t h e c o l o r f u l s e e s a w
DESCRIPTION
T h e C o l o r f u l S e e s a w. 12 – April- 2011 The Role of Heavy Fermions in Fundamental Physics. Sogee Spinner University of Wisconsin-Madison. JHEP 1101 (2011) 046: P. Fileviez Perez, T. Han, SS, M. Trenkel. Phys.Rev . D80 (2009) 053006 : P. Fileviez Perez, M. Wise. - PowerPoint PPT PresentationTRANSCRIPT
THE COLORFUL SEESAW
Sogee SpinnerUniversity of Wisconsin-Madison
12 – April- 2011
The Role of Heavy Fermionsin Fundamental Physics
JHEP 1101 (2011) 046: P. Fileviez Perez, T. Han, SS, M. TrenkelPhys.Rev. D80 (2009) 053006 : P. Fileviez Perez, M. Wise
2
QUEST FOR BSM
BSM
3
BSM IS ALREADY HERE: Neutrino Masses:
Can be Dirac or Majorana:
Majorana: new heavy particles:
Very exciting for LHC if MX ~ TeV
4
OUTLINENeutrino Mass Models
The Colorful Seesaw Fields
The Colorful Seesaw at the LHC
Conclusion
5
OUTLINENeutrino Mass Models
The Colorful Seesaw Fields
The Colorful Seesaw at the LHC
Conclusion
6
MAJORANA SCHEMES Generically: violates lepton number:
Possible same-sign dilepton signals
Type II: Scalar Produced via vector bosons Exciting signals from pair produced
Konetschny & Kummer; Cheng & Li; Lazarides et al.; Schechter & Valle; Mohapatra & Senjanovic
Fileviez Perez, Han, Huang, Li & Wang; Chun et al.; Garayoa & Schwetz; Akeroyd et al.; Huitu et al.
Type III: Fermion Fermionic also through Drell-Yan
Foot Lew, He & Joshi
Franceschini et al; Arhrib, Bajc, Ghosh, Han, Huang,Puljak & Senjanovic; Li & He, Aguila & Aguilar-Saavedra
Type I: Fermion Hard to produce without new interactions
Minkowski; Yanagida; Gell-Mann et al.; Glashow; Mohapatra & Senjanovic
Keung & Senjanovic; Han & Zhang; Aguila & Aguilar-Saavedra; Atre et al.; Kersten & Smirnov; Fileviez Perez et al.
7
Fileviez Perez, Wise ‘09
RADIATIVE SEESAW Zee Model: Scalar and
, LNV not clear
One type of scalar and one type of fermion :
Zee ‘80
8
CHOOSE COLORLESS FIELDS
Type I Seesaw
Fractionally charged
Fractionally charged
Type III Seesaw
9
COLORFUL FIELDS
Type I Seesaw
New
Fractionally charged
Fractionally charged
Type III SeesawNew
10
THE COLORFUL SEESAW
One massless neutrino Allows normal hierarchy (NH):
And inverted hierarchy (IH):
11
THE COLORFUL SEESAW
Neutrino Masses:
Loop Function
Compare to TeV type I seesaw:
12
LEPTON NUMBER VIOLATION Lepton number violation (LNV)
requires Lepton flavor violation (LFV) requires
(Liao & Liu ‘10; Fileviez Perez, SS, Trenkel ‘11) Order 1 Yν
Scanned over neutrino parameters.
13
OUTLINENeutrino Mass Models
The Colorful Seesaw Fields
The Colorful Seesaw at the LHC
Conclusion
14
SCALAR COLOR OCTET So called Manohar-Wise (‘06)
Higgs doublet color adjoint Couples to quarks just like Higgs
Therefore satisfies minimal flavor violation Ansatz (MFV)
Transforms as Higgs under flavor
Pheno has been studied Gresham & Wise; Fileviez Perez, Gavin, McElmurry &Petriell0; Gerbush et al.;
15
SCALAR COLOR OCTET Physical states:
Mass split by Higgs interactions: electroweak Mild coupling to down gives
fields fairly degenerate Decays:
For larger splitting, heavier S decay to W and lighter S, e.g.:
16
FERMIONIC OCTET Quantum numbers of gluino (same production) Decays governed by Yukawa coupling to Leptons
Use Casas-Ibarra (‘01) to relate :
is a complex matrix with
Assumed real, in normal hierarchy:
17
FERMIONIC OCTET DECAYS For
Various decay lengths:Could also be R-hadron.
Or three-body decays
Decay length: scan over and mixings.
18
DECAYS WITH TRI-BIMAXIMAL MIXINGS
No Phases NH: or channels always larger than
NH: and coincide
19
GENERAL MIXING
Scanned over mixing angles and phases Not as predictive
NH: and channel still larger then
20
OUTLINENeutrino Mass Models
The Colorful Seesaw Fields
The Colorful Seesaw at the LHC
Conclusion
21
PRODUCTION: SIMILAR TO GLUINO
22 Still before MET cuts
SIGNALS LNV: same-sign dileptons
Final states of interests:
Leading background: One pair of like-sign tops decay semi-
leptonically
23
NUMBER OF EVENTS FOR 10 fb-1:
Scanned over neutrino parameter Signal > background even before cuts, up to For 14 TeV, up to Large particle multiplicity makes reconstruction
challenging, but large number of events can make up for it
24
CONCLUSION Neutrino masses might lead to exciting LHC signals
Same-sign dileptons (LNV) with electroweak cross section
Colorful Seesaw also has same-sign dileptonsbut strong cross sections. One-loop seesaw mechanism Scalar color octet, isospin doublet S Fermionic color octet
More signal events than background up to With luck, might also discriminate: NH, IH