papers

Publications (101)

hep-ph2025

Probing Type II Seesaw Leptogenesis Through Lepton Flavor Violation

Chengcheng Han, Yijun Han, Sihui Huang +1

Lepton flavor violation (LFV) offers a powerful probe of physics beyond the Standard Model, particularly in models addressing neutrino masses and the baryon asymmetry of the univer…

hep-ph2023

Testing type II seesaw leptogenesis at the LHC

Chengcheng Han, Zhanhong Lei, Weihao Liao

Type II seesaw leptogenesis simultaneously explains the origin of neutrino masses, the baryon asymmetry of our universe, and the inflation. The Large Hadron Collider(LHC) provides…

hep-ph2022

Vacuum stability of the type II seesaw leptogenesis from inflation

Chengcheng Han, Sihui Huang, Zhanhong Lei

Recently it has been found that introducing a triplet Higgs to the standard model could provide a feasible leptogenesis to generate the baryon asymmetry of our universe, providing…

hep-ph2017

KK graviton resonance and cascade decays in warped gravity

Barry M. Dillon, Chengcheng Han, Hyun Min Lee +1

We consider the Kaluza-Klein (KK) graviton and its decays in the presence of the light radion, the modulus of extra dimension, appearing naturally light due to classical scale inva…

hep-ex2025

New Physics Search at the CEPC: a General Perspective

Xiaocong Ai, Stefan Antusch, Peter Athron +211

The Circular Electron-Positron Collider (CEPC), a proposed next-generation Higgs factory, provides new opportunities to explore physics beyond the Standard Model (SM). With its cle…

hep-ph2020

Dirac dark matter in with Stueckelberg mechanism

Chengcheng Han, M. L. López-Ibáñez, Bo Peng +1

We investigate a gauge extension of the Standard Model (SM) where the gauge boson mass is generated by the Stueckelberg mechanism. Three right-handed neutrinos are add…

hep-ph2019

Vacuum stability in stau-neutralino coannihilation in MSSM

Guang Hua Duan, Chengcheng Han, Bo Peng +2

The stau-neutralino coannihilation provides a feasible way to accommodate the observed cosmological dark matter (DM) relic density in the minimal supersymmetric standard model (MSS…

hep-ph2018

Quintessence Saves Higgs Instability

Chengcheng Han, Shi Pi, Misao Sasaki

We study a model where quintessence potential coupled to Higgs potential. We calculate the evolution of the quintessence, and track the running of the effective Higgs s…

hep-ph2023

Type-II Seesaw Leptogenesis along the Ridge

Chengcheng Han, Zhanhong Lei, Jin Min Yang

Type-II seesaw leptogenesis is a model that integrates inflation, baryon number asymmetry, and neutrino mass simultaneously. It employs the Affleck-Dine mechanism to generate lepto…

hep-ph2017

Identifying a new particle with jet substructures

Chengcheng Han, Doojin Kim, Minho Kim +3

We investigate a potential of measuring properties of a heavy resonance X, exploiting jet substructure techniques. Motivated by heavy higgs boson searches, we focus on the decays o…

physics.acc-ph2025

The Muon Collider

Carlotta Accettura, Simon Adrian, Rohit Agarwal +450

Muons offer a unique opportunity to build a compact high-energy electroweak collider at the 10 TeV scale. A Muon Collider enables direct access to the underlying simplicity of the…

cs.CV2023

Exchanging-based Multimodal Fusion with Transformer

Renyu Zhu, Chengcheng Han, Yong Qian +5

We study the problem of multimodal fusion in this paper. Recent exchanging-based methods have been proposed for vision-vision fusion, which aim to exchange embeddings learned from…

hep-ph2025

Self-interacting dark matter implied by nano-Hertz gravitational waves

Chengcheng Han, Ke-Pan Xie, Jin Min Yang +1

The self-interacting dark matter (SIDM) paradigm offers a potential solution to the small-scale structure problems faced by collision-less cold dark matter. This framework incorpor…

hep-ph2015

Accessing the core of naturalness, nearly degenerate higgsinos, at the LHC

Chengcheng Han, Doyoun Kim, Shoaib Munir +1

The presence of two light higgsinos nearly degenerate in mass is one of the important characteristics of suspersymmetric models meeting the naturalness criteria. Probing such higgs…

hep-ph2025

Cosmological Signatures of Neutrino Seesaw Mechanism

Chengcheng Han, Hong-Jian He, Linghao Song +1

The tiny neutrino masses are most naturally explained by seesaw mechanism through singlet right-handed neutrinos, which can further explain the matter-antimatter asymmetry in the U…

physics.acc-ph2023

Towards a Muon Collider

Carlotta Accettura, Dean Adams, Rohit Agarwal +294

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions a…

cs.CL2026

Skill0.5: Joint Skill Internalization and Utilization for Out-of-Distribution Generalization in Agentic Reinforcement Learning

Jiapeng Zhu, Jianxiang Yu, Yibo Zhao +5

Equipping large language models with explicit skills has emerged as a promising paradigm for enabling autonomous agents to solve complex tasks. Agent skills can be inherently divid…

hep-ph2013

Two-Higgs-doublet model with a color-triplet scalar: a joint explanation for top quark forward-backward asymmetry and Higgs decay to diphoton

Chengcheng Han, Ning Liu, Lei Wu +2

The excess of top quark forward-backward asymmetry () reported by the Tevatron and the enhancement of the Higgs decay to diphoton observed by the LHC may point to a same…

hep-ph2016

Surviving scenario of stop decays for ATLAS search

Chengcheng Han, Mihoko M. Nojiri, Michihisa Takeuchi +1

Recently ATLAS reported a excess in the stop search with channel. We try to interpret the signal by a light stop pair production in the MSSM. We find…

hep-ph2016

The diphoton resonance as a gravity mediator of dark matter

Chengcheng Han, Hyun Min Lee, Myeonghun Park +1

We consider the possibility of interpreting the recently reported diphoton excess at 750 GeV as a spin-two massive particle (such as a Kaluza-Klein graviton in warped extra-dimensi…

hep-ph2021

Muon and Co-annihilating Dark Matter in the MSSM

Peter Cox, Chengcheng Han, Tsutomu T. Yanagida

We demonstrate that the recent measurement of the anomalous magnetic moment of the muon and dark matter can be simultaneously explained within the Minimal Supersymmetric Standard M…

cs.CL2025

VitaBench: Benchmarking LLM Agents with Versatile Interactive Tasks in Real-world Applications

Wei He, Yueqing Sun, Hongyan Hao +13

As LLM-based agents are increasingly deployed in real-life scenarios, existing benchmarks fail to capture their inherent complexity of handling extensive information, leveraging di…

hep-ph2025

Probing Non-Thermal Gravitinos Through Large-Scale Structure Observations

Weiyi Deng, Liyuan Guo, Chengcheng Han +1

We investigate the effects of non-thermally produced dark matter on large-scale structure formation, focusing on the gravitino dark matter. Our analysis shows that large-scale stru…

hep-ph2013

Natural SUSY from SU(5) Orbifold GUT

Chengcheng Han, Fei Wang, Jin Min Yang

We propose a realistic 5D orbifold GUT model that can reduce to natural (or radiative natural) supersymmetry as the low energy effective theory. Supersymmetry as well as gauge symm…

hep-ph2014

A new approach for detecting compressed bino/wino at the LHC

Chengcheng Han, Lei Wu, Jin Min Yang +2

In some supersymmetric models like split supersymmetry or models with non-universal gaugino mass, bino (LSP) and winos (NLSP) may have rather small mass splitting in order to provi…

cs.LG2026

SKILL0: In-Context Agentic Reinforcement Learning for Skill Internalization

Zhengxi Lu, Zhiyuan Yao, Jinyang Wu +7

Agent skills, structured packages of procedural knowledge and executable resources that agents dynamically load at inference time, have become a reliable mechanism for augmenting L…

hep-ph2023

QCD axion dark matter and the cosmic dipole problem

Chengcheng Han

There is increasing evidence suggesting a discrepancy between the cosmic dipole observed in the number count of distant galaxies and the one derived from the cosmic microwave backg…

hep-ph2016

Heavy Fermion Bound States for Diphoton Excess at 750GeV Collider and Cosmological Constraints

Chengcheng Han, Koji Ichikawa, Shigeki Matsumoto +2

A colored heavy particle with sufficiently small width may form non-relativistic bound states when they are produced at the large hadron collider\,(LHC), and they can annihilate in…

cs.LG2024

Length Desensitization in Direct Preference Optimization

Wei Liu, Yang Bai, Chengcheng Han +5

Direct Preference Optimization (DPO) is widely utilized in the Reinforcement Learning from Human Feedback (RLHF) phase to align Large Language Models (LLMs) with human preferences,…

hep-ph2022

Type II Seesaw Leptogenesis

Neil D. Barrie, Chengcheng Han, Hitoshi Murayama

The Type II Seesaw Mechanism provides a minimal framework to explain the neutrino masses involving the introduction of a single triplet Higgs to the Standard Model. However, this s…

hep-ph2021

Muon g-2 and CP violation in MSSM

Chengcheng Han

We study the constraints of the CP violation in the muon preferred region of the minimal supersymmetric standard model assuming a universal slepton masses within first two ge…

cs.LG2026

TopoCurate:Modeling Interaction Topology for Tool-Use Agent Training

Jinluan Yang, Yuxin Liu, Zhengyu Chen +7

Training tool-use agents typically relies on outcome-based filtering: Supervised Fine-Tuning (SFT) on successful trajectories and Reinforcement Learning (RL) on pass-rate-selected…

cs.CL2024

Automated Peer Reviewing in Paper SEA: Standardization, Evaluation, and Analysis

Jianxiang Yu, Zichen Ding, Jiaqi Tan +10

In recent years, the rapid increase in scientific papers has overwhelmed traditional review mechanisms, resulting in varying quality of publications. Although existing methods have…

cs.CL2023

DialCoT Meets PPO: Decomposing and Exploring Reasoning Paths in Smaller Language Models

Chengcheng Han, Xiaowei Du, Che Zhang +4

Chain-of-Thought (CoT) prompting has proven to be effective in enhancing the reasoning capabilities of Large Language Models (LLMs) with at least 100 billion parameters. However, i…

hep-ph2025

Hybrid Type-II and Type-III seesaw model for the muon anomaly

Lei Cai, Chengcheng Han, Shi-Ping He +1

In this work we investigate the muon anomalous magnetic dipole moment in a model that extends the Standard Model with a scalar triplet and a lepton triplet. Different from p…

hep-ph2020

A scalar potential from gauge condensation and its implications

Eung Jin Chun, Chengcheng Han

We consider a scalar field whose coupling to the kinetic term of a non-abelian gauge field is set at an UV scale . Then the confinement of the gauge sector will induce a $Ï…

physics.acc-ph2025

MuCol Milestone Report No. 7: Consolidated Parameters

Rebecca Taylor, Antoine Chancé, Dario Augusto Giove +459

This document is comprised of a collection of consolidated parameters for the key parts of the muon collider. These consolidated parameters follow on from the October 2024 Prelimin…

hep-ph2020

LFV and g-2 in non-universal SUSY models with light higgsinos

Chengcheng Han, M. L. López-Ibáñez, Aurora Melis +3

We consider a supersymmetric type-I seesaw framework with non-universal scalar masses at the GUT scale to explain the long-standing discrepancy of the anomalous magnetic moment of…

cs.CL2026

GUI-CIDER: Mid-training GUI Agents via Causal Internalization and Density-aware Exemplar Reselection

Zheng Wu, Chengcheng Han, Zhengxi Lu +5

Despite the rapid progress of multimodal large language models in building Graphical User Interface (GUI) agents, their real-world task completion is fundamentally bottlenecked by…

physics.acc-ph2024

MuCol Milestone Report No. 5: Preliminary Parameters

Carlotta Accettura, Simon Adrian, Rohit Agarwal +391

This document is comprised of a collection of updated preliminary parameters for the key parts of the muon collider. The updated preliminary parameters follow on from the October 2…

cs.CL2025

MUSE: MCTS-Driven Red Teaming Framework for Enhanced Multi-Turn Dialogue Safety in Large Language Models

Siyu Yan, Long Zeng, Xuecheng Wu +6

As large language models~(LLMs) become widely adopted, ensuring their alignment with human values is crucial to prevent jailbreaks where adversaries manipulate models to produce ha…

cs.CL2023

When Gradient Descent Meets Derivative-Free Optimization: A Match Made in Black-Box Scenario

Chengcheng Han, Liqing Cui, Renyu Zhu +5

Large pre-trained language models (PLMs) have garnered significant attention for their versatility and potential for solving a wide spectrum of natural language processing (NLP) ta…

hep-ph2022

Affleck-Dine Leptogenesis from Higgs Inflation

Neil D. Barrie, Chengcheng Han, Hitoshi Murayama

We find that the triplet Higgs of the Type II seesaw mechanism can simultaneously generate the neutrino masses and observed baryon asymmetry, while playing a role in inflation. We…

astro-ph.CO2025

Curvature Perturbations from Higgs Modulated Reheating

Weiyi Deng, Chengcheng Han, Zhanhong Lei +1

In this work we investigate curvature perturbations and non-Gaussianity arising from Higgs modulated reheating in the early Universe. We employ three different methods -- the perio…

hep-ph2014

SUSY induced top quark FCNC decay after Run I of LHC

Junjie Cao, Chengcheng Han, Lei Wu +2

In light of the Higgs discovery and the nonobservation of sparticles at the LHC, we revisit the SUSY induced top quark flavor changing decay into the Higgs boson. We perform a scan…

hep-ph2022

Anomaly-free ALP from non-Abelian flavor symmetry

Chengcheng Han, M. L. López-Ibáñez, Aurora Melis +2

Motivated by the Xenon1T excess in electron-recoil measurements, we investigate the prospects of probing axion-like particles (ALP) in lepton flavor violation experiments. In parti…

hep-ph2014

A light SUSY dark matter after CDMS-II, LUX and LHC Higgs data

Junjie Cao, Chengcheng Han, Lei Wu +2

In SUSY, a light dark matter is usually accompanied by light scalars to achieve the correct relic density, which opens new decay channels of the SM like Higgs boson. Under current…

cs.AI2025

Introducing LongCat-Flash-Thinking: A Technical Report

Meituan LongCat Team, Anchun Gui, Bei Li +122

We present LongCat-Flash-Thinking, an efficient 560-billion-parameter open-source Mixture-of-Experts (MoE) reasoning model. Its advanced capabilities are cultivated through a metic…

hep-ph2025

Topological defects as effective dynamical dark energy

Haipeng An, Chengcheng Han, Borui Zhang

In this work, we consider the possibility that the dynamical dark energy hinted at by recent DESI data may be mimicked by the effects of additional components in the universe, pote…

hep-ph2018

Muon and Dark Matter in the MSSM

Peter Cox, Chengcheng Han, Tsutomu T. Yanagida

We investigate the possibility that both dark matter and the long-standing discrepancy in the anomalous magnetic moment of the muon may be explained within the MSSM. In light of th…

hep-ph2026

Cosmological Collider Signatures from Right-Handed Neutrino Loop

Jingtao You, Linghao Song, Chengcheng Han +3

We study cosmological collider (CC) signatures generated by right-handed neutrino loops in the setup of inflation combined with the neutrino seesaw mechanism. We formulate the infl…

hep-ph2012

Probing topcolor-assisted technicolor from top charge asymmetry and triple-top production at the LHC

Chengcheng Han, Ning Liu, Lei Wu +1

In a topcolor-assisted technicolor model (TC2) with large FCNC top quark couplings, we study its correlated contributions to the top quark forward-backward asymmetry () at…

hep-ph2022

The physics case of a 3 TeV muon collider stage

Jorge De Blas, Dario Buttazzo, Rodolfo Capdevilla +131

In the path towards a muon collider with center of mass energy of 10 TeV or more, a stage at 3 TeV emerges as an appealing option. Reviewing the physics potential of such muon coll…

hep-ph2018

LHC Search for Right-handed Neutrinos in Models

Peter Cox, Chengcheng Han, Tsutomu T. Yanagida

We consider right-handed neutrino pair production in generic models. We propose a new, model-independent analysis using final states containing a pair of same-sign muons…

cs.CL2024

Make Prompt-based Black-Box Tuning Colorful: Boosting Model Generalization from Three Orthogonal Perspectives

Qiushi Sun, Chengcheng Han, Nuo Chen +4

Large language models (LLMs) have shown increasing power on various natural language processing (NLP) tasks. However, tuning these models for downstream tasks usually needs exorbit…

hep-ph2013

Current experimental bounds on stop mass in natural SUSY

Chengcheng Han, Ken-ichi Hikasa, Lei Wu +2

Motivated by the recent progress of direct search for the productions of stop pair and sbottom pair at the LHC, we examine the constraints of the search results on the stop ($\tild…

cs.PL2021

Programming Knowledge Tracing: A Comprehensive Dataset and A New Model

Renyu Zhu, Dongxiang Zhang, Chengcheng Han +4

In this paper, we study knowledge tracing in the domain of programming education and make two important contributions. First, we harvest and publish so far the most comprehensive d…

hep-ph2021

Probing the doubly-charged Higgs with Muonium to Antimuonium Conversion Experiment

Chengcheng Han, Da Huang, Jian Tang +1

The spontaneous muonium-to-antimuonium conversion is one of the interesting charged lepton flavor violation processes. MACE is the next generation experiment to probe such a phenom…

cs.CL2023

Meta-Learning Siamese Network for Few-Shot Text Classification

Chengcheng Han, Yuhe Wang, Yingnan Fu +4

Few-shot learning has been used to tackle the problem of label scarcity in text classification, of which meta-learning based methods have shown to be effective, such as the prototy…

hep-ph2026

Line-of-sight magnetic-field propagation effects on axion-like particle constraints from GRB 221009A

Chengcheng Han, Zhanhong Lei, Jiajie Yang +1

High-energy photons from GRB 221009A provide a powerful opportunity to probe axion-like particles (ALPs) through photon-ALP oscillations in cosmic magnetic fields. We revisit the A…

hep-ph2021

Searching for heavy neutrino in terms of tau lepton at future hadron collider

Chengcheng Han, Tong Li, Chang-Yuan Yao

The tau lepton plays important role in the correlation between the low-energy neutrino oscillation data and the lepton flavor structure in heavy neutrino decay. We investigate the…

cs.CL2024

Learning to Check: Unleashing Potentials for Self-Correction in Large Language Models

Che Zhang, Zhenyang Xiao, Chengcheng Han +2

Self-correction has achieved impressive results in enhancing the style and security of the generated output from large language models (LLMs). However, recent studies suggest that…

hep-ph2015

(1) GeV dark matter in SUSY and a very light pseudoscalar at the LHC

Chengcheng Han, Doyoun Kim, Shoaib Munir +1

We analyze the prospects of the detection of a GeV neutralino dark matter, , in the Next-to-Minimal Supersymmetric Standard Model at the 14 TeV…

astro-ph.CO2025

Superhorizon fluctuations and the cosmic dipole problem

Ge Chen, Chengcheng Han, Linwei Qiu

Recent observations have identified a significant 4.9 tension between the cosmic dipole inferred from galaxy number counts and that derived from the Cosmic Microwave Background…

cs.SE2025

A Survey of Neural Code Intelligence: Paradigms, Advances and Beyond

Qiushi Sun, Zhirui Chen, Fangzhi Xu +15

Neural Code Intelligence -- leveraging deep learning to understand, generate, and optimize code -- holds immense potential for transformative impacts on the whole society. Bridging…

hep-ph2016

Implications of the 750 GeV Diphoton Excess in Gaugino Mediation

Chengcheng Han, Tsutomu T. Yanagida, Norimi Yokozaki

The 750 GeV diphoton excess reported by ATLAS and CMS indicates the presence of several pairs of the vector-like matter multiplets around TeV scale. If that is the case, radiative…

hep-ph2016

Apparent unitarity violation in top quark's mass off-shell region from a new physics at high energy colliders

Chengcheng Han, Mihoko M. Nojiri, Myeonghun Park

Perturbative unitarity conditions have been playing an important role by estimating the energy scale of new physics, including the Higgs mass as one of the most important examples.…

cs.CV2025

MARS2 2025 Challenge on Multimodal Reasoning: Datasets, Methods, Results, Discussion, and Outlook

Peng Xu, Shengwu Xiong, Jiajun Zhang +125

This paper reviews the MARS2 2025 Challenge on Multimodal Reasoning. We aim to bring together different approaches in multimodal machine learning and LLMs via a large benchmark. We…

hep-ph2012

Probing natural SUSY from stop pair production at the LHC

Junjie Cao, Chengcheng Han, Lei Wu +2

We consider the natural supersymmetry scenario in the framework of the R-parity conserving minimal supersymmetric standard model (called natural MSSM) and examine the observability…

hep-ph2017

Status of CMSSM in light of current LHC Run-2 and LUX data

Chengcheng Han, Ken-ichi Hikasa, Lei Wu +2

Motivated by the latest results of the LHC Run-2 and LUX experiments, we examine the status of the constrained minimal supersymmetric standard model (CMSSM) by performing a global…

hep-ph2021

Probing bino NLSP at lepton colliders

Junmou Chen, Chengcheng Han, Jin Min Yang +1

We consider a scenario where light bino is the next-to-lightest supersymmetric particle (NLSP) and gravitino/axino is the lightest superysmmetric particle (LSP). For a bino mass le…

hep-ph2014

Higgs pair production with SUSY QCD correction: revisited under current experimental constraints

Chengcheng Han, Xuanting Ji, Lei Wu +2

We consider the current experimental constraints on the parameter space of the MSSM and NMSSM. Then in the allowed parameter space we examine the Higgs pair production at the 14 Te…

cs.AI2026

LongCat-Flash-Thinking-2601 Technical Report

Meituan LongCat Team, Anchun Gui, Bei Li +162

We introduce LongCat-Flash-Thinking-2601, a 560-billion-parameter open-source Mixture-of-Experts (MoE) reasoning model with superior agentic reasoning capability. LongCat-Flash-Thi…

hep-ph2025

Cosmological Non-Gaussianity from Neutrino Seesaw Mechanism

Jingtao You, Linghao Song, Hong-Jian He +1

The neutrino mass generation via conventional seesaw mechanism is realized at high scales around GeV with natural Yukawa couplings of , making the test of neutrin…

hep-ph2018

Right-handed Neutrino Dark Matter in a U(1) Extension of the Standard Model

Peter Cox, Chengcheng Han, Tsutomu T. Yanagida

We consider minimal extensions of the Standard Model in which one of the right-handed neutrinos is charged under the new gauge symmetry and plays the role of dark matter. In…

hep-ph2018

A minimal extension of MSSM in light of the B decay anomaly

Guang Hua Duan, Xiang Fan, Mariana Frank +2

Motivated by the and anomalies from B decays, we extend the minimal supersymmetric model with a non-universal anomaly-free gauge symmetry, coupling no…

hep-ph2023

Correlation length of the angular mode for an approximate symmetry during inflation

Chengcheng Han

It is known that a light scalar field obtains fluctuations in the de Sitter inflationary background. Such fluctuations could provide an initial condition for baryogenesis through t…

hep-ph2024

Affleck-Dine Dirac Leptogenesis

Neil D. Barrie, Chengcheng Han

We present a minimal framework that realises successful Dirac Leptogenesis through the Affleck-Dine mechanism. A single right-handed neutrino and a neutrinophillic Higgs doublet ar…

hep-ph2015

Trail of the Higgs in the primordial spectrum

Jinn-Ouk Gong, Chengcheng Han, Shi Pi

We study the effects of the Higgs directly coupled to the inflaton on the primordial power spectrum. The quadratic coupling between the Higgs and the inflaton stabilizes the Higgs…

hep-ph2017

Flavoured Local Symmetry and Anomalous Rare Decays

Rodrigo Alonso, Peter Cox, Chengcheng Han +1

We consider a flavoured gauge symmetry under which only the third generation fermions are charged. Such a symmetry can survive at low energies (~TeV) while still allowing for…

hep-ph2016

Interpreting the 750 GeV diphoton excess by the singlet extension of the Manohar-Wise Model

Junjie Cao, Chengcheng Han, Liangliang Shang +3

The evidence of a new scalar particle from the 750 GeV diphoton excess, and the absence of any other signal of new physics at the LHC so far suggest the existence of new colore…

hep-ph2014

Constraining Top partner and Naturalness at the LHC and TLEP

Chengcheng Han, Archil Kobakhidze, Ning Liu +2

We investigate indirect constraints on the top partner within the minimal fermionic top partner model. By performing a global fit of the latest Higgs data, measu…

cs.LG2026

DORA: A Scalable Asynchronous Reinforcement Learning System for Language Model Training

Tianhao Hu, Xiangcheng Liu, Youshao Xiao +21

Reinforcement learning (RL) has become a critical paradigm for LLM post-training, yet the rollout phase -- accounting for 50--80% of total step time -- is bottlenecked by skewed ge…

hep-ph2014

Probing Light Higgsinos in Natural SUSY from Monojet Signals at the LHC

Chengcheng Han, Archil Kobakhidze, Ning Liu +3

We investigate a strategy to search for light, nearly degenerate higgsinos within the natural MSSM at the LHC. We demonstrate that the higgsino mass range in GeV, wh…

hep-ph2023

Freeze-in bino dark matter in high scale supersymmetry

Chengcheng Han, Peiwen Wu, Jin Min Yang +1

We explore a scenario of high scale supersymmetry where all supersymmetric particles except gauginos stay at a high energy scale which is much larger than the reheat…

hep-ph2019

Gaugino Mediation Scenarios for Muon and Dark Matter

Peter Cox, Chengcheng Han, Tsutomu T. Yanagida +1

We explore the possibility that the muon anomaly and the nature of dark matter can be simultaneously explained within the framework of gaugino mediation, focusing on bino-lik…

cs.AI2024

OS-Copilot: Towards Generalist Computer Agents with Self-Improvement

Zhiyong Wu, Chengcheng Han, Zichen Ding +5

Autonomous interaction with the computer has been a longstanding challenge with great potential, and the recent proliferation of large language models (LLMs) has markedly accelerat…

hep-ph2026

Right-Handed Neutrino Production by an Axion-like Inflaton: Implications for Leptogenesis

Weiyi Deng, Chengcheng Han, Wuzhou Yin +1

The paper analyzes how a derivative coupling between an axion‑like inflaton and heavy right‑handed neutrinos generates these particles during inflation and preheating, and evaluate…

#inflation#right-handed neutrinos#leptogenesis#axion-like particles
cs.CL2023

Meta-Learning Triplet Network with Adaptive Margins for Few-Shot Named Entity Recognition

Chengcheng Han, Renyu Zhu, Jun Kuang +5

Meta-learning methods have been widely used in few-shot named entity recognition (NER), especially prototype-based methods. However, the Other(O) class is difficult to be represent…

hep-ph2014

Probing light bino and higgsinos at the LHC

Chengcheng Han

Motivated by the naturalness, we study a simplified MSSM scenario where only the bino-like LSP and higgsino-like NLSP are light. We first scan the parameter space of this scenario,…

cs.CL2025

LongCat-Flash Technical Report

Meituan LongCat Team, Bayan, Bei Li +179

We introduce LongCat-Flash, a 560-billion-parameter Mixture-of-Experts (MoE) language model designed for both computational efficiency and advanced agentic capabilities. Stemming f…

cs.AI2025

RMoA: Optimizing Mixture-of-Agents through Diversity Maximization and Residual Compensation

Zhentao Xie, Chengcheng Han, Jinxin Shi +4

Although multi-agent systems based on large language models show strong capabilities on multiple tasks, they are still limited by high computational overhead, information loss, and…

hep-ph2019

Higgsino Dark Matter in a Non-Standard History of the Universe

Chengcheng Han

A light higgsino is strongly favored by the naturalness, while as a dark matter candidate it is usually under-abundant. We consider the higgsino production in a non-standard histor…

hep-ph2017

Anomaly-free local horizontal symmetry and anomaly-full rare B-decays

Rodrigo Alonso, Peter Cox, Chengcheng Han +1

The largest global symmetry that can be made local in the Standard Model + 3 while being compatible with Pati-Salam unification is . The gauge boson…

cs.CL2022

SpanProto: A Two-stage Span-based Prototypical Network for Few-shot Named Entity Recognition

Jianing Wang, Chengcheng Han, Chengyu Wang +5

Few-shot Named Entity Recognition (NER) aims to identify named entities with very little annotated data. Previous methods solve this problem based on token-wise classification, whi…

hep-ph2018

Searching for the light Higgsinos in MSSM at the future e-p colliders

Chengcheng Han, Ruibo Li, Ren-Qi Pan +1

The search of the light Higgsino {in the Minimal Supersymmetric Standard Model (MSSM)} is a crucial test for the criteria of the naturalness in supersymmetry. On the other hand, th…

hep-ph2014

SUSY effects in Higgs productions at high energy colliders

Junjie Cao, Chengcheng Han, Jie Ren +3

Considering the constraints from collider experiments and dark matter detections, we investigate the SUSY effects in the Higgs productions at an collider w…

hep-ph2020

A Complete Solution to the Strong CP Problem: a SUSY Extension of the Nelson-Barr Model

Jason Evans, Chengcheng Han, Tsutomu T. Yanagida +1

We present a supersymmetric solution to the strong CP problem based on spontaneous CP violation which simultaneously addresses the affects coming from supersymmetry breaking. The g…

hep-ph2017

Top-squark in natural SUSY under current LHC run-2 data

Chengcheng Han, Jie Ren, Lei Wu +2

We utilize the recent LHC-13 TeV data to study the lower mass bound on top-squark (stop) in natural supersymmetry. We recast the LHC sparticle inclusive search of $(\ge 1){\rm jets…

hep-ph2013

A light Higgs scalar in the NMSSM confronted with the latest LHC Higgs data

Junjie Cao, Fangfang Ding, Chengcheng Han +2

In the Next-to-Minimal Supersymemtric Standard Model (NMSSM), one of the neutral Higgs scalars (CP-even or CP-odd) may be lighter than half of the SM-like Higgs boson. In this case…