New physics beyond the Standard Model could well preferentially show up at the LHC in final states with taus. The development of efficient and accurate reconstruction and identification of taus is therefore an important item in the CMS physics programme. The potentially superior performance of a particle-flow approach can help to achieve this goal with the CMS detector. Preliminary strategies are presented in this summary for the hadronic decays of the taus.
Search for the direct production of charginos, neutralinos and staus in final states with at least two hadronically decaying taus and missing transverse momentum in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
Evidence is presented for standard model production of a Z boson in association with a single top quark. The analysis uses a data sample of proton-proton collisions at $\sqrt{s} = 13$ TeV recorded in 2016 by the CMS detector, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Final states containing three leptons (electrons or muons) and at least two jets are investigated, and the measured cross section is $σ($pp $\rightarrow$ tZq $\rightarrow $Wb$\ell^{+}\ell^{-}$q) = 123$^{+44}_{-39}$ fb, where $\ell$ stands for electrons, muons or taus. The corresponding observed (expected) signif…
The classic searches for supersymmetry have not given any strong indication for new physics. Therefore CMS is designing dedicated searches to target the more difficult and specific supersymmetry scenarios. This contribution present three such recent searches based on 13 TeV proton-proton collisions recorded with the CMS detector in 2016, 2017 and 2018: a search for heavy gluinos cascading via heavy next-to-lightest neutralino in final states with boosted Z bosons and missing transverse momentum; a search for compressed supersymmetry in final states with soft taus; and a search for compressed, …
These proceedings summarize the results of four analyses which searched for squarks and gluinos in hadronic final states with missing transverse momentum in 2.3 fb$^{-1}$ of data in proton-proton collisions at $\sqrt{s}=13$ TeV collected in the year 2015 with the CMS detector at the CERN LHC. Each analysis is characterized by a different kinematic variable that is sensitive to the presence of invisible particles, e.g., $M_\text{T2}$, $α_{\text{T}}$, and razor variables. We observed no significant deviation from the standard model prediction and placed limits on the production cross sections an…
Measurements of the hadronic activity and the electroweak production in events with a Z boson and two jets in proton-proton collisions with the CMS experiment
本文介绍了在CERN大型强子对撞机上利用CMS实验观测到的$\sqrt{s} = 8$ TeV pp碰撞中两喷流产生Z玻色子的电弱过程，所用数据样本的积分亮度为19.7 fb $^{-1}$ .结合μ子和电子通道的截面测量与理论预期一致。还测量了选定的Z+两个喷注事件的辐射图，以及喷注之间快度区间的强子活动。这些结果是相当重要的矢量玻色子融合过程的更一般的研究，相关的希格斯玻色子搜索和测量的电弱规范耦合和矢量玻色子散射。
The results from a search for chargino-neutralino or chargino pair production via electroweak interactions are summarized. The results are based on a sample of $\sqrt{s}=13~\mathrm{TeV}$ proton-proton collisions from the LHC, recorded with the CMS detector~\cite{cms} and corresponding to an integrated luminosity of $137~\mathrm{fb}^{-1}$. The search considers final states with large missing transverse momentum and pairs of hadronically decaying bosons WW, WZ, and WH, which are identified using novel algorithms. No significant excess of events is observed relative to the expectation from the st…
This article summarises three searches for diboson resonances in the all-hadronic final state using data collected at a center-of-mass energy of $\sqrt{\rm{s}}=13$ TeV with the CMS experiment at the CERN LHC. The boson decay products are contained in one large-radius jet, resulting in dijet final states which are resolved using jet substructure techniques. The analyses presented use 2.3, 35.9 and 77.3 inverse femtobarns of data collected between 2015 and 2017. These include the first search for diboson resonances using data collected at a 13 TeV collision energy, the introduction of a new algo…
Results from searches for new particles with enhanced couplings to third-generation quarks are presented. They are based on proton-proton collision data at a center-of-mass energy of 13 TeV recorded by the CMS experiment. The signatures include single and pair production of vector-like quarks and heavy resonances decaying to third-generation quarks. A wide range of final states, from multi-leptonic to entirely hadronic is covered. Jet substructure techniques are employed to identify highly boosted heavy standard model particles in their hadronic decay modes.
Search for non-resonant Higgs boson pair production in final states with leptons, taus, and photons in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
The identification of hadronic tau lepton decays is an important requirement for the LHC physics program, both in terms of standard model measurements and the search for beyond-the-standard-model physics. The ATLAS and CMS algorithms for identification and energy calibration of hadronic tau lepton decays are conceptually different. They are described together with measurements of relevant performance figures.
Events containing a pair of high energy hadronic jet can provide clear signatures in the search for new physics at high energy hadron colliders. The ATLAS and CMS experiments collected the data from LHC collisions at $\sqrt{s}$= 13 TeV during 2015 and 2016, looking for evidence of new resonances or deviations from the Standard Model predictions. Althoug no hint of new physics was seen, strong limits have been set on the most interesting benchmark models, improving LHC Run1 reach.
Searches for direct electroweak production of charginos and neutralinos in signatures with two light leptons of the same charge and with three or more leptons including up to two hadronically decaying τ leptons are presented . The full 2016 dataset of pp collisions recorded by CMS at a center-of-mass energy of 13 TeV is used, corresponding to an integrated luminosity of 35.9 /fb. The observed event rates are in agreement with expectations from the standard model. These results probe charginos and neutralinos with masses up to values between 225 and 1150 GeV, depending on the model parameters a…
Many models of physics beyond the Standard Model (SM) contain enhanced couplings to third generation particles. The predicted signatures include vector-like quarks and $t\bar{t}$ resonances. We present a review of non-SUSY based searches for new physics beyond the SM in final states with third-generation quarks using proton-proton collision data collected with the CMS detector at the CERN LHC. We analyze a wide range of final states, from multi-leptonic to entirely hadronic, and many results use novel analysis techniques to identify and reconstruct highly boosted final states that are created …
An overview of the searches for new heavy resonances decaying to standard model (SM) bosons at the TeV mass scale is presented. Results are based on data corresponding to an integrated luminosity up to about $36\; \mathrm{fb}^{-1}$ recorded in proton-proton collisions at $\sqrt{s}=13$ TeV with the CMS detector at the Large Hadron Collider at CERN. The bosons coming from the resonance decay can be W, Z, or the SM Higgs. For very heavy resonances, bosons are produced with momentum considerably higher than their mass, modifying in a very appreciable way the event topology. The quarks originated f…
We present the first results on searches for new massive resonances decaying to a top-antitop quark ($t\bar{t}$) pair with the CMS detector at the LHC in proton-proton collisions with a center of mass energy of $\sqrt{s}=13~\mathrm{TeV}$. The data set considered corresponds to an integrated luminosity of $2.6~\mathrm{fb}^{-1}$ recorded during the the first year of the LHC Run-2. Searches are performed by measuring the invariant mass distribution of the $t\bar{t}$ system in semileptonic and fully-hadronic final states. Dedicated techniques are used to identify the decay of highly-boosted top qu…
A search for production of the supersymmetric partners of the top quark, top squarks, is presented. The search is based on proton-proton collision events containing multiple jets, no leptons, and large transverse momentum imbalance. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of 137 fb$^{-1}$. The targeted signal production scenarios are direct and gluino-mediated top squark production, including scenarios in which the top squark and neutralino masses are nearly degenerate. The search utilizes no…
The LHCb detector provides accurate vertex reconstruction and hadronic particle identification, which make the experiment an ideal place to look for light long-lived particles (LLP) decaying into Standard Model (SM) hadrons. In contrast with the typical search strategy relying on energetic jets and a high multiplicity of tracks from the LLP decay, LHCb can identify LLPs in exclusive, specific hadronic final states. To illustrate the idea, we study the sensitivity of LHCb to an exotic Higgs decay $h\to SS$, followed by the displaced decay of GeV-scale scalars into charged kaons $S\to K^+K^-$. W…
We study the LHC discovery potential in the search for heavy neutral leptons (HNL) with a new signature: a displaced shower in the CMS muon detector, giving rise to a large cluster of hits forming a displaced shower. A new Delphes module is used to model the CMS detector response for such displaced decays. We reinterpret a dedicated CMS search for neutral long-lived particles decaying in the CMS muon endcap detectors for the minimal HNL scenario. We demonstrate that this new strategy is particularly sensitive to active-sterile mixings with $τ$ leptons, due to hadronic $τ$ decays. HNL masses be…
A search for the production of heavy resonances decaying into top quark-antiquark pairs is presented. The analysis is performed in the lepton+jets and fully hadronic channels using data collected in proton-proton collisions at sqrt(s) = 13 TeV using the CMS detector at the LHC, corresponding to an integrated luminosity of 2.6 inverse femtobarns. The selection is optimized for massive resonances, where the top quarks have large Lorentz boosts. No evidence for resonant t t-bar production is found in the data, and upper limits on the production cross section of heavy resonances are set. The exclu…
Electroweak precision physics via angular distributions in hadronic $τ$ decays
Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional（墨西哥国立理工学院高级研究中心）；Instituto de Física Corpuscular (IFIC), CSIC‐Universitat de València（瓦伦西亚大学-西班牙国家研究委员会粒子物理研究所）；Indiana University（印第安纳大学）；Universidad de Castilla-La Mancha（卡斯蒂利亚-拉曼恰大学）
