The 4th China LHC Physics Workshop (CLHCP 2018)

19 Dec 2018, 14:00 → 22 Dec 2018, 18:00 Asia/Shanghai

CCNU

The 4th China LHC Physics Workshop (第4届中国LHC物理工作会议) will take place at Central China Normal University in Wuhan from Dec 19 to Dec 22, 2018. The meeting is intended to promote fruitful collaboration between experimentalists and theorists working on physics topics related to the Large Hadron Collider. Registration deadline: November 15, 2018 Abstract submission deadline: November 15, 2018 Registration fee: 1000 CNY for faculty and postdoc 500 CNY for students Workshop Venue: Central China Normal University, Science Hall Onsite registration: December 19, 2018 (Guiyuan Hotel); December 20, 2018 (Science Hall) Local Organizers: Yaxian Mao, Hua Pei, Yuehong Xie, Hang Yin, Daicui Zhou Secretaries: Ya Ma, Qiang Yuan

Accommodation CLHCP2018Accommodation.pdf

Announcement CLHCP2018Announcement_Final.pdf

Transport Travel_information-CLHCP2018.pdf

Wednesday, 19 December

14:00 → 20:00 Registration

Thursday, 20 December

08:00 → 08:30 Registration

08:30 → 10:30 Plenary

Convener: Prof. 代翠 周 (Central China Normal University)

08:30 Welcome

08:40 Speeches from Funding agency

09:00 Report from ALICE

Speaker: Dr Zhongbao Yin (华中师范大学)

Slides 1_ALICEreport1.pdf

09:20 Report from ATLAS

Speaker: Dr 庄胥爱 ZHUANG Xuai (高能所)

Slides ATLAS-CLHCP2018-zhuangxa-v2.pdf

09:40 Report from CMS

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

Slides CMS_QiangLi.pdf

10:00 Report from LHCb

Speaker: Prof. Yuehong Xie (Central China Normal University)

Slides LHCb_CLHCP2018.pdf

10:20 Group Photo

Photo 1220GroupPhoto.jpg

10:30 → 11:00 Group photon and Tea Break

11:00 → 12:40 Plenary

Convener: Prof. Shan Jin (Nanjing University)

11:00 Higgs and New Physics

Speaker: Jiang-Hao Yu (ITP, CAS)

Slides HiggsOverview.pdf

11:24 Highlights of H->VV at the LHC

Speaker: Dr yanping huang (ihep)

Slides 2_2018_wuhan_dec-compressed-3_Huangyanping.pdf

11:48 Highlights of H->ff at the LHC

Speaker: Dr Xin Chen (Tsinghua University)

Slides clhcp2018_xin_v2.pdf

12:12 Search for BSM Higgs

Speaker: Dr Muhammad Ahmad (IHEP)

Slides CLHCP_Wuhan_Ahmad.pdf

12:40 → 14:00 Lunch Break

14:00 → 16:00 Beyond Standard Model

Convener: 昊 ZHANG (Institute of High Energy Physics, Chinese Academy of Sciences)

14:00 SUSY Search activities at IHEP

The institute of high energy physics (IHEP) plays a leading role in various SUSY searches: inclusive and electroweak SUSY searches with light leptons or taus. The talk gives an overview of SUSY search activities at IHEP, as well as the near-future plan and the long-term prospect.

Speaker: Dr Da Xu (IHEP, Beijing)

Slides 2018_IHEP_CLHCP.pdf

14:15 Inclusive and Electroweakino SUSY search with leptons

As the major SUSY search group in China, we have participated in many kinds of SUSY scenario searches including inclusive and electroweakino (EWK) SUSY searches with leptons. This talk shows you the results we had during run2 for inclusive Same-Sign or three lepton (SS/3L) search, inclusive one lepton search, and EWK C1N2/C1C1 with two taus search.

Speaker: Mr Yang LIU (IHEP)

Slides CLHCP.pdf

14:30 Electroweakino SUSY search with Wh

Several analyses searching for chargino and neutralino pair production in different decay final states are ongoing. These searches use 13 TeV datasets collected by the ATLAS and CMS. The results, strategies and outlook of these analyses will be presented.

Speaker: Mr Huajie Cheng (高能所)

Slides CLHCP_SUSY_Wh_18-12-20.pdf

14:45 Search for direct stau production with the ATLAS detector

Supersymmetry (SUSY) is a promising extension of the SM of particle physics. If the chargino and neutralinos are to heavy to be produced, the direct slepton production will be dominant at LHC. Co-annihilation processes favour a light stau that has a small mass splitting with a bino LSP, which can provide a relic density similar current dark matter cosmological observations. This talk gives a brief introduction of searching for the direct stau production using 13 TeV 128 fb-1 ATLAS data collected from 2015 to 2018 and the prospect of searching at the high luminosity LHC with the ATLAS Detector.

Speaker: ChenZheng Zhu (S)

Slides CLHCP_ZHU_DirectStau.pdf

15:00 Extraordinary Gauge Mediaiton and EGM in delfected AMSB

Speaker: Prof. Fei Wang (Department of Physics, ZhengZhou University)

15:15 Neutral Naturalness Models and Phenomenology

We build a minimal neutral naturalness model in which the top partners are not charged under QCD, with a pseudo Goldstone Higgs arising from SO(5)/SO(4) breaking. The color-neutral top partners generate the Higgs potential radiatively without quadratic divergence. The misalignment between the electroweak scale and global symmetry breaking scale is naturally obtained from suppression of the Higgs quadratic term, due to cancellation between singlet and doublet top partner contributions. This model can be embedded into ultraviolet holographic setup in composite Higgs framework, which even realizes finite Higgs potential. Furthermore, we will present collider phenomenology of composite twin Higgs models and minimal composite Higgs models, where the SM top quark can be embedded into various representations of the unbroken global symmetry at UV.

Speaker: Ling-Xiao Xu (Peking University)

Slides slides_CCNU_xulingxiao.pdf

15:30 Naturalness Sum Rules and Their Collider Tests

We present the most general sum rules reflecting the cancellation of ultraviolet divergences in the Higgs potential in weakly-coupled, natural extensions of the Standard Model. There is a separate sum rule for the cancellation of the quadratic and logarithmic divergences, and their forms depend on whether the divergences are canceled by same-spin or opposite-spin partners. These sum rules can be applied to mass eigenstates and conveniently used for direct collider tests of naturalness. We study in detail the feasibility of testing these sum rules in the top sector at a future 100 TeV proton collider within two benchmark models, the Little Higgs (LH) and the Maximally Symmetric Composite Higgs (MSCH). We show how the two ingredients of the sum rules, the top partner masses and their Yukawa couplings to the Higgs, can be measured with sufficient accuracy to provide a highly non-trivial quantitative test of the sum rules. In particular, we study observables sensitive to the sign of the top partner Yukawa, which is crucial for verifying the sum rules but is notoriously difficult to measure. We demonstrate that in the benchmark models under study, a statistically significant discrimination between the two possible signs of each Yukawa will be feasible with a 30 ab−1 data set at 100 TeV.

Speaker: Prof. Jing Shu (ITP-CAS)

Slides JingShu.pdf

15:45 Search for SM di-Higgs and BSM heavy Higgs resonant in WWyy channel on ATLAS detector with 36.1/fb

Di-Higgs production is important for Higgs self-coupling measurement, BSM heavy Higgs search and search for anomalous coupling etc. WWyy has clean background and good mass resolution from diphoton final state and large branching ratio from WW. A search for di-Higgs is performed on ATLAS detector with 36 $fb^{-1}$ dataset. The upper limit is set.

Speaker: ZHANG Yu (IHEP)

Slides Yu_Zhang_CLHCP2018.pdf

14:00 → 16:00 Heavy Flavor

Convener: Dr Zhenwei Yang (Tsinghua University, Beijing, China)

14:00 Pentaquark study at LHCb

I will review the pentaquark study at LHCb and show the prospect with full LHCb data taking from 2011 to 2018.

Speaker: Prof. Liming Zhang (Tsinghua University)

Slides CLHCP-2018.pptx

14:15 Foot Prints of New Physics in b->cτν Transitions

In this work, we perform a combined analysis of the R(D), R(D*) and R(J/psi) anomalies in a model-independent manner based on the general framework of the four-fermion effective field theory, with paying special attention to the employ of the hadronic form factors. For the B->D(D*) transition form factors, we use the HQET parametrization that include the higher order corrections of O(lambda_QCD/m,alpha_s) and determined recently from a fit to lattice QCD and light-cone sum rule results in complementary kinematical regions of the momentum transfer. For the Bc->J/psi(eta_c) transitions, we use the form factors calculated in the covariant light-front quark model, which are found to be well consistent with the preliminary lattice results. From our analysis, the two classes of vector operators are shown to be the most favored single new physics (NP) operators by the current experimental constraints within 2sigma and the LEP1 data on Br(Bc->τν) as well as the minimum chi^2 fit, while the tensor operator is also allowed but severely constrained, and the scalar ones are excluded. Using the favored ranges and fitted values of the Wilson coefficients of the single NP operators, we also give prognosis for the physical observables such as the ratios of decay rates R(D(D*), R(J/psi(eta_c)) and other polarized observables as well as the q2 distributions.

Speaker: Mr Zhuoran Huang (IHEP)

Slides 2_presentation_1.pdf

14:30 First observation of the doubly charmed baryon decay Xicc++→Xic+pi+

The doubly charmed baryon decay Xicc++->Xic+pi+ is observed for the first time, with a statistical significance of 5.9σ, confirming a recent observation of the baryon in the Lambdac+k-pi+pi+ final state. The data sample used corresponds to an integrated luminosity of 1.7fb−1, collected by the LHCb experiment in pp collisions at a center-of-mass energy of 13TeV. The Xicc mass is measured to be 3620.6±1.5(stat)±0.4(syst)±0.3(Xic+)MeV/c2, and is consistent with the previous result. The ratio of branching fractions between the decay modes is measured to be 0.035±0.009(stat)±0.003(syst).

Speaker: Menglin Xu (Central China Normal University)

Slides 3_CLHCP_Xicc2Xicpi.pdf

14:45 Measurement of the lifetime of the doubly charmed baryon Xicc++ at LHCb

The Doubly charmed baryon $\Xi_{cc}^{++}$ was observed by the LHCb experiment in 2017. Measurements of its properties will allow for precise tests of QCD, the theory of strong interactions, in a unique environment. In this talk, we present the first measurement of the lifetime of the doubly charmed baryon $\Xi_{cc}^{++}$, with signals reconstructed in the final states $\Lambda_c^+ K^- \pi^+ \pi^+$ from the data sample collected by the LHCb experiment, corresponding to an integrated luminosity of 1.7 fb$^{-1}$. The measured $\Xi_{cc}^{++}$ lifetime is $0.256^{+0.024}_{-0.022} \pm 0.014$ ps.

Speaker: Mr Ao Xu (清华大学)

Slides axu-xicclifetime.pdf

15:00 Measurement of Υ production in pp collisions at √s = 13TeV

The production cross-sections of $\Upsilon(1S)$, $\Upsilon(2S)$ and $\Upsilon(3S)$ mesons in proton-proton collisions at $\sqrt{s}=13$ TeV are measured with a data sample corresponding to an integrated luminosity of $277 ± 11$ pb$^{−1}$ recorded by the LHCb experiment in 2015. The $\Upsilon$ mesons are reconstructed in the decay mode $\Upsilon\to\mu^{+}\mu^{-}$. The differential production cross-sections times the dimuon branching fractions are measured as a function of the $\Upsilon$ transverse momentum, $p_{\rm T}$, and rapidity, $y$, over the range $0 < p_{\rm T} < 30$ GeV/$c$ and $2.0 < y < 4.5$. The ratios of the cross-sections with respect to the LHCb measurement at $\sqrt{s}=8$ TeV are also determined. The measurements are compared with theoretical predictions based on NRQCD.

Speaker: Mr jiajia Qin (中国科学院大学物理学院)

Slides UpsilonProduction@13TeV4thCLHCP.pdf

15:15 Study of underlying event in top quark pair production in pp collisions at 13 TeV

The first measurements of the underlying event activity in top quark and antiquark pair production are presented. The measurements are performed in proton-proton collisions at a center-of-mass energy of 13 TeV, and are based on data collected by the CMS experiment at the LHC in 2016 corresponding to an integrated luminosity of 35.9 fb-1. In each event, the contribution from the underlying event is isolated using particle-flow reconstruction by removing charged particles associated with the decay products of the top quark pair candidates as well as with pileup interactions from the reconstructed charged particles. The measurements are done using observable that enhance the sensitivity to the modelling of multipparton interactions, colour reconnection and the choice of the strong coupling parameter in the PYTHIA8 parton shower code. These measurements characterise, for the first time, the underlying event in top quark pair production and test the universality hypothesis at energy scales typically higher than the ones at which model parameters have been determined.

Speaker: Dr Jianguo Bian (IHEP)

Slides Bian_Yazgan_CLHCP.pdf

15:30 CP asymmetries in charm decays into neutral kaons

A new $CP$-violation effect is found in charm decays into neutral kaons: the interference between two tree (Cabibbo-favored and doubly Cabibbo-suppressed) amplitudes with the mixing of final-state mesons. This effect, estimated to be of order of $10^{-3}$, is much larger than the direct $CP$ asymmetries in these decays, but missed in the literature. It can be revealed by measuring the difference of the time-dependent $CP$ asymmetries in the $D^{+}\to \pi^{+}K_S^0$ and $D_{s}^{+}\to K^{+} K_S^0$ modes, which are accessible at the LHCb and Belle II. If confirmed, the new effect has to be taken into account, as the above direct $CP$ asymmetries are used to search for new physics.

Speaker: Mr Di Wang (School of Nuclear Science and Technology, Lanzhou University)

Slides wangd11@lzu.edu.cn

15:45 Flavor Violating Higgs Yukawa Couplings in Minimal Flavor Violation

Speaker: Prof. Xing-Bo Yuan (Central China Normal University)

Slides Higgs_MFV

14:00 → 16:00 Heavy Ion Physics

Convener: Dr Guo-Liang Ma (Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China)

14:00 Tale of coherent photon products: from UPC to HHIC

The coherent photon-nucleus and photon-photon interactions has been studied in detail to probe the gluon distribution in nucleus and to test QED via relativistic heavy-ion collisions. These kind of interactions are traditionally thought to be only exist in ultra-peripheral collisions (UPC), where there is no hadronic interactions. Recently, significant excess of $J/\psi$ yield and dielectron pair production at very low transverse momentum ($p_{T} <$ 0.3 GeV/c) were observed by the ALICE and STAR collaborations in peripheral A+A collisions, which points to evidence of coherent photon products in hadronic heavy-ion collisions (HHIC). The possible survival of photoproduced $J/\psi$ and electron pair merits theoretical investigations, which are currently rare on the market. In this talk, we report on calculations of $J/\psi$ yield from coherent photon-nucleus interactions and dilepton production from photon-photon interactions in HHIC at RHIC and LHC energies. The model used to calculate the cross section is discussed and the expected yield are compared with experimental results from RHIC and LHC. We predict the coherent production contribution of $J/\psi$ and dielectron from isobaric collisions (Ru+Ru, Zr+Zr) for the further experimental test at RHIC.

Speaker: 王妹 查 (中国科学技术大学近代物理系)

Slides CLHCP_wangmei.pdf CLHCP_wangmei.pptx

14:15 Measurements of heavy-flavour decay leptons in Pb-Pb and Xe-Xe collisions with ALICE at the LHC

In this talk, measurements of RAA and v2 of open heavy-flavour hadrons via semi-leptonic decays to electrons at mid-rapidity and muons at forward rapidity in Pb-Pb collisions at LHC energies will be discussed. The progresses on the analysis of the production and anisotropy of electrons from beauty-hadron decays will be also discussed. In addition the RAA of heavy- flavour hadron decay leptons in Xe-Xe collisions will be presented, along with the prospects for measuring the total charm cross section in this collision system. Comparisons with model calculations including the interaction of heavy quarks with the hot, dense, and deconfined medium will be also shown.

Speaker: ZUMAN ZHANG (ccnu)

Slides 2_ALICE_open_HF_lepton_HP20181220.pdf

14:30 Non-strange and strange D-meson and charm-baryon production in heaavy-ion collisions measured with ALICE at the LHC

Heavy quarks (charm and beauty) are a powerful probe of the Quark-Gluon Plasma (QGP) formed in high-energy heavy-ion collisions. They are produced in hard scattering processes on a timescale shorter than the QGP formation time and experience the whole system evolution. The measurement of the nuclear modification factor ($R_{\rm AA}$) of open heavy flavours can provide important information about the microscopic interactions of heavy quarks with the medium constituents, in particular on the colour-charge and parton-mass dependence of heavy-quark energy loss. The measurements of the elliptic flow ($v_{2}$) at low $p_{\rm T}$ can give insight into the participation of the heavy quarks to the collective expansion of the system and their thermalization in the medium. These two observables can also help in understanding possible modifications of heavy-quark hadronisation in the medium. In particular, the role of the recombination mechanism can be studied for charm via the comparison of D mesons without strange-quark content with D$^+_{\rm s}$ and charm baryons. Measurements of charm-baryon production in pp and p--Pb collisions are also essential to establish a baseline for Pb--Pb collisions. The measurements in pp collisions provide critical tests of models of charm hadronisation in vacuum and the measurements in p--Pb collisions are useful to study cold nuclear matter effects. In this talk, the latest results on $p_{\rm T}$-differential $R_{\rm AA}$ and $v_2$ of D mesons measured at mid-rapidity in Pb-Pb collisions with ALICE will be presented. The $p_\mathrm{T}$-differential cross section of the $\Lambda_{c}^+$ baryon in pp and p--Pb collisions will be presented. Finally, the $\Lambda_{\rm c}^+$ production in Pb--Pb collisions will be shown. The measurements will be compared with model predictions.

Speaker: xinye peng (Central China Normal University)

Slides 3lhcp2018-xinye.pdf 3lhcp2018-xinye.pdf

14:45 Open heavy flavor production in pPb collisions at LHCb

Production of open heavy flavor in pPb collisions provides insight on the cold nuclear matter effects, and acts as a crucial reference measurement to AA collisions in order to disentangle cold nuclear matter effects from the QGP-related effects. The LHCb experiment has measured the production cross section of open charm and beauty hadrons in proton-lead collisions in the forward rapidity region. The measurements use data samples of pPb collisions at \sqrt{s_{NN}}=5.02 TeV and 8.16 TeV, collected by the LHCb detector in 2013 and 2016, respectively. In this talk we present the nuclear modification factors R_{pPb} of D^{0} and B^{+}, the baryon to meson ratio and the forward-backward production ratio R_{FB} for open charm and beauty states.

Speaker: Dr Jiayin Sun (Tsinghua University)

Slides clhcp2018_ohf_pPb_sun.pdf

15:00 Nuclear modification of full jets and jet structure in PbPb collisions at the LHC

With our coupled jet-fluid model [1, 2, 3], we study the nuclear modifications of full jets and jet structures for single inclusive jet, dijet and gamma-jet events in Pb+Pb collisions at both 2.76 TeV and 5.02 TeV. The evolution of full jet shower is studied via a set of coupled transport equations including the effects of collisional energy loss, transverse momentum broadening and medium-induced splitting process. The dynamical evolution of the bulk medium is simulated via hydrodynamic equation with source terms which describe the energy and momentum deposited from hard jet to soft medium. Our detailed analysis indicates that collisional absorption contributes most to full jet energy loss and tends to narrow the jet shape function, while transverse momentum kicks and medium-induced radiations contribute less energy loss and broaden the jet transverse profile. Also, jet-induced flow plays a significant contribution to jet shape function and dominates at large angles away from the jet axis. The final nuclear modification pattern for the jet shape function is a combined effect from various jet-medium interaction mechanisms. Our detailed studies for single inclusive jets, dijets and gamma-jets for various kinematics indicate that the nuclear modification of jet shape is sensitive to jet energy and collision energy, and not much sensitive to jet flavor. Reference: [1] Ning-Bo Chang, Guang-You Qin, Phys.Rev,C94,024902 (2016) [2] Yasuki Tachibana, Ning-Bo Chang and Guang-You Qin, Phys.Rev,C95,044909 (2017) [3] Ning-Bo Chang, Guang-You Qin, Yasuki Tachibana, in preparation

Speaker: Ning-Bo Chang (Xinyang Normal Univerisity)

Slides changnb-CLHCP-v3.pdf changnb-CLHCP-v3.pptx

15:15 Measurements of charged jet production and modification in ALICE

A jet is a spray of collimated hadrons originated in the fragmentation of an energetic parton. The cross section measurement provides a good test for pQCD calculations, and jet production in pp collisions constitutes a reference for jet quenching study in nucleus-nucleus collisions. In addition, the measurements in different multiplicity intervals will provide insights to understand the properties of small interacting system. In this communication, we will present charged jet cross section measurement in pp collisions at 13 TeV with high statistics collected by ALICE. The jet cross section ratio for various jet resolution parameters will be also shown. Such kind of cross section ratio is an indirect measurement of the jet shape. In particular, we will present the charged particle jet production in different multiplicity intervals, which will provide important input for understanding the correlations between the hard process and event activity in small system.

Speaker: Ms Yongzhen HOU (presentation)

Slides CLHCP1220_yongzhen.pdf

15:30 Jet-like Correlations in Au+Au Collisions at $\sqrt{s_{NN}}=200$ GeV in STAR

Hard scattered partons lose their energy when propagating through the hot dense medium created in relativistic heavy ion collision. Jets are excellent probes to study parton energy loss mechanisms. Experimentally high transverse momentum ($p_T$) trigger particles are taken as proxies of jets. Di-hadron correlation measurements in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV will be presented in this talk, where all orders of flow background are subtracted using data themselves. They are used to study how the lost energy is redistributed at low to modest $p_T$. Moreover, the path length dependence of the parton energy loss can provide deeper understanding of the energy loss mechanisms. Di-hadron correlations as a function of both the azimuthal angle of the trigger particle with respect to the event plane and Event Shape Engineering selections will also be presented. These results will shed new lights on the path length and geometry dependence of jet-medium interactions.

Speaker: Mr Kun Jiang (University of Science and Technology of China)

Slides CLHCP2018_Kun.pdf

15:45 Gluon emission from heavy quarks in dense nuclear medium

We study the medium-induced gluon emission process experienced by a hard jet parton propagating through dense nuclear matter in the framework of deep inelastic scattering off a large nucleus. We work **beyond collinear rescattering expansion and soft gluon emission limit**, and derive **a closed formula for medium-induced single gluon emission from a heavy or light quark jet** interacting with dense nuclear medium *via transverse and longitudinal scatterings*. Without performing collinear expansion, **the medium-induced gluon emission spectrum is controlled by the full distribution of the differential elastic scattering rates** between the propagating partons and medium constituents. We further show that if one utilizes heavy static scattering centers for traversed nuclear matter and takes soft gluon emission limit, **our result can reduce to the first order in opacity Djordjevic-Gyulassy-Levai-Vitev formula**.

Speaker: 乐 张 (Hubei Normal University)

Slides 8Zhang_Le_CLHCP2018.pptx

16:00 → 16:30 Tea Break

16:30 → 18:00 Beyond Standard Model

Convener: Haijun Yang (Shanghai Jiao Tong University)

16:30 Constraining Gluonic Quartic Gauge Coupling Operators with gg→γγ

Gluon-gluon to photon-photon scattering gg→γγ offers to the LHC experiments a uniquely powerful probe of dimension-8 operators in the Standard Model Effective Field Theory (SMEFT) that are quadratic in both the electromagnetic and gluonic field-strength tensors, such as would appear in the Born-Infeld extension of the Standard Model (SM). We use 13-TeV ATLAS data on the production of isolated photon pairs to set lower limits on the scales of dimension-8 operators M≳1TeV, and discuss the prospective sensitivities of possible future hadron colliders.

Speaker: Dr Shao-Feng Ge (IPMU & UC Berkeley)

Slides CLHCP18.pdf

16:45 Low-mass diphoton resonances search with the ATLAS detector at 13 TeV

Several models beyond the standard model (BSM) predict new resonances decaying into two photons. The diphoton final state has the advantage of a clean experimental signature with an excellent mass resolution and moderate background. Using this final state, the CMS Collaboration observed a small excess near 95 GeV with a local (global) significance of 2.8 (1.3) standard deviations when combining data recorded at 8 TeV and 13 TeV. A search for a narrow diphoton resonance X of mass mX is also performed by ATLAS experiment in the low-mass range 65 to 110 GeV, below the SM Higgs boson mass of 125 GeV, using 80 fb$^{−1}$ of pp collision data recorded at 13 TeV at the Large Hadron Collider. In this range, in addition to the smoothly falling continuum background composed of photon pairs (γγ), as well as photon–jet (γj) and jet pairs (jj) with mis-identified jets, a Drell-Yan (DY) component is present. The events are split into three categories depending on how the two photon candidates are reconstructed. A model composed of analytic functions that describe the signal and background (including γγ, γj, jj and DY) is fit to the measured diphoton mass spectrum to search for narrow resonances. The dominant uncertainties arise from the uncertainty due to the choice of analytic functions to model the continuum background. No significant excess with respect to the Standard Model expectation is found in ATLAS experiment, and a limit at the 95% confidence level is set on narrow resonance fiducial cross-section times branching ratio ranging from 30 to 101 fb.

Speaker: Asma Hadef (University of Science and Technology of China)

Slides AsmaHadef-CLHCP2018-talk.pdf

17:00 Search for heavy resonance decaying to Z/W/H+photon with the ATLAS detector

This talk will present a search for heavy resonance decaying to Z/W/H + an energetic photon using 36.1 fb$^{-1}$ pp collision data collected by the ATLAS detector. Only the hadronic decays of Z/W/H bosons are considered. This search explores the phase space where the boson decay products are close and form a fat jet. No obvious deviations are found with respect to the Standard Model predictions. The model-independent cross section limits are presented as functions of resonance mass for various signal hypotheses.

Speakers: Bo Liu (IHEP) , bo liu (IHEP)

Slides VgammaHadronic_CLHCP.pdf

17:15 Search for resonant W Z production in the fully leptonic final state in proton–proton collisions at √ s = 13 TeV with the ATLAS detector

A search for a heavy resonance decaying into WZ in the fully leptonic channel (electrons and muons) is performed. It is based on proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 36.1 fb−1 . No significant excess is observed over the Standard Model predictions and limits are set on the production cross section times branching ratio of a heavy vector particle produced either in quark-antiquark fusion or through vector-boson fusion. Constraints are also obtained on the mass and couplings of a singly charged Higgs boson, in the Georgi–Machacek model, produced through vector-boson fusion

Speaker: Mr Miaoran Lu (USTC)

Slides WZresonance_Miaoran.pdf

17:30 Search for new physics via top quark production in dilepton final state at 13 TeV

A search for new physics in top quark production is performed in proton-proton collisions at 13 TeV. The data set corresponds to an integrated luminosity of 35.9 fb^-1, and was collected in 2016 by the CMS detector. Events with two opposite-sign isolated leptons (electrons or muons) and b quark jets in the final state are selected. The search is sensitive to new physics in top quark pair production and in single top quark production in association with a W boson. This is the first search for new physics that uses the tW process. No significant deviation from the standard model expectation is observed. Results are interpreted in the framework of an effective field theory and constraints on the relevant effective couplings are set using a dedicated multivariate analysis.

Speaker: Mr Wenxing Fang (Beihang University)

Slides CLHCP_2018_v2.pdf

17:45 Search for lepton-flavor violation in emu, etau and mutau final states

A search is performed for a heavy particle decaying into different-flavor, dilepton pairs ($e\mu$, $e\tau$ or $\mu\tau$), using 36.1$fb^{-1}$ of proton--proton collision data at $\sqrt{s}=13$~TeV collected in 2015--2016 by the ATLAS detector at the Large Hadron Collider. No excesses over the Standard Model predictions are observed. Bayesian lower limits at the 95\% credibility level are placed on the mass of a \Zprime boson, the mass of a supersymmetric $\tau$-sneutrino, and on the threshold mass for quantum black-hole production. For the $Z'$ and sneutrino models, upper cross-section limits are converted to upper limits on couplings, which are compared with similar limits from low-energy experiments and which are more stringent for the $e\tau$ and $\mu\tau$ modes.

Speaker: Dr Marc Bret Cano (Shanghai Jiao Tong university)

Slides presentation_Wuhan_cLHCP2018.pdf

16:30 → 18:00 Heavy Ion Physics

Convener: Prof. 笙琴 冯 (三峡大学理学院)

16:30 Simple analytical solutions of relativistic hydrodynamics with longitudinal accelerating flow

We will present new, exact, finite solutions of relativistic hydrodynamics for longitudinally expanding fireballs for arbitrary constant value of the speed of sound (CKCJ). These new solutions generalize earlier, longitudinally finite, exact solutions, from an unrealistic to a reasonable equation of state, characterized by a temperature independent (average) value of the speed of sound. Observables such as the rapidity density and the pseudorapidity density are evaluated analytically, resulting in simple and easy to fit formulae that can be matched to the high energy proton--proton and heavy ion collision data at RHIC and LHC. In the longitudinally boost-invariant limit, these new solutions approach the Hwa--Bjorken solution and the corresponding rapidity distributions approach a rapidity~plateaux. Also, we will present a perturbative solution of viscous hydrodynamics which included the longitudinal acceleration. The charged-particle's final state spectrum is derived from an analytic perturbative solution for the relativistic viscous hydrodynamics. By taking into account the longitudinal acceleration effect in relativistic viscous hydrodynamics, the pseudorapidity spectrum describes well the nucleus-nucleus colliding systems at RHIC and LHC. Based on both the extracted longitudinal acceleration parameters $\lambda^{*}$ and a phenomenological description of the $\lambda^{*}$, the charged-particle's pseudorapidity distributions for $\sqrt{s_{NN}}$ = 5.44 TeV Xe+Xe collisions are computed from the final state expression in a limited space-time rapidity $\eta_{s}$ region. Summary We published above results at Phys. Rev. C 97, 064906 https://journals.aps.org/prc/abstract/10.1103/PhysRevC.97.064906 and Universe 2018, 4(6), 69 (analytical solutions for ideal hydroddynamics) http://www.mdpi.com/2218-1997/4/6/69 and a paper accepted by Chinese Physics C https://arxiv.org/abs/1808.10287 and two papers submitted to APPB https://arxiv.org/abs/1806.05750 https://arxiv.org/pdf/1806.06794.pdf

Speaker: Ze-Fang Jiang (Central China Normal University)

Slides JiangZF-CLHCP-V1-web.pdf

16:45 Anisotropic flow of identified particles in Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV with ALICE

Anisotropic flow plays a critical role in understanding the properties of the quark-gluon plasma. The elliptic and triangular flow of identified particles, including $\pi^{\pm}$, $\rm K^{\pm}$, $\rm p +\bar{p}$, $\phi$, $\rm K^{0}_{S}$, $\Lambda + \bar{\Lambda}$, $\Xi^{-}+\bar{\Xi}^{+}$ and $\Omega^{-}+\bar{\Omega}^{+}$ were measured by ALICE for Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV. The measurements are presented at mid-rapidity for a wide range of particle transverse momenta. The results are compared to those for elliptic and triangular flow in Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV.

Speaker: Ya Zhu (CCNU)

Slides 2-CLHCP2018.pdf

17:00 Longitudinal decorrelations of anisotropic flow and $\gamma$-Jet induced rapidity even direct flow

We perform a systematic study on the decorrelation of anisotropic flows along the pseudorapidity in relativistic heavy-ion collisions at the LHC and RHIC energies.The dynamical evolution of the QGP fireball is simulated via the CLVisc (3+1)D hydrodynamics model, with the fully fluctuating initial condition from AMPT model. Detailed analysis is performed on the longitudinal decorrelations of elliptic, triangular and quadrangular flows in terms of flow vectors, flow magnitudes and flow orientations (event planes). It is found that pure flow magnitudes have smaller longitudinal decorrelation than pure flow orientations, and the decorrelation of flow vectors is a combined effect of both flow magnitudes and orientations. The longitudinal decorrelation of elliptic flow has a strong and non-monotonic centrality dependence due to the initial elliptic collision geometry: smallest decorrelation in mid-central collisions. In contrast, the decorrelations of triangular and quadrangular flows have weak centrality dependence, slightly larger decorrelations in more peripheral collisions. Our numerical results for Pb+Pb collisions at the LHC are in good agreement with the ATLAS data, while our RHIC results predict much larger longitudinal decorrelations as compared to the LHC. We further analyze the longitudinal structures of the AMPT initial conditions and find that the final-state longitudinal decorrelation effects are strongly correlated with the lengths of the initial string structures in the AMPT model. The decorrelation effects are typically larger at lower collision energies and in more peripheral collisions due to shorter lengths of the string structures in the initial states. Meanwhile, we have a brief study about $\gamma$ -Jet induced even direct flow. And we find that the jet energy loss will lead to larger direct flow $v_1$ for peripheral collision, but for central collision, the jet energy loss effect is small compared due to the large size of medium.

Speaker: Xiang-Yu Wu (Central China Normal University)

Slides clhcp_wxy.pdf

17:15 Machine Learning rediscovers flow in simulated data of heavy ion collisions

We apply principal component analysis(PCA) to simulated data of relativistic heavy-ion collisions. Unlike traditional Fourier methods, we apply PCA directly to single particle distribution. Interesting patterns are identified by PCA as eigenmodes, from which we define new flow observables $v_n^{'}$ compared to traditional ones $v_n$. The eigenmodes are very much like traditional Fourier bases, but are slightly different. Further research shows that $v_n^{'}$ are mutually more independent than $v_n$. We then relate $v_n^{'}$ to initial eccentricity $\varepsilon_n$, finding $v_n^{'}$ do have more linearity with $\varepsilon_n$ than $v_n$ with $\varepsilon_n$. This might be a signature that relativistic hydrodynamics is not as non-linear as we originally thought. With new bases chosen by PCA, the correlations between different harmonics drop significantly.

Speaker: Mr Ziming Liu (Peking University)

Slides 4PCA_Ziming.pdf

17:30 Spectra and flow of light nuclei in relativistic heavy ion collisions at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

Within the framework of the coalescence model based on the phase-space distributions of protons and neutrons generated from the {{\tt iEBE-VISHNU}} hybrid model with {{\tt AMPT}} initial conditions, we study the spectra and elliptic flow of deuterons and helium-3 in relativistic heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Larger Hadron Collider (LHC). Results from our model calculations for Au + Au collisions at $\sqrt{s_{NN}}=200$ GeV at RHIC and Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV at the LHC are compared with available experimental data. Good agreements are generally seen between theoretical results and experimental data, except that the calculated yield of helium-3 in Pb + Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV underestimates the data by about a factor of two. Possible reasons for these discrepancies are discussed. We also make predictions on the spectra and elliptic flow of deuterons and helium-3 in Pb + Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV that are being studied at LHC.

Speaker: Wenbin Zhao (school of physics Peking Uniersity)

Slides light_nuclei_wuhan.pdf

17:45 Properties of light (anti)nuclei production in Pb-Pb collisions at LHC energy

The Large Hadron Collider (LHC) at the European Organization for Nuclear Research(CERN) can provide a good experimental condition to study the production of light (anti) nuclei and to understand the underlying physical mechanisms for collision physics.The centrality dependence of light (anti)nuclei and (anti)hypertriton production in Pb-Pb collisions at LHC energy are investigated using the dynamically constrained phase-space coalescence(DCPC) model and the parton and hadron cascade (PACIAE) model. We find that the yields of light (anti)nuclei and (anti)hypertriton strongly depend on the centrality, i.e., their yields decrease rapidly with the increase of centrality; but their yield ratios are independent of centrality. The results from our theoretical model are well consistent with ALICE data. Furthermore, the integrated yields of (anti)nuclei per participant nucleon increase from peripheral to central collisions, and a higher mass number corresponds to a more rapid increase of these yields. The coalescence parameters (BA) of light (anti)nuclei and (anti)hypernuclei are also analyzed. In addition, nuclear modification factors (RAA or RCP) and the number-of-nucleon scaling of (anti-)proton and (anti-)deuteron has also been discussed.

Speaker: Mr Zhilei SHE (China University of Geosciences(wuhan))

Slides Shezhilei_workshop_IN_CCNU.ppt

16:30 → 18:00 Standard Model and Electroweak

Convener: Yusheng Wu (University of Science and Technology of China)

16:30 Performance of the hadronic recoil in precision W boson measurements with low pileup dataset

A study of the performance of the hadronic recoil in inclusive W and Z boson production is presented. The dataset used corresponds to low pileup LHC runs taken between 2017 and 2018, at both centre-of-mass energies of 5 and 13 TeV. The results show that the resolution is optimal when using the maximal phase space available for the particle clusters in the detector. And an optimization of the impact parameter cuts for leptons is performed.

Speakers: Dr Javier Merino (Institute of High Energy Physics) , Mr Mengran Li (Institute of High Energy Physics)

Slides CLHCP_Mengran.pdf

16:45 Measurement of the differential cross section of Z boson production in association with jets at CMS

The measurement of the differential cross section of Z boson production in association with jets (Z+jets) in proton-proton collision at the center-of-mass energy of 13 TeV will be present. The data has been recorded with the CMS detector at the LHC during the year 2015, corresponding to an integrated luminosity of 2.19 fb−1. The goal of analysis is to perform a first measurement at 13 TeV of the cross sections of Z+jets as a function of the jet multiplicity, its dependence on the transverse momentum of the Z boson, the jet kinematic variables (transverse momentum and rapidity), the scalar sum of the jet momenta, and the balance in the transverse momentum between the reconstructed jet recoil and the Z boson. The results are obtained by correcting the detector effects, and are unfolded to particle level. The measurement are compared to four predictions using different approximations: at the leading-order (LO), next-to-leading-order (NLO) and next-to-next-to-leading order (NNLO) accuracy. The first two calculations used {\sc MadGraph5_aMC@NLO} interfaced with {\sc pythia8} for the parton showering and hadronisation, one of which includes matrix elements (MEs) at LO, another includes one-loop corrections (NLO). The third is a fixed-order calculation with NNLO accuracy for Z+1 jet using the N-jettiness subtraction scheme (Njetti). The fourth uses the {\sc geneva} program with an NNLO calculation combined with higher-order resummation. Key words: physics, CMS, standard model, Quantum Chromodynamics, cross section, Z boson, jets, {\sc MadGraph5_aMC@NLO}, {\sc geneva}

Speaker: Ms Qun WANG (Peking University)

Slides ZJets_CLHCP2018.pdf

17:00 Recent measurements of the Zgamma production with the ATLAS detector

The production of Z bosons in association with a high-energy photon is studied in the neutrino decay channel of the Z boson using pp collisions at √ s = 13 TeV. The analysis uses a data sample with an integrated luminosity of 36.1 fb−1 collected by the ATLAS detector at the LHC in 2015 and 2016. Candidate Zγ events with invisible decays of the Z boson are selected by requiring significant transverse momentum (pT) of the dineutrino system in conjunction with a single isolated photon with large transverse energy (ET). The rate of Zγ production is measured as a function of photon ET, dineutrino system pT and jet multiplicity. Evidence of anomalous triple gauge-boson couplings is seen in Zγ production with photon ET greater than 600 GeV. No excess is observed relative to the Standard Model expectation, and upper limits are set on the strength of ZZγ and Zγγ couplings.

Speaker: Dimitrii Krasnopevtsev (University of Science and Technology of China)

Slides Krasnopevtsev_Dimitrii_CLHCP_Zgamma.pdf

17:15 Observation of electroweak production of a same-sign W boson pair in association with two jets in pp collisions with the ATLAS detector

The talk will present an observation of electroweak production of a same-sign W boson pair in association with two jets using 36.1 fb−1 of proton-proton collision data recorded by the ATLAS detector at a center-of-mass energy of 13 TeV. Events containing two same-sign leptons, electron or muon, and at least two jets, are selected.

Speaker: Ms liqing zhang (University of Science and Technology of China)

Slides 18.12.20-CLHCP2018-12+3.pdf

17:30 New VBS observations at LHC

At ICHEP2018 conference, ATLAS presented its first observations of same-sign WW and WZ vector boson scattering processes, the latter of which was considered as the 1st observation of such process at LHC, leading to a collaboration wide highlight at the ICHEP2018 conference. It is a very important milestone to probe the SM-EWK symmetry breaking and Higgs unitarization mechanism in the VBS processes. The summary is written by the collaboration as physics briefing: http://atlas.cern/updates/physics-briefing/weak-lightsabers The talk will present such progress with details and future prospects.

Speaker: Elena Yatsenko (Shanghai Jiao Tong University)

Slides VBS_CLHCP2018_ElenaYatsenko.pdf

17:45 Calibration of Quark versus Gluon Jet Tagging Variables Using Two Event Topologies with the ATLAS Detector

Distinguishing quark-initiated from gluon-initiated jets is useful for many measurements and searches at the LHC. Development of tools for distinguishing quark- from gluon-initiated jets are potentially useful. However, there arises difficulty from the topology dependence of quark-versus-gluon jet tagging.The dijet topologies either dijet back to back or djet plus a gamma (quark dominated) or dijet plus a third jet (gluon dominated) should be used to output the quark and gluon tagging efficiencies as function of the jet pT and eta, in both data and simulation and will be used to derive also scale factors for the Monte Carlo rejections and efficiencies.

Speaker: Wanyun Su (Shanghai Jiao Tong University)

Slides CLHCP2018_ws.pdf

18:00 → 19:00 Dinner

19:00 → 21:00 Public Lecture in CCNU by Prof. Gao Yuanning

Convener: Prof. Yuehong Xie (Central China Normal University)

slides Lecture_YuanningGao.pdf

Friday, 21 December

08:30 → 10:30 Plenary

Convener: Prof. Guoming 陈国明 (高能所)

08:30 Current Status of SUSY

Speaker: Dr Junjie Cao (Henan Normal University)

Slides Junjie-Cao.pdf

08:54 Search for SUSY

Speaker: Dr Antonios Agapitos (Peking Univ. (CN))

Slides SUSY__21_12_18__v4.pdf

09:18 Search for Exotics

Speaker: Prof. Liang Li (Shanghai Jiao Tong University)

Slides Extoics_Search_ATLAS_CMS_[CLHEP2018]_20181221.pdf

09:42 Overview of SM EW measurements at LHC

Speaker: Rustem Ospanov (USTC)

Slides rospanov_clhcp.pdf

10:06 LHC实验顶夸克物理最新进展

This talk presents the most up-to-date results on top physics with LCH experiment.

Speaker: Jin Wang (IHEP)

Slides TOPLHC_JinWang_20181221.pdf

10:30 → 11:00 Tea Break

11:00 → 12:36 Plenary

Convener: Prof. Yuanning Gao (Peking University)

11:00 Hadron Production at the LHCb

Hadron Production at the LHCb

Speaker: Dr Xianglei Zhu (Tsinghua University)

Slides zhu_CLHCP_2018_v2_nobackup.pdf

11:24 CPV and Rare decays at the LHCb

Speaker: 文斌 钱 (University of Chinese Academy of Sciences)

Slides Wenbin_Qian_CLHCP.pdf

11:48 Exotic hadrons and doubly heavy baryons at LHCb

Speaker: Dr 航 尹 (华中师范大学)

Slides CLHCP_Exotic_DHB_LHCb.pdf

12:12 Recent Theoretical Progresses on Heavy Flavor Physics

Speaker: Prof. Wei Wang (Shanghai JiaoTong University)

Slides WeiWang.pdf

12:36 → 14:00 Lunch Break

14:00 → 16:00 Detector performance and upgrade

Convener: Prof. Xiaomei Li (China Institute of Atomic Energy)

14:00 Process of ATLAS Inner Tracker Strip Module Production

The Inner Tracker (ITk) for ATLAS Phase-II Upgrade is proposed for the challenge of High Luminosity LHC (HL-LHC), which requests higher radiation resistant, smaller granularity and faster detector. The inner tracker consists of several layers of silicon detectors. This presentation will focus on the recent process of barrel strip module production performed by the ITk strips community, especially the China ITk cooperation group.

Speaker: Ms Yuzhen Yang (高能所)

Slides ITkStripModuleProcess_yuzhen.pdf

14:15 R&D on thin gap RPC for the ATLAS Phase-II upgrade

The ATLAS Muon spectrometer will be significantly upgraded during the Phase-II upgrade in order to cope with the High Luminosity Large Hadron Collider (HL-LHC). Additional RPC detectors will be installed in the inner barrel layer to increase the acceptance and redundancy, especially under the decreased efficiency of the current RPCs which will exceed their designed longevity then. The new RPC layers are required to have increased rate capability and longevity together with improved performances to meet the severe work conditions under HL-LHC. R&D work has been carried out at USTC on the thin gap RPC. By reducing the thickness of the gas gaps and of the resistive electrodes, the rate, longevity and time resolution can be improved. The readout panel and method have to be optimized accordingly to match the new gas gap configuration and to improve the spatial resolution. The usage of a much more sensitive Front End Electronics (FEE) will introduce the challenge to the signal-to-noise ratio, the signal induction and propagation process. In this presentation, the simulation results on the RPC gas amplification procedure and the signal response and propagation process will be reported. These work are very helpful to optimize the RPC work condition and detector design. Some RPC prototypes have been built and tested. The test results will also be presented and discussed.

Speaker: Prof. Yongjie Sun (USTC)

Slides R&D_on_thin_gap_RPC_for_ATLAS_Phase-II_upgrade-Yongjie_Sun.pptx

14:30 Progress of CMS HGCAL

This talk will present recent progress on the CMS Phase-2 endocap calorimeter upgrade (HGCAL) project, with a major focus on the activities and plans of the IHEP HGCAL team, including preparations of the IHEP-HGCAL module assembly centre and a test stand for HGC modules.

Speaker: Dr Yong Liu (Institute of High Energy Physics)

Slides 2018_1221_CMS-HGCAL_Progress_IHEP_YL.pdf

14:45 Calibration and quality control of the CMS triple-GEM detectors

The CMS Collaboration is preparing to install triple-GEM detectors for muon measurements. In this talk, I will give an overview of the operation of triple-GEM detectors, an overview of the data acquisition system that the CMS Collaboration has developed for the triple-GEM detectors, and an overview of the sequence of quality control tests that are performed. I will then report in detail on the status of the latest version of the front-end ASIC, called VFAT3, and the various calibration scans that we are performing on it. The VFAT3 was designed with a large number of programmable registers, which control such things as the voltage threshold for a sending a hit signal. The purpose of the calibration scans is both to program these registers, and also to evaluate the noise on active channels and the rate of channel loss. Finally, I will discuss in detail the hardware and software that is in place for the last stage of the quality control sequence: cosmic ray data taking with full equipped and live detectors.

Speaker: Andrew Levin (Peking University)

Slides AndrewLevin_CLHCP_21Dec2018.pdf

15:00 ALICE ITS upgrade and CCNU effort

A Large Ion Collider Experiment(ALICE) will undergo a major upgrade during the next LHC Long Shutdown (LS2) scheduled in 2019-20 that will allow to study in detail the QGP properties exploiting the increased Pb-Pb luminosity expected during Run 3 and Run 4.The replacement of the existing Inner Tracking System (ITS) with a completely new ultra-light high-resolution detector is one of the cornerstones within this upgrade program. The main motivation of the ITS upgrade is to provide ALICE with an improved tracking capability and impact parameter resolution at very low transverse momentum, as well as to enable a substantial increase of the interaction rate readout. The new ITS will consist of seven layers of an innovative Monolithic Active Pixel Sensors (MAPS) with the innermost layers sitting at only 22 mm from the interaction point. CCNU (Central China Normal University), be a important collaborator in this project. In this talk, we will will not only focus on the physics performance of the new ITS, but also introduce the detector module production and test. The status of the project and CCNU efforts will be presented.

Speaker: Mr Biao Zhang (Central China Normal University)

Slides ALICE_ITS_upgrad__BiaoZhang@4thCLHC.pdf

15:15 Development of the CMS Phase-1 Pixel Online Monitoring System and the Evolution of Pixel Leakage Current

A new pixel online monitoring system has been developed to give a fast and intuitive view of the detector performance both offline and online. The source script was written modularly in Python programming language in association with the SQLite and Java languages. It establishes a connection with the CMS detector monitoring database, and extracts and stores detector information into a local database. Among all of the monitored detector parameters, the pixel leakage current is one of the most interesting, as it reflects the accumulated radiation damage of the silicon sensors. The leakage currents obtained from different module positions in the pixel detector are highly correlated with the distance from the beam pipe. Based on the new monitoring system, we have analyzed the pixel detector leakage current evolution since the recent Phase-I upgrade of the pixel detector and its dependence on the environmental temperature influenced by the cooling loop arrangement inside the pixel detector. The results provide a crucial reference on the detector performance for the re-design of the detector in the Phase-2 upgrade.

Speaker: Fengwangdong Zhang (Peking University)

Slides CLHCP2018.pdf

15:30 Performances of the ATLAS Level-1 Muon barrel trigger during the Run-II data taking

The Level-1 Muon Barrel Trigger is one of the main elements of the event selection of the ATLAS experiment at the Large Hadron Collider. It exploits the Resistive Plate Chambers (RPC) detectors to generate the trigger signal. The RPCs are placed in the barrel region of the ATLAS experiment: they are arranged in three concentric double layers and operate in a strong magnetic toroidal field. RPC detectors cover the pseudo-rapidity range |η|<1.05 for a total surface of more than 4000 m2 and about 3600 gas volumes. The Level-1 Muon Trigger allows to select muon candidates according to their transverse momentum and associates them with the correct bunch-crossing number. The trigger system is able to take a decision within a latency of about 2 μs. The performance of the RPC detector system as well as the Muon Barrel trigger performance during the ATLAS Run-2 data taking are here presented.

Speaker: Marco Sessa (University of Science and Technology of China)

Slides ATLAS_RPC_performance.pdf

15:45 Monolithic CMOS Pixel detectors for future track triggers

Speaker: Mr Jike Wang (EPC)

14:00 → 16:00 Higgs

Convener: Prof. Mingshui CHEN (IHEP)

14:00 Observation of ttH production and multi-lepton analysis at SDU with the ATLAS detector

Speaker: Mr Zhi Li (Shandong University)

Slides Zhi20181222-CLHCP-Updated2.pdf

14:15 Observation of ttH and the multi-lepton analysis with the CMS detector

Latest results of ttH multilepton analysis.

Speaker: ZHANG Huaqiao (IHEP)

Slides ttHobservation@CMS_HuaqiaoZhang.pptx

14:30 Deciphering top-Higgs interaction through multi-top productions at the LHC

I will present talk on the potential of measuring the CP property of Top-Higgs interaction through multiple top-quark production at the LHC.

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

Slides Higgstop_CLHCP18.pdf

14:45 Search for H→bb¯ decays in VBF+gamma final state with the ATLAS detector

This talk will focus the results from searches for the Higgs boson in the bb¯ decay mode in ATLAS experiment, which yields an observed (expected) significance of 5.4 (5.5) standard deviations, thus providing direct observation of the Higgs boson decay into b-quarks. This talk will also highlight the contributions from ATLAS Chinese groups.

Speaker: Prof. Zhijun Liang (IHEP)

Slides zhijun_VBF_hbb_CLHCP2018.pdf

15:00 Observation of H ->bb decays and VH production with the ATLAS detector

A search for the decay of the Standard Model Higgs boson into a bb pair when produced in association with a W or Z boson is performed with the ATLAS detector. The analyzed data, corresponding to an integrated luminosity of 79.8 fb-1, were collected in proton–proton collisions in Run 2 of the Large Hadron Collider at a centre-of-mass energy of 13 TeV. For a Higgs boson mass of 125 GeV, a clear excess of events over the expected background from other Standard Model processes is found . A combination is performed with the results from other searches in Run 1 and in Run 2 for the Higgs boson in the bb decay mode, providing direct observation of the Higgs boson decay into b-quarks. Additionally, a combination of Run 2 results searching for the Higgs boson produced in association with a vector boson provides a direct observation of the Higgs boson being produced in association with a vector boson.

Speaker: Mr Yanhui Ma (School of Physics，Shandong University)

Slides VHbb_20181221.pdf

15:15 Measurement of properties of Higgs boson in four-lepton final state at center-of-mass energy 13TeV of 2017

Standard model (SM) of particle physics successfully explains high-energy experimental data. In 2012, ATLAS and CMS experiments reported the independent observation of a new boson, which is consistent with Higgs boson of SM. Subsequently, study with all Run 1 data shows that the properties of this boson is so far fully compatible with expectations of SM by analyzing various decay channels and production models and combining measurement of ATLAS and CMS experiments. In 2015, LHC started to operate with improved center-mass energy (13TeV). As is expected, LHC may obtain experimental data of 150 fb-1. With updated data, ATLAS and CMS is further making accurate measurement of its properties, which is beneficial to validate or exclude deviations from the standard model and to understand the spontaneous symmetry breaking mechanism of electroweak theory. Properties of Higgs boson are measured in H to ZZ to 4lepton channel using data of proton-proton collisions at a center-of-mass energy of 13TeV collecting integrated luminosity of 41.5fb-1. Results based on 2016 and 2017 are combined and all results are consistent with the expectations of the SM Higgs boson within their uncertainties.

Speaker: Ms Qianying GUO (北京航空航天大学)

Slides CLHCP2018Qianying.pdf

15:30 Latest results on Standard Model Higgs boson in the WW* decay channel using the ATLAS detector

Higgs boson production cross-sections via the gluon-gluon fusion and vector-boson fusion modes are measured in the H→WW*→eνμν decay channel in the ATLAS experiment at the LHC. The H→WW* decay channel has the second largest branching fraction and allows to measure Higgs boson production cross-section with good precision. The analysis based on the proton-proton collision data produced at the LHC at a centre-of-mass energy of 13 TeV and recorded by the ATLAS detector in 2015 and 2016, corresponding to an integrated luminosity of 36.1 fb$^{-1}$ will be presented in this talk. Moreover, future prospectives on the WW channel using the full available data will be discussed.

Speaker: Claudia Bertella (IHEP)

Slides HWW_CLHCP_21122018.pdf

15:45 Measurements of Higgs boson properties in the diphoton decay channel (CMS)

Measurements of Higgs boson properties in the $\mathrm{H}\rightarrow\gamma\gamma$ decay channel are presented. The measurements include Higgs's signal strength relative to the standard model prediction, signal strengths associated with the different Higgs boson production mechanisms, couplings to bosons and fermions, effective couplings to photons and gluons, fiducial cross sections and simplified template cross sections. All results are consistent, within their uncertainties, with the expectations for the Standard Model Higgs boson.

Speaker: Mr Junquan TAO (IHEP/CAS)

Slides 2018CLHCP_CMSHgg_JTao.pdf

14:00 → 16:00 QCD

Convener: Prof. Gang Chen (Physcal Department, China University of Geosciences)

14:00 From Underlying Event Sensitive To Insensitive: Factorization and Resummation

We study the transverse energy spectrum for the Drell-Yan process. The transverse energy is measured within the central region defined by a (pseudo-) rapidity cutoff. Soft-collinear effective theory (SCET) is used to factorize the cross section and resum large logarithms of the rapidity cutoff and ratios of widely separated scales that appear in the fixed order result. We develop a framework which can smoothly interpolate between various regions of the spectrum and eventually match onto the fixed order result. This way a reliable calculation is obtained for the contribution of the initial state radiation to the measurement. By comparing our result for Drell-Yan against Pythia we obtain a simple model that describes the contribution from multiparton interactions (MPI). A model with little or no dependence on the primary process gives results in agreement with the simulation. Based on this observation we propose MPI insensitive measurements. These observables are insensitive to the MPI contributions as implemented in Pythia and we compare against the purely perturbative result obtained with the standard collinear factorization.

Speaker: Daekyoung Kang (Fudan University)

Slides dkang-CLHCP18.pdf

14:15 Electromagnetic transitions of doubly charmed baryons of $J^P=3/2^+$

In 2002 the SELEX experiment collaboration reported the evidence of the doubly charmed baryon $\Xi_{cc}^+(3519)$ in the process of $\Xi_{cc}^+ \to \Lambda_c^+ K^- \pi^+$. Recently, the LHCb collaboration discovered a new state $\Xi^{++}_{cc}(3621)$, which is considered to be a new doubly charmed baryon, in the $\Lambda^+_c K^- \pi^+ \pi^+$ mass spectrum. Many theoretical methods and models, such as the bag model, various quark models, QCD sum rules and lattice QCD, etc, were applied to study these two states and related doubly and triply heavy baryons. The method of light-cone QCD sum rules has been widely applied to study the decay properties of hadrons. In this work, we employ this powerful method to study the electromagnetic transition of the $\Xi^{*++}_{cc}$ into $\Xi^{++}_{cc}\gamma$, whose decay width is estimated to be $13.7~{^{+17.7}_{-~7.9}}$ keV. The results are slightly larger than those obtained using the bag model, but quite comparable with those obtained using some other methods and models. We note that the electromagnetic transition of $\Xi^{*++}_{cc} \to \Xi^{++}_{cc}\gamma$ is probably the main decay mode of the $\Xi^{*++}_{cc}$, and its decay width is large enough for the $\Xi^{*++}_{cc}$ to be observed in the $\Xi^{++}_{cc}\gamma$ channel. We propose to continually search for it in future LHCb and BelleII experiments. Similarly, we have also investigated electromagnetic transitions of some other doubly charmed and bottom baryons, including $\Xi^{*+}_{cc} \rightarrow \Xi^{+}_{cc}\gamma$, $\Omega^{*+}_{cc} \rightarrow \Omega^{+}_{cc}\gamma$, $\Xi^{*0}_{bb} \rightarrow \Xi^{0}_{bb}\gamma$, $\Xi^{*-}_{bb} \rightarrow \Xi^{-}_{bb}\gamma$, and $\Omega^{*-}_{bb} \rightarrow \Omega^{-}_{bb}\gamma$. In the end, we may present our preliminary results of the pion decays of doubly charmed and bottom baryons.

Speaker: Er-Liang Cui (Beihang University)

Slides lcsu_cui_1221.pdf

14:30 $R^4$ corrections to holographic Schwinger effect

We consider $R^4$ corrections to the holographic Schwinger effect in an AdS black hole background and a confining D3-brane background. The potential between a test particle pair are performed for both backgrounds. We find there is no potential barrier in the critical electric field, which means that the system becomes catastrophically unstable. It is shown that for both backgrounds, increasing the inverse 't Hooft coupling parameter $1/\lambda$ enhances the Schwinger effect. We also discuss the possible relation between the Schwinger effect and the viscosity-entropy ratio $ \eta/s $ in strong coupling.

Speaker: 飞 李 (China University of Geosicence (WuHan))

PDF LIFEI-R4-CLHC.pdf

Slides LIFEI-R4-CLHC.ppt

14:45 Production of strange particles in jets and the underlying event in pp collisions at $\sqrt{s}=13$~TeV with ALICE at the LHC

The $p_{\rm T}$ dependence of the baryon-to-meson yield ratio in hadronic and nuclear collisions is sensitive to the collective expansion of the system, the partonic recombination into hadrons, the jet fragmentation and hadronization. In the region $2 < p_{\rm T} < 6 $ GeV/$c$, this ratio for inclusive yields is significantly enhanced at high multiplicity in small collision systems, such as pp and p--Pb collisions, relative to that at lower multiplicity. However, the origin of the enhancement still remains an open question. In this contribution, we explore the connection between the baryon-to-meson ratio enhancement and jet production via the measurement of the $p_{\rm T}$-differential spectrum of strange and multi-strange particles (${\rm K}_{\rm S}^{0}$, $\Lambda$ and $\Xi$) in pp collisions at $\sqrt{s}=13$ TeV, both inclusively and within energetic jets. The results set new constraints on the particle production mechanisms in jets and provide new insight into the understanding of the origin of flow-like correlations observed in small systems.

Speaker: Pengyao Cui (Central China Normal University)

Slides StrangenessInJet_PengyaoCui.pdf

15:00 Excitation functions of kinetic freeze-out temperature and transverse flow velocity in proton-proton collisions

Transverse momentum spectra of negative and positive pions produced at mid-(pseudo)rapidity in inelastic or non-single-diffractive proton-proton ($pp$) collisions over a center-of-mass energy, $\sqrt{s}$, range from a few GeV to above 10 TeV are analyzed by the blast-wave model with Boltzmann-Gibbs (Tsallis) statistics. The model results are well fitting to the experimental data measured by the NA61/SHINE, PHENIX, STAR, ALICE, and CMS Collaborations. In a particular superposition with Hagedorn function, both excitation functions of kinetic freeze-out temperature ($T_0$) of emission source and transverse flow velocity ($\beta_T$) of produced particles obtained from a given selection in the blast-wave model with Boltzmann-Gibbs statistics have a hill at $\sqrt{s}\approx10$ GeV, a drop at dozens of GeV, and then an increase from dozes of GeV to above 10 TeV. Nevertheless, both excitation functions of $T_0$ and $\beta_T$ obtained in the blast-wave model with Tsallis statistics do not show such a complex structure, but a very low hill. In another selection for the parameters or in the superposition with the usual step function, $T_0$ and $\beta_T$ increase slightly from a few GeV to above 10 TeV.

Speaker: Ms lili li (Shanxi University)

Slides 5_2018CLHCP.pdf

15:15 Measurements of charmonium production in p+p collisions at STAR

Charmonia are bound states of charm and anti-charm quarks which provide a unique opportunity to explore properties of the quantum chromodynamics. The production mechanism of charmonia in elementary collisions is not fully understood yet. Several models have been proposed to describe the production of $J/\psi$ mesons, each one employing a different treatment of the hadronization process. Experimental data on the $J/\psi$ cross-section and polarization in p+p collisions can be used to test these models and provide insight into the $J/\psi$ production mechanism. The STAR experiment has recorded large samples of p+p collisions at $\sqrt{s}$ = 200 GeV and 500 GeV. In this talk, we will present recent measurements of $J/\psi$ production cross-section over broad $p_{T}$ ranges. $J/\psi$ polarization measurements in both helicity and Collins-soper frames will also be presented. The results are compared with model calculations, and physics implications will be discussed.

Speaker: Zhen LIU (University of Science and Technology of China)

Slides 6CLHCP2018_ZhenLiu.pdf

15:30 Quarkonium production as a function of charged particles multiplicity in pp collisions measured by ALICE at the LHC

In pp collisions at LHC energies, the production of heavy quarks proceeds dominantly from the hard scattering of two gluons. These quarks then hadronise in either open heavy-flavor hadrons or quarkonia (e.g. J/𝜓, Υ). The study of quarkonium production as a function of the charged-particle multiplicity, therefore, naturally links soft and hard processes that occur in the collision and allows one to study their interplay. While a linear increase of quarkonium production as a function of the charged-particle multiplicity can be reasonably well understood in the context of multi-parton interactions, the observation of deviations with respect to a linear increase requires a more detailed description of the collision and the inclusion of additional mechanisms such as collective effects, color reconnection or percolation. In this contribution, we will present the production of quarkonia as a function of the charged-particle multiplicity measured by ALICE in pp collisions at 𝑠√=13~TeV. These results will be compared to corresponding measurements performed for D mesons, as well as to model calculations.

Speaker: Ms Yanchun Ding (CCNU)

Slides Yanchun_Ding.pdf

15:45 New insights of soft hadron production in pp and pPb collisions at LHC

We find an important new feature of soft hadron production in pp and pPb collisions at LHC energies, that is, the possible transition of hadronization mechanism from the traditional fragmentation to the quark combination. We observe that the ALICE data for the low p_T (<=6GeV/c) spectra of Omega(sss) and phi(s\bar{s}) in pPb collisions at 5.02 TeV exhibit a constituent quark number scaling property. The preliminary of data in high multiplicity events in pp collisions at 7 TeV and those in minimum bias events in pp collisions at 13 TeV also exhibit such scaling property. This is a direct signal/evidence for the quark combination mechanism at hadronization in these small systems created in pp and pPb collisions at LHC energies. We use a quark combination model with equal velocity combination approximation to successfully describe the yields and p_T spectra of various identified hadrons (such as phi, K*, p, Lambda, Xi, Omega, etc) in pp and pPb collisions at LHC energies. In addition, the combination of charm quark with light flavor quarks can well describe the data of p_T spectra of single-charm hadrons D, Ds, Lambda_c in pp and pPb collisions. These results suggest that the constituent quark degrees of freedom play an important role in soft hadron production at hadronization in small systems created in pp and pPb collisions at LHC energies.

Speaker: Dr Jun Song (Jining university)

Slides sj_CLHCP_2018.pdf

16:00 → 16:15 Tea Break

16:15 → 17:45 Detector performance and upgrade

Convener: Jun Guo (S)

16:15 Design and Characterization of MIC4, the Monolithic Active Pixel Sensor for CEPC Vertex Detector

The Circular Electron Positron Collider (CEPC) is proposed as a Higgs factory to produce adequate events, which is the basis for high precision measurement of Higgs boson. The vertex detector in CEPC should meet the requirement of low material budget, high spatial resolution, fast readout speed and low power consumption. The MIC4 sensor is a CMOS Monolithic Active Pixel Sensor (MAPS) being developed for the R&D activities of CEPC vertex detector. It has been implemented in the TowerJazz 180 nm CMOS Image Sensor (CIS) Process with a high-resistivity epitaxial layer. It measures 3.1 mm * 4.6 mm and features a 128 * 64 (column * row) pixel array with a small pixel pitch of 25 μm. A binary front-end circuit has been designed for a compact pixel combined with a sparisified readout circuitry. Each pixel is composed of an amplification, shaping, discrimination circuit and digital logic. To meet the requirement of high spatial resolution and fast readout speed, a new architecture of an asynchronous zero-suppression data-driven readout circuit is proposed and implemented in MIC4 chip. The periphery of the chip contains bandgap, DACs, serializer and LVDS providing bias for the front-end circuit and transmitting the address data of hit pixels off chip. The preliminary tests show that all the blocks of the chip are functional. The front-end features a peaking time of below 1 μs, a duration time of less than 3 μs, a charge threshold of about 223 e- and an Equivalent Noise Charge (ENC) of 6.2e-. Further tests on the mismatch of the pixel and the high speed readout link are under preparation and we will get the conclusion soon.

Speaker: Dr Ping Yang (Central China Normal University)

Slides 1_Design_and_Characterization_of_MIC4,_the_Monolithic_Active_Pixel_Sensor_for_the_CEPC_Vertex_Detector_20181220.pptx

16:30 DESY test beam facilities for HEP detector R&D

Speaker: Mr Yi LIU (IHEP)

Slides testbeam_talk_yi_desy.pdf

16:45 Progress and Status of CMS Trigger Upgrade

Speaker: Prof. Zhen An LIU Zhenan (IHEP)

Slides 3.CMSL1Trigger-CLHC2018.pdf

17:00 Study of damages induced on ATLAS silicon by fast extracted and intense proton beam irradiation

The ATLAS silicon tracker detectors are designed to sustain high dose integrated over several years of operation. This very substantial radiation hardness should also favour the survival of the detector in case of accidental beam losses. An experiment performed in 2006 showed that ATLAS pixel detector modules (silicon planar hybridly coupled with FE-I3 electronics) could survive to beam losses up 1.5 10^10 protons/cm2 in a single bunch with minimal or no deterioration of performance. The upgrade of LHC to even higher luminosity (HL-LHC) calls for a new test of these properties. Two test beam campaigns have been done in 2017 and 2018 at the High-Radiation to Materials (HiRadMat) Facility of the CERN Super Proton Synchrotron in order to establish for the first time the damage threshold of different types of ATLAS IBL pixel and ITK strip detectors under very intense proton beam irradiation.

Speaker: Claudia Bertella (IHEP)

Slides HiradMatReport_CLHC2018_21122018.pdf

17:15 Design of the LHCb Sci-Fi tracker read-out electronics and the QA system

There will be 524,000 channels of SiPM to be readout in the LHCb SciFi tracker, with the 64-ch PACIFIC ASIC. The frontend electronics should have 4 ASICs on each board, with SLVS differential outputs of 256-ch readout signals from the SiPMs of the SciFi. The frontend board (Carrier Board) was designed and evaluated its performance with test beam in 2018 by Tsinghua group. The board was designed as a 14-layers board, with 1.7 mm thickness, TU-862HF halogen-free material and the routing length match of SLVS differential outputs of 256-ch signals was controlled to be less than 3 mm. The first batch of 250 boards has been produced and delivered to CERN to assemble the first C-Frame of the SciFi tracker (SciFi milestone of 2018). Besides, a quality assurance (QA) system for both the PACIFIC ASIC and the frontend board of SciFi tracker was developed. The QA system consists mainly of a PACIFIC readout board, a socket board, an adapter board and a charge injection board. An Altera Cyclone V FPGA is deposited for the readout board, with the firmware to realize the function of clock generation, ASIC configuration, data process, sensor readout, and so on. In 2018.06, we delivered 3 QA systems to Heidelberg university, and the first batch of 1420 ASICs have been tested in June, 2018, and the test result was part of the evaluation of the SciFi electronics and would be very helpful for future classification of mass-produced ASIC in near future.

Speaker: Mr Yuyue Gan (Tsinghua University)

Slides 20181221_CLHC_report_v3.2_AGain.pdf

17:30 The test of the SciFi Tracker electronics for LHCb upgrade

The LHCb Upgrade will replace the electronics of all subdetectors to cope with a hardware triggerless readout at 40 MHz. For the tracker system, the current T1-T3 stations will be fully replaced by the SciFi tracker system based on the scintillating fibre technology. The front-end read-out boards, which are connected to the SiPMs, are co-designed by the Tsinghua and Heidelberg groups. A quality assurance (QA) system is also designed to test the read-out board and the PACIFIC ASICs on the board. This talk will introduce the test flow and the test results of the ASICs and the boards.

Speaker: Mr Li Xu (Tsinghua University)

Slides SciFi_Electronics_QA.pdf

16:15 → 17:45 Future

Convener: Prof. Zuowei Liu (Nanjing University)

16:15 NGI-CHINA and WLCG BEIJING-LCG2 Tire2 report

Speaker: Prof. Xiaofei Yan (IHEP)

Slides BEIJING-LCG2_Tire2_Grid-2018-12-EN-V1.pptx

16:30 Reconstruction and identification of tau leptons decaying hadronically

We present the algorithm developed by the CMS Collaboration in order to reconstruct and identify tau leptons decaying hadronically at 13 TeV, using 2016 data. With respect to the previous result, within several improvements, the algorithm is extended to reconstruct tau leptons in highly Lorentz-boosted pair production.

Speaker: Dr Hongbo LIAO Hongbo (Institute of High Energy Physics)

Slides TAU-16-003.pdf

16:45 Neutrino mass models at LHC upgrades

Speaker: Tong Li (Nankai University)

Slides CLHCP2018_tli.pdf

17:00 On the textures of neutrino mass matrix for maximal atmospheric mixing angle and Dirac CP phase

Speaker: Dr 振华 赵 (辽宁师范大学)

Slides Zhenhua_Zhao.pptx

17:15 Phenomenology for the Simlest Little Higgs Model

Based on the canonically-normalization procedure, we completely derived the interactions in the simplest little Higgs model, and corrected a lot of mistakes in previous papers by others, hence the phenomenology must be fully re-considered. We updated the experimental constraints and collider phenomenology of this model, especially about the pseudoscalar $\eta$, in the narutal region. We concluded that it is very difficult (if not impossible) to test this model at LHC with $\sqrt{s}=13~$TeV, but possible at larger hadron colliders.

Speaker: Ying-nan Mao (NCTS(Hsinchu))

Slides CLHCP4MAO

17:30 The extended Higgs sector: global minimum constraints and measurement at the future electron-positron collider

In this talk, we will discuss the new theoretical constraints, such as the global minimum requirment to the BSM Higgs potential, and the corresponding phenomenology at the LHC searches for the new heavy Higgs boson. With the one-loop BSM correction to the Higgs couplings taken into account, we show that the future electron-positron colliders, such as CEPC, can be complementary to the direct searches for the heavy Higgs bosons, the heavy Higgs boson mass splittings, and the alignment parameters.

Speaker: Prof. Ning Chen (Nankai University)

Slides 6chenning_CLHCP2018.pdf

16:15 → 17:45 Higgs

Convener: Lianliang MA (Shandong University)

16:15 Study on space-time structure of Higgs-jet with the HBT correlation method in e$^+$e$^-$ collision at $\sqrt{s}=250$ GeV

The space-time structure of the Higgs boson decaying into hadron-jets (Higgs-jets) is carefully studied with the HBT correlation method using e$^+$e$^-$ collision events produced by the Monte Carlo generator PYTHIA 8.219 at $\sqrt{s}=250$ GeV. The measurement of the Higgs boson radius and decay lifetime are derived from the HBT correlation of the final state pions, with an upper bound of $R_H \le 1.03\pm 0.05$ fm and $\tau_H \le (1.29\pm0.15)\times 10^{-7}$ fs. This result is consistent with CMS data.

Speaker: hongge Xu (China University of Geosciences)

Slides xhg-18.12.21.pptx

16:30 Pair Production of Higgs Boson in G2HDM at the LHC

Pair production of Higgs boson at the Large Hadron Collider (LHC) is known to be important for the determination of Higgs boson self-coupling and the probe of new physics beyond the Standard Model (SM), especially the existence of new fundamental scalar boson. In this paper we study in detail the Higgs pair production at the LHC in a well-motivated model, the Gauged Two Higgs Doublet Model (G2HDM) in which the two Higgs doublets are properly embedded into a gauged $SU(2)_H$ and a dark matter candidate emerges naturally due to the gauge symmetry. Besides the deviations of Higgs couplings from the SM predictions, the existence of new scalars could enhance the production cross section of Higgs boson pair at the LHC significantly. However, when we take into account the relic density of dark matter and the null result in its direct search, only moderate enhancement can be maintained. We also comment on the capability of distinguishing the signal of a new generic scalar from the SM at the LHC, assuming the Higgs pair production cross sections are the same.

Speaker: Dr Van Que Tran (Nanjing University)

Slides VQTran_PairH_CLHCP2018.pdf

16:45 Observation of VBF Higgs with the ATLAS detector

Vector Boson Fusion (VBF) is the second largest production of the Higgs and its contribution to the discovery of the Higgs is important. After the discovery of Higgs, Searching for Higgs with different production model is one of the most important topics at the LHC. ATLAS observed around 3 sigma with RUN1 data and achieves the first observation (5 sigma) mostly from Higgs decaying into two photons with RUN2 data. This talk will mostly focus on our study of VBF Higgs in ATLAS including the MVA technologies to improve the sensitivities, estimating the backgrounds, extracting statistical results etc.

Speaker: Prof. Yaquan FANG Yaquan (高能所)

Slides vbfHATLASfang_wuhan_updated3.pdf

17:00 Cross section measurement of the Higgs boson decaying in tau-lepton pair with the ATLAS detector

A measurement of the production cross sections of the Higgs boson in proton–proton collisions is presented in the H → ττ decay channel. The analysis is performed using Run 2 data recorded by the ATLAS experiment during the 2015 and 2016 period at the Large Hadron Collider at a center-of-mass energy of √s= 13 TeV. The H → ττ signal over the expected background processes is established with an observed (expected) significance of 4.4 (4.1) standard deviations. Combining this measurement with the results from Run 1 analysis, the observed (expected) significance amounts to 6.4 (5.4) standard deviations, leading to an observation of Higgs boson decaying int tau-lepton pair. The total cross sections in the H → ττ decay channel will be also presented separately for vector boson fusion production and gluon–gluon fusion production. Results are in agreement with Standard Model expectations.

Speakers: Antonio De Maria (N) , Dr 雷 张 (南京大学)

Slides ATL-COM-PHYS-2018-1709_(2).pdf

17:15 Combined measurements of Higgs boson production and decay with the ATLAS experiment

Speaker: Mr Zirui Wang (Shanghai Jiao Tong University)

Slides wangzr20181221CLHCP.pdf

17:30 Search for doubly charged scalar bosons decaying into same-sign W boson pairs with the ATLAS detector

A search for doubly charged scalar bosons decaying into W boson pairs is presented. It uses a data sample from proton–proton collisions corresponding to an integrated luminosity of 36.1 fb−1 collected by the ATLAS detector at the LHC at a centre-of-mass energy of 13 TeV in 2015 and 2016. This search is guided by a model that includes an extension of the Higgs sector through a scalar triplet, leading to a rich phenomenology that includes doubly charged scalar bosons H ±±. Those bosons are produced in pairs in proton–proton collisions and decay predominantly into electroweak gauge bosons H ±± → W±W± . Experimental signatures with several leptons, missing transverse energy and jets are explored. No significant deviations from to the Standard Model predictions are found. The parameter space of the benchmark model is excluded at 95% confidence level for H ±± bosons with masses between 200 and 220 GeV.

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

Slides CLHCP_2018.pdf

19:00 → 21:00 Banquet

Saturday, 22 December

08:30 → 10:30 Plenary

Convener: Prof. Yajun Mao (Peking University)

08:30 Heavy ion physics theoretical overview

Speaker: Prof. Pengfei Zhuang (Tsinghua University)

Slides 1_CLHCP201812_Zhuang.pptx

08:54 Heavy ion physics experimental overview

to be decided

Speaker: Hua Pei (Central China Normal University)

Slides 2_HuaPei_HeavyIon.pdf

09:18 Heavy flavor physics in heavy ion collisions

Speaker: Yifei Zhang (中国科学技术大学)

Slides HF_CLHCP2018_YF.pdf

09:42 QCD Physics at the LHC

In this talk, I will review the current status of the QCD physics at the LHC, ranging from the precision phenomenologies to the more recent developments in jet substructures. Available theory frameworks for achieving the first principle understanding of the related processes will also be reviewed. Connections to the other aspects of the LHC physics, e.g. LHC new physics searches, may also be discussed.

Speaker: xiaohui liu (beijing normal university)

Slides CLHCP2018-QCD-2.pdf

10:06 CEPC status

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

Slides CEPC-CLHCP4.pdf

10:30 → 11:00 Tea Break

11:00 → 12:30 Plenary

Convener: Prof. Zhengguo Zhao (USTC)

11:00 LHCb Detector Upgrade

Speaker: Dr Ming Zeng (Tsinghua University)

Slides 20181222_CLHC_LHCb_Detector_Upgrade_MingZeng_v1.pdf

11:20 ATLAS Detector Upgrade

Speaker: Dr Hongbo ZHU (IHEP)

Slides ATLAS_Upgrades_CLHCP.pdf

11:40 CMS Detector Upgrade

Speaker: Prof. Yong Ban (Peking University)

Slides banypku

12:00 ALICE Detector Upgrade

Speaker: Prof. Yaping Wang (Central China Normal University)

Slides ALICE_Upgrade_CLHCP2018_YPWang.pdf

12:20 Summary and Closing

12:30 → 14:00 Lunch Break

14:00 → 16:00 Parallel: ALICE Internal Meeting

Convener: Prof. 代翠 周 (Central China Normal University)

14:00 → 16:00 Parallel: ATLAS Internal Meeting

Convener: Prof. Zhengguo Zhao (USTC)

14:00 → 16:00 Parallel: CMS Internal Meeting

Conveners: Prof. Guoming 陈国明 (高能所) , Prof. Yajun Mao (Peking University)

14:00 → 16:00 Parallel: LHCb Internal Meeting

Convener: Prof. Yuanning Gao (Peking University)