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George Wei-Shu Hou

Publications and source records attributed to George Wei-Shu Hou.

At least 19 recordsLinked to original sources

EveNet: A Foundation Model for Particle Collision Data Analysis

While deep learning is transforming data analysis in high-energy physics, computational challenges limit its potential. We address these challenges in the context of collider physics by introducing EveNet, an event-level foundation model pretrained on 500 million simulated collision events using a hybrid objective of self-supervised learning and physics-informed supervision. By leveraging a shared particle-cloud representation, EveNet outperforms state-of-the-art baselines across diverse tasks, including searches for heavy resonances and exotic Higgs decays, and demonstrates exceptional data efficiency in low-statistics regimes. Crucially, we validate the transferability of the model to experimental data by rediscovering the $Υ$ meson in CMS Open Data and show its capacity for precision physics through the robust extraction of quantum correlation observables stable against systematic uncertainties. These results indicate that EveNet can successfully encode the fundamental physical structure of particle interactions, which offers a unified and resource-efficient framework to accelerate discovery at current and future colliders.

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Search for Light $H^+$ via $e^+e^- \to H^+H^- \to c\bar b\bar cb$ @ ILC500

Our current {\it impasse}: no new physics seen beyond the $h(125)$ boson. We advocate the {\it general} two Higgs doublet model without $Z_2$ symmetry, allowing extra Yukawa couplings, where we present 5 clear merits. We report on the search effort at LHC for $pp \to tt\bar c$, then on the new effort of $pp \to bH^+ \to bt\bar b$ search for $H^+$, and comment on our \underline{\bf Decadal Mission} program in Taiwan. Finally, we turn to the $e^+e^- \to H^+H^- \to c\bar b\bar cb$ program at ILC500 as a {\it what-if} situation at the LHC, demonstrating light $H^+$ reconstruction without $c$-tagging. We then end with discussion and conclusion.

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$b \to sγ$, electron EDM and electroweak baryogenesis: a study in general 2HDM

We study inclusive $b \to sγ$ decay in the context of electron EDM and baryogenesis. The general 2HDM (i.e. without $Z_2$) that possesses an extra set of Yukawa matrices can drive electroweak baryogensis via $λ_t {\rm Im}ρ_{tt}$, where $ρ_{tt}$ is the extra diagonal top Yukawa coupling, with the $e$EDM constraint evaded by an exquisite flavor cancellation mechanism. We touch upon the current status of direct search for exotic $H$, $A$ and $H^+$ scalars at the LHC, while for the plethora of flavor observables in $g$2HDM, we focus on $b\to sγ$, pointing out $chiral$ enhancement of a $ρ_{tt}ρ_{bb}$ effect in $g$2HDM, which can bring in a CPV phase. We first explore the inclusive ${\cal B}(b \to sγ)$ rate, then showcase the progress that Belle II can make in the future, illustrating a potential 3$σ$ effect for the inclusive $B^+ \to X_s^+γ$ vs $B^0 \to X_s^0γ$ CPV rate difference, $ΔA_{\rm CP}$. Especially if $e$EDM emerges swiftly, perhaps one should pursue further upgrade beyond Belle II.

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CP Violation for the Heavens and the Earth

Electroweak baryogenesis can be driven by the top quark in a general two Higgs doublet model with extra Yukawa couplings. Higgs quartics provide the first order phase transition, while extra top Yukawa coupling $ρ_{tt}$ can fuel the cosmic baryon asymmetry through the $λ_t\,{\rm Im}\,ρ_{tt}$ product, with flavor-changing $ρ_{tc}$ coupling as backup. The impressive ACME 2018 bound on the electron electric dipole moment calls for an extra electron coupling $ρ_{ee}$ for exquisite cancellation among dangerous diagrams, broadening the baryogenesis solution space. The mechanism suggests that extra Yukawa couplings echo the hierarchical structure of standard Yukawa couplings. Phenomenological consequences in Higgs search and flavor physics are discussed, with $μ$ and $τ$ EDM touched upon.

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Perspectives and Outlook from HEP Window on the Universe

This brief review grew out from the HEP Concluding Talk of the {\it 25th Anniversary of the Rencontres du Vietnam}, held August 2018 in Quy Nhon. The first two-thirds gives a Summary and Highlights, or snapshot, of High Energy Physics at the end of Large Hadron Collider (LHC) Run 2. It can be view as the combined effort of the program organizers, the invited plenary speakers, and finally filtered into the present mosaic. It certainly should not be viewed as comprehensive. In the second one-third, a more personal Perspective and Outlook is given, including my take on the flavor anomalies, and why the next 3 years, the period of Long Shutdown 2 plus first year (or more) of LHC Run~3, would be {\it Bright} and {\it Flavorful}, with much hope for uncovering {\it New Physics}. We advocate extra Yukawa couplings as {\it the most likely, next, New Physics} to be tested, the effect of which is already written in our Matter Universe.

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Genuine Extra Yukawas from Extra Higgs, Implications

With a second Higgs doublet, extra Yukawa couplings $ρ_{ij}$ generally exist. Baryon Asymmetry of the Universe (BAU) can be accounted for by $ρ_{tt} \sim {\cal O}(1)$, with first order electroweak phase transition (EWPT) arising from ${\cal O}(1)$ Higgs quartic couplings. The latter can explain why the observed $h(125)$ boson so resembles the Standard Model (SM) Higgs: with coupling $η_6 \sim{\cal O}(1)$ for two-doublet mixing, the $H$--$h$ mixing angle $\cosγ\cong -η_6 v^2/(m_H^2 - m_h^2)$ is suppressed by the $CP$-even boson mass splitting $m_H^2 - m_h^2 > {\rm few}\ v^2$. The approximate alignment, together with the fermion mass-mixing pattern, controls FCNC Higgs effects at low energy. The picture can be probed by $pp \to tt\bar c$, $tt\bar t$, i.e. same-sign top and triple-top processes at the LHC.

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Neutrino Telescope Array Letter of Intent: A Large Array of High Resolution Imaging Atmospheric Cherenkov and Fluorescence Detectors for Survey of Air-showers from Cosmic Tau Neutrinos in the PeV-EeV Energy Range

This Letter of Intent (LoI) describes the outline and plan for the Neutrino Telescope Array (NTA) project. High-energy neutrinos provide unique and indisputable evidence for hadronic acceleration. Recently, IceCube has reported astronomical neutrino candidates in excess of expectation from atmospheric secondaries, but is limited by the water Cherenkov detection method. A next generation high-energy neutrino telescope should be capable of establishing indisputable evidence for cosmic high-energy neutrinos. It should not only have orders-of-magnitude larger sensitivity, but also enough pointing accuracy to probe known or unknown astronomical objects, without suffering from atmospheric secondaries. The proposed installation is a large array of compound eye stations of imaging atmospheric Cherenkov and fluorescence detectors, with wide field of view and refined observational ability of air showers from cosmic tau neutrinos in the PeV-EeV energy range. This advanced optical complex system is based substantially on the development of All-sky Survey High Resolution Air-shower detector (Ashra) and applies the tau shower Earth-skimming method to survey PeV-EeV tau neutrinos. It allows wide (30 deg x 360 deg) and deep (~400 Mpc) survey observation for PeV-EeV tau neutrinos assuming the standard GRB neutrino fluence.In addition, it enjoys the pointing accuracy of better than 0.2 deg in essentially background-free conditions. With the advanced imaging of Earth-skimming tau showers in the wide field of view, we aim for clear discovery and identification of astronomical tau neutrino sources, providing inescapable evidence of the astrophysical hadronic model for acceleration and/or propagation of extremely high energy protons in the precisely determined direction.

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Lecture about the Recent Nobel Prize -- From B Factory to the Large Hadron Collider --

These are the transcriptions of "a talk describing the theoretical insights of those honored (and the one who wasn't) and how this has led to all the physics we have been doing over the last couple of decades." After prologue, we first deal with Nambu's insight on Spontaneous Symmetry Breaking, which is rooted in an analogy with the BCS theory of superconductivity. The insight resonates to this day, as we await the LHC era to dawn. The second half starts from Gell-Mann--Lévy--Cabibbo theory, through the GIM mechanism that completed the $2\times 2$ rotations, to the insight of Kobayashi and Maskawa that CP violation could arise from the charged currents, if there exists a 3rd generation of quarks. The richness that followed defines this (FPCP) conference. We end with a perspective on a (possible) redux with a 4th generation of quarks.

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Fourth Generation Leptons and Muon $g-2$

We consider the contributions to $g_μ-2$ from fourth generation neutral and charged leptons, $N$ and $E$, at the one-loop level. Diagramatically, there are two types of contributions: boson-boson-$N$, and $E$-$E$-boson in the loop diagram. In general, the effect from $N$ is suppressed by off-diagonal PMNS matrix element $V_{Nμ}$, from the Standard Model to the Two-Higgs Doublet Models. With contribution from $E$, we consider flavor changing neutral couplings.

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B-> phi K^(*) CPV/Polarization, and Collider Implications

The hint for BSM CP violation in B-> phi K_S is now more confused, but the phi K^* polarization anomaly seems real. We present a picture based on a flavor-mixed, right-handed "strange-beauty" squark \widetilde{sb}_{1R}, driven light by the large \tilde s_R-\tilde b_R squark flavor mixing, which carries a unique new CP phase. The \widetilde{sb}_{1R} could impact on S_{phi K_S} (or alternatively S_{eta^\prime K_S}), B_s mixing, \sin2Phi_{B_s}, S_{K_Sπ^0γ} and other b-> s transitions, and can be searched for directly at the Tevatron. Whether SM or BSM, a heuristic model is given where transverse phi K^* polarization descends from the gluon helicity of on-shell b-> sg.

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Novel Effects in B System: From SUSY to Intrinsic Charm

We have entered the era of BaBar, Belle and Tevatron competition; with new hardware and unprecedented statistics reach, we must be prepared for discovering new phenomena. While these unfoldings could be coming from new physics, it could also come about as new tricks from old. We illustrate new physics with generic $bsg$ dipole and its impact on $\sin2Φ_{ϕK_S}$, and at a deeper level, the marriage of flavor symmetries and SUSY, which could impact on $B_d$, $B_s$ and $D^0$ mixings and CP violation, and possibility of a light $\widetilde{sb}$ squark. As simple unfolding, we touch upon charmless $B \to$ baryonic pair decay, with or without an associated $η^\prime/γ$. We close with the possible spectacular signal of $B\to J/ψDπ$ as a flabbergasting new trick from nonperturbative QCD: intrinsic charm of $B$.

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New Physics and Enhanced Gluonic Penguin

We discuss the historical development of the gluonic B-penguin, its sensitivity to $H^+$ effects, and $\bsg\sim$ 10--15% as a possible solution to the $\Bsl$ and $n_C$ problems. The latter and the connection of the gluonic penguin to inclusive $B\to η^\prime+ X_s$ production through the gluon anomaly, with the intriguing prospect of 10% inclusive CP asymmetries, bring us to topics of current interest.

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The Case for a Vector Glueball

We argue that the $1^{--}$ glueball $O$ is much cleaner than other glueball candidates. Anomalously large $J/ψ\to ρπ, K^*\bar K$ decays and the scalar glueball mass scale suggest that $m_{O} \simeq m_{J/ψ}$.

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Perspective on FCNC: From Rare to Well-done

We briefly review the phenomenology of FCNC, from the very rare $μ/K$, through the medium $b$, to the "pseudo-well-done" case of $b'$, extending to the possibility of large tree level FCNC at weak scale.

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Perspectives on Quark Mass and Mixing Relations

Two down-up perspectives on quark mass-mixing relations are reviewed. The modified Fritzsch path relates $V_{cb}$ and $V_{ub}$ to $M_u$, but has trouble with the low $V_{cb} \simeq 0.04$ value. The modified Wolfenstein path focuses on the change in $V_{ub}$ from $λ^3 { (ca. 1983)} \leadsto λ^4 { (ca. 1994)}$. The relations $m_d/m_s\sim m_s/m_b \sim δ\sim λ^2 \simeq | V_{cb}| \simeq | V_{us}|^2$ and $m_u/m_c\sim m_c/m_t \sim δ^2 \sim λ^4 \sim | V_{ub}|$ suggest a clean separation of the origin of $V_{KM}$: $| V_{us}| \equiv λ$ and $| V_{cb}| \equiv δ$ arise from $M_d$ while $V_{ub} \equiv Bλ^4 e^{-iϕ}$ comes from $M_u$. Five to six parameters might suffice for ten mass-mixing parameters, with $δ$ seemingly the more sensible expansion parameter, while $λ\simeq \sqrt{m_d/m_s}$ is tied empirically to $(M_d)_{11} = 0$. The approximate relations suggest a near weak scale origin of flavor.

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Prospect for Heavy Quarks Lighter than $M_W$

As the excitement surrounding the heavy top quark discovery subsides, while the expectation for LEP II physics gathers, it is a good time to sit back and reflect on whether energy regions available to us have been fully explored. We emphasize that a loophole exists where heavy quarks, perhaps the actual top quark itself, could still be hidden below $M_W$. This would typically involve scalar induced decays of the heavy quark, and could be realized in models with more than one Higgs doublet, e.g. MSSM. We illustrate such mechanisms with two Higgs doublet models, the addition of singlet quarks, as well as reconsidering a fourth family of quarks and leptons. Curiously, the present $R_b$--$R_c$ problem may be a harbinger of such scenarios. Given that LEP-II would be running soon, and in view of the large amount of data that the Tevatron has collected, we urge our experimental colleagues to conduct a critical analysis.

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Possible Resonances in $μ^+e^- \to μ^- e^+$ Collisions

We study the possibility of discovering resonances in $μ^+e^- \to μ^- e^+$ and $e^-e^- \to μ^- μ^-$ collisions. We begin with the closely related problem of muonium--antimuonium transitions, where the experimental limit has just been improved by one order of magnitude. We show that the new limit enters a rather interesting mass and Yukawa coupling domain for neutral scalar bosons. The stringent $μ\to eγ$ decay is evaded by invoking some multiplicative lepton number. Neutral and doubly charged scalar bosons give rise to distinguishable effects in muonium transitions. Alternatively, they could show up as spectacular resonance peaks in high energy $μ^+e^- \to μ^- e^+$and $e^-e^- \to μ^- μ^-$ collisions, respectively. This could occur independent of whether, but especially when, muonium-antimuonium transitions are experimentally observed.

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Possible Solution to $R_b$ -- $R_c$ Problem

We investigate the $R_b$--$R_c$ problem, starting from the more diffcult $R_c$. Introducing an isosinglet charge 2/3 quark $Q$ moves both $R_c$ and $R_b$ in the right direction. If one allows for large $c$-$Q$ {\it and} $t$-$Q$ mixings, then $R_c$ could be reduced because of singlet content of charm quark, while $R_b$ gets enhanced by a light effective top quark mass in the loop. The heavy quark observed at CDF would be dominantly a singlet quark, while the top quark is lighter than $M_W$. It is necessary to introduce a second Higgs doublet, where $H^+$ is heavy while at least one exotic neutral Higgs boson is very light. $H^+$--$h^0$ splitting accounts for $δρ$, while light $h^0$ induce fast $t\to c + h^0$ decay and hides the actual top quark at the Tevatron. The scenario can be immediately tested at LEP II via search for light top production (and toponium!). At Tevatron, one should search for exotic decay modes such as $Q\to Z + X$ or $Q\to H + X$, or measure the BR for the standard $bW$ mode. Light top search should also be renewed.

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