APCTP Workshop on Precision Calculation and Collider Phenomenology

3 Nov 2024, 09:00 → 5 Nov 2024, 21:00 Asia/Seoul

Seminar room (512) (Asia Pacific Center for Theoretical Physics (APCTP))

As the Large Hadron Collider (LHC) is gearing up for its high-luminosity phase, theoretical community will need to keep up with the accuracy of the current and upcoming experimental data, in order to make the most out of the LHC data. Theoretical predictions will have to be computed at the highest possible accuracy and innovative approaches should be employed to extract as many insight as possible from the LHC data.

This workshop aims to bring together experts in precision calculation and collider phenomenology in the Asia-Pacific region. Topics covered in this workshop, among others are:

• High-precision theoretical predictions for Standard Model and Beyond the Standard model processes
• Application of machine learning to collider phenomenology
• Precision observables for LHC phenomenology
• Beyond the Standard Model Phenomenology
• Feynman integrals and special functions for scattering amplitude

The workshop will be held at APCTP Headquarter in Pohang, South Korea.

Invited speakers:

• Souvik Bera (APCTP)
• Huan-Yu Bi (Peking University)
• Xuan Chen (Shandong University)
• Shilpa Jangid (APCTP)
• Adil Jueid (IBS)
• Chul Kim (SeoulTech)
• Soojin Lee (Konkuk University)
• Myeonghun Park (SeoulTech)
• Rene Poncelet (IFJ PAN Krakow)
• Narayan Rana (NISER Bhubaneswar)
• Minho Son (KAIST)

 

Please submit the title and abstract of your talk and indicate your arrival and departure date on the Registration page by September 30th, 2024.

Local organiser: Heribertus Bayu Hartanto (bayu.hartanto@apctp.org) 

The APCTP is supported by the Korean Government through the Science and Technology Promotion Fund and Lottery Fund and strives to maximize public value through its various activities.
아시아태평양이론물리센터는 정부의 과학기술진흥기금 및 복권기금 지원으로 공익적 가치 제고에 힘쓰고 있습니다.

Sunday 3 November

16:00 Arrival

18:30 Dinner

Monday 4 November

1 Energy correlators in the large N limit

Speaker: Chul Kim

2 One-point correlators of conserved and non-conserved charges in QCD

Theoretical and phenomenological aspects of the density matrix of one-point correlators will be discussed in the context of the states produced by a chiral current, as in the decay of a polarized electroweak boson.

Speaker: Minho Son

11:00 Coffee Break

3 Machine learning for Collider Physics

Speaker: Myeonghun Park

12:15 Lunch

4 Unveiling the Unexplored Decay Mode of a Light Charged Higgs Boson to an Off-Shell Top Quark and a Bottom Quark

We investigate the unexplored decay mode of a light charged Higgs boson (H±) into an off-shell top quark and a bottom quark (H± → t*b) in the type-I two-Higgs-doublet model. Focusing on the 130-170 GeV mass range, we propose pair production of charged Higgs bosons as a model-independent probe. Our comprehensive analysis at the HL-LHC and a 100 TeV pp collider reveals challenges due to soft b-jets. We then explore the potential of multi-TeV muon colliders, demonstrating that a 3 TeV muon collider with 1 ab^-1 luminosity can achieve discovery-level significance. This talk will present our methodology, results, and the comparative performance of different collider scenarios, highlighting the crucial role of muon colliders in exploring physics beyond the Standard Model.

Speaker: SooJin Lee

5 Boosting probes of CP violation in the top Yukawa coupling with Deep Learning

In this talk, I will discuss the CP properties of a Higgs boson coupling with a top quark pair, focusing on events where the Higgs state decays into a pair of $b$-quarks and the top-antitop system decays leptonically. The novelty of this analysis resides in the exploitation of two conditional Deep Learning (DL) networks: a Multi-Layer Perceptron (MLP) and a Graph Convolution Network (GCN). These models are trained for selected CPV phase values and then used to interpolate all possible values ranging from $0 \text{ to } \pi/2$. This enables a comprehensive assessment of sensitivity across all CP phase values, thereby streamlining the process as the models are trained only once. Notably, the conditional GCN exhibits superior performance over the conditional MLP, owing to the nature of graph-based Neural Network (NN) structures. Our Machine Learning (ML) informed findings indicate that assessment of the CP properties of the Higgs coupling to the $t\bar t$ pair can be within reach of the HL-LHC, quantitatively surpassing the sensitivity of more traditional approaches.

Speaker: Adil Jueid

15:30 Coffee Break

6 Phenomenological study of the electroweak vacuum in Beyond Standard Model Scenarios

The electroweak vacuum, mainly at zero temperature, is investigated as how the quantum fluctuations affect and constrain different beyond Standard Model (BSM) extensions The quantum fluctuations can lead to a second minimum of the potential, which can be a stable global minimum. The Standard Model falls within the possibility of metastability, which means there can be a deeper minimum. Various beyond-standard model scenarios get bounds from the possibilities of vacuum instability or metastability. It has been seen that the extension of the SM with a scalar in general gives more stability to the vacuum, but the scalar quartic couplings get strong bounds from the perturbative unitarity. Different contributions with non-trivial gauge representation can tamper the behaviour of the SM gauge couplings as well, which are also shown explicitly. The LHC phenomenology in these extended scenarios is also discussed.

Speaker: Shilpa Jangid

16:45 Free Discussions

18:30 Dinner

Tuesday 5 November

7 Recent development and phenomenological studies with NNLOJET

Speaker: Xuan Chen

8 High-precision prediction for multi-scale processes at the LHC

Comparisons of higher-order predictions within the Standard Model of Particle Physics (SM) to data are central to high-energy collider experiments like the Large Hadron Collider (LHC). Processes with multiple kinematic scales, such as multi-jet and prompt photon production, provide a unique possibility for probing Quantum Chromodynamics (QCD). These processes directly test perturbative QCD and can be used to extract fundamental parameters like the strong coupling constant and to search for BSM physics. Recent developments enabled lifting three-jet, photon plus two-jet, photon-pair plus jet, three-photon and other two-to-three cross-sections to QCD’s next-to-next-to-leading order (NNLO). In this talk, I will give an overview of the phenomenology for such processes and the calculational techniques used in their computation.

Speaker: Rene Poncelet

11:00 Coffee Break

9 Electroweak Corrections to Double Higgs Production at the LHC

We present the results for the complete next-to-leading order electroweak corrections to pp → HH at the Large Hadron Collider, focusing on the dominant gluon-gluon fusion process. While the corrections at the total cross-section level are approximately −4%, those near the energy of HH production threshold exceed +15%, and corrections at the high-energy region are around −10%, leading to a shape distortion for the differential distributions. Our findings substantially diminish the theoretical uncertainties associated with this pivotal process, providing valuable input for understanding the shape of the Higgs boson potential upon comparison with experimental measurements.

Speaker: Huan Yu Bi

12:15 Lunch

10 NNLO QCD corrections to semi-inclusive DIS

In this talk, we present the second order QCD corrections to the semi-inclusive deep-inelastic scattering process. We compute both virtual and phase-space integrals analytically, using the state-of-the-art techniques namely, the method of reverse unitarity, IBP reduction and the method of differential equations. After appropriate mass-subtraction, we obtain the finite partonic cross-section and perform a numerical analysis to demonstrate the impact of NNLO correction.

Speaker: Narayan Rana

11 Expansion of hypergeometric functions about their parameters

Speaker: Souvik Bera

15:30 Coffee Break

16:00 Free Discussions

18:30 Dinner