Contribution of support tube (light grey), beam tube (dark grey) and sub-detectors: TOB (red, outer tracking barrel, 6-layer strip detector), Pixel Phase I (blue), TEC (yellow, Tracker Endcap) and TID+TIB (magenta, Tracker Inner Disks + Tracker Inner Barrel) are stacked [21]. Front electronics locations for HB and HE calorimeters are indicated by "FEE". The depth segmentation of the HB and HE detectors is also shown.
The SM Higgs mechanism
Contribution of support tube (light grey), beam tube (dark grey) and sub-detectors: TOB (red, outer tracking barrel, 6-layer strip detector), Pixel Phase I (blue), TEC (yellow, Tracker Endcap) and TID+TIB (magenta, Tracker Inner Disks + Tracker Inner Barrel) are stacked [21]. The ¯ j10 particle is called “LLP” since it is the only long-lived particle in the signal model considered.
Searches for physics beyond the Standard Model at the LHC
Hierarchy problem and supersymmetry (SUSY)
As the energy scale of the virtual particles increases, the quantum fluctuations become larger and the mass of the Higgs boson becomes heavier. 2.1) Radiation corrections are proportional to the energy scale of virtual particles, which can be written as ⇤.
The minimal supersymmetric extension of the Standard Model (MSSM) 8
In the MSSM, the Higgsino is a neutral, spin-1/2 particle that is a supersymmetric partner of the Higgs boson. In the MSSM, the gravitino is the superpartner of the graviton, which mediates the force of gravity.
The mass-degenerated GMSB models
40 GeV. Triggers require events to have at least two photons, with the leading photon having a transverse energy ⇢) > 30 GeV and the trailing photon having ⇢) > 18 (22) GeV for the data acquisition period. Low High Low High weight / (fstat). the parameters of each double crystal ball function remain constant.
The Compact Muon Solenoid
The superconducting solenoid
The main role of the yoke is to increase the homogeneity of the field in the tracer volume and to return the magnetic flux of the solenoid to reduce the scattered field. The steel plates act as an absorber for the four muon stations (interlocking layers) of the muon chambers, which measure the muon quantity independently of the internal tracking system.
The inner tracker
One quadrant of the detector is shown, the lag radii and disk positions are given relative to the interaction point (IP). The performance of the phase 0 pixel detector is only slightly degraded at 1⇥1034 2< 2B 1 (25 ns crossing time), but degrades rapidly with higher pileup, losing efficiency as well as suffering from more spurious traces.
The electromagnetic calorimeter (ECAL)
The graph compares the resolution achieved after a refined calibration of the data collected at 13 TeV during Run 2 in and 2018. A stable ECAL energy resolution is observed over the course of Run 2, despite the increased LHC brightness and the aging of the detector [32 ].
The hadron calorimeter (HCAL)
The locations of the front-end electronics for the HB and HE calorimeters are indicated by . It is clear that the resolution of the reconstructed muon peak is significantly improved due to the improved readout.
The muon system
It was found that the dependence on the muon moment is negligible in the range of the selected muon sample. The locations of the various muon stations and the reflow steel disks are shown (dark areas).
The CMS trigger and data acquisition system (TriDAS)
The architecture of the CMS Level-1 trigger system is shown in Figure 4.22, which includes local, regional, and global components. The HLT menu processing time distribution and the typical average timing per event of the HLT tasks running on the HLT farm as a function of instantaneous brightness, when recording data in 2016, are shown in Figure 4.24. The final trigger decision is the logical OR of the decisions of the individual paths.
The Worldwide LHC Computing Grid (WLCG)
The Tier-0 farm performs the first event reconstruction and writes RECO events of 0.25 MB. RAW and RECO versions of each primary data set are archived on the Tier-0 Mass Storage System (MSS) and transferred to at least one Tier-1 center. Therefore, RAW and RECO data are available either in the Tier-0 archive or at a minimum of one Tier-1 center.
Introduction
The combination also fills some intermediate gaps in the mass coverage of the individual assays. This variable is defined as the sum of the transverse moment of all tracks in the jet cone, i.e., Õ. trk2jet?). The predictions for the shape and normality of the [distribution are consistent with the data.
We provided a comprehensive overview of the Large Hadron Collider (LHC) and the Compact Muon Solenoid (CMS).
Event samples
Event reconstruction and selection
Analysis strategy
The SM Higgs boson background, on the other hand, shows a resonant shape in the diphoton mass spectrum, which is constrained to within the uncertainties of the MC simulation predictions. Events in the Hb1¯ and Zb1¯ categories are further divided into high ?T and low ?T subcategories using the same criteria as above. iv) Among the remaining events, those with a Higgs boson candidate ?Tof greater than 110 GeV are classified as “High-?T”. v) Finally, the remaining events are categorized as “high resolution” or “low resolution”. If f
Background estimation
The normalization for the SM Higgs background is limited to the best estimate from the Monte Carlo simulation prediction to within systematic uncertainties. Nuisance parameters, modeled as log-normal distributions, which take into account the systematic uncertainties on the SM Higgs background normalization due to missing higher-order corrections, PDFs, trigger and selection efficiencies, beam energy scaling uncertainties and b-marking efficiencies are included in the model for the SM Higgs background as well as the signal. Finally, \` is the nuisance parameter for the scale uncertainty for the signal and SM higgs line shape and^` is the magnitude of the scale uncertainty.
Systematic uncertainties
The bins of the search region shown correspond to the Muon Low-?T category, bin 2, of the EWP analyses. For the above two scenarios, the mass of chargin and the next lightest neutral is 175 GeV. Exclusion limits for production models ej10ej10 are presented in The term "trackless" refers to the low track multiplicity of jets produced by LLP decay occurring in the calorimeters or in the last few layers of the silicon tracker, as opposed to prompt jets originating directly from the primary impact point. A dedicated TD jettagger is used in this work to improve the sensitivity to LLPs with masses as small as 127 GeV by taking advantage of the time delay and traceless features of the jet signature. Signal events typically exhibit large lack of transverse momentum due to the momentum of gravitinos that do not interact with the detector. The signal sample events can be reweighted to simulate any value of decay branching ratios ej10. For all samples, the detector response is simulated using a detailed description of the CMS detector based on G 4 [155]. Thus, the event distribution is simply the product of two LLP decomposition probabilities: The variable is defined as the ratio of the maximum ?) tracks in the jet cone associated with the primary peak to the energy of the hadrons in the jet. This variable is defined as the sum of the transverse moments of all the tracks in the jet cone that are connected to the primary tip, i.e. Õ. In fig. We also subtract the electron ?) from the variable consists of the sum of all traces contained in the jet cone including Umax(3) and CA02:29 4C?). The smearing procedure is also applied to the variables of neutral hadron energy fraction (20), ECAL rec shock multiplicity (13), ECAL rec shock energy fraction (14), fragmentation function (18). Event selection Electron energy fraction: is the ratio of the energy sum of the electrons collected in the jet divided by the raw energy of the jet. Photon energy fraction: is the ratio of the energy sum of the photons collected in the jet divided by the energy of the raw jet. The final cold mass design of the CMS solenoid.” In: 16th International Conference on Magnetic Technology (MT-16). Supergauge invariant extension of the Higgs mechanism and a model for the electron and its neutrino”. Measurement of the top quark pair production cross section with ATLAS in pp collisions at p. Background estimation The dominant uncertainty in the background estimate is related to the misidentified TD beam background, which includes contributions from the CR sample size, the nbkg process dependence, and the validity of the matrix method, which are 4%, 30%, and 13%, respectively. respectively compared to the total background prediction. For signal yield prediction, the largest uncertainty arises from the efficiency of the TD jet tagger, which includes a component of the jet time correction uncertainty, as well as a component estimated using the methods discussed in Section 7.5, and amounts to a maximum of 29% compared to the signal yield, depending on the signal model parameters. Uncertainties associated with PDFs regarding beam energy scale and resolution, missing higher order QCD corrections, stack modeling, simulation sample size, and lepton and photon veto efficiency are also considered and their impact is summarized in Table 7.7. No background prediction is shown for the bin with zero TD-labeled jets, as this is the main control region used to predict the background for the remaining two bins. We derive upper bounds at a 95% confidence level (CL) for the product of the production cross section of the neutralino pair (fej0. 1ej10) and the relevant branching fraction using the modified frequentist CLscriterion [117,118] and an asymptotic formula [116] . The upper limits are relatively independent of the branching fraction B(ej10! ⌧˜), which varies by less than 10% over the entire range. The CMS detector, on the other hand, is a more advanced detector designed specifically to study the products of proton-proton collisions at the LHC. TheC0E4A064 combines the measurements of the two SiPMs and improves the timing resolution by about pp. The particle flow ignition path is a new and central design feature of the Stage II L1 trigger system. The MTD design The BTL will be built with LYSO:Ce scintillation crystals (cerium-doped lutetium-yttrium orthosilicate ((Lu1 GYG)2SiO5:Ce)) and silicon photomultipliers (SiPMs) that meet the operational requirements of the HL-LHC. At each end of the rod is a readout channel that measures the arrival time of the MIP. Each TOFHIR provides precise timing information for 32 SiPMs based on leading edge (LE) discrimination of their pulses, followed by time-to-digital converter (TDC) measurement. Measurement of the resolution of the track impact parameters with the ATLAS experiment at LHC using data from 2016-2018”. Carrying out photon reconstruction and identification with the CMS detector in proton-proton collisions atp. Searching for long-lived particles decaying in the CMS end-cap muon detectors in proton-proton collisions atp. The Timing Level-1 Trigger at the HL-LHCIntroduction
Event samples
Event reconstruction
DNN tagger
Systematic uncertainties
Results
Summary
The Barrel Timing Layer (BTL)
Test beam results
