Download presentation
Presentation is loading. Please wait.
Published byRoderick Rice Modified over 9 years ago
1
Introduction of Nuclear Physics
2
How can we probe the structure in the smaller scale? Discovery of nuclear structure Development of nuclear physics –Nuclear structure –Exotic nuclei –Heavy ion collisions –Relativistic heavy ion collisions –Virtual photon from deep inelastic scattering with electron beam –Laser-electron photon, Bremsstrulumg photon –Laser Nuclear Physics
4
1897 – ELECTRON discoveryJ.J. Thomson 1909 – PROTONdiscovery E. Rutherford 1932 – NEUTRONdiscoveryJ. Chadwick 1935 – EXCHANGEtheoryYukawa 1948 – QEDtheoryFeynman,… 1961 - W & ZtheoryGlashow 1964 – QUARKtheoryGell-Man, Zweig 1964 – HIGGStheoryHiggs, Englert,… 1967 – ELECTROWEAK theoryWeinberg, Salam,… 100 Years of Particle Physics
5
1971 – NON-ABELIANt’Hooft, GAUGEtheoryVeltman 1972 – QCDtheoryGell-Man, Frizsch 1973 – ASYMPTOTICGross, FREEDOMtheoryWilzcek, Politzer 100 Years of Particle Physics
6
1974 – CHARMdiscoveryTing, Richter 1977 – BOTTOMdiscoveryLederman JADE 1979 – GLUONdiscoveryTASSO, JADE, MARK-J, PLUTO 1983 – W & ZdiscoveryRubbia/UA1 UA2 DØ 1995 – TOPdiscovery DØ & CDF 100 Years of Particle Physics
7
Geiger-Marsden experiment The Geiger-Marsden experiment (also called the Gold foil experiment or the Rutherford experiment) was an experiment done by Hans Geiger and Ernest Marsden in 1909, under the direction of Ernest Rutherford at the Physical Laboratories of the University of Manchester which led to the downfall of the plum pudding model of the atom. They measured the deflection of alpha particles (helium ions with a positive charge) directed normally onto a sheet of very thin gold foil. Under the prevailing plum pudding model, the alpha particles should all have been deflected by, at most, a few degrees. However they observed that a very small percentage of particles were deflected through angles much larger than 90 degrees; some were even scattered back toward the source. From this observation Rutherford concluded that the atom contained a very physically-small (as compared with the size of the atom) positive charge, which could repel the alpha particles if they came close enough, subsequently developed into the Bohr model.
8
Low-Energy electron scattering from Carbon
9
High-Energy electron scattering from Carbon
10
Parton Structure of Proton - Quark
12
Elementary Particles discovered: 1898 1964 1953 Donald Glaser invented the bubble chamber. The Brookhaven Cosmotron, a 1.3 GeV accelerator, started operation.
13
Back to Year 1964 A hundred or so types of particles were identified: –Baryons (fermion): n, p, , , , …. –Mesons (boson) : , , ….. quarksMurray Gell-Mann (Mendeleev of elementary particle physics) proposed “ the eightfold way ” to put these particles in order, suggesting more elementary constituents: quarks. –Three types of quarks, u, d and s. –Baryons composed of 3 quarks. –Mesons composed of 2 quarks: a quark and an antiquark.
14
Baryon Octet (s=1/2)
15
Meson Octet (s=0)
16
Baryon Decuplet (s=3/2) (1232) (1384) (1533) (1672)
18
Deep Inelastic Scattering with Electrons beam
20
A November revolution: the birth of a new particle J/ BNL: p+A e+e- X SLAC: e+e- X
22
http://ed.fnal.gov/projects/exhibits/s earching/exhibit_home2.html
25
Upsilon
27
Three-jet Events: Proof of “radiated” Gluon
28
1995 European Physical Society High-Energy and Particle Physics Prize
29
Observation of “Neutral Currents” in 1973
30
Discovery of W and Z in 1983 http://cern-discoveries.web.cern.ch/CERN-Discoveries/Courier/HeavyLight/Heavylight.html http://cern-discoveries.web.cern.ch/CERN-Discoveries/Courier/HeavyLight/Heavylight.html On 25 January 1983, CERN called a press conference to announce the discovery of the W particles.
32
W and Z Production Isolated, high p T leptons Missing transverse momentum in W's Z events provide excellent control sample Typically small hadronic (jet) activity Number of candidates in ~200pb -1 : ~64000 W e ~51000 W ~2900 Z ee ~4900 Z
33
W Mass Measurement W mass information contained in location of transverse Jacobian edge Insensitive to p T (W) to first order. Reconstruction of p T sensitive to hadronic response and multiple interactions Provides cross-check of production model. Needs theoretical model of p T (W) Provides cross-check of hadronic modelling
34
Detector Calibration: Lepton Energy Scale Energy scale measurements drive the W mass measurement Calibrate lepton track momentum with mass measurements of J/ and decays to Calibrate calorimeter energy using track momentum of e from W decays Crosscheck with Z mass measurement, then add Z's as a calibration point Z Z ee
35
Signature of Top Quark Production
37
e+e- X around Z bosons : Proof of “three-generation” of neutrios
40
A hadron event - a neutrino interacting with a nucleon and emerging as a neutrino : first observation of "neutral currents" in the Gargamelle heavy liquid bubble chamber.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.