Harvesting of the large 13 TeV data set delivered by the LHC in 2016 and collected with the CMS detector continues, with 20 new results to be presented at the EPS 2017 conference, adding to the more than 60 results already presented at the 2017 Moriond and LHCP conferences, most of which use the full 2016 luminosity. These new results range from the observation of Higgs boson decays to tau leptons, to a precise scrutiny of the Standard Model (SM), and to searches for new phenomena such as supersymmetry.
Following the evidence for H→ττ decays obtained using the 2016 data, presented at the LHCP conference in May, CMS now has the first observation of this decay by a single experiment. The combination of the 13 TeV results with the corresponding results previously obtained at 7 and 8 TeV leads to an observed significance of 5.9 standard deviations, equal to the expected significance. This is of paramount importance to establishing the coupling of the Higgs boson to leptons and represents an important step towards measuring its couplings to third generation fermions.
The precision tests of the SM include a new measurement of the effective weak mixing angle, using the forward-backward lepton asymmetry in Drell-Yan production, based on data collected at 8 TeV. The measured value of sin2θefflep = 0.23101 ± 0.00052 is currently the best measurement of this important SM parameter from the LHC and is competitive with previous measurements performed at the Tevatron. The large data sample to be delivered by the LHC in Run 2 will allow us to further improve this measurement.
Finally, CMS has also released more than 10 direct searches for new physics using the full 2016 data sample. The CMS-TOTEM Precision Proton Spectrometer, which started its operation in 2016, has obtained the first evidence for the central semi-exclusive production of dimuon pairs, pp → p μ+μ− p(∗), with mass m(μμ) > 110 GeV, from 10 fb-1 of data collected during the regular high-intensity runs of the LHC. This process is sensitive to new-physics contributions and has never before been measured. The search for the production of a pair of Higgs bosons in the bbγγ final state, sensitive to the Higgs self-coupling, provides the most stringent constraint on the product of the production cross section and branching fraction. The high luminosity LHC will provide valuable data to finally probe this fundamental parameter of the Higgs mechanism. New results in searches for exotic phenomena include more stringent constraints on Dark Matter mediators, excited states of light- and heavy-flavor quarks, extra dimensions, heavy vector-like quarks, long-lived particles, and the direct production of tau sleptons, as well as the electroweak production of charginos and neutralinos.
List of New Results from CMS for the EPS 2017 Conference
- SMP-16-007: Measurement of the weak mixing angle with the forward-backward asymmetry of Drell-Yan events at 8 TeV
- SMP-16-010: Measurement of the differential jet production cross section with respect to jet mass and transverse momentum in dijet events at 13 TeV
- TOP-16-014: Measurement of the differential cross sections of top quark pair production as a function of kinematic event variables at 13 TeV
- HIG-17-008: Search for Higgs boson pair production in the final state containing two photons and two bottom quarks at 13 TeV
- HIG-16-043: Observation of the SM scalar boson decaying to a pair of τ leptons with the CMS experiment at the LHC
- HIG-16-021: Higgs to WW measurements at 13 TeV with 2015 and 2016 data
- SUS-16-052: Search for supersymmetry in events with at least one soft lepton, low jet multiplicity, and missing transverse momentum at 13 TeV
- SUS-17-004: Search for electroweak production of charginos and neutralinos at 13 TeV
- SUS-17-003: Search for pair production of tau sleptons in all-hadronic final state
- EXO-17-002: Search for excited states of light and heavy flavor quarks in the γ + jet final state at 13 TeV
- EXO-16-046: Search for new physics with dijet angular distributions in proton-proton collisions at 13 TeV and constraints on dark matter and other models
- EXO-16-051: Search for dark matter in final states with a top quark and missing transverse momentum using new hadronic top quark tagging techniques
- EXO-17-004: Search for long-lived particles that stop in the CMS detector and decay to muons
- B2G-17-009: Search for a singly produced vector-like quark B decaying to a b quark and a Higgs boson in a fully hadronic final state using boosted topologies
- B2G-17-005: Search for heavy resonances decaying into a Z boson and a vector boson in the νν qq ̄ final state
- B2G-16-025: Search for pair production of excited top quarks in the lepton+jets final state
- PPS-17-001: Evidence for proton-tagged, central semi-exclusive production of high-mass muon pairs at 13 TeV with the CMS-TOTEM Precision Proton Spectrometer
- FTR-16-002: Projected performance of Higgs analyses at the HL-LHC for ECFA 2016