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BookOfAbstracts
Cosmology Frontier in Particle Physics: Astroparticle Physics and EarlyUniverse
Oct. 12-13, 2021
Book Of Abstracts
Carlos E.M. Wagner (University of Chicago, Argonne National Laboratory):
cwagner@hep.anl.gov
Title: The Muon Anomalous Magnetic Moment, Particle Physics and Cosmology
Abstract: The Muon Anomalous Magnetic Moment measured at the Fermilab and Brookhaven
Experiments may be an indication of new Physics that couples to the Standard Model leptons. In
this talk I will discuss two possible realizations of such new physics. The first one is based on a
simple scalar extension, which may be realized for scalar masses below the muon pair
production threshold. I will discuss the constraints and opportunities associated with such a
simple scenario, that may have an impact on issues as diverse as neutrino physics and
cosmology. The second realization is in the Minimal Supersymmetric extension of the Standard
Model, in which the new particles may be connected to the mechanism generating the observed
Dark Matter dentisy and may be tested in the new generation of Direct Dark Matter detection
experiments, as well as the LHC.
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George Wei-Shu Hou (National Taiwan University): wshou@phys.ntu.edu.tw
Title: CP Violation for the Heavens and the Earth
Abstract: Electroweak baryogenesis (EWBG) can be driven by the top quark in a general two
Higgs doublet model with extra Yukawa couplings but CP invariant Higgs potential. The
O(1) Higgs quartics provide the first order EW phase transition, while O(1) extra top
Yukawa coupling ρtt in the product λt lmρtt can fuel the cosmic baryon asymmetry, with
O(1) flavor-changing ρtc coupling as backup. The impressive improvement on the
electron electric dipole moment (eEDM) by ACME in 2018 calls for the presence of an
extra electron coupling ρee to bring about exquisite cancellation among dangerous
diagrams, broadening the solution space for EWBG. The mechanism suggests the new
Yukawa couplings have hierarchical structures that echo the observed pattern of
Standard Model Yukawa couplings. Phenomenological consequences in Higgs search
and flavor physics are discussed, and μ and τ EDM are also touched upon.
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Martin Spinrath (National Tsing Hua University): spinrath@phys.nthu.edu.tw
Title: Dark Matter Scattering in Optomechanical Experiments
Abstract: We will discuss our recent work on the possibility to look for dark matter scattering at
gravitational wave detectors and optomechanical setups in general. For particle dark matter this
should induce an effect very similar to Brownian motion. We will present results from a particle
physicist's and a gravitational wave astronomer's point of view.
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Yen-Hsun Lin (ASIoP): yenhsun@phys.ncku.edu.tw
Title: Exploring dark matter from neutron star capture and supernova neutrino upscattering
Abstract: The dark matter (DM) captured by the neutron star (NS) can result in the heating on the NS
surface temperature due to the DM annihilation and the kinetic process. Such heating can deviate the NS
temperature from the prediction of the standard cooling mechanism and be used to constrain various
phenomenological models with DM mass ranging from O(100) MeV and heavier. However, for DM mass
lighter than O(100) MeV, the Pauli blocking will render the DM heating irrelevant. Here we present a
new scenario that searching for the halo DM is boosted by the supernova neutrino (SNν). The boosted
DM (BDM) carried sufficient kinetic energy to be detected by the Super Kamiokande (SuperK) detector.
The SNν BDM provides a new window to probe DM lighter than MeV and extend to keV and even
beyond. The SuperK sensitivity on SNν BDM will be discussed as well.
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Hsi-Yu Schive (National Taiwan University): hyschive@phys.ntu.edu.tw
Title: Soliton Random Motion in Fuzzy Dark Matter
Abstract: Fuzzy dark matter (FDM), composed of ultralight (~10-22 eV) bosons, is a promising
dark matter candidate. It exhibits rich wave-like structures, including a soliton core surrounded
by a granular halo. In this talk, I will address the soliton random motion, including its confined
Brownian motion and density oscillations. The former leads to a new challenge against FDM
since the resulting soliton tidal field may completely disrupt the ancient star clusters in the center
of dwarf galaxies. In comparison, the gravitational heating from density oscillations is inefficient
and adiabatic since the oscillation timescale is substantially longer than the characteristic
timescale of the star cluster.
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Kfir Blum (Weizmann Institute): kfir.blum@weizmann.ac.il
Title: Looking for hints of ultralight dark matter in galaxies
Abstract: I will describe attempts to look for the imprints of ultralight dark matter in galaxies,
focusing on a density core feature (``soliton”) predicted by numerical simulations, and supported
by analytical estimates of gravitational relaxation. I will show that dozens of well-resolved
rotation curves, corresponding to dark matter-dominated galaxies spanning the same mass range
as simulated galaxies, disfavour such cores. This renders ultralight dark matter an unlikely
explanation of the cores inferred in dwarf galaxies. The soliton feature could still produce
observable signatures, even if only a small fraction of the total dark matter in the Universe is
ultralight. One interesting signature could be a positive bias in the inference of the Hubble
parameter H0 in quasar lensing time delays.
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Luca Visinelli (INFN Laboratori Nazionali di Frascati): luca.visinelli@studio.unibo.it
Title: Axion miniclusters in the Milky Way
Abstract: Axion miniclusters (AMCs) are relatively dense, gravitationally bound clumps of Dark
Matter (DM) axions. AMCs have intriguing observational consequences for Earth-based axion
detectors, for DM substructure searches with microlensing, and for radio signatures from AMC
encounters with neutron stars (NSs). However, the properties of AMCs in the Milky Way may be
drastically altered by tidal interactions with ordinary stars. We present Monte Carlo simulations
following the evolution of AMCs orbiting in the Milky Way, which can be used to estimate
the properties of AMCs throughout the Galaxy today and can be easily recast. We use this
information as a key ingredient in estimating the rate, duration, flux and sky locations of radio
signals from axion-photon conversion due to NS encounters with AMCs. The resulting
radio transients are within reach of current and future radio telescopes, opening a new avenue for
detecting QCD axion DM.
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Kin-Wang Ng (Academia Sinica): nkw@phys.sinica.edu.tw
Title: Search for Stochastic Gravitational Wave Background
Abstract: Stochastic gravitational wave background (SGWB) is one of the main science goals in
gravitational wave astronomy and cosmology. We will introduce the methods to measure the
SGWB and the current status of the observational results. Our recent studies on the strategies in
measuring the anisotropy and polarization of the SGWB will be explained.
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Yuki Inoue (National Central University): iyuki@post.kek.jp
Title: Progress of gravitational wave observation in LIGO
Abstract: The scientific approach with gravitational wave detection was established recent year.
Nowadays, we can observe the gravitational wave every 10 days in the world-wide joint
observation. The next observation will be held on 2022 summer. To improve the accuracy and
sensitivity in next observation, we are improving the calibration method of detector and
reconstruction of the gravitational wave strain. In this talk, we would like to discuss the progress
and status for the next observation.
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Jiwoo Nam (National Taiwan University): jwnam@phys.ntu.edu.tw
Title: To Unveil Mystery of the Anomalous Ultra-high Energy Upward-moving Air-showers,
TAROGE-M project
Abstract: ANITA (The ANtarctic Impulsive Transient Antenna) has reported the observation of
two anomalous upward-moving air-shower events with energies of ~0.6×10^18 eV, observed
during the first and the third flights. These events cannot be explained by standard model and
received a lot of attention with various new theoretical proposals. Reproduction of these results
with significant statistics is highly demanded by community.
We propose a new radio array experiment on the top of high mountains in Antarctica, which is
utilized to detect the upward moving air-showers. We follow the ANITA’s experimental concept,
but our approach installing antennas on high mountains has great advantages over ANITA such
as, lower the energy threshold, enhanced effective volume due to dense rock target in nearby
mountains, a long livetime, and extendibility. We propose to install 10 stations over the next 5
years to obtain sufficient sensitivity to test ANITA’s `mystery events'. The first station consisting
of 6 LPDA antennas has been installed atop Mt. Melbourne, Antarctica at an elevation of 2730
m, in Austral summer season 2019-2020. We present the scientific potential, detector design and
construction, performance of the station, as well as future plan.
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Anatoli Fedynitch (ASIoP, MHEP): afedyni@icrr.u-tokyo.ac.jp
Title: Particle physics challenges in ultra-high energy cosmic rays and atmospheric leptons
Abstract: Cosmic rays interacting with the Earths atmosphere at energies from a few GeV with
up to ZeV at the higher end. Secondaries emerging from the inelastic collisions of these Ultra-
High Energy Cosmic Rays (UHECR) re-interact with air nuclei deeper in the atmosphere,
producing atmospheric cascades or extensive air showers (EAS). Some muons and electrons
survive the transport through several kilometers of air and reach the surface. The imprint left by
the EAS in surface detectors can be used to reconstruct of the energy and nuclear mass of the
initial cosmic rays.
At present, one of the most interesting challenges is the disagreement in the estimation of the
UHECR mass composition when either using electromagnetic or muonic signals. If derived
from the observed muon number, the masses of extragalactic UHECR exceed that of iron in
contrast to what is plausibly expected from astrophysics. More technically, the observed muon
number or density exceeds the simulations by 30-60%. This phenomenon is called “the muon
puzzle” and has been recently theorized to be connected to the strangeness enhancement in
central heavy ion collisions. However, the community is far from identifying the exact origin.
A probably unrelated phenomenon is the underestimation of inclusive lepton spectra, where
muon spectrometer measurements at the surface disagree with calculations by up to 15%. Data-
driven models based on identified particle spectra from fixed target experiments like NA61 can’t
close this apparent gap. At present, the uncertainties of atmospheric neutrino fluxes are in the
range of 30-100% and can not be reduced without understanding the causes of the disagreement.
Since for underwater/-ice neutrino telescopes, such as IceCube or Baikal GVD, atmospheric
muons and neutrinos constitute the vast majority of observed events, interesting physics
opportunities be missed due to these uncertainties.
The muon excess and the high-energy atmospheric leptons are closely linked to forward
measurements at colliders since this is the relevant phase space. Due to detector limitations,
forward measurements are known to be challenging and less precise. In this talk I will give a
broader overview of these two fields and outline the future trajectory of the community in
connection to the LHC.
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Yasuhiro Yamamoto (NCTS): yasuhiro.yamamoto@ncbj.gov.pl
Title: Recent progress on light new boson search with isotope shifts
Abstract: Weakly interacting light new boson attracts large attention of cosmological and
astronomical researches.If such a particle exists, its effect can be observed in several
different objects as deviations from the standard understandings. For example, some stellar
cooling observations and galaxy evolutioncan be explained well including such a new force.
While the interaction is weak, it has been proposed a new method to search for it with precise
atomic spectroscopy. If it can be observed in a terrestrial experiment, it is a great the advantage
to confirm it. We are going to discuss the current status of the experimental and theoretical
progress.
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Basudeb Dasgupta (TIFR, Mumbai): bdasgupta@theory.tifr.res.in
Title: Cracking the Supernova Neutrino Code
Abstract: A supernova emits gargantuan numbers of neutrinos and antineutrinos of all flavors
with different luminosities and energy spectra. Due to neutrino oscillations, these different
neutrinos mix with each other. To what extent does this mixing occur? Superficially, this is an
undergraduate exercise on two-level quantum mechanical oscillations. However, it turns out to
be a very difficult (and still unanswered) question. I will review recent work on this problem and
explain why it is important to answer this question.
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Eleonora Di Valentino (Durham University): eleonora.divalentino@manchester.ac.uk
Title: Cosmological tensions: hints for a new concordance model?
Abstract: The Cosmic Microwave Background temperature and polarization anisotropy
measurements have provided strong confirmation of the LCDM model of structure formation.
Even if this model can explain incredibly well the observations in a vast range of scales and
epochs, with the increase of the experimental sensitivity, a few interesting tensions between the
cosmological probes, and anomalies in the CMB data, have emerged with different statistical
significance. While some portion of these discrepancies may be due to systematic errors, their
persistence across probes strongly hints at cracks in the standard LCDM cosmological scenario.
The most statistically significant are the Hubble constant puzzle, the S8 parameter tensions, the
Alens anomaly and a curvature of the Universe. I will review these tensions, showing some
interesting extended cosmological scenarios that can alleviate them.
International Joint Workshop on the SM and Beyond 2021
Oct. 14-15, 2021
Book Of Abstracts
Australia
Csaba Balazs (Monash University): csaba.balazs@monash.edu
Title: “GAMBIT”
Abstract: I give an update on GAMBIT, the Global And Modular Beyond-the-Standard-Models
Inference Tool. After briefly motivating global fitting, I highlight why GAMBIT is a promising
framework to help us identifying the new physics model beyond the standard models (BSM) of
particle physics and cosmology. Focusing on the physics content, I give a non-technical
introduction to the schematic structure and main features of the GAMBIT code, from the
hierarchical database, through dependency resolution, to modules and backends. I finish the talk
by describing the GAMBIT Universal Model Machine, the latest feature that GAMBIT 2.0
introduced.
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Peter Cox (U Melbourne): peter.cox@unimelb.edu.au
Title: “Theory for sub-GeV direct detection”
Abstract:
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Jan Hamann (UNSW): jan.hamann@unsw.edu.au
Title: “Optimising inflationary features the Bayesian way”
Abstract: The standard model of cosmology assumes that the primordial density fluctuations are
described by a smooth, featureless power-law spectrum. This is well-motivated by the simplest
implementations of slow-roll inflation, but there exist many extensions that predict distinct scale
dependent features in the power spectrum. We propose a new way of searching for evidence of
features in cosmic microwave background data based on the Bayesian optimisation algorithm
and show that it’s not only more efficient than previous random sampling-based analyses, but
also gives more accurate results.
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Ciaran O'Hare (University of Sydney): ciaran.ohare@sydney.edu.au
Title: “Searches for the axion, on Earth and in space”
Abstract: I will briefly review some interesting new direct and indirect searches for axions as
dark matter. Focusing on the status of axion haloscopes, I will highlight some outstanding issues
of fundamental theoretical uncertainty that the community should work towards resolving.
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China
Yong Tang (UCAS): tangy@ucas.ac.cn
Title: “Starobinsky inflation with Weyl symmetry and dark matter"
Abstract: Inflation in the early universe can generate the nearly conformal invariant fluctuation
that leads to the structures we observe at the present. The simple viable Starobinsky inflation has
an approximate global scale symmetry. We study the conformal symmetric Weyl R^2 theories
and demonstrate their equivalence to Einstein gravity coupled with a scalar and a Weyl gauge
field. The scalar field in Weyl gravity can be responsible for inflation with Starobinsky model as
the attractor, potentially distinguishable from the latter by future experiments. The intrinsic Weyl
gauge boson becomes massive once the Einstein frame is fixed, and constitutes as a dark matter
candidate with mass up to GUT scale.
===============================================================
Lei Wu (Nanjing Normal University): leiwu@njnu.edu.cn
Title: “Probing light dark matter from boosted and Migdal effects”
Abstract: Given the current strong constraints on WIMPs, search for sub-GeV Dark Matter (DM)
now is an essential task in direct detections. In order to overcome the limitation of low recoils,
enhancing ionization rate of electron from Migdal effect and modifying the velocity distribution
of DM from interaction of DM and cosmic rays are two important ways. In this work, we find
that these two ways are complementary to probe sub-GeV DM. The former can cover heavier
DM, while the latter can cover the lighter DM. Both of them can cover DM with a mass of 20
MeV to 200 MeV. Including momentum transfer effect can greatly improve the existing bounds.
===============================================================
Jiang-Hao Yu (ITP-CAS): jhyu@itp.ac.cn
Title: “Effective theory operator basis for standard model and beyond”
Abstract: Effective field theories provide systematical parametrization on new physics beyond
the standard model. It is quite challenging to write independent higher dim operators due to
higher derivatives and repeated fields. I will present a systematical and unified construction of
Lorentz, gauge, and flavor structures, which solves difficulties from EOM and IBP. The Young
tensor basis and possible ultraviolet completion will be discussed in detail.
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Qiang Yuan (Purple Mountain Observatory-CAS): yuanq@pmo.ac.cn
Title: “Opening the PeV window of the cosmos with LHAASO”
Abstract: The LHAASO (Large High Altitude Air Shower Observatory) experiment is a large
area, wide field-of-view observatory for cosmic rays and gamma-rays with hybrid detection
techniques. The construction of the full detector array was finished in July, 2021. Since April
2019, LHAASO starts the data taking with a partial array, and successfully opens the PeV
gamma-ray window with its extraordinary sensitivity. LHAASO detects a dozen of ultra-high-
energy gamma-ray sources, with the highest energy photon reaching 1.4 PeV, revealing the
existence of a population of PeVatrons in our Galaxy. Those results are expected to give very
interesting insights in astroparticle physics, advancing significantly the studies of CRcosmic ray
physics, gamma-ray astronomy, as well as new physics in the Ultra-high-energy regime.
===============================================================
Japan
Teppei Kitahara (Natoya): teppeik@kmi.nagoya-u.ac.jp
Title: “LHC phenomenology in light of R(D) and R(D * ) anomalies”
Abstract: N/A
===============================================================
Ryutaro Matsudo (KEK): matsudo@post.kek.jp
Title: “Missing final state puzzle in monopole-fermion scattering”
Abstract: It has been known that when a charged fermion scatters off a monopole, the fermion in
the s-wave component must flip its helicity. Because of this feature, if there are two or more
Dirac flavors of massless fermions, any superposition of the fermion states cannot be the final
state of the s-wave scattering as it is forbidden by conservation of the electric and flavor charges.
The unitary evolution of the state vector, on the other hand, requires some interpretation of the
final states. We solve this puzzle by finding new particle excitations in the monopole
background, where multi-fermion operators exhibit condensation. The particles are described as
excitations of closed-string configurations of the condensates.
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Go Mishima (Tohoku): go.mishima@icloud.com
Title: “Higgs pair production at LHC”
Abstract: We consider the next-to-leading order QCD correction to the Higgs boson pair
production cross section, which requires evaluation of two-loop Feynman Integrals. Exact
analytic calculation of those integrals is very difficult and not yet done up to the present, and
therefore we combine several methods to obtain reasonable evaluation of them, which are the
large-top-quark-mass approximation, the high-energy approximation (with Padé approximation),
and the numerical evaluation. This enables us to provide more reliable prediction than previous
ones, and we made it publicly available in the format of grid data.
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Kyohei Mukaida (KEK): kyohei.mukaida@kek.jp kyohei.mukaida@cern.ch
Title: “Wash-in Leptogenesis”
Abstract: In this talk, we discuss a new leptogenesis mechanism, which we dub wash-in
leptogenesis. This mechanism successfully operates at right-handed-neutrino masses as low as a
few 100 TeV, does not require any CP violation in the neutrino sector and can be implemented
even in the regime of strong wash-out.
===============================================================
Korea
Ki Young Choi (SKKU) : ckysky@gmail.com
Title: “Sterile neutrino dark matter with dipole interaction”
Abstract: I will talk about the possibility of the lightest sterile neutrino dark matter which has
dipole interaction with heavier sterile neutrinos. In this model, the lifetime can be long enough to
be a dark matter candidate without violating other constraints and the correct amount of relic
abundance can be obtained. We find that a sterile neutrino with the mass of around MeV and the
dimension-five non-renormalisable dipole interaction suppressed by 10 15 GeV can be a good
candidate of dark matter, while heavier sterile neutrinos with masses of the order of GeV can
explain the active neutrino oscillations.
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Seung J. Lee (Korea University) : s.jj.lee@gmail.com
Title: “Continuum dark matter”
Abstract: In this talk, I will present a new theory of DM, qualitatively different from any existing
proposal. I will present a theory, in which DM is made up of a novel form of matter, called
“gapped continuum”. While ordinary elementary particles have unique masses - for example,
each proton in the universe weighs exactly the same - the mass of DM states in our theory is a
continuous parameter. I will present a fully realistic model that describes this DM candidate and
its interactions with ordinary particles. The continuum DM can give striking new experimental
signatures in colliders and cosmic microwave background measurements, while the strong
suppression of direct detection signals reopens the possibility of a Z-mediated dark sector again.
===============================================================
Jong-Chul Park (Chungnam National U) : log1079@gmail.com
Title: “Detection of super-light dark matter using graphene-based sensor”
Abstract: We propose a new dark matter detection strategy that will enable the search of keV
range super-light dark matter, representing an improvement of the minimum detectable mass by
more than three orders of magnitude over the ongoing experiments. This is possible by
integrating intimately the target material, π-bond electrons in graphene, into a Josephson junction
to achieve a high sensitivity detector that can resolve a small energy exchange from dark matter
as low as ~0.1 meV. We investigate detection prospects with pg-, ng-, and ��g-scale detectors b
calculating the scattering rate between dark matter and the free electrons confined in two-
dimensional graphene with Pauli blocking factors included. We find not only that the proposed
detector can serve as a complementary probe of super-light dark matter but also achieve higher
experimental sensitivities than other proposed experiments, i.e. in having a low detectable
threshold provided the same target mass, thanks to the extremely low energy threshold of our
graphene-based Josephson junction sensor.
===============================================================
Myeonghun Park (Seoul Tech) : parc.seoultech@seoultech.ac.kr
Title: “Deep Learned Event variable for collider physics”
Abstract: To search for dark matter at the LHC in a model independent way, we need to develop
a method which can capture features of signals over a wide range of values for the unknown
model parameters, for example masses of invisible particles including dark matter. To achieve
this, we design a machine learning algorithm which is sensitive on an event-topology itself. We
illustrate the performance of our algorithm with well-known event topologies to check the
correlation between human designed optimal variable and machine-driven one.
===============================================================
Taiwan
Che-Yu Chen (IoP, Academia Sinica): b97202056@gmail.com
Title: “Testing rotating black holes without reflection symmetry”
Abstract: Rotating black holes without reflection symmetry can naturally arise in effective low-
energy theories of fundamental quantum gravity, in particular, when parity-violating interactions
are introduced. Adopting a theory-agnostic approach, we investigate the structure and property of
a rotating black hole without reflection symmetry. In the absence of reflection symmetry, the
accretion disk is in general a curved surface in shape, rather than a flat disk lying on the
equatorial plane. Furthermore, the parameter that controls the reflection asymmetry would shrink
the size of the innermost stable circular orbits, and enhance the efficiency of the black hole in
converting rest mass to radiation during the mass accretion. Some astrophysical implications,
such as the shadow cast by the black hole and the redshift associated with the disk, will also be
discussed.
===============================================================
Asuka Ito (CTC/NTHU): aito@cts.nthu.edu.tw asuka.i.aa@m.titech.ac.jp
Title: “Axion dark matter search with magnons”
Abstract: The axion provides a solution for the strong CP problem and is one of the leading
candidates for dark matter. In this talk, we propose an axion detection scheme based on quantum
nondemolition detection of magnons, i.e., quanta of collective spin excitations in a ferromagnetic
crystal. Furthermore, we give an upper limit on the coupling constant between an axion and an
electron for a certain mass of the axion dark matter.
===============================================================
Po-Yan Tseng (NTHU): tpoyan1209@gmail.com
Title: “Correlated gravitational wave and microlensing signals of macroscopic dark matter”
Abstract: Fermion dark matter particles can aggregate to form extended dark matter structures
via a first-order phase transition in which the particles get trapped in the false vacuum. We study
Fermi balls created in a phase transition induced by a generic quartic thermal effective potential.
We show that for Fermi balls of mass, 3×10 -12 ×M sun < M FB < 10 -5 ×M sun , correlated observations of
gravitational waves produced during the phase transition (at SKA/THEIA), and gravitational
microlensing caused by Fermi balls (at Subaru-HSC), can be made.
===============================================================
Di-Lun Yang (IoP, Academia Sinica): dilunyang@gmail.com
Title: “Chiral effects and transport theory in core-collapse supernovae”
Abstract: Recently, the anomalous transport phenomena of relativistic fermions associated with
chirality induced by external fields have been greatly explored in different areas of physics.
Notably, such phenomena are in connection to various quantum effects such as the chiral
anomaly and spin-orbit interaction. These chiral effects like the chiral magnetic and vortical
effects have been recently included for the study of leptonic transport in core-collapse
supernovae (CCSN). In particular, to delineate the chiral effects on neutrino radiation, a novel
chiral neutrino radiation transport equation is derived from the chiral kinetic theory, which
incorporates quantum corrections pertinent to magnetic and vortical fields in the collision term.
Such a novel theoretical framework may be applied to future simulations of CCSN. On the other
hand, through this collision term for neutrinos near thermal equilibrium, the anisotropic energy
flux of neutrinos triggered by magnetic fields is found, which could have a potential application
to pulsar kicks.
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Vietnam
Cao Hoàng Nam (Phenikaa University): nam.caohoang@phenikaa-uni.edu.vn
Title: “Vector dark matter in Kaluza-Klein gravity”
Abstract: We will present another interesting aspect of Kaluza-Klein (KK) gravity where the
excitation of spacetime from the ground state M 4 S 1 emerging in the 4D effective theory does not
play the role of a mediator of the gauge interaction as in the original description but is a natural
candidate for dark matter (DM). The stability of the DM candidate is found as a result of its
coupling form to other fields in the 5D theory (which is completely fixed by the geometric
structure of KK gravity), the nontrivial dynamics of the 4D gravitational field along the extra
dimension, and the periodic boundary condition of the extra dimension. If there is no the large
hierarchy between the bulk vacuum energy and the inverse radius of the extra dimension, the
DM candidate would be supermassive. We present the freeze-in production of the DM particles
through the gravity and Higgs portals. Then, we discuss the region of the parameter space which
is consistent with the correct DM relic abundance.
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Cao Van Son (ICISE): cvson@ifirse.icise.vn
Title: “Unravel neutrino mass spectrum and leptonic CP violation with neutrino oscillation
experiments”
Abstract: The massiveness of the neutrino, implied by the neutrino oscillation phenomena, tells
us that the Standard Model is not complete. The neutrino mass is very much smaller than other
elementary particles. However, the neutrino mass spectrum, which is crucial for deciphering the
origin of the neutrino mass, has not been established yet. Another stimulating physics being
explored with the neutrino oscillation experiments is the violation of the Charge-Parity (CP)
symmetry in the leptonic sector. The leptonic CP violation may provide an appealing explanation
of the matter-antimatter asymmetry in the Universe. The talk will highlight the recent results and
prospects for unraveling the neutrino mass spectrum and the leptonic CP violation with the
neutrino oscillation experiments.
===============================================================
Dao Thi Nhung (ICISE): dtnhung@ifirse.icise.vn
Title: “Recent developments in the NMSSMCALC”
Abstract: NMSSMCALC is a public tool for computations of the Higgs boson masses as well as
the Higgs boson decay including the state-of-the-art higher order corrections in the CP-violating
Next-to-Minimal Supersymmetric Standard Model. In this talk I present the recent developments
in the code consisting of the new two-loop corrections to the Higgs boson masses, the one-loop
electroweak, SUSYQCD corrections to the Higgs decay widths and the extension of the model to
include the inverse seesaw mechanism.
===============================================================
Le Duc Ninh (ICISE): ldninh@ifirse.icise.vn
Title: “Polarization of massive gauge bosons in diboson production at the LHC”
Abstract: Measuring the double polarization signals in diboson production at the LHC will
provide a test of the Standard Model at a very deep level. This may also help us to detect new
physics effects related to the longitudinal modes of the massive gauge bosons.
ATLAS has recently reported the first measurements of single polarizations of a massive gauge
boson in the WZ production channel. The aim is now shifting to the double polarizations of a
diboson system and we hope that they will be measured by ATLAS and CMS in the next few
years. In this talk, I will provide an experimental and theoretical status of this research direction
and present some of our latest results concerning the calculation of QCD and electroweak
corrections to polarization observables of massive gauge bosons in the Standard Model. Possible
definitions of polarization observables will also be discussed.
