di-higgs signatures from r-parity violation for neutrino mass · 2016-08-30 jeonju di-higgs from...
Post on 05-Oct-2020
2 Views
Preview:
TRANSCRIPT
Di-Higgs signature from R-parity violation for
neutrino mass
Eung Jin Chun
1st IBS-Honam Focus Program, Jeonju, 29-31 Aug. 2016
in collaboration with Sanjoy Biswas and Pankaj Sharma, 1604.02821
Motivation
• Supersymmetry – still a promising framework for naturalness
• R-parity violation – abandons LSP dark matter candidate but explains neutrino masses and mixing
• Higgsino LSP scenario – minimizing the fine-tuning in EWSB
• Higgsino decays thu RpV mainly to 𝜈ℎ: 𝑝𝑝 → ෩𝐻 ෩𝐻 → ℎℎ +𝑀𝐸𝑇
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 2
Di-Higgs at the LHC
• Measurement of the Higgs self-coupling (needs 100 TeV machine).
• Search for Xhh.
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 3
2014-019: ATLAS 𝑏𝑏𝛾𝛾 study
Bilinear RpV & Neutrino Masses
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 4
• Bilinear RpV terms:
• Neutrino-neutralino mixing mass:
Bilinear RpV & Neutrino Masses
• Neutrino mass matrix from seesaw by neutralino
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 5
∝ 𝐷𝑒𝑡(𝑀𝑁)
• Neutrino oscillation data determine
Mixing induced by BRpV
• 𝜈 − 𝜒0 mixing:
• 𝑙 − 𝜒− & 𝑙𝑐 − 𝜒+ mixing:
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 6
RpV vertices for 𝜒 → 𝑙𝑊, 𝜈𝑍, 𝜈ℎ
• 𝜒 − 𝑙 −𝑊:
• 𝜒 − 𝜈 − 𝑍:
• 𝜒 − 𝜈 − ℎ:
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 7
Branching ratio of the 𝜈ℎ channel
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 8
Higgsino pair production & di-Higgs channels at LHC14
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 9
Signaling the 𝛾𝛾𝑏𝑏 +𝑀𝐸𝑇 channel
• Basic cuts:
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 10
𝑝𝑇𝛾> 10 𝐺𝑒𝑉 & 𝜂𝛾 < 2.5
pTb > 20 GeV & 𝜂𝑏 < 2.5
Δ𝑅 𝑗𝑗,𝑗𝑏,𝑏𝑏,𝛾𝑗,𝛾𝑏,𝛾𝛾 > 0.4
Photon cut: 𝑝𝑇(𝛾1,𝛾2) > 30,20 𝐺𝑒𝑉
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 11
Invariant mass cut: 𝑀𝛾𝛾 −𝑀ℎ < 2.5𝐺𝑒𝑉, 𝑀𝑏𝑏 −𝑀ℎ < 15𝐺𝑒𝑉
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 12
MET cut:𝑀𝐸𝑇 > 100𝐺𝑒𝑉
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 13
Separation cut:Δ𝑅𝑏𝑏,𝛾𝛾 < 2.0
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 14
Cut flow on the backgrounds
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 15
Basic Photon pT Invariant mass MET Δ𝑅
Cut flow on the signals
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 16
Basic Photon pT Invariant mass MET Δ𝑅
Signal significances
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 17
Conclusion
• Di-Higgs search is the next step to probe the EWSB sector.
• Light Higgsino is preferred for naturalness and hard to probe at LHC.
• Higgsino LSP in RpV SUSY opens a large parameter scape to produce di-Higgs with missing energy.
• Promising is the 𝑏𝑏𝛾𝛾 +𝑀𝐸𝑇 channel: small BR but much less background.
• Missing energy is a clean discriminant and allows us to probe the Higgsino mass up to ~600 GeV at HL-LHC with 3/ab.
2016-08-30 Jeonju Di-Higgs from RpV EJChun@KIAS 18
top related