Fundamental Couplings

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Fundamental Couplings
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Feynman Diagrams
G1.116 x 10-5 GeV-2 MW80.4 GeV MZ91.2 GeV
W
Z
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Simplest Case nm e-?m- ne
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Grunge
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Finally the cross section
Flux factor
e- spin average
Isotropic
Total s
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Experimental Apparatus
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CHARM II at CERN
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Experimental Data
Lab Frame
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Neutral current nme? nme
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Note the following
? no interference between 1-g5 and 1g5
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Tricks
p?k , same!
1-g5 ? 1g5 equivalent to n?n or k?k ?
(pk)(pk) or s2?u2
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Compute (1g5) for e-
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Neutral current result nme? nme
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New Variable y
In Lab Frame (pme)
energy transferred incident energy

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nme? nme
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nme? nme
n? n same as 1-g5 ? 1g5 or gAe ? - gAe
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CHARM Experimental Data
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e
ne

gve? 1 gve gAe? 1 gAe
e
ne

(note Glashow resonance)
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n(n)e- SUMMARY
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Quark Mixing Matrix
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Quark Mixing Matrix contd
(Wolfenstein)
cos(qC)
sin(qC)
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CC n quark
n
pq
k
k
n
pq xP
and also
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CC DIS scattering
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Elastic CC n-N Scattering
e
n
k
p
W
p
k
ne
p
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Some details
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Cross section
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Precise Measurements
Flux and Energy Spectrum g 1-2
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CC Neutrino-disintegration of the Deuteron
d 3S1, T0
nn, pp 1S0, T1
MGT ltd S (st) NNgt
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Elastic CC n N scattering
FiV from e- scattering. FA from n scattering.
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Quasielastic scattering
Doppler Shift
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QE cross section
n0
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Electron Scattering
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Incident neutrino energy??
Neglect nucleon binding energy (25 MeV)
(HW)
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CC QE data compilation