Higgs potential and BSM opportunity 希格斯物理研讨会

27 Aug 2021, 07:00 → 31 Aug 2021, 20:10 Asia/Shanghai

南京大学（鼓楼校区）线上会议 Nanjing University (Gulou Campus) at ZOOM

                   

 

       本次会议由江苏省物理学会和南京大学物理学院联合主办。由于疫情原因改为纯线上会议，远程会议信息如下：

• ZOOM 会议 ID:  816 8690 7874，密码：062256。直接点击链接：https://us02web.zoom.us/j/81686907874?pwd=c2pPL1hHdThMS3JxOCtKUnFYYkJkUT09
• 蔻享直播链接为：https://www.koushare.com/lives/room/567358

       希格斯粒子发现后，精确测量希格斯性质，深入理解电弱对称性破缺机制，以及寻找超出标准模型新物理是LHC与未来对撞机实验的重点。今年7-8月的夏季会议上，LHC实验将报道一批Run 2最新的物理研究结果，明年开始新的Run 3实验运行。因此，理解新的实验结果，规划未来的实验研究在此时显得尤为重要。

       本次会议旨在理解电弱对称性破缺机制，内容包含精确测量希格斯粒子性质、探测希格斯场自耦合以及寻找超出标准模型新物理等。会议将邀请国内外理论物理学家和实验物理学家共同探讨上述课题。

       邀请报告以及提交报告均已安排到了“Timetable”上，其中邀请报告时长为25+5'，提交报告时长为15+5'。如有问题，欢迎大家联系相关召集人。

     This workshop is co-organized by JiangSu Society of Physics and School of Physics at Nanjing University. Due to the Covid-19 outbreak, we switch to the online meeting. The remote meeting information are:

• ZOOM meeting ID:  816 8690 7874，password：062256 . Direct link：https://us02web.zoom.us/j/81686907874?pwd=c2pPL1hHdThMS3JxOCtKUnFYYkJkUT09
• Koushare live stream link:  https://www.koushare.com/lives/room/567358

 

  After the discovery of the Higgs boson, precise measurements of Higgs properties, understanding the dynamics of the Electro-Weak Symmetry Breaking and searching for the new physics Beyond the Standard Model are among the main physics targets for LHC and the future colliders.

    During this summer many new results will be updated with the full Run 2 data, and next year LHC will start the Run 3 data collection. It is crucial to understand new results and explore the opportunities at future experiments.

    This workshop will bring together theorists and experimenters to discuss about Higgs precise measurements, Higgs self-coupling studies, BSM physics searches and the opportunities at the LHC and beyond. 

     The schedule of the presentation is published in "Timetable".  The plenary talk is 25+5' and the submitted talk is 15+5'. If you have any problems, please contact the corresponding session conveners.

 

会议注册费：No registration fee. 

 

会务组负责人：金山、陈申见、刘佐伟、张雷、夏力钢、刘坤（上交）、孙小虎（北大）

地方会务组：张雷(leizhang1801@mail.nju.edu.cn, lei.zhang@cern.ch)、夏力钢(ligang.xia@cern.ch)、周思成 (zhousc@nju.edu.cn, 秘书)

Local organizers: Lei Zhang (leizhang1801@mail.nju.edu.cn, lei.zhang@cern.ch)、Ligang Xia (ligang.xia@cern.ch)、Sicheng Zhou (zhousc@nju.edu.cn, secretary)

 

会议组委会：(从北到南)

Organization committee: (From north to South) 

北大：曹庆宏，刘佳，孙小虎；清华：陈新；理论所：舒菁，于江浩；北航：袁丽；高能所：方亚泉，黄艳萍，陈明水，张岑；山大：马连良；科大：吴雨生；南大：张雷、刘佐伟；南京师大：武雷；上交：刘坤，Michael RM；华科：康召丰；复旦：顾嘉荫；浙大：肖朦；重庆大学：边立功；中山：张宏浩

PKU: Qinghong Cao, Jia Liu, Xiaohu Sun; THU: Xin Chen; ITP: Jing Shu, Jianghao Yu; BHU: Li Yuan; IHEP: Yaquan Fang, Yanping Huang, Mingshui Chen, Cen Zhang; SDU: Lianliang Ma; USTC: Yusheng Wu; NJU: Lei Zhang, Zuowei Liu; NNJU: Lei Wu; SJTU: Kun Liu, Michael Ramsey-Musolf; HUST: Kaofeng Kang; FDU: Jiayin Gu; ZJU: Meng Xiao; CQU: Ligong Bian; SYSU: Honghao Zhang

Friday, 27 August

08:00 → 18:00 Pre-School

Conveners: Kun LIU (Tsung-Dao Lee Institute, Shanghai Jiao Tong University) , 立功 边 (重庆大学)

09:00 School opening

09:20 Introduction to the standard model and electro-weak symmetry breaking

Speaker: Prof. 召丰 康 (华中科技大学)

Slides SM_Zhaofeng.pdf

13:00 Extension of standard model, e.g. 2HDM

Speaker: 宁 陈 (Nankai University)

Slides 2HDMtalk_Nanjing.pdf

15:30 Experimental Higgs physics, e.g. discovery, precise measurement, BSM Higgs searches

Speaker: Prof. Yanwen Liu (USTC)

Slides

• Lect1_NanjingAug272021LHCHiggs.pdf
• Lect1_NanjingAug272021LHCHiggs.pptx
• Lect2_NanjingAug272021LHCHiggs.pdf
• Lect2_NanjingAug272021LHCHiggs.pptx

Saturday, 28 August

08:40 → 09:10 Openning

Conveners: Prof. Shan Jin (ihep) , Prof. Shenjian Chen (Nanjing University) , Dr 雷(Lei) 张(Zhang) (南京大学(Nanjing University))

08:40 Openning

Slides 20210828_introduction.pdf

08:55 Welcome from NJU

Speaker: Prof. 伯根 王

09:10 → 19:00 Higgs precise measurement

Conveners: Dr Jiayin Gu (JGU Mainz) , Prof. Lilin Yang (Zhejiang University) , Prof. Mingshui CHEN (IHEP) , Yusheng Wu (University of Science and Technology of China)

09:10 Higgs Overview

Speaker: Liantao Wang (University of Chicago)

Slides HiggsBSM_NanJing.pdf

09:40 Precise theoretical predictions for Higgs processes

Speaker: Jian Wang (Shandong University)

Slides WangJian_talk_Nanjing

10:10 Precise Higgs measurements at LHC

Speaker: 楠 鲁 (California Institute of Technology)

Slides precise_Higgs_measurements_08262021_NanLu.pdf

10:40 Coffee break

11:00 Probing the electroweak symmetry breaking with Higgs production at the LHC

The electroweak symmetry breaking (EWSB) mechanism is still an undecided question in particle physics. We propose to utilize the single top quark and Higgs associated production ($th$), $Zh$ production via gluon fusion at the LHC to probe the couplings between the Higgs and the gauge bosons and further to test the EWSB. We demonstrate that the $th$ and $gg\to Zh$ productions are sensitive to the relative sign of couplings ($ht\bar{t}$, $hWW$) and ($ht\bar{t}$, $hZZ$), respectively. We find that the relative sign between $hWW$ and $hZZ$ couplings could be fully determined after combining the present measurements from $gg\to h$, $t\bar{t}h$ and the $th$, $Zh$ channels at the 13 TeV LHC, and this conclusion is not sensitive to the possible new physics contribution induced by $Zt\bar{t}$ couplings in the $gg\to Zh$ production.

Speaker: Dr Bin Yan (LANL)

Slides EWSB_BY.pdf

11:20 Measurement of the CP property of the Higgs to top Yukawa coupling

Speaker: 洪洮 杨 (Lawrence Berkeley National Laboratory)

Slides ttH_gamgam_CP_Hongtao_Yang.pdf

11:40 Next-to-leading order corrections for gg->ZH with top quark mass dependence

Recently, we present for the first time a calculation of the complete next-to-leading order corrections to the $gg \to ZH$ process. We use the method of small mass expansion to tackle the most challenging two-loop virtual amplitude, in which the top quark mass dependence is retained throughout the calculations. We show that our method provides reliable numeric results in all kinematic regions, and present phenomenological predictions for the total and differential cross sections at the Large Hadron Collider and its future upgrades. Our results are necessary ingredients towards reducing the theoretical uncertainties of the $pp \to ZH$ cross sections down to the percent-level, and provide important theoretical inputs for future precision experimental collider programs. In this talk, I will start with a brief introduction to the small mass expansion and then show our new results for the $ZH$ production at the LHC.

Speaker: 国兴 王 (Peking University)

Slides HH_ZH-Guoxing_Wang.pdf

12:00 Lunch break

14:00 Search for rare Higgs processes

Speaker: Dr yanping huang (ihep)

14:30 Measurements of Higgs boson production using decays to two c-quarks with the ATLAS detector

Testing the couplings of the Higgs boson to quarks is important to understand the origin of quark masses. The next most promising candidate is the decay to a pair of charm quark and antiquark. The presentation will focus on the analysis of the associated production of the Higgs boson with a W or Z boson performed by the ATLAS Collaboration using data collected between 2015 and 2018, and will describe the analysis strategy employed to search for the H→cc signal. As a result, the best limit set on Higgs to charm quark Yukawa coupling modifier (κC) to date will be shown.

Speaker: Mr Tao Wang (USTC)

Slides Measurements_of_Higgs_boson_production_using_decays_to_two_c-quarks_with_the_ATLAS_detector_presentation.pdf

14:50 Fiducial and differential cross-section measurements in the di-photon channel using full Run2 dataset at ATLAS

Since the discovery of a scalar particle with mass at 125 GeV in the experiments ATLAS and CMS at LHC, different measurements based on its properties have been performed and the observations nicely correspond to the Higgs boson predicted by the Standard Model of particle physics. Among these measurements, the fiducial and differential cross-section play an important role in the test of the SM predictions as well as in the probe for BSM physics contributions exploring a variety of physics observables. Given that these measurements are performed in a specific region of the phase space (fiducial region), the model dependence is reduced. In this talk, the latest results on the differential and fiducial cross-section of the Higgs boson decay in the di-photon channel with full Run2 dataset (139 fb-1) collected with ATLAS experiment will be discussed.

Speaker: Fábio Alves (Nanjing University)

Slides HiggsWorkshop_August282021.pdf

15:10 Combined measurements of Higgs boson production and decay and constraints on the Higgs boson self-coupling from the combination of single-Higgs and double-Higgs production analyses performed with the ATLAS experiment

A combination of measurements of Higgs boson production cross sections and branching fractions is presented. The combination is based on the analyses of the Higgs boson decay modes H->yy, ZZ*, WW*, tautau, bb, mumu, and searches for decays into invisible final states. Up to 139 fb-1 of pp collision data collected at sqrt(s)=13 TeV with the ATLAS detector are used. Combined cross section measurements are presented for the ggF, VBF, WH, ZH and ttH. The global signal strength, defined as the measured Higgs boson signal yield normalized to its SM prediction, is determined to be mu=1.06+/-0.07. The combined measurement yields an observed (expected) significance for the WH of 6.3sigma (5.2sigma). Measurements in kinematic regions defined within the simplified template cross section framework are also shown. The results are interpreted in terms of modifiers applied to the Standard Model couplings of the Higgs boson to other particles. No significant deviations from SM predictions are observed. Constraints on the Higgs boson self-coupling are set by combining the single Higgs boson analyses targeting the yy, ZZ*, WW*, tautau and bb decay channels and the double Higgs boson analyses in the bbbb, bbtautau and bbyy decay channels. The data used in these analyses correspond to an integrated luminosity of up to 79.8 fb-1 for single Higgs boson analyses and up to 36.1 fb-1 for the double Higgs boson analyses. With the assumption that new physics affects only the Higgs boson self-coupling (lambda_HHH), values outside the interval [-2.3, 10.3] are excluded at 95% CL. Results with less stringent assumptions are also provided, introducing additional coupling modifiers for the Higgs boson interactions with the other SM particles.

Speaker: Kunlin RAN (Beijing)

Slides kunlinRan_comb_20200828.pdf

15:30 Coffee break

15:50 Measurements of Higgs boson decaying into tau leptons using 139 ifb at the ATLAS experiment

The most recent results for the cross-section measurements of the Higgs boson decaying into tau leptons at the ATLAS experiment will be presented. These results are setting the base for other searches in the Higgs boson sector in the tau final state aiming to look for physics beyond the Standard Model. The analysis is performed using the 139 ifb dataset recorded by the ATLAS experiment at LHC in the period 2015-2018. A description of the analysis strategy concerning the signal categorization as well as the background estimation will be given, followed by an overview and discussion of the main analysis results : the inclusive Higgs boson to tau cross-section, the cross-section measurement for each of the main Higgs boson production mode at the LHC and the measurements within the Simplified Template Cross Section (STXS).

Speaker: Antonio De Maria (Nanjing University)

Slides Slides_Htt__NJU_workshop_2021_ADM.pdf

16:10 All order nonfactorizable jet veto effects in Higgs boson production

I will discuss nonfactorizable QCD corrections from central jet veto to Higgs boson production at the Large Hadron Collider. At hadron colliders, phase factors in the scattering amplitudes lead to double-logarithmic corrections starting at four-loop order. I will introduce our recent work on the first all-order structure of these “super-leading” logarithms. Our analysis shows that in certain kinematic distributions the nonfactorizable corrections can be as large as a percent making them quite comparable to their factorizable counterparts.

Speaker: Prof. Dingyu Shao (Fudan University)

Slides Higgs_Najing_DYShao.pdf

16:30 Probe BSM physics with the interaction between the Higgs boson and top quark

The top quark is the heaviest elementary particle, studying its interaction with the Higgs boson not only helps to further understand the newly discovered Higgs boson itself, but also opens new opportunities to probe the BSM physics. This talk will summarize recent new experimental results that connect the top-Higgs interaction with searches of new physics beyond the standard model with the LHC Run 2 dataset.

Speaker: Hualin Mei (U)

Slides 20210828_higgspotential_bsm_conference.pdf https://docs.google.com/presentation/d/11X_BcymKVLMbQ2CNIK8nBdR9H0_bLF6dHU3v9hCm5i0/edit?usp=sharing

16:50 Physics Highlights at CEPC

Speaker: Mr Manqi Ruan (IHEP)

Slides CEPC_Higgs_&_BSM_-_Nanjing.pdf

Sunday, 29 August

09:00 → 18:00 Di-Higgs/Scalar

Conveners: Prof. Fapeng Huang (中山大学) , Jianghao Yu (University of Massachusetts Amherst) , Prof. Xiaohu SUN (Peking University) , Prof. Yaquan FANG Yaquan (高能所)

09:00 Composite Higgs and Dark Matter

Speaker: Mr Chengfeng Cai (Sun Yat-Sen University)

Slides CH_and_DM.pdf

09:30 Higgs potential and phase transition

Speakers: Huaike Guo (Institute of Theoretical Physics) , Prof. Jing Shu (ITP)

Slides Huaike.pdf

10:00 Primordial black holes from a cosmic phase transition: The collapse of Fermi-balls

We propose a novel primordial black hole (PBH) formation mechanism based on a first-order phase transition (FOPT). If a fermion species gains a huge mass in the true vacuum, the corresponding particles get trapped in the false vacuum as they do not have sufficient energy to penetrate the bubble wall. After the FOPT, the fermions are compressed into the false vacuum remnants to form non-topological solitons called Fermi-balls, and then collapse to PBHs due to the Yukawa attractive force. We derive the PBH mass and abundance, showing that for a $\mathcal{O}({\rm GeV})$ FOPT the PBHs could be $\sim10^{17}$ g and explain all of dark matter. If the FOPT happens at higher scale, PBHs are typically overproduced and extra dilution mechanism is necessary to satisfy current constraints.

Speaker: 柯盼 谢 (Seoul National University)

Slides HIggs_Nanjing_online.pdf

10:20 Effective picture of cosmic bubble expansion

We derive an effective equation-of-motion for an expanding bubble wall in the thermal plasma with a general form of the thermal friction. The efficiency factor for gravitational waves productions from colliding bubble walls is obtained with a special interest for the strong first-order phase transition. Primary authors Prof. Rong-Gen Cai (ITP-CAS)， Shao-Jiang Wang

Speaker: Mr Shao-Jiang Wang (ITP)

Slides Nanjing2021(Shao-Jiang_Wang).pdf

10:40 Coffee break

11:00 电弱相变中引力波信号的精确计算

The energy budget of electroweak first-order phase transition is essential for the gravitational wave spectra. Most of the previous studies are based on the bag model with same sound velocity in the symmetric and broken phase. We study the energy budget and the corresponding gravitational wave spectra beyond the bag model, where the sound velocities could be different in the symmetric and broken phase. Taking the Higgs sextic effective model as a representative model, we calculate the sound velocities in different phase, the gravitational wave spectra and the signal-to-noise ratio for different combinations of phase transition parameters beyond the bag model. We compare these new results with the ones obtained from the bag model. The proper sound velocities and phase transition parameters at the appropriate temperature are important to obtain more precise predictions.

Speaker: Dr 潇 王 (中山大学天琴中心)

Slides Precise_calculation_of_gravitational_wave_in_electroweak_phase_transition.pdf

11:20 Probing the B+L violation process with the observation of cosmic magnetic field

We numerically investigate the B+L violation process by performing three-dimensional lattice simulations of a unified scenario of first-order phase transitions and the sphaleron generation. The simulation results indicate that the Chern-Simons number changes along with the helical magnetic field production when the sphaleron decay occurs. Based on these numerical results, we then propose a novel method to probe the baryon asymmetry generation of the Universe, which is a general consequence of the electroweak sphaleron process, through the astronomical observation of corresponding helical magnetic fields.

Speaker: Prof. Ligong Bian (Chongqing University)

Slides PMFCS_FOPT_Dihiggs21.pdf

11:40 Probing electroweak phase transition with multi-TeV muon colliders and gravitational waves

We study the complementarity of the proposed multi-TeV muon colliders and the near-future gravitational wave (GW) detectors to the first order electroweak phase transition (FOEWPT), taking the real scalar extended Standard Model as the representative model. A detailed collider simulation shows the FOEWPT parameter space can be greatly probed via the the vector boson fusion production of the singlet, and its subsequent decay to the di-Higgs or di-boson channels. Especially, almost all the parameter space yielding detectable GW signals can be probed by the muon colliders. Therefore, if we could detect stochastic GWs in the future, a muon collider could provide a hopeful crosscheck to identify their origin. On the other hand, there is considerable parameter space that escapes GW detections but is within the reach of the muon colliders. The precision measurements of Higgs couplings could also probe the FOEWPT parameter space efficiently.

Speaker: Dr Wei Liu (Nanjing University of Science and Technology)

Slides talk-mc-Weiliu_long.pdf

12:00 Lunch time

14:00 Non-resonant di-Higgs process at LHC

Speaker: Luca Cadamuro

Slides HH_nonresonant_overview.pdf

14:30 Search for Higgs boson pair production in 𝑏𝑏𝛾𝛾 final state

Searches are performed for non-resonant and resonant di-Higgs boson production in the 𝑏𝑏 ̄𝛾𝛾 final state. The data set used corresponds to an integrated luminosity of 139 fb−1 of proton–proton collisions at a center-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. No excess with respect to background expectations is found and upper limits on the di-Higgs boson production cross sections are set. A 95% confidence level upper limit of 130 fb is set on the 𝑝𝑝 → 𝐻𝐻 non-resonant production, where the expected limit is 180 fb. The observed (expected) limit corresponds to 4.1 (5.5) times the cross section predicted by the Standard Model. The observed (expected) limit on the Higgs boson trilinear coupling modifier 𝜅𝜆 is extracted to be [-1.5, 6.7] ([-2.4, 7.7]) at 95% confidence level. The constraints on 𝜅𝜆 are obtained over an expected background hypothesis excluding 𝑝𝑝 → 𝐻𝐻 production. For the resonant production of a new hypothetical scalar particle 𝑋 (𝑋 → 𝐻𝐻 → 𝑏𝑏 ̄𝛾𝛾), limits on the cross section 𝑝𝑝 → 𝑋 → 𝐻𝐻 are presented for the narrow-width approximation as a function of 𝑚𝑋 in the range 251 GeV ≤ 𝑚𝑋 ≤ 1000 GeV. The observed (expected) limits on the cross section 𝑝𝑝 → 𝑋 → 𝐻𝐻 range from 610 fb to 47 fb (360–43 fb) over the considered mass range.

Speaker: 子航 贾 (Nanjing University)

Slides Zihang_HHyybb_0829.pdf

14:50 Search for Higgs boson pair production in the bbττ decay channel using 13 TeV pp collision data from the ATLAS detector

A search for non-resonant and resonant Higgs boson pair production in bbττ final states is conducted using p-p collision data with an integrated luminosity of 139 fb−1 collected at s=√13 TeV by the ATLAS detector at the LHC. Events with at least one τ-lepton decaying hadronically are considered. Multivariate analysis techniques are used to extract the signals. The talk will show an overview of the physics motivation, the analysis methodology as well as the preliminary results.

Speaker: 博文 张 (Nanjing University)

Slides HH_bbtautau_Nanjing.pdf

15:10 Measuring Higgs Boson Self-couplings with 2→3 VBS Processes

We study the measurement of Higgs boson self-couplings through 2 → 3 vector boson scattering (VBS) processes in the framework of Standard Model effective field theory (SMEFT) at both proton and lepton colliders. The SMEFT contribution to the amplitude of the 2 → 3 VBS processes, taking WLWL → WLWLh and WLWL → hhh as examples, exhibits enhancement with the energy A(BSM)/A(SM) ~which indicates the sensitivity of these processes to the related dimension-six operators in SMEFT. Simulation of the full processes at both hadron and lepton colliders with a variety of collision energies are performed to estimate the allowed region on and . Especially we find that, with the help of exclusively choosing longitudinal polarizations in the final states and suitable cuts, WWh process is as important as the more widely studied triple Higgs production (hhh) in the measurement of Higgs self-couplings. Our analysis indicates that these processes can play important roles in the measurement of Higgs self-couplings at future 100 TeV pp colliders and muon colliders. However, their cross sections are generally tiny at low energy machines, which makes them much more challenging to explore.

Speaker: Dr Junmou （俊谋） Chen （谌） (KIAS)

Slides 2to3-VBS-short.pdf

15:30 Coffee break

15:50 BSM resonance search for HH (SH, SS) at LHC

Speaker: Bruce Mellado

Slides NANJING_2HDMS_280821.ppt

16:20 The multilepton anomalies at the LHC and the prospect of new physics at the EW scale

A study showed that the multilepton anomalies in the LHC data could be explained by adding two real scalar bosons to the SM. This study provides a more comprehensive set of LHC results of the multilepton production. We find that combining such results leads to substantial inconsistencies between the data and SM Monte Carlo predictions. These discrepancies appear in corners of the phase-space where different SM processes dominate, indicating that the potential miss modelling of a single SM process is unlikely to explain these excesses.

Speaker: ABDUALAZEM FADOL MOHAMMED EBRHIM (高能所)

Slides Multilepton.pdf

16:40 Probing Higgs boson properties with boosted objects at the CMS experiment

Advances in boosted jet tagging techniques, particularly with novel machine learning approaches, have led to significant performance improvements in the reconstruction and identification of the hadronic decays of the Higgs boson and provided additional handles to probe the Higgs boson properties at the LHC. In this talk, I will present recent progress in machine learning-based methods for boosted Higgs boson reconstruction and discuss their applications in recent CMS searches, e.g., the H->cc decay and the VBF Higgs pair production.

Speaker: Huilin Qu (CERN)

Slides Higgs_Boosted_H_Qu.pdf

17:00 New Physics bounded from above: 2HDM confronting strong 1st order electroweak phase transition

I will discuss the general difficulty in New Physics search, and how to put an upper limit on New Physics scale (which can be detected or excluded in the near future) via strong 1st order electroweak phase transition.

Speaker: mengchao Zhang (itp)

Slides NJU_2021_mczhang.pdf

Monday, 30 August

09:00 → 18:00 BSM Higgs sector

Conveners: Jian Wang (Shandong University) , Dr Lei Wu (Nanjing Normal University) , Li Yuan (Beihang University) , 数(Shu) 李(Li) (TDLI, SJTU)

09:00 BSM Higgs couplings

Speaker: Prof. Qing-Hong Cao (Peking University)

Slides HIggs2021.pdf

09:30 Higgs bosons in new physics models

Speaker: Prof. Jin Min Yang (ITP, Beijing)

Slides BSM-Higgs-JMYang.pdf

10:00 Heavy neutral scalar searches

Speaker: Lailin Xu (University of Science and Technology of China)

Slides Higgs_NJU_Lailin_202108.pdf

10:30 Coffee Break/茶歇

10:50 Search for heavy Higgs decaying to two tau leptons with the ATLAS detector using pp collision at sqrt(s) = 13 TeV

This talk will cover the latest result of searching for heavy Higgs decaying to two tau leptons with the ATLAS full Run2 datasets using pp collison at $\sqrt(s)$ = 13 TeV. This search is performed over the mass range of 0.2-2.5 TeV and the two $\tau$ leptons decay is considered, where at least one $\tau$ decays leptonically. This channel is sensitive at high $\tan\beta$ value acoording to hMSSM and other 2HDMs, where $\tan\beta$ is the ratio of the vacuum expectation values of the two Higgs. The results of this search show that most of the parameter space of hMSSM is excluded with 95% CL.

Speaker: 瀚非 叶 (Nanjing University)

Slides BSMtautau_ATLAS_HiggsWorkshop_210830.pdf

11:10 Search for doubly and singly charged Higgs bosons decaying into vector bosons in multi-lepton final states with the ATLAS detector using proton--proton collisions at $\sqrt{s}$ = 13 TeV

A search for charged Higgs bosons decaying into $W^{\pm} W{^\pm}$ or $W^{\pm} Z$ bosons is performed, involving experimental signatures with two leptons of the same charge, or three or four leptons with a variety of charge combinations, missing transverse momentum and jets. A data sample of proton--proton collisions at a centre-of-mass energy of 13 TeV recorded with the ATLAS detector at the Large Hadron Collider between 2015 and 2018 is used. The data correspond to a total integrated luminosity of 139 $fb^{-1}$. The search is guided by a type-II seesaw model that extends the scalar sector of the Standard Model with a scalar triplet, leading to a phenomenology that includes doubly and singly charged Higgs bosons. Two scenarios are explored, corresponding to the pair production of doubly charged $H^{\pm\pm}$ bosons, or the associated production of a doubly charged $H^{\pm\pm}$ boson and a singly charged $H^\pm$ boson. No significant deviations from the Standard Model predictions are observed. $H^{\pm\pm}$ bosons are excluded at 95% confidence level up to 350 GeV and 230 GeV for the pair and associated production modes, respectively.

Speaker: Mr hanlin Xu (University of Science and Technology of China)

Slides NJU_Talk08302021.pdf

11:30 Selected results in the 3HDMs

New Physics can manifest itself at colliders in the form of a non-minimal Higgs sector. In particular, the Higgs doublets can also come in generations leading to rich phenomenology. In this talk, I will give a brief overview of the three-Higgs-doublet models (3HDM) focusing on novel model-building opportunities, which go beyond the well studied 2HDM case. I will highlight some recent results related to novel symmetries and their consequences.

Speaker: Prof. Igor Ivanov (SYSU, School of Physics and Astronomy)

Slides Ivanov-Higgs-potential-BSM-workshop.pdf

11:50 Boosted technique for Higgs measurement and New Physics Searches

Highly Lorentz-boosted scalar particles (Higgs or Radion) decaying to bb or WW->4q can be reconstructed as single large-radius jets, and identified using jet substructure and deep neural networks. The techniques can be exploited for both the SM Higgs measurement and New Physics Searches. Two recent applications at the CMS experiments will be covered in this talk, including, 1) a search for standard model Higgs bosons produced with transverse momentum (pT) greater than 450 GeV and decaying to bottom quark-antiquark pairs, and 2) a first search for resonances decaying into a radion and a W boson in proton-proton collision data, with the radion reconstructed through its decay into two W bosons. In the future, we expect to extend these techniques to boosted H->WW and Higgs pair studies. Refs: https://arxiv.org/abs/2006.13251 CMS-PAS-B2G-20-001 CMS-PAS-B2G-21-002

Speaker: Prof. Qiang Li (School of physics, Peking University)

Slides 2021-Nanjing-QL.pdf

12:10 Lunch Break/午餐

14:00 Searches for light scalar and charged scalar

Speaker: Jin Wang (IHEP)

Slides LightChargedHiggs_JinWang_20210830.pdf

14:30 Long-lived Particle(LLP) searching at the future collider

In contrast to the standard model particles, long-lived particles(LLPs) decay with a significant distance from the primary vertex. We present a novel LLPs search strategy based on machine learning (ML) and image recognition techniques utilizing detector information from future lepton colliders.

Speaker: Mr Yulei Zhang (Shanghai Jiaotong University)

Slides Long-Lived_Particle_Search_with_Lepton_Colliders_updated.pdf

14:50 Search for Resonant and Non-resonant VHH Production with ATLAS detector

A search for a vector boson produced in addition to two SM Higgs bosons is studied. Three different models are considered either non-resonant production with SM-like or non-SM-like Higgs self-coupling and hhVV coupling, or resonant production in the form of either VH(hh) or A→ZH(hh). Three sub-channel is considered for different decay mode for vector boson to Zll/Wlv/Zvv final states. Only HH->bbbb decay is considered for statistics and high signal efficiency.

Speaker: Mr Zhongyukun XU (Shandong university)

Slides Search_for_VHH_on_ATLAS_detector-xzyk.pdf

15:10 Coffee Break/茶歇

15:30 Affleck-Dine Leptogenesis from Higgs Inflation

I will present a simple extension of the Standard model to explain the origin of inflation, baryon asymmetry and neutrino masses at the same time.

Speaker: Chengcheng Han (Sun Yat-sen University)

Slides higgsworkshop.pdf

15:50 Higgs Alignment and Novel CP-Violating Observables in 2HDM

Null results from searches for new physics at the Large Hadron Collider (LHC) enforce the belief that new particles must be much heavier than the weak scale. We undertake a systematic study of the interplay between Higgs alignment and CP-violation in complex two-Higgs-doublet models (C2HDMs), which enables us to construct a CP-violating scenario where new Higgs bosons are close to the weak scale after including stringent constraints from the electric dipole moment and measurements at the LHC. In addition, we propose a smoking-gun signal of CP-violation in the Higgs-to-Higgs decay, (h3 → h2h1 → 3h1), where h3,h2, and h1 are the heaviest, second heaviest and the SM-like neutral Higgs bosons, respectively. The mere presence of this decay channel is sufficient to establish CP-violation in C2HDMs. The final state with three 125 GeV Higgs bosons is distinct and provides a unique venue for new measurements at the LHC.

Speaker: Prof. Xiaoping Wang (Beihang University)

Slides Higgs-Nanjing-2021-wangxp.pdf

16:10 BSM Higgs searches in final states with top quarks

Speaker: Dr Nicola Orlando (Barcelona Institute of Science and Technology)

Slides draft_v0_ho.pdf

16:35 Close

Speaker: Dr 雷(Lei) 张(Zhang) (南京大学(Nanjing University))

Slides 20210830_close.pdf