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Higgs and Dark Matter. Yeong Gyun Kim (GNUE). The World’s largest accelerator. Over 3000 scientists from 38 countries are taking part in ATLAS alone. A 16 page paper of CMS. More than 10 pages for author list . Integrated luminosity 2010-2012. Fundamental Questions.
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Higgs and Dark Matter YeongGyun Kim (GNUE)
Over 3000 scientists from 38 countries are taking part in ATLAS alone
A 16 page paper of CMS More than 10 pages for author list
Integrated luminosity 2010-2012 Moriond QCD 2013
Fundamental Questions • What are the most basic building blocks of the universe? • How do they interact with each other?
원자 가설 (atomic hypothesis) 모든 물질은 원자로 이루어져 있으며, 이들은 영원히 운동을 계속하는 작은입자이다. John Dalton 1766-1844 원자론은 존 돌턴에 의해 부활되었다. 그는 모든 물질이원자로 구성되어있다는 가정하에 화학반응을 성공적으로 설명하였다.
Richard Phillips Feynman (1918–1988) 다음 세대에 물려줄 과학적 지식을단 한 문장으로 요약해야 한다면, 그것은 ‘원자가설’일 것이다.
The Nobel prize in 1906 The Nobel prize in 1908 음극선 실험을 통한 전자의 발견 (1897) J.J. Thomson 금박실험을 통한 원자핵 발견 (1911) 양성자 발견 (1919) E. Rutherford
The Nobel prize in 1935 “for the discovery of the neutron” 중성자 발견 (1932) J. Chadwick 원자핵은 양성자와 중성자로 이루어져 있다 그 후, ‘양성자와 중성자는쿼크로 이루어져 있다’는 것이 밝혀진다 양성자 중성자
The Nobel prize in 1990 Friedman Kendall Taylor SLAC 연구소의 물리학자들이양성자 내부에 있는 쿼크에대한 최초의 증거를 발견했다(1968)
원자핵 붕괴과정에서 생성되는 전자의 에너지가 연속적인 분포를 갖는 것이 관측됨
N. Bohr 에너지, 운동량이 보존되지 않는가? W. Pauli 새로운 가벼운 중성입자가 필요한가 ? (1930)
The Nobel prize in 1995 “for the detection of the neutrino” 중성미자(neutrino)의 발견 (Cowan and Reines, 1956) (observation of inverse beta decay) Fred Reines
Standard Model Particles & Higgs boson
God(damn) Particle • In the Standard Model, particle interactions are dictated by a local gauge symmetry SU(3)c x SU(2)L x U(1)Y. • Electroweak gauge symmetry is broken spontaneously by the vacuum value of a scalar (Higgs) field, giving masses to weak gauge bosons and matter particles. • This implies the existence of a new scalar particle (Higgs particle, aka God particle).
Higgs at the LHC • The most important SM Higgs boson production processes at the LHC
The SM Higgs branching ratio For mH = 125 GeV, BR(h bb) ~ 58 % BR(h WW*) ~ 21.6 % BR(h ZZ*) ~ 2.7 %BR(h ττ) ~ 6.4 % BR(h γγ) ~ 0.22 % BR(h gg) ~ 8.5 %
Search Channels for Higgs Leptons/Photons essential for any search For All production mode For WH/ZH production
Global Fit to Higgs data Best fit converged towardsthe SM; in particular datanow disfavor the solution with c < 0 which appearedin previous fits and gave anenhanced h γγGiardinoet al. arXiv:1303.3570
Invisible Higgs Decays A universal reduction of the rates in all decaychannel Severely constrained by Global fits Giardinoet al. arXiv:1303.3570
An image of the cluster Abell 2218 (taken with the Hubble space telescope)
Cosmic Microwave Background Anisotropies WMAP satellite
Dark Matter Halo Dark Matter in a galaxy surrounds the visible matter in a halo.It might be detected through various ways.
Direct Detection • Dark Matter particles in the halo might be detected by its elastic scattering with terrestrial nuclear target.
Indirect Detection • Neutrino Telescopes (e.gIceCube) High Energy Neutrinos from DM annihilation at the core of SUN can be detected, via ν μ conversion
Indirect Detection • Search for DM annihilation into gamma rays, antiparticles (antiproton, positron)
Positron Excess • Pulsars remain the best explanation of PAMELA/Fermi excess • Dark Matter Explanations are tough • Large rates into e+e- • Low rates into antiprotons • But, viable scenarios exist
A Gamma-ray Line • Positrons are too messy • The observation of gamma-ray line in the cosmic-ray fluxes would be a smoking-gun signature for dark matter annihilation in the universe • Weniger found such gamma-ray signatures in the data of Fermi-LAT
DM production at Colliders Large Missing Energy (+ jets, leptons etc)