quarks three families standard - theory iii ii i
TRANSCRIPT
STRONG FORCES
QUANTUM CHROMODYNA
MICS
bsd
tcu
NATURE: 6 QUARKS
quarks
three families
I
Standard - Theory
III
II
I
THREE FAMILIES
LEPTONS+
QUARKS
quarks only 45% of total momentum !
momentum
s s
s
electromagnetic decay neutral pion
triangle diagram - good agreement with experiment
0
factor 9 too small in decay rate
0
Electron-positron-annihilation Electron – positron - annihilation
3/2)3/1()3/1()3/2( 222 R
20
proton
quark model
23
color factor 3 in amplitude => experiment
0
23/23
))3/1()3/1()3/2((3 222
R
25
exact symmetry
SU(3)
lkiikl qqqbaryon
)( bbggrr qqqqqqmeson
color singlets
three dimensions
three colors
three families???????????????
Johannes Paul II
1985vatikan
QCDFritzsch / Gell-Mann
1972
8 massless gauge bosons
gluons
electrodynamics
q q
gluon
chromodynamics
Q E D
35
q
q
q
QCD
g g
gluons: 55% of total momentum !
gluons
FFqmieAiqL
4
1)(
aa
a
a
GGqmAigiqL4
1)
2(
e
137
1
4
2
e
quark
QCDgluon
4
2gs
cbabc
aaa AAgfAAG
aa
a
a
GGqmAigiqL4
1)
2(
2)( cbabc AAgf
46
222 /ln/2 QbQ os
fnb3
2110
MeV3835213
2
2
2
ln
4.1)(
QQs
0007.01184.0 Zs M
today:
q q
rkr
rrV s
)(
3
4)(
2/),( cquarksgluonsEM p
MeVconstM c _860.
elmssdduup cmcmcmccM
60
61
Feynman
e(-)e(+)
Elektron
Positron
Quark Antiquark
Meson Meson
e(-)e(+)
66
DESY - Hamburg
68
antibaryonqqq
baryonqqq
mesonqq
)(
)(
)(
...1)()(
...1)33()33(
33
33
qqqq
cuucge ..
RHIC
LHC
Large Hadron Collider LHC
Alice -Detektor
quark – gluon plasma
Big bang
electromagnetic interaction
Van-der-Waals force
atoms
molecules
strong interaction
nuclear force
mesons baryons
atomic nuclei
