Highlights from the CMS Experiment
Sergei Shmatov (JINR, Dubna)
for the CMS Collaboration

https://cms.cern/

The 20th Lomonosov Conference on Elementary Particle Physics
Moscow State University, Moscow, 22 August, 2021

Outline❑ LS2 Status and Phase 2 Upgrade❑ Highlights from Physics results✓ Standard Model✓ Higgs Physics✓ Searches for New Physics

1058 papers based oncollision data(+25 on cosmic data)… 12 CMS talks at the ConferenceStandard Model and Higgs
H. Liao, Top quark physics at CMS
A. Lanev, Electroweak measurements at CMS
O. Kodolova, Results on QCD physics at CMS
A. Tulupov, B physics results from CMS
G. Mitselmakher, H(125) measurements at CMS
BSM
A. Kaur, Exotic physics signatures at CMS
M. Savina, Dark Matter searches at CMS
G. Kole, Searches for additional Higgs bosons at CMS
E. Lipka, Towards new physics through precision
J. Babbar, Search for New Resonance in Photon andJet final State using CMS Data

Heavy Ions
S. Petrushanko, Heavy-ion physics at CMS
Highlights from the CMS Experiment

http://cern.ch/cms-results/publicresults/publications-vs-time/
20.08.2021

2LS2 Activities

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CMS Phase 2 UpgradeThis year

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LHC Timeline and Data Taking✓ ~160 fb-1 of proton-proton collisions at 13 TeV delivered
during Run 2✓ Also collected and analyzed Heavy Ion pPb and PbPb collisions(see dedicated report by S. Petrushanko)

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CMS “full Run 2” Performance
Comparison of Z mass resolution
Before and after final calibration
Included in Legacy Run 2 rereco

Performance of the CMS muon trigger system
in proton-proton collisions 13 TeV
JINST 16 (2021) P07001

JINST 16 (2021) P05014

b-jet performance using
Deep Neural Networks

CMS-DP-2020-037

CMS-DP-2021-004

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Summary of Standard Model Tests
W and Z production

High rate at the LHC✓ Provides statistic to study inclusive and differential distributions✓ Good understanding of the detectors allow for precision
measurements✓ Test p-QCD and PDF in different regimes, deviations may indicate
presence of new physics, EFT interpretations (see talk by E. Lipka)✓ Developments and testing of new MC generators and techniques

CMS-PAS-SMP-15-004

Z invisible width

see talk by
A. theLanyovdetails
Highlights
fromCMS forExperiment20.08.2021

CMS-PAS-SMP-18-014

the first measurement of the Z invisible width
at a hadron collider and is the single most7
precise direct measurement in the world

Gauge Boson Differential x-sections
Measurements of different production processes continue and more and more differential ones
 differential cross sections of the transverse momentum pT, the angular variable φ*, and rapidity oflepton pairs - tests in (x,Q2) space
Z production

JHEP 12 (2019) 061; PAS-SMP-20-003

no significant
deviationfrom SMpredictions(NLO/NNLO)

W production

Highlights from the CMS Experiment20.08.2021

8NLO pQCD Strinjent Tests: V+jets, VV+jets
W + 2 jets

EPJ C 80 (2020) 43

ZZ + jets

Agrees with theleading orderstandard model
prediction!
Highlights from the CMS Experiment20.08.2021

PLB 789 (2019) 19-44

9EWK Self-Couplings: Multi-bosons
Gauge boson pair production (Wγ, Zγ, WW, WZ, ZZ) Triple gauge boson production (WWW, WWZ,
✓ aTGC testsWZZ, Wγγ, Zγγ)
✓ studies of VBF и VBS (Wγjj, Zγjj, WWjj, WZjj)
mechanisms in the context of the Higgs production andaQGC✓ high-order corrections, pQCD tests, New Physics✓ aQGC tests✓ high-order corrections, pQCD tests,
New Physics

PRL 125, 151802 (2020)
arXiv:2107.01137, sub. PRL

EPJC 81 (2021) 200

arXiv:2106.11082, sub. PRD

Z+2jets,  = 5.21  0.75 fb
arXiv:2105.12780, sub. JHEP

Significancehttp://cms-results.web.cern.ch/cms-results/public-results/publications/SMP/ATGC.html
Highlights from the CMS Experiment
http://cms-results.web.cern.ch/cms-results/public-results/publications/SMP/AQGC.html
20.08.2021✓combined - 5.7 (5.9) σ✓ WWW – 3.3 (3.1) σ✓ WWZ – 3.4 (4.1) σ 10

QCD: jet physics✓ tests of theory
Compared to Powheg + Pythia8, Herwig++− pQCD
Agreement with NLO is in general better than LO− non-perturbative regime✓ parton structure (PDF)✓ measurement of the the running coupling constant✓ etcs-quark PDF from W+c

EPJ C 79 (2019) 269

c- and b-quarks PDFs
from W+c/Z+c/Z+b

EPJC 78 (2018) 287
JHEP04(2021)
109Highlights
fromthe CMS Experiment20.08.2021

see talk by O. Kodolova for details

11Dijet Azimuthal Correlation (Njets > 2,3,4)
EPJ C 78 (2018) 566,
CMS-PAS-SMP-21-006

The leading order (LO) PYTHIA 8 dijet event generator exhibits small deviations from the measurements but
shows significant deviations at low-pT
The HERWIG++ event generator exhibits the largest deviations of any of the generators
The tree-level multijet event generator MADGRAPH in combination with PYTHIA 8 for showering, hadronization,and multiparton
interactions
provides a goodoverall
description of the measurements
Highlights fromthe CMS
20.08.2021
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Mass of “top”: Legacy of Run 1/2
see talk by H. Liao for details

precision~0.3%
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Running of the Top Quark Mass/Vtb
Beyond leading order in perturbation
Non-direct Vtb measurements
theory the strong coupling constant and ✓ from B-hadron and t-quark decays (CKM unitarity,the quark masses are subject togeneration number=3)
renormalization✓ |Vtb| > 0.78 (CDF), 0.99 >|Vtb| > 0.9 (D0)
PLB 803 (2020) 135263

Direct Vtb measurements from single t-quark production int-, Wt, s-каналах (σ ~ Vtb2)

Br (t → Wb) ≈ 1
fLV =1 (no NP terms)
The running of mt is found to be in agreementwith the RGE prediction within 1.1 σ
The no-running hypothesis is excluded atabove 95% confidence level
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Rare Decays: BS/B0 →μμ
In the SM:Br(BS → ): (3.570.30)10-9Br(B0 → ): (1.070.10)10-10
Measurements @ 13 TeV:Br(BS → ): (2.90.27)10-9
Br(B0 → ) < 3.610-10

JHEP 04 (2020) 188

B physics resultsfrom CMSPRL 111 (2013) 101804

LHCb : ( ~5%)No significant excess from SM predictions are observed! see talk by
A. Tulupov forhttps://cms-results.web.cern.ch/cms-results/publicother B physics
results/preliminary-results/BPH/index.html
Highlights from the CMS Experimentresults from CMS

20.08.2021

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Higgs Mass Measurementsfrom talk by G. Hamel de Monchenault (HEP2021)
Highlights from the CMS Experiment

see talk by G. Mitselmakher for details
20.08.2021

16Higgs Properties (selected)
Simplified Template
Cross Sections (SXTS)
H → γγ, ττ, ZZ*(→4l)
produced via gg,VBF, VH, and t(t)H

JHEP 07 (2021) 027

Contraints on ttH anomalous CP coupling,combining H → 4ℓ and H → γγ
CMS-HIG-19-009, sub. to PRD

SXTSH → γγCMS-PAS-HIG-19-010

The rate for Higgs bosons production inassociation with either one (tH) or two (ttH)
top quarks in multi-lepton channel

EPJC 81 (2021) 378ttH (H → 4ℓ) Candidate

SXTS H → ττHighlights from the CMS Experiment20.08.2021

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Evidence for H → μμFirst evidence of the coupling of the Higgs boson with fermions of the second generation
JHEP 01 (2021) 148

H → μμ candidate in gluon fusion channel, mH = 125.46 ± 1.13 GeV
targets
ggH, VBF , VH, ttH
best sensitivity
Drell-Yan backgroundconsiderably reduced
by VBF topology
requirement (twoforward jets)

Obs. (exp.)
significance is
3.0σ (2.5σ).

+0.15
𝜇 = 1.19+0.40−0.39 (𝑠𝑡𝑎𝑡)−0.14 (𝑠𝑦𝑠𝑡)

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Higgs Differential Cross Sections
Differential cross sections as a function of the transverse momentum and rapidity of the Higgs boson,
the number of associated jets, and the transverse momentum of the leading associatedjet are measured.
EPJC 81 (2021) 488

no significant
deviationfrom SMpredictions

JHEP 03 (2021) 003
PLB 792 (2019) 369

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Search for pair-production of Higgs

from talk by K. Mazumdar (QCD 2021)
Highlights from the CMS Experiment20.08.2021

20Searches for Extra Higgs/Exotic Higgs Decays
X→ aa → 4b

CMS-PAS-B2G-20-003

H → Invisible
A broad program in BSM Higgs
searches:additional Higgses,
invisible decays, lepton-flavourviolating decay and 2HDM+scalarmodels with h→aa, Charged
Higgses,… EPJ C 81 (2021) 13Single and double charged
Higgs boson

arxiv:2104.04762

The analysis is restricted to themass ranges ma from 25 to 100
GeV and mX from 1 to 3 TeV.
see review talk by G. KoleHighlights from the CMS Experiment

No significant excess beyond
Observed upper limit from Z (ℓℓ) standard model predictions isH, H→invisible: BR(H→invisible) found. Charged Higgs boson< 29% @95% CL
mass explored: 200 – 3000 GeV
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Higgs decays and long-lived particles
Search for Long-Lived Particles produced in pairs✓ with a mean decay length between 0.1 and100 mm (i.e. within the beam pipe)✓ each decaying into two or more quarks

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Searches for Heavy Resonances
New Physics (Z/ZKK/GKK) contributions to SM processes
Dileptons, full RUN2 data

JHEP 07 (2021) 208
W, full RUN2 data

arXiv:2106.10509,
sub. PLB

RS1 graviton

Lepton flavor universality

Z’ bosonsee review talk by A. Kaur for details
Highlights from the CMS Experiment20.08.2021

benchmark heavy scalar (vector) triplet bosons
with masses between 0.75 (1.15) and 1.40 (1.36)
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TeV are excluded at 95% CL

Example of Dark Matter Searches
Effective approaches to DM

SMDM✓ Simplified DM model (SMDM) with jne DM spin ½particle χ, one mediator✓ Flavour-violating vector mediator, color charged scalar
mediator✓ Extend higgs sector (higgs portal) and/or gauge sector(2HDM+a/S/Z’)✓ Double portals (scalar and vector mediators)✓ etc

2HDM+Z’mMed-mDM plane for di-jet and di-lepton searches(SMDM)

2HDM+asee review talk of M. Savina

Exclusion limits for the pseudo-scalar model as a functionof Mmed for different MET based DM searches from CMS

j/V(qq), Z(ll), t/tt + DM(MET)

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Summary of Exotica Searches
https://twiki.cern.ch/twiki/bin/view/CMSPublic/SummaryPlotsEXO13TeV

see review talk by A. KaurCI

Dark Matter

RPV SUSY

Extra Dimensions
Excited Fermions
Heavy Fermions
Leptoquarks

Heavy GaugeBosonsПоиск новойфизики
экспериментеCMS на LHC
Highlights
fromвtheCMS Experiment20.08.2021 1 TeV

10 TeV

30 TeV25

Example of Supersymmetry Searches

from talk by G. Hamel de Monchenault (HEP2021)

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Summary
Despite the pandemic, the CMS Physics Analysis, LS2 and Phase 2 Upgrade activities areprogressing well✓ Many new analyses made public for Summer Conferences,
http://cms-results.web.cern.ch/cms-results/public-results/preliminaryresults/CMS/index.html✓ Physics Briefings at: https://cms.cern/tags/physics-briefing✓ Run 3 preparation ongoing−−−

LS2 work mostly complete
Detector almost ready to be closed to cool down and commission the magnet by October
Currently taking cosmic data for alignment
CRUZET Cosmic RUn at ZEro Tesla
Phase-II Upgradesfor detector alignment✓ Excellent progress in all projects
July/August 2021
✓ All Technical Design Reports prepared✓ More physics projections for HL-LHC starting to appear

we are looking forward toHighlights from the CMS Experiment20.08.2021

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