Download Transparancies for Fundamental Forces and Particles

Particle Physics
Part 1
•Review: Fundamental forces and particles
•Feynman diagrams
•Experimental QCD
•Accelerators and Detectors
•Electroweak Theory
Part 2
•Experimental Electroweak
•Higgs searches
•Top Quark
•Heavy Flavour physics
•Neutrinos
•Beyond the Standard Model
http://ppewww.ph.gla.ac.uk/~parkes/teaching/PP/PP.html
Chris Parkes & Rick StDenis
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Revision of
Fundamental Particles & Forces
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Standard Model Fermions & Bosons
Standard Model Structure
Common Mesons & Baryons
Natural units
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Particle Physics
Aim: Understand the fundamental
particles and forces of nature.
Tools: Particle colliders operating at the
highest energies achievable.
It involves the biggest, most complicated experiments in the history
of science, with the fastest computers, the coldest temperatures and
the strongest magnets on Earth.
Particle physics re-creates the universe just after the Big Bang and
hopes to answer the questions that humans have been asking for
eternity; “Where do we come from?” “What are we made of?”
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Some alternative reasons to study
1. I want a nobel prize!
this course!
2004 – QCD
1999 – QFT
1992 -- particle detectors
1988 -- muon neutrino
2002 – neutrinos
1995 -- tau / neutrino
1990 -- Deep Inelastic Scattering
1984 -- W&Z bosons
2. I want to understand why 5000 physicist worldwide are currently building the
world’s largest machine!
LHC @ CERN
2 PhD places in Glasgow for Oct. 2008
•27 km long tunnel,100m underground
•French/Swiss Border near Geneva
•2007 onwards Large Hadron Collider (LHC),
14 TeV proton collider
•Origin of mass (Higgs Boson)
•New Physics (e.g. Supersymmetry)
•Matter anti-matter asymmetry in Universe
(CP Violation)
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Standard Model – Particle Physics
• Summarises the current knowledge
• Quantum theory that includes :
– unified theory of weak and electromagnetic
(QED) interactions (ElectroWeak)
– Strong Interactions (Quantum
chromodynamics – QCD)
– Does not include gravity
– Includes one boson – the Higgs – which
has not yet been discovered….
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+ Higgs boson, spin 0, electric charge 0, mass unknown yet…..
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Strength – see section on running coupling constants later
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Composite particles
Or where the quarks hide….
•Mesons are quark anti-quark system
Integer spin particles
About 140 types are known
•Baryons are three quark / three anti-quark systems
About 120 types are known
Details of all known at http://pdg.lbl.gov/
Some common ones on the next pages
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Light Flavour Mesons
Particle
Symbol
Antiparticle
π-
Makeup
Rest mass
MeV/c2
Lifetime
(s)
Decay Modes
139.6
2.60
x10-8
μ+νμ
135.0
0.83
x10-16
2γ
1.24
x10-8
μ+νμ, π+π0
0.89
x10-10
5.2
x10-8
π+π-,2π0
0.4
x10-23
20
x10-23
π+π-
Pion
π+
Pion
π0
Self
Kaon
K+
K-
us
493.7
Kaon
K0s
K0s
su
497.7
Kaon
K0L
K0L
su
497.7
Rho
ρ0
Self
uu, dd
770
Phi
φ
Self
ss
1020
ud
π+e-νe
K+K-10
,K0K0
Particle
Symbol
Antiparticle
Makeup
Rest mass
Lifetime
MeV/c2
D
D+
D-
cd
1869.4
D
D0
D0
cu
1864.6
D
D+s
D-s
cs
1969
Self
cc
3096.9
J/Psi
J/ψ
B
B-
B+
bu
5279
B
B0
B0
db
5279
Bs
Bs
0
sb
5370
bb
9460.4
Upsilon
0
ϒ
Bs
Self
10.6
x10-13
4.2
x10-13
4.7
x10-13
0.8
x10-20
1.5
x10-12
1.5
x10-12
...
1.3
x10-20
Decay Modes
K + _, e + _
[K,μ,e] + _
K+_
e+e-, μ+μ-...
D0 + _
D0 + _
D-s + _
e+e-, 11μ+μ-..
Baryons -1
Symbol
Makeup
Rest mass
MeV/c2
Spin
Proton
p
Neutron
n
uud
ddu
938.3
939.6
1/2
1/2
Lambda
Λ0
uds
1115.6
1/2
Sigma
Σ+
uus
1189.4
1/2
Sigma
Σ0
uds
1192.5
1/2
Sigma
Σ-
dds
1197.3
1/2
Delta
Δ++
uuu
1232
3/2
Delta
Δ+
uud
1232
3/2
Particle
Lifetime
(seconds)
Stable
920
2.6
x10-10
0.8
x10-10
6x10-20
1.5
x10-10
0.6
x10-23
0.6
x10-23
Decay Modes
...
pe-νe
pπ-, nπ0
pπ0, nπ+
Λ0γ
nπpπ+
120
pπ
Baryons -2
Particle
Symbol
Makeup
Rest mass
MeV/c2
Spin
Delta
Δ0
udd
1232
3/2
Delta
Δ-
ddd
1232
3/2
Xi
Cascade
Ξ0
uss
1315
1/2
Xi
Cascade
Ξ-
dss
1321
1/2
Omega
Ω-
sss
1672
3/2
Lambda
Λ +c
udc
2281
1/2
Lifetime
(seconds)
0.6
x10-23
0.6
x10-23
2.9
x10-10
1.64
x10-10
0.82
x10-10
2x10-13
Decay Modes
nπ0
nπΛ0π0
Λ0πΞ0π-, Λ0K...
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Natural Units, =c=1
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Energy GeV
Momentum GeV/c (abbreviated to GeV)
Mass GeV/c2
Length (GeV/c)-1
c=0.197GeVfm=1 [1fm=1E-15m]
– Natural unit of length 1GeV-1=0.197fm
Time (GeV/ )-1 =6.6E-25GeVs
– Natural unit of time 1GeV-1=6.6E-25s
Cross-section (GeV/c)-2
1barn=10-28m2
– Natural unit of xsec =1GeV-2=0.389mb
Charge - ‘Heavyside-Lorenz units’ ε0=1
Use dimensionless ‘fine structure constant’
e2
e2
1
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40c 4 137
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