765 research outputs found
Search for Beyond Standard Model (BSM) Higgs bosons in final states with bottom quarks with the full Run 2 CMS dataset
This poster is dedicated to searches for additional Higgs bosons from an extended Higgs sector in fermionic final states. These scalar states are predicted by several Beyond Standard Model theories, like Two Higgs doublet Models (2HDM) and the Minimal Supersymmetric extension of the Standard Model (MSSM). The results are interpreted in various benchmark scenarios
Search for the lepton-flavor violating decay of the Higgs boson and additional Higgs bosons in the final state at TeV within CMS
The search for lepton-flavor violating decays of the Higgs boson to an electron-muon pair using data from proton-proton collisions at TeV collected by the CMS experiment at the LHC is presented. The dataset corresponds to an integrated luminosity of . No significant excess of events is observed for the 125 GeV Higgs. This analysis leads to the most stringent upper limits at 95\% confidence level so far on the branching fraction of the 125 GeV Higgs boson decaying into an electron and a muon, with an observed (expected) limit of 4.4 (4.7)10.
A search for additional scalar resonances, X, in the same decay channel, leads to upper limits on the cross-section of ppXe in the mass-range of 110-160 GeV. Here, an excess of events is observed at an electron-muon invariant mass of approximately 146 GeV with a local (global) significance of 3.8 (2.8) standard deviations. These results provide valuable insights into lepton-flavor-violating Higgs decays and contribute to our understanding of the Higgs boson sector and potential physics beyond the Standard Model
First alignment of the Run 3 CMS tracker with cosmic rays and collision tracks
After the long shutdown preparing the CMS detector for Run 3, the tracker alignment constants, namely position, orientation, and curvature of each of the modules that compose the tracking system need to be derived again with a high precision in order to ensure a good performance of the detector for physics analysis. This process constitutes a major computational challenge due to the enormous number of degrees of freedom involved. The latest public results of the CMS tracker alignment performance corresponding to the very first alignment with collision data, derived after the work in the underground experimental cavern was finished, will be presented. The workflows, turnarounds, the so-called automated alignment, and the use of CMS CERN Analysis Facilities (CAF) for the derivation of the alignment conditions will also be discussed
Alignment of the CMS tracker system and performance in Run3
The CMS tracker system is a state-of-the-art, fully silicon-based detector that consists of two subsystems: the Pixel and Strip detectors. With a remarkable resolution of less than 10 microns, the tracker is designed to accurately measure the trajectory of charged particles. Prior to the start of the latest data-taking period of the Large Hadron COllider, the innermost sub-detector of the tracker was upgraded to enhance its performance. To fully benefit on the excellent hit resolution and obtain the highest quality physics data, it is neccessary to measure the position and orientation of each module with precision beyond what mechanical alignment can provide (typically 100 microns). Additionally, fluctuations in the operating conditions may cause substructures to shift, needing regular corrections to ensure proper alignment, which are referred to as tracker alignment. This poster aims to present the alignment procedures adopted for the CMS tracker system and evaluate their impact on the overall performance of the detector
Exploring Lepton-Flavor Violation (LFV) in . earch for the LFV decay of the Higgs boson and additional Higgs bosons in the final state
This poster presents a search for lepton-flavor violating decays of the Higgs boson to an electron-muon pair using data from proton-proton collisions at √s = 13 TeV collected by the CMS experiment at the LHC. The dataset corresponds to an integrated luminosity of 138 fb−1. No significant excess of events is observed for the 125 GeV Higgs, leading to the most stringent upper limits so far on the branching fraction B(H → eµ) at 95% confidence level, with an observed (expected) limit of 4.4 (4.7) × 10−5. Upper limits on the cross-section of pp->X->eµ are set on the mass-range of X of 110-160 GeV. Here, an excess of events is observed at an electron-muon invariant mass of approximately 146 GeV with a local (global) significance of 3.8 (2.8) standard deviations. These results provide valuable insights into lepton-flavor violating Higgs decays and contribute to our understanding of the Higgs sector and potential new physics beyond the Standard Model
Performance of the CMS Tracker during Run 3
The current CMS silicon tracker consists of two tracking devices: the inner pixel and the outer strip detectors. The tracker occupies the region around the center of CMS, where the LHC beams collide, and therefore, operates in a high-occupancy and high-radiation environment produced by the particle collisions within the LHC tunnel. \\
This article provides an overview of the excellent performance of the CMS silicon tracker during the ongoing Run 3 data-taking period. It discusses the behavior of local observables, such as hit reconstruction efficiency, their response to the accumulated integrated luminosity, and the precision achieved in aligning the detector components
Searches for additional heavy Higgs Bosons - Overview of Run2 analyses inspired by models involving an extended Higgs sector
Extensions of the Standard Model Higgs sector with a second Higgs doublet allow for the existence of charged Higgs bosons as well as heavy pseudoscalar Higgs bosons. The heavy pseudoscalars can decay into a Z boson and a lighter scalar Higgs boson, which could be either the established 125 GeV state, or a new heavier sibling. Charged Higgs bosons are probed in various final states, including decays to a W boson and another lighter scalar. This presentation discusses recent results from the CMS experiment based on the Run 2 dataset.Since the discovery of the Higgs boson in 2012 by the ATLAS and CMS experiments, investigating the detailed structure of the Higgs Sector is of highest importance. Models featuring two complex Higgs doublets, like generic two-Higgs-doublet models (2HDM) or models with additional singlets (2HDM+S) offer a rich phenomenology including additional neutral Higgs states. This talk will include results on searches for single heavy Higgs bosons in different final states, including ditau, WW, and diphoton final states. This presentation will report on recent results of the CMS experiment in this field, based on the data collected in LHC Run 2
CMS tracker performance in Run3
The CMS silicon tracker consists of two tracking devices: the inner pixel and the outer strip detectors. The tracker occupies the region around the center of CMS, where the LHC beams collide, and therefore, operates in a high-occupancy and high-radiation environment produced by the particle collisions within the LHC tunnel.This poster summarizes the tracker performance during the ongoing Run 3 data-taking period. The operational challenges influencing the active fraction and read-out efficiency, the behaviour of local observables such as the hit reconstruction efficiency, as well as the radiation effects given the accumulated integrated luminosity are discussed
Search for additional MSSM/2HDM H→bb with Run 2 CMS data
Some Beyond Standard Model (BSM) theories, like the Minimal Supersymmetric extension of the Standard Model (MSSM) or the Two-Higgs Doublet Model (2HDM), predict the existence of additional Higgs bosons with an enhanced coupling to bottom quarks. This talk focuses on the search for new neutral Higgs bosons decaying into b-quarks and produced in association with at least one b-quark. The analyzed data were collected by the CMS experiment at a centre-of-mass energy of 13 TeV, with the latest data reprocessing. First limits on the MSSM H->bb process using these data are shown
- …