基于迭代组元减除的堆积与本底事件缓解

Jet areas as a tool for background subtraction

In all modern hadronic colliders, jets recieve a large contribution from a soft background: pileup in the case of proton-proton collisions at the LHC, or the underlying event for heavy-ion collisions at RHIC or the LHC. In these proceedings, we present a generic and simple method, based on jet areas, to subtract the contribution of the soft background from the jets. This allows for more precise kinematic reconstruction of jets in dense environments.

Boosting the Standard Model Higgs Signal with the Template Overlap Method

We show that the Template Overlap Method can improve the signal to background ratio of boosted $H\to b \bar b$ events produced in association with a leptonically decaying $W$. We introduce several improvements on the previous formulations of the template method. Varying three-particle template subcones increases the rejection power against the backgrounds, while sequential template generation ensures an efficient coverage in template phase space. We integrate b-tagging information into the template overlap framework and introduce a new template based observable, the template stretch. Our analy…

Medium Recoils and background subtraction in JEWEL

\textsc{Jewel} is a fully dynamical event generator for jet evolution in a dense QCD medium, which has been validated for multiple jet and jet-like observables. Jet constituents (partons) undergo collisions with thermal partons from the medium, leading to both elastic and radiative energy loss. The recoiling medium scattering centers carry away energy and momentum from the jet. Keeping track of these recoils is essential for the description of intra-jet observables. Since the thermal component of the recoils is part of the soft background activity, comparison with data on jet observables requi…

重离子碰撞中淬火喷注的模型无关标记

Model-Agnostic Tagging of Quenched Jets in Heavy-Ion Collisions

针对重离子碰撞中淬火喷注识别需考虑多种实验效应的挑战，提出整合喷注组分表示与全局可观测量的可解释序列注意力机器学习框架，为模型无关的淬火喷注标记建立新基准。

深度学习在QGP背景下的喷注修改

Deep learning for jet modification in the presence of the QGP background

本研究利用深度学习方法预测喷注在QGP介质中的分数能量损失，发现DGCNNs在背景去除后能保持高精度，优于CNNs。

The Hidden Geometry of Particle Collisions

We establish that many fundamental concepts and techniques in quantum field theory and collider physics can be naturally understood and unified through a simple new geometric language. The idea is to equip the space of collider events with a metric, from which other geometric objects can be rigorously defined. Our analysis is based on the energy mover's distance, which quantifies the "work" required to rearrange one event into another. This metric, which operates purely at the level of observable energy flow information, allows for a clarified definition of infrared and collinear safety and re…

A background estimator for jet studies in p+p and A+A collisions

Experimentally, jet physics studies face an unavoidable task: distinguishing, at the detector level, the particles produced in the hard partonic scattering from the ones created in unrelated soft processes such as pileup interactions in high-luminosity proton-proton scattering or the underlying event in heavy-ion collisions. The fluctuating nature of the background constitutes the main source of uncertainty for any subtraction algorithm. Aiming at mitigating the effect of such fluctuations, we present a new method to estimate the background contribution to the transverse momentum on a jet-by-j…

探测相对论重离子碰撞中通过喷注子结构观测量实现的喷注-介质相互作用

Probing jet-medium interactions via jet substructure observables in relativistic heavy-ion collisions

本研究利用多相输运模型，通过Soft Drop算法重构喷注子结构观测量，发现中心PbPb碰撞中高$M_g/p_T$区域增强源于喷注-介质相互作用，且该效应与大角度散射相关。