240 likes | 259 Views
Hunting for the Higgs at LHC. Konstantin Goulianos RU HOL FORUM October 6, 2011. The key to mass?. u. d. u. M g, g = 0 M W, Z ~100 m p M top ~M gold. About the Higgs. The Standard Model (SM) (Glashow, Salam and Weinberg – 1979 Nobel prize). Symmetry: SU3XSU2XU1. WS. SM.
E N D
Hunting for the Higgs at LHC Konstantin Goulianos RU HOL FORUM October 6, 2011 The key to mass?
u d u Mg, g = 0 MW, Z~100 mp Mtop~Mgold About the Higgs The Standard Model (SM) (Glashow, Salam and Weinberg – 1979 Nobel prize) Symmetry: SU3XSU2XU1 WS SM H Mw and MZ In the SM all particles have zero mass The Higgs field is needed to renormalize the theory “generates” mass – but not its own mass
Higgs mechanism solves mass hierarchy problem • Higgs:renormalizes the theory (removes infinities) • one neutral Higgs boson • “generates” the quark masses by coupling to quarks ~ mass.
Mg, g = 0 MW, Z~100 mp Mtop~Mgold The SM & RU predict charm in 1979 – Glashaw, Iliopoulos (RU) , Miani Fermilab 1995 CERN 1970s Evidence for quarks BNL 1962 (my PhD thesis at Columbia) BNL 1981 nmp nmp evidence for Z Z discovered at CERN in 1983 H What are we doing now in the search for the Higgs?
Rutherford Experiment Source a-particles Large angle scattering atoms have nuclei Particle accelerators 1910 Fermilab Tevatron 1985 LHC 2010 4 mile (6.4 km) tunnel 2 TeV 27 km tunnel 7 TeV CDF D0
The Larhe Hadron Collider CERN CMS LHCb ALICE ATLAS ATLAS Large Hadron Collider 27 km circumference Lake Geneva 6 T. Virdee, ICHEP08
Collisions at LHC search down to 1 part in 1013
m m e e Higgs searches at CMS - I Hgg Ht+t- Hbb (displaced vertex) HW+W- HZ0Z0 (Z0e+e- /m+m-) let let HZZ leplon leplon
Super-symmetry (SUSY) • The SM is not stable at high energies because of loop corrections • SUSY renormalizes the SM by introducing opposite sign contributions • The lightest SUSY particle (LSP) escapes detection candidate for dark matter …but what about dark energy???
POMERON H p+pp'+H+p' dipole beam dipole p’ H beam p’ roman pots roman pots Phys. Rev. D 77, 052004 Exclusive Higgs Production
Higgs discovery limits Tevatron range With 5fb-1 & combination of CMS+ATLAS data the SM Higgs exclusion reach is in the range140<MH<600GeV The non-discovery of the SM Higgs will be an even bigger discovery!
HOL talk in 2004 The Lab Anwar Luc Stefano Michele Mary Koji Christina Andrea Ken (student) 2011 Sarah Robert Jim http://physics.rockefeller.edu/ Vadim and Joe (machine shop)
Neutrino mass hierarchy problem Accelerator and CR experiments M212 ~ 7.9x10-5 eV2. From cosmology: CMB and large scale structure experiments Σ =0.03<m1+m2+m3.<0.05eV
Threading the MiniPlug fibers About 1500 wavelength shifting fibers of 1 mm dia. are ‘strung’ through holes drilled in 36x¼” lead plates sandwiched between reflective Al sheets and guided into bunches to be viewed individually by multi-channel photomultipliers.
Incident hadrons acquire color and break apart POMERON CONFINEMENT p-p Interactions Non-diffractive: Color-exchange Diffractive: Colorless exchange with vacuum quantum numbers rapidity gap Incident hadrons retain their quantum numbers remaining colorless pseudo- DECONFINEMENT Goal: understand the QCD nature of the diffractive exchange
Non-diffractive interactions Diffractive interactions Rapidity gaps are formed by multiplicity fluctuations: Rapidity gaps at t=0 grow with Dy: 2e: negative particle density! P(Dy) is exponentially suppressed Gravitational repulsion? Dark Energy http://physics.rockefeller.edu/dino/myhtml/talks/goulianos_konstantin_eds09_discussion.pdf http://physics.rockefeller.edu/dino/myhtml/conference.html