Publications (84)
Non-Standard Neutrino Physics Probed by Tokai-to-Kamioka-Korea Two-Detector Complex
Nei Cipriano Ribeiro, Takaaki Kajita, Pyungwon Ko +3
The discovery potentials of non-standard physics (NSP) which might be possessed by neutrinos are examined by taking a concrete setting of Tokai-to-Kamioka-Korea (T2KK) two detector…
Scalar and Fermion Two-component SIMP Dark Matter with an Accidental Symmetry
Shu-Yu Ho, Pyungwon Ko, Chih-Ting Lu
In this paper, we construct for the first time a two-component strongly interacting massive particles (SIMP) dark matter (DM) model, where a complex scalar and a vector-like fermio…
Color-octet mechanism in the inclusive D-wave charmonium productions in B decays
Pyungwon Ko, Jungil Lee, H. S. Song
The inclusive D-wave charmonium production rates in B decays are considered in the Bodwin-Braaten-Lepage (BBL) approach. We find that the color-octet subprocesses B->cc_(^3S_1^(8)…
Reinterpretation of LHC Results for New Physics: Status and Recommendations after Run 2
Waleed Abdallah, Shehu AbdusSalam, Azar Ahmadov +139
We report on the status of efforts to improve the reinterpretation of searches and measurements at the LHC in terms of models for new physics, in the context of the LHC Reinterpret…
Constraining Millicharged dark matter with Gravitational positivity bounds
Suro Kim, Pyungwon Ko
Gravitational positivity bounds provide consistency conditions for effective field theories with gravity. They turn out to be phenomenologically useful by providing lower bounds in…
Light Thermal Self-Interacting Dark Matter in the Shadow of Non-Standard Cosmology
Shu-Yu Ho, Pyungwon Ko, Dibyendu Nanda
In this paper, we construct a viable model for a GeV scale self-interacting dark matter (DM), where the DM was thermally produced in the early universe. Here, a new vector-like fer…
Reshuffled Strongly Interacting Massive Particle Dark Matter
Shu-Yu Ho, Pyungwon Ko, Chih-Ting Lu
In this work, we reanalyze the multi-component strongly interacting massive particle (mSIMP) scenario using an effective operator approach. As in the single-component SIMP case, th…
Stable Higgs Bosons as Cold Dark Matter
Yutaka Hosotani, Pyungwon Ko, Minoru Tanaka
In a class of the gauge-Higgs unification models the 4D neutral Higgs boson, which is a part of the extra-dimensional component of the gauge fields, becomes absolutely stable as a…
Complete analysis of photino-mediated lepton flavor violaitons in generalized supersymmetric models
Yeong Gyun Kim, Pyungwon Ko, Jae Sik Lee +1
We consider lepton flavor violations (LFV) mediated by photino as a result of the nondiagonal slepton mass matrices in general supersymmetric models. Using the experimental upper b…
Leveraging Quantum Annealer to identify an Event-topology at High Energy Colliders
Minho Kim, Pyungwon Ko, Jae-hyeon Park +1
With increasing energy and luminosity available at the Large Hadron collider (LHC), we get a chance to take a pure bottom-up approach solely based on data. This will extend the sco…
Phenomenology of charged dark matter at PAMELA/FERMI and colliders
Seungwon Baek, Pyungwon Ko
Recent data on and cosmic rays suggest that dark matter annihilate into the standard model (SM) particles through new leptophilic interaction. In this paper, we…
Almost maximally broken permutation symmetry for neutrino mass matrix
Kyungsik Kang, Sin Kyu Kang, Jihn E. Kim +1
Assuming three light neutrinos are Majorana particles, we propose mass matrix ansatz for the charged leptons and Majorana neutrinos with family symmetry broken into $S_{1}…
Resolving phenomenological problems with strongly-interacting-massive-particle models with dark vector resonances
Soo-Min Choi, Hyun Min Lee, Pyungwon Ko +1
We consider a light dark matter candidate which is produced by the freeze-out mechanism with annihilations, the so called Strongly Interacting Massive Particles (SI…
Heavy dark matter through the dilaton portal
Benjamin Fuks, Mark D. Goodsell, Dong Woo Kang +3
We re-examine current and future constraints on a heavy dilaton coupled to a simple dark sector consisting of a Majorana fermion or a Stückelberg vector field. We include three di…
Interplay between Higgs inflation and dark matter models with dark gauge symmetry
Sarif Khan, Jinsu Kim, Pyungwon Ko
We investigate dark matter phenomenology and Higgs inflation in a dark -extended model. The model features two dark matter candidates, a dark fermion and a dark vector boso…
New Approach for Measuring at Future -Factories
C. S. Kim, Pyungwon Ko, Daesung Hwang +1
It is suggested that the measurements of hadronic invariant mass () distributons in the inclusive decays can be useful in extracting the CKM matr…
Explicit Conditions for Diagnosing Tree-Level Unitarity
Jaehoon Jeong, Pyungwon Ko, Yu-Hui Zheng
We explicitly present all coupling conditions required for tree-level unitarity (tree unitarity) in theories with a finite number of massive and massless particles of spin up to 1.…
Explaining ATOMKI, , and MiniBooNE anomalies with light mediators in extended model
Sumit Ghosh, Pyungwon Ko
We consider extensions of Type-I 2HDM plus a singlet scalar , introducing a new Higgs doublet and a singlet charged under . The SM Higgs doublet…
MSSM Anatomy of the Polarization Puzzle in B --> phi K* Decays
Chao-Shang Huang, Pyungwon Ko, Xiao-Hong Wu +1
We analyze the polarization puzzle in the Minimal Supersymmetric Standard Model (MSSM) including the neutral Higgs boson (NHB) contributions. To calculate the non-f…
Low-reheating scenario in dark Higgs inflation and its impact on dark photon dark matter production
Sarif Khan, Jinsu Kim, Pyungwon Ko
We investigate dark matter (DM) phenomenology and cosmic inflation within a unified framework based on a dark gauge extension of the Standard Model (SM). The associated da…
Dark Matter Bound State Formation in Fermionic DM model with Light Dark Photon and Dark Higgs Boson
Pyungwon Ko, Toshinori Matsui, Yi-Lei Tang
If fermionic dark matter (DM) is stabilized by dark gauge symmetry that is spontaneously broken into its subgroup , the particle contents of the model becomes very rich…
Conformal Portal to Dark Matter
Kunio Kaneta, Pyungwon Ko, Wan-Il Park
We propose a new portal coupling to dark matter by taking advantage of the nonminimally coupled portal sector to the Ricci scalar. Such a portal sector conformally induces coupling…
Chiral perturbation theory vs. vector meson dominance in the decays and
Pyungwon Ko, Jungil Lee, H. S. Song
It is pointed out that the radiative decays of a meson, $\phirho$ and $\phiom$, receive dominant contributions from the pseudoscalar () exchanges. Using the ve…
Excess and DM semi-annihilation
Jongkuk Kim, Pyungwon Ko
In 2023, Belle II collaboration announced the observarion of the decay channel for the first time. This decay channel provides a clean signal with high preci…
Linking the KM3-230213A Neutrino Event to Dark Matter Decay and Gravitational Wave signals
Sarif Khan, Jongkuk Kim, Pyungwon Ko
The KM3NeT collaboration recently reported the detection of an ultra-high-energy (UHE) neutrino event, dubbed KM3-230213A. This is the first observed neutrino event with energy of…
Mass Matrix Ansatz for Degenerate Neutrinos Consistent with Solar and Atmospheric neutrino Data
Kyungsik Kang, Sin Kyu Kang, Jihn E. Kim +1
We suggest mass matrices for neutrinos and charged leptons that can explain solar and atmospheric neutrino data. The resulting flavor mixing matrix has a property that $(V_Î…
Uncovering doubly charged scalars with dominant three-body decays using machine learning
Thomas Flacke, Jeong Han Kim, Manuel Kunkel +4
We propose a deep learning-based search strategy for pair production of doubly charged scalars undergoing three-body decays to in the same-sign lepton plus multi-jet…
contribution to photon and dilepton productions from hot hadronic matter : Revisited
Jae Kwan Kim, Pyungwon Ko, Kang Young Lee +1
We consider the contribution to photon and dilepton productions from hot hadronic matter. The effective lagrangian with and discussed by Ko and Ruda…
An alternative to the standard model
Seungwon Baek, Pyungwon Ko, Wan-Il Park
We present an extension of the standard model to dark sector with an unbroken local dark symmetry. Including various singlet portal interactions provided by the standard m…
Measuring at future B-Factories
C. S. Kim, Daesung Hwang, Pyungwon Ko +1
We calculate the so--called Fermi motion parameter of ACCMM model using the variational method in a potential model approach. We also propose hadronic invariant mass distr…
Simplified Models for LHC New Physics Searches
Daniele Alves, Nima Arkani-Hamed, Sanjay Arora +92
This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS hav…
Inclusive Production of Four Charm Hadrons in e^+ e^- Annihilation at B Factories
Daekyoung Kang, Jong-Wan Lee, Jungil Lee +2
Measurements by the Belle Collaboration of the exclusive production of two charmonia in e^+ e^- annihilation differ substantially from theoretical predictions. Till now, no conclus…
A multi-component SIMP model with
Soo-Min Choi, Jinsu Kim, Pyungwon Ko +1
Multi-component dark matter scenarios are studied in the model with dark gauge symmetry that is broken into its product subgroup á la Krauss-Wilczek mech…
t-channel dark matter at the LHC -- a whitepaper
Chiara Arina, Benjamin Fuks, Luca Panizzi +67
This report, summarising work achieved in the context of the LHC Dark Matter Working Group, investigates the phenomenology of -channel dark matter models, spanning minimal setup…
A Unified Dark Matter Explanation for and the Super-Kamiokande Antineutrino Excess
Shu-Yu Ho, Jongkuk Kim, Pyungwon Ko
Recent results from Super-Kamiokande and Belle II have revealed intriguing excesses over Standard Model expectations. Super-Kamiokande observes a mild excess of -like…
More on R-parity and lepton-family number violating couplings from muon(ium) conversion, and Ïand decays
Jihn E. Kim, Pyungwon Ko, Dae-Gyu Lee
We present a new class of constraints to the lepton-family number and R-parity violating couplings from muonium conversion, ,…
Is Upsilon(3S) a pure S-wave?
Sumantra Chakravarty, Sun Myong Kim, Pyungwon Ko
Assuming the QCD multipole expansion is applicable to hadronic transitions of Upsilon(3S) into lower level bottomonia, we consider the possibility that Upsilon(3S) has a D-wave com…
Axi-Majoron : One-shot solution to most of the big puzzles of particle cosmology
Gabriela Barenboim, Pyungwon Ko, Wan-il Park
The details of the minimal cosmological standard model (MCSM) proposed in [arXiv:2403.05390.] are discussed. The model is based on the scale-symmetry and the global Peccei-Quinn(PQ…
Supersymmetric U(1)B x U(1)L model with leptophilic and leptophobic cold dark matters
Pyungwon Ko, Yuji Omura
We consider a supersymmetric model with extra gauge symmetry that are broken spontaneously. Salient features of this model are that there are three different…
B decays into two light pseudoscalar mesons and possible effects of enhanced b --> s g
Ji-Ho Jang, Yeong Gyun Kim, Pyungwon Ko
We consider the branching ratios and CP asymmetry in the B meson decays into two pseudoscalar mesons in the generalized factorization approximation. We also investigate the possibl…
Electroweak symmetry breaking and cold dark matter from hidden sector technicolor
Pyungwon Ko
We consider models with a vectorlike confining gauge theory in the hidden sector, and demonstrate that the origin of the electroweak symmetry breaking (EWSB) is due to the dimensio…
Heavy quark-philic scalar dark matter with a vector-like fermion portal
Seungwon Baek, Pyungwon Ko, Peiwen Wu
In this work we consider a real scalar dark matter interacting only with singlet Up-type quarks via a vector-like fermion which has the same qu…
and in chiral perturbation theory
Pyungwon Ko
and $\ggpipi$ are considered in chiral perturbation theory. In addition to the usual contributions, there are two operator…
Light dark matter in leptophobic Z' models
Paolo Gondolo, Pyungwon Ko, Yuji Omura
Recent experimental results in direct dark matter detection may be interpreted in terms of a dark matter particle of mass around 10 GeV/c^2. We show that the required scenario can…
A new method for extracting the weak phase gamma from B ---> D K(*) decays
Ji-Ho Jang, Pyungwon Ko
A new method to extract the weak phase is suggested by exploiting B ---> D K^{(*)} decay modes that are not Cabibbo suppressed, using the isospin relations, and ignoring the a…
AdS/QCD approach to the scale-invariant extension of the standard model with a strongly interacting hidden sector
Hisaki Hatanaka, Dong-Won Jung, Pyungwon Ko
In this paper, we revisit a scale-invariant extension of the standard model (SM) with a strongly interacting hidden sector within AdS/QCD approach. Using the AdS/QCD, we reduce the…
Recent excess and muon illuminating light dark sector with Higgs portal
Shu-Yu Ho, Jongkuk Kim, Pyungwon Ko
The Belle II collaboration recently announced that they observed the decay process for the first time. This dineutrino mode of has b…
Higgs-portal assisted Higgs inflation with a sizeable tensor-to-scalar ratio
Jinsu Kim, Pyungwon Ko, Wan-Il Park
We show that the Higgs portal interactions involving extra dark Higgs field can save generically the original Higgs inflation of the standard model (SM) from the problem of a deep…
Gravitational wave probes on self-interacting dark matter surrounding an intermediate mass black hole
Kenji Kadota, Jeong Han Kim, Pyungwon Ko +1
The presence of dark matter overdensities surrounding a black hole can influence the evolution of a binary system. The gravitational wave signals emitted by a black hole binary off…
Lepton masses and mixing angles from heterotic orbifold models
Pyungwon Ko, Tatsuo Kobayashi, Jae-hyeon Park
We systematically study the possibility for realizing realistic values of lepton mass ratios and mixing angles by using only renormalizable Yukawa couplings derived from heterotic…
Quark masses and mixing angles in heterotic orbifold models
Pyungwon Ko, Tatsuo Kobayashi, Jae-hyeon Park
We study systematically the possibility for realizing realistic values of quark mass ratios and and the mixing angle by using only renormalizable Yukaw…
Addendum to "Invisible Higgs decay width versus dark matter direct detection cross section in Higgs portal dark matter models"
Seungwon Baek, Pyungwon Ko, Wan-Il Park
This article is an addendum to Ref.~\cite{Baek:2014jga}. Here, we discuss the invisible Higgs decay width in the Higgs portal vector dark matter (VDM) model in t…
Top-philic Scalar Dark Matter with a Vector-like Fermionic Top Partner
Seungwon Baek, Pyungwon Ko, Peiwen Wu
We consider a simple extension of the Standard Model with a scalar top-philic Dark Matter (DM) coupling, apart from the Higgs portal, exclusively to the right-handed top quark…
decay as a background in search for
Pyungwon Ko, Kang Young Lee, Jae Kwan Kim
We consider a process as a standard model background to the experiment …
Color-evaporation-model calculation of e^+ e^- -> J/psi+cc-bar+X at root-s=10.6 GeV
Daekyoung Kang, Jong-Wan Lee, Jungil Lee +2
Measurements by the Belle Collaboration of the cross section for inclusive J/psi production in e^+e^- annihilation have been a serious challenge to current heavy-quarkonium theory.…
Correlation between and top quark FCNC decays in leptoquark models
Tae Jeong Kim, Pyungwon Ko, Jinmian Li +2
Some interpretations of anomaly in meson decay using leptoquark (LQ) models can also generate top quark decays through Flavor Changing Neutral Current (FCNC). In…
A simple modification of the maximal mixing scenario for three light neutrinos
Kyungsik Kang, Jihn E. Kim, Pyungwon Ko
We suggest a simple modification of the maximal mixing scenario (with permutation symmetry) for three light neutrinos. Our neutrino mass matrix has smaller permutation symmet…
Search for sterile neutrino with light gauge interactions: recasting collider, beam-dump, and neutrino telescope searches
Yongsoo Jho, Jongkuk Kim, Pyungwon Ko +1
We investigate features of the sterile neutrinos in the presence of a light gauge boson that couples to the neutrino sector. The novel bounds on the active-sterile neutrino…
Flavor properties of beauty tetraquark states with three different light quarks
Xiao-Gang He, Pyungwon Ko
Beauty tetraquark states composed of , , and , are unique that all the four valence quarks are d…
Proceedings of the second MadAnalysis 5 workshop on LHC recasting in Korea
Benjamin Fuks, Pyungwon Ko, Seung J. Lee +32
We document the activities performed during the second MadAnalysis 5 workshop on LHC recasting, that was organised in KIAS (Seoul, Korea) on February 12-20, 2020. We detail the imp…
Neutrino Theory in the Precision Era
Asmaa Abada, Gabriela Barenboim, Toni Bertólez-MartÃnez +76
This document summarises discussions on future directions in theoretical neutrino physics, which are the outcome of a neutrino theory workshop held at CERN in February 2025. The st…
Revisiting T2KK and T2KO physics potential and - beam ratio
Kaoru Hagiwara, Pyungwon Ko, Naotoshi Okamura +1
We revisit the sensitivity study of the Tokai-to-Kamioka-and-Korea (T2KK) and Tokai-to-Kamioka-and-Oki (T2KO) proposals where a water Cerenkov detector with the 100 kton fiducial v…
Hidden sector dark matter and Higgs physics
Seungwon Baek, Pyungwon Ko, Wand-Il Park +1
We consider a hidden sector dark matter, where a singlet fermion is a cold dark matter and a real singlet scalar boson is a messenger between the SM and the hidden sectors. Thi…
Final-state ÏÏinteractions in Î¥(3S)\rightarrowÎ¥(1S)ÏÏ
Sumantra Chakravarty, Sun Myong Kim, Pyungwon Ko
The spectrum and various angular distributions in $\upss$ are studied including the effects of the phase shift in the channel using the lowest order ampli…
Supernova Axion Emissivity with Resonance in Heavy Baryon Chiral Perturbation Theory
Shu-Yu Ho, Jongkuk Kim, Pyungwon Ko +1
In this paper, we evaluate the energy loss rate of supernovae induced by the axion emission process with the resonance in the heavy baryon chiral pe…
Probing SUSY-induced CP violations at B factories
Seungwon Baek, Pyungwon Ko
In the minimal supersymmetric standard model (MSSM), the μ-parameter and the trilinear coupling A_t may be generically complex and can affect various observables at B factories. I…
Light Dark Matter Showering under Broken Dark -- Revisited
Junmou Chen, Pyungwon Ko, Hsiang-nan Li +2
It was proposed recently that different chiralities of the dark matter (DM) fermion under a broken dark U(1) gauge group can lead to distinguishable signatures at the LHC through s…
Schrödinger Fields on the Plane with Chern-Simons Interactions and Generalized Self-dual Solitons
Chanju Kim, Choonkyu Lee, Pyungwon Ko +2
A general non-relativistic field theory on the plane with couplings to an arbitrary number of abelian Chern-Simons gauge fields is considered. Elementary excitations of the system…
Probing Nonstandard Neutrino Physics by Two Identical Detectors with Different Baselines
Nei Cipriano Ribeiro, Takaaki Kajita, Pyungwon Ko +3
The Kamioka-Korea two detector system is a powerful experimental setup for resolving neutrino parameter degeneracies and probing CP violation in neutrino oscillation. In this paper…
Color-octet mechanism in
Pyungwon Ko, Jungil Lee, H. S. Song
Photoproduction of is considered including the color-octet contributions from the various partial wave states, = , and . The production cr…
String-derived D4 flavor symmetry and phenomenological implications
Pyungwon Ko, Tatsuo Kobayashi, Jae-hyeon Park +1
In this paper we show how some flavor symmetries may be derived from the heterotic string, when compactified on a 6D orbifold. In the body of the paper we focus on the family…
Partially composite two-Higgs doublet model
Byungchul Chung, Kang Young Lee, Dong-Won Jung +1
In the extra dimensional scenarios with gauge fields in the bulk, the Kaluza-Klein (KK) gauge bosons can induce Nambu-Jona-Lasinio (NJL) type attractive four-fermion interactions,…
Multipositivity Constrains the Chiral Lagrangian
Clifford Cheung, Jaehoon Jeong, Pyungwon Ko +3
The chiral Lagrangian is a cornerstone of modern particle physics, offering a systematic and quantitative description of low-energy pions. Using tools from the modern scattering am…
Effects of supersymmetric CP violating phases on B \to X_s l^+ l^- and ε_K
Seungwon Baek, Pyungwon Ko
We consider effects of CP violating phases in μand A_t parameters in the effective supersymmetric standard model on B\to X_s l^+ l^- and ε_K. Scanning over the MSSM parameter spa…
Gauged Q-ball dark matter through a cosmological first-order phase transition
Siyu Jiang, Fa Peng Huang, Pyungwon Ko
As a new type of dynamical dark matter mechanism, we discuss the stability of the gauged Q-ball dark matter and its production mechanism through a cosmological first-order phase tr…
Recent Developments In Heavy Quarkonium Physics
Pyungwon Ko
Recent developments in heavy quarknoium physics are reviewed in brief, including (i) nonrelativistic QCD(NRQCD), (ii) the importance of color-octet components in the d…
Gravitational waves from first order electroweak phase transition in models with the gauge symmetry
Katsuya Hashino, Mitsuru Kakizaki, Shinya Kanemura +2
We consider a standard model extension equipped with a dark sector where the Abelian gauge symmetry is spontaneously broken by the dark Higgs mechanism. In this framewo…
The Forward Physics Facility at the High-Luminosity LHC
Jonathan L. Feng, Felix Kling, Mary Hall Reno +233
High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing L…
Multi-component dark matter and Galactic 511 keV -ray emission
Sarif Khan, Jinsu Kim, Jongkuk Kim +1
We study multi-component dark matter scenarios and the Galactic 511 keV -ray emission line signal in the framework of a local, dark extension of the Standard Model. A…
Unitarizing SIMP scenario with dark vector resonances
Soo-Min Choi, Hyun Min Lee, Pyungwon Ko +1
Dark pion is the one of the most natural and realistic model to make contact interactions among models of the Strongly Interacting Massive Particle (SIMP). In thi…
Sflavor mixing map viewed from a high scale in supersymmetric SU(5)
Pyungwon Ko, Jae-hyeon Park, Masahiro Yamaguchi
We study flavor violation in a supersymmetric SU(5) grand unification scenario in a model-independent way employing mass insertions. We examine how the quark and the lepton sector…
Explaining Data Anomalies over the NMSSM Parameter Space with Deep Learning Techniques
A. Hammad, Raymundo Ramos, Amit Chakraborty +2
Motivated by recent results from particle physics analyses, we investigate the Next-to-Minimal Supersymmetric Standard Model (NMSSM) as a framework capable of accommodating a range…
Gravitational waves and Higgs boson couplings for exploring first order phase transition in the model with a singlet scalar field
Katsuya Hashino, Mitsuru Kakizaki, Shinya Kanemura +2
We calculate the spectrum of gravitational waves originated from strongly first order electroweak phase transition in the extended Higgs model with a real singlet field. In order t…
Inclusive wave charmonium productions in decays
Pyungwon Ko, Jungil Lee, H. S. Song
The inclusive wave charmonium production rates in decays are considered using the Bodwin-Braaten-Lepage (BBL) approach, including the relativistic corrections and the color…