scaling of the PTA signals, induced gravitational
waves, and primordial black holes
Thursday, 9 November 2023 10:10 (20 minutes)
The recent pulsar timing array (PTA) data show evidence of the stochastic gravitational wave
(GW) background around the nanohertz frequency range. With the power-law fit, the data, particularly those of the NANOGrav, favor the spectral index of the cosmological strength of the GWs,
Omega_GW(f), around 2. We discuss explanations of the PTA data by GWs induced by curvature
perturbations. In particular, we interpret the f^2 scaling of the induced GWs in three ways, focusing on two of them in which the infrared tail of the GW spectrum fits the data. In the first scenario,
we assume a sharp peak of the power spectrum of the curvature perturbations, and the induced
GWs are associated with primordial black holes (PBHs) with O(10^(-4)) solar mass. Mergers ofthese PBHs emit the GW signals at higher frequencies and provide us the possibility for testing
the scenario by future GW observations if PBHs are not overproduced. In the second scenario, we
consider a cosmological era dominated by fluid with its stiff (w=1) equation of state. An advantageof this scenario is that PBH overproduction is much less likely. Thus, the PTA data offer us a clue
on a resonance-like phenomenon during inflation or a non-minimal cosmological era before the
big-bang nucleosynthesis.

Presenter: TERADA, Takahiro (Institute for Basic Science)
Session Classification: Pulsar Timing Arrays

August 24, 2024

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Contribution ID: 41

Gravitational Wave from Metastab …
Type: not specified

Gravitational Wave from Metastable SUSY Breaking
Thursday, 9 November 2023 11:00 (30 minutes)
We examine the cosmological evolution of the vacuum structure in the Intriligator-Shih-Seiberg(ISS) model of metastable supersymmetry breaking by taking into account the constraints on reheating temperature, which is needed to avoid the overproduction of gravitinos. It turns out thatthe desired phase transition from a supersymmetric vacuum to a metastable vacuum is allowed
only in the light gravitino mass region. That is achieved by either rolling down a potential or tunneling processes depending on the reheating temperature. We show that abundant gravitational
waves could be produced if a tunneling process is realized in our universe. They are detectablewith the future gravitational wave interferometers like LISA and DECIGO.

Presenter: CHU, Chong-Sun (NTHU)
Session Classification: BSM/DM

August 24, 2024

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Confinement Slingshot and Gravit …

Contribution ID: 42

Type: not specified

Confinement Slingshot and Gravitational Waves
Thursday, 9 November 2023 11:30 (20 minutes)
In this talk, I will describe a quantum field theoretic phenomenon called the gauge “slingshot” effect.
The effect occurs when a source, such as a magnetic monopole or a quark, crosses the boundary
between the Coulomb and confining phases. The corresponding gauge field of the source, either
electric or magnetic, gets confined into a flux tube stretching in the form of a string (cosmic or
a QCD type) that attaches the source to the domain wall separating the two phases. The string
tension accelerates the source towards the wall as sort of a slingshot. The slingshot phenomenonis also exhibited by various sources of other co-dimensionality, such as cosmic strings confined bydomain walls or vortices confined by Z2 strings. Apart from the field-theoretic value, the slingshot
effect has important cosmological implications, as it provides a distinct source for gravitational
waves. The effect is expected to be generic in various extensions of the standard model such as
grand unification.

Presenter: ZANTEDESCHI, Michael (Tsung-Dao Lee Institute)
Session Classification: BSM/DM

August 24, 2024

Page 27

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Exploring spin of ultralight dark m …

Contribution ID: 43

Type: not specified

Exploring spin of ultralight dark matter withgravitational wave detectors
Thursday, 9 November 2023 11:50 (20 minutes)
In this study, we propose a novel method for distinguishing spin of ultralight dark matter (ULDM)
through the ULDM search with interferometric gravitational wave detectors. ULDM, presenting
potential spin states of 0, 1, and 2, induces distinctive signatures in GW signals. We found that thefinite-time light-traveling effect dominates for spin-0 and spin-1 ULDM, resulting in unique overlap
reduction functions (ORF) distinct from those of spin-2 ULDM. This allows us to distinguish spinsof ULDM. Furthermore, our results suggest that the current constraint on the coupling constantof spin-1 ULDM to baryons becomes 30 times weaker.

Presenter: MANITA, Yusuke (Kyoto University)
Session Classification: BSM/DM

August 24, 2024

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Gravitational waves from an axion …

Contribution ID: 44

Type: not specified

Gravitational waves from an axion cloud around arotating black holeThursday, 9 November 2023 12:10 (20 minutes)
The string theory suggests the possible existence of scalar fields with tiny masses called string
axions. Such a scalar field grows around a rotating astrophysical black holes by extracting rotationenergy of that black hole due to the mechanism called the superradiant instability and forms anaxion cloud. The self-interaction of the scalar field becomes important at the final stage of that
instability, and predicting the phenomena at this stage is a difficult problem. In this talk, I introduce
our new formalism to calculate the long-term evolution of the axion cloud, and discuss the emissionof gravitational waves from that system.

Presenter: YOSHINO, Hirotaka (Osaka Metropolitan University)
Session Classification: BSM/DM

August 24, 2024

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Gravitational waves from cosmic s …

Contribution ID: 45

Type: not specified

Gravitational waves from cosmic strings
Thursday, 9 November 2023 14:00 (30 minutes)
Cosmic strings, one-dimensional topological defects that may have formed in the early universe,
predict a wide variety of gravitational wave features. I will provide an overview of the gravitational
wave signatures associated with cosmic strings.

Presenter: KUROYANAGI, Sachiko (IFT UAM-CSIC)
Session Classification: Topological Defects

August 24, 2024

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Cosmic strings, Dark Matter, and …

Contribution ID: 46

Type: not specified

Cosmic strings, Dark Matter, and Gravitational Wave
Signatures from Pure Yang-Mills Theory
Thursday, 9 November 2023 14:30 (30 minutes)
I will explain the formation of cosmic superstrings following the confinement phase transition inpure Yang-Mills theory, without invoking string theory or extra dimensions, and their significancein the production of GWs. Moreover, in pure SO(2N) gauge theory, a “baryonic glueball” is predicted as a potential candidate for dark matter. This model offers a way to potentially explain boththe observed dark matter abundance and the GW signals detected in pulsar timing arrays.

Presenter: YAMADA, Masaki (Tohoku University)
Session Classification: Topological Defects

August 24, 2024

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Generalization of the Z string and …

Contribution ID: 47

Type: not specified

Generalization of the Z string and its application
Thursday, 9 November 2023 15:00 (20 minutes)
Recent gravitational wave observations suggest the existence of cosmic strings except stable local
strings. Embedded string are candidates of such the string, and the Z string is one of them. We
have generalized the Z string for the case of SU (N ) × U (1) gauge theory and found that classicalstability of the string only depends on two mass ratios of Higgs and the gauge bosons. We show
the application of the formation condition for some models and mention the implications fromrecent results of gravitational wave observations.

Presenter: KANDA, Yukihiro (Nagoya University)
Session Classification: Topological Defects

August 24, 2024

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Gravitational Wa … / Report of Contributions
Contribution ID: 48

Induced gravitational waves from …
Type: not specified

Induced gravitational waves from a smoothcrossover and their implications on the PBH scenario
Tuesday, 7 November 2023 17:00 (1 hour)
The induced gravitational wave signal can be affected by the modification of the sound speed c2s
and the equation of state parameter w at horizon reentry. Inspired by the occurrence of phase transitions in various theories beyond the Standard Model (SM), we conducted numerical simulations
to assess the induced gravitational waves generated by a hypothetical smooth transition beyond
the SM, that softens the sound speed and equation of state while considering the case of a flat scaleinvariant power spectrum. We find that if the amplitude of the power spectrum is A ∼ O(10−3 ):i) future gravitational wave space-based detectors can detect the signal, ii) the signal is differentiated from the pure radiation case, and iii) compatibility with the hypothesis that primordial black
holes constitute the entirety of dark matter. Specifically, we observe a mass function that exhibitsa sharp peak at the maximum point of the crossover’s softening.

Presenter: ESCRIVÀ, Albert (Nagoya University)
Session Classification: Poster Session

August 24, 2024

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Stochastic gravitational wave obse …

Contribution ID: 49

Type: not specified

Stochastic gravitational wave observation using
circular polarized radiometry with global
laser-interferometer network
Tuesday, 7 November 2023 17:00 (1 hour)
Circular polarized cosmological gravitational wave background may provide evidence of possible
parity violation predicted by the e.g., Chern-Simon theory. However, Circular polarized astrophysical gravitational wave background may also exist with detectable amplitudes, if their source
distribution is anisotropic. Therefore, we need to develop a method for all-sky search for possible circular polarized astrophysical background. In this poster, we display a new method using
gravitational wave radiometry and simulation analysis was performed.

Presenter: KAKU, Izumi (Osaka Metropolitan University)
Session Classification: Poster Session

August 24, 2024

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Gravitational Wa … / Report of Contributions
Contribution ID: 50

Impact of the Global Correlated M …
Type: not specified

Impact of the Global Correlated Magnetic Noise on
Phase Transition SGWB Searches
Tuesday, 7 November 2023 17:00 (1 hour)
A stochastic gravitational wave background (SGWB) is a weak and persistent background of gravitational waves (GWs) and can provide valuable insights into the origins and evolution of theuniverse. To detect the SWGB with ground-based interferometric detectors, cross-correlations between multiple GW detectors are calculated and local noise is canceled; however, global coherent
noises, such as the Schumann resonance, remain and affect the observation. We evaluate its effecton phase transition SGWB searches based on the Fisher matrix formalism.

Presenter: WASHIMI, Tatsuki (NAOJ)
Session Classification: Poster Session

August 24, 2024

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Gravitational Wa … / Report of Contributions
Contribution ID: 51

Estimation of Acoustic Newtonian …
Type: not specified

Estimation of Acoustic Newtonian Noise for
Underground GW observatorie
Tuesday, 7 November 2023 17:00 (1 hour)
Newtonian noise (or gravity gradient noise) is one of the principal noises for ground-based GW
detectors, especially below 10 Hz. In this study, we estimate the NN caused by the acoustic field inside an underground facility for the KAGRA and further detectors based on the infrasound sensors’
data at the KAGRA site.

Presenter: WASHIMI, Tatsuki (NAOJ)
Session Classification: Poster Session

August 24, 2024

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Gravitational Wa … / Report of Contributions

Searching origin of binary black h …

Contribution ID: 52

Type: not specified

Searching origin of binary black hole withgravitational wave observation
Tuesday, 7 November 2023 17:00 (1 hour)
In 2015, gravitational wave was first detected and it was from binary black hole. After this event,many gravitational wave events from binary black hole were detected. However, including firstdetected gravitational event, origin of binary black hole observed by gravitational wave is not
solved. To solve this, first we made mass distribution of 1year gravitational wave observation andmass distribution of primordial black hole. In this poster presentation, I will present this result.

Presenter: UEMATSU, Masaki (Osaka Metropolitan University)
Session Classification: Poster Session

August 24, 2024

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