Measurement of Higgs bosons decaying to Tau lepton

Measurement of Higgs bosons decaying to Tau lepton pairs and Constraints on Anomalous HVV couplings. Sam Higginbotham

The Higgs Boson and Taus • Use taus to investigate properties of the Higgs: • Good Branching Fractions • Excellent online selection • Higgs couples to mass. Tau is the most massive lepton Sam H. , USLUA Meeting • Tau Decays hadronically (τh ) and leptonically • Hadron Plus Strips to identify π’s in τh decays 2/28/2021 • Tau Identification: 2

Signals and Final States VBF • Production Mechanisms: gg. H • Final States Sam H. , USLUA Meeting 2/28/2021 • Vector Boson Fusion (VBF) • Gluon Fusion (gg. H) • Challenges: • Jets faking taus • Leptons faking taus 3

Event Categorization and Fit Model • 3 Event Categorizations: • Shown below is the 0 -jet category for each channel Categorization τ hτ h µτh eτh 0 - Jet eµ Sam H. , USLUA Meeting • 0 -jet category is used to constrain backgrounds, VBF and Boosted for signal extraction 2/28/2021 • For a final fit, most categories and channel use a 2 D fit in the limits to extract significance for the mass of the ττ system • 0 -jet criteria: no jet > 30 Ge. V, |η| < 4. 7, and loose particle flow I. D. eµ and τhτh don’t resonate sharply around Z … for τhτh 1 D is used for high pt threshold 0 jet has better separation in visible mass 4

QCD Sig OS Loose Same Sign SS Tight SS Loose τh: 1, 2 Isolated τh: 1 anti-Iso τh: 2 anti-Iso 2/28/2021 • Opposite Sign Sam H. , USLUA Meeting Background Methods 5

IV IV III II II I I Sam H. , USLUA Meeting 2/28/2021 • 2 D categories are split and unrolled, VBF category in the μτh channel shown • The Z and Higgs are well separated with the Z at 90 Ge. V and Higgs at 125 Ge. V 6

2/28/2021 IV IV IV III II II I I Sam H. , USLUA Meeting • 2 D categories are split and unrolled, I II III shown below • The Z and Higgs are well separated in with the Z at 90 Ge. V and Higgs at 125 Ge. V 7

2/28/2021 IV IV IV III II II I I Sam H. , USLUA Meeting • 2 D categories are split and unrolled, I II III shown below • The Z and Higgs are well separated in with the Z at 90 Ge. V and Higgs at 125 Ge. V 8

• The S/(S+B) weighted distribution is shown on the right • p-value scan shows 5σ sensitivity Sam H. , USLUA Meeting 2/28/2021 Performance of 2 D Fit 9

• The S/(S+B) weighted distribution is shown on the right • p-value scan shows 5σ sensitivity Sam H. , USLUA Meeting 2/28/2021 Performance of 2 D Fit 10

• Matrix Element Likelihood Analysis (MELA) can be used to constrain couplings in HVV processes such as Higgs coupling to ZZ, WW, Zγ, γγ, and gg : *HIG-17 -011 • Build discriminant with MELA to make an optimal observable Sam H. , USLUA Meeting 2/28/2021 Using MELA in • For the future, use discriminant in conjunction with Machine Learning for 2 D or 3 D fit! 11

Sam H. , USLUA Meeting 2/28/2021 • We may use Machine Learning and MELA in the final 2 D or 3 D fit. F. P. R Future Studies Work in Progress 1 -T. P. R Work in Progress • R. O. C. Curve with BDTs trained in VBF category • Msv shown after preliminary BDT cut in Boosted Category 12

Sam H. , USLUA Meeting • CMS Detector Public Page: Link • HIG-17 -011 Observation of the SM scalar boson decaying to a pair of tau leptons with the CMS experiment at the LHC, CMS PAS HIG-16 -043 Link • Constraints on anomalous Higgs boson couplings using production and decay information in the four-lepton final state, HIG-17 -011 Link • Constraints on anomalous HVV couplings in production of Higgs bosons decaying to tau lepton pairs, CMS CADI HIG-17034 2/28/2021 References 13

Sam H. , USLUA Meeting Thank you 14 2/28/2021

Sam H. , USLUA Meeting 2/28/2021 Backup 15

Full Event Categorization and Fit Model • 3 Event Categorizations: 0 jet has better separation in visible mass. Low DY lepton faking tau in 3 prong DM. Categorization ττ µτ eτ 0 - Jet Boosted VBF The signal/backgroun d of the Higgs increase as a function of Higgs. Pt. eµ Sam H. , USLUA Meeting 98% gg. H signal, eµ and ττ don’t resonate sharply around Z … for ττ 1 D is used for high pt threshold 2/28/2021 • For a final fit most categories and channel use a 2 D fit in the limits to extract significance for the mass of the ττ system The signal/background of the Higgs increase as a function of di-jet invariant mass 16