7/29/2019 Introduction to hadron physics (one lecture)
1/55
Introduction to Hadron Physics
ZHENG Chuan
2011.5.5
7/29/2019 Introduction to hadron physics (one lecture)
2/55
Matter in nature
Track of Modern Physics
7/29/2019 Introduction to hadron physics (one lecture)
3/55
Where is mass from
proton
electron
hydrogen
me = 0.511 MeV/c2
mp = 938.3 MeV/c2
mu = 1.5 to 3.3 MeV/c2
md = 3.5 to 6.0 MeV/c2
1/1836
E = mc2 m = E/c2
px ~ & E = pcE ~ c/x = 197 MeVfm / 1 fm
Mass is from localization and field energy!
7/29/2019 Introduction to hadron physics (one lecture)
4/55
Strong force
Strong Electromagnetic Weak Gravitational
20 1 10-7 10-36
Two protons in nuclues
7/29/2019 Introduction to hadron physics (one lecture)
5/55
Nuclear force
Nuclear force: residual q-q interaction!
p
p
0p
p
p
n+/-
n
p
Yukawa firstly predicted the existence of mesons.
7/29/2019 Introduction to hadron physics (one lecture)
6/55
Bubble chamber
K- beam
e-
Liquid
hydrogen
Early tracking detector
7/29/2019 Introduction to hadron physics (one lecture)
7/55
K-
e-
Liquid
hydrogen
Bubble chamber
++
e+
7/29/2019 Introduction to hadron physics (one lecture)
8/55
K-
e-
Liquid
hydrogen
Bubble chamber
++
e+
ee
+ +
+
Meson +decay mode
7/29/2019 Introduction to hadron physics (one lecture)
9/55
Quark modelu
Q=+2/3
d
Q=-1/3
sQ=-1/3
s
Q=+1/3Q=-2/3
u d
Baryon: qqqMeson: qq
J P = 0- J P = (1/2)+
Hadron
7/29/2019 Introduction to hadron physics (one lecture)
10/55
Prediction of-
J P = (3/2)+
Liquid
hydrogen
K-
2e+
e-
-0
-
Baryon - was predicted by quark model.
7/29/2019 Introduction to hadron physics (one lecture)
11/55
Prediction of-
Liquid
hydrogen
K-
2e+
0--
e-+
+
+
+
+
Baryon - was predicted by quark model.
J P = (3/2)+
7/29/2019 Introduction to hadron physics (one lecture)
12/55
Prediction of-
Liquid
hydrogen
K-
2e+
e-
-0
0
0
0 0
2
K p K K
p
+
+ + +
+ + + + Barnes et al. PRL 12(1964)204
7/29/2019 Introduction to hadron physics (one lecture)
13/55
Force carrier
e-
e-
= e2/4 ~ 1/137q
q
q
q
g
sQCD (QuantumChromodynamics)
s
= gs
2/4 ~ 1
QED (QuantumElectrodynamics)
Charge of QED is electric charge.
Charge of QCD is called Colorwith 3 values
labelled red, greenand blue. -s ss
Gluon carry the charge
of the strong interaction!
7/29/2019 Introduction to hadron physics (one lecture)
14/55
Experimental evidence of quarksand gluons
7/29/2019 Introduction to hadron physics (one lecture)
15/55
Deep inelastic scattering
e-
Elastic scattering on spin 0
q2 = (k-k)2
Inelastic scattering on spin 1/2
Q2 >> 1 GeV2
22
Mott
2 3
d dF(q )
d d
F(q ) ( ) di q rr e r
=
=
i
i
2 2
22 1'
Mott
2' 2
1,2
F (Q , ) F(Q , )d d 2tand dE d 2 M
QE-E, x F (Q ,x)
2M
= +
= =
i i
Structure functions
7/29/2019 Introduction to hadron physics (one lecture)
16/55
Deep inelastic scattering
Nucleon is composed ofspin pointlike particles!
2 2
2 1
2 2
2
F (Q , x ) 2 x F (Q , x )
F (Q , x ) G (Q ) xf(x)
=
=
x: the fraction of the entireproton momentum carried
by the parton in nucleon
When x is fixed, F2 is thedipole form factor.
7/29/2019 Introduction to hadron physics (one lecture)
17/55
Quarks in e+e- annihilation
R =
e+
e-
+-
e+
e-
2 2 2 2 23
2 1 1 23 [( ) ( ) ( ) ( ) ...]
3 3 3 3i
i
Q= = + + + +
color u d s c
ss
cc
uu
bb
dd
211/310/3
7/29/2019 Introduction to hadron physics (one lecture)
18/55
Quarks in e+e- annihilation
R =
e+
e-
+-
e+
e-
2 2 2 2 23
2 1 1 23 [( ) ( ) ( ) ( ) ...]
3 3 3 3i
i
Q= = + + + +
color u d s c
ss
cc
uu
bb
dd
211/310/3
Proving the flavor and color properties of quarks!
7/29/2019 Introduction to hadron physics (one lecture)
19/55
Experimental evidence of gluons
Observation of 3-jets event in e+
e-
annihilation isthe direct experimental evidence of gluons!
7/29/2019 Introduction to hadron physics (one lecture)
20/55
QCD Theory of strong interaction
7/29/2019 Introduction to hadron physics (one lecture)
21/55
QCD Asymptotic freedom
0.8 fmEMV( )rr
= 4V( )3
sr k rr
= +
k ~ 1 GeV/fm
+ - q q
Asymptotic freedom is the most important featureof QCD!
7/29/2019 Introduction to hadron physics (one lecture)
22/55
QCD Asymptotic freedom
r ~ 1/Q small r
Strong coupling becomes less at smaller distance!
7/29/2019 Introduction to hadron physics (one lecture)
23/55
QCD Quark confinement
meson
baryon
All hadron states and physical observablesare color-singlets!
7/29/2019 Introduction to hadron physics (one lecture)
24/55
Chiral symmetry breaking
Left Right
u u
d d
22
( ) ( ) 10 MeVu d u dM
m m m m mf
= + +
( )
QCD gluon quark
quark
quark, ,
f fff
f u d u d
L L L
L q i D m q
L ui D u di D d m uu m dd
=
= +
= +
= + + +
Chiral symmetry
Quark mass
breakingmu
= md
= 0
Chiral symmetry is an approximate symmetryof strong interaction!
St d d d l
7/29/2019 Introduction to hadron physics (one lecture)
25/55
Standard model
7/29/2019 Introduction to hadron physics (one lecture)
26/55
Frontiers of hadron physics
Multiquark components
Quark Gluon Plasma
Exotic states
7/29/2019 Introduction to hadron physics (one lecture)
27/55
Hadron spectrum mesons
Very similar to electron configuration
JPC = 0-+, 0++, 1--, 1+-,
1++, 2++
JPC = 0--, 0+-, 1-+, 2+-
Allowed combinations
Not allowed: exotic
H d t l b ll
7/29/2019 Introduction to hadron physics (one lecture)
28/55
Hadron spectrum glueball
f0(980)
f0(1370)f0(1500)f0(1710)
Lattice QCD
Glueball
spectrum
q q
q q
g
g
g g Glueball is allowed in QCD!
Amsler Phys. Reports 389(2004)61
Hadron spectr m bar ons
7/29/2019 Introduction to hadron physics (one lecture)
29/55
Hadron spectrum - baryons
Baryon spectrum isless understood!
7/29/2019 Introduction to hadron physics (one lecture)
30/55
Hadron spectrum - multiquarks
Proton: |p> ~ |uud> +
1|[ud][ud]d> + 2|[ud][us]s> +
+KN
Nucleon has multiquark components?
PRL 91 (2003) 012002
2003-2004: 11 big accelerator labsreported Pentaquark findings, but 8other labs found no evidence of it.
The Pentaquark is not in goodhealth, but it is still alive!
Zou and Riska PRL 95 (2005) 072001
7/29/2019 Introduction to hadron physics (one lecture)
31/55
Internal structure of proton
Nucleon has multiquark components!
x
xf(x)
Phases of quark matter
7/29/2019 Introduction to hadron physics (one lecture)
32/55
Phases of quark matter
(Net Baryon Density)
Relativistic heavy
ions collision:
Au+Au Pb+Pb at 100 GeV/nucleon
(RHIC-STAR 2001)
at 1380 GeV/nucleon
(LHC-ALICE 2010)
To know the early universe after the Big Bang!
7/29/2019 Introduction to hadron physics (one lecture)
33/55
Particle detector
7/29/2019 Introduction to hadron physics (one lecture)
34/55
Principle of particle detecting
Tracking chamber (1)
7/29/2019 Introduction to hadron physics (one lecture)
35/55
Tracking chamber (1)
COSY-WASAMDC
Tracking chamber (2)
7/29/2019 Introduction to hadron physics (one lecture)
36/55
Tracking chamber (2)
0
2
4
6
8
10
12
14
E
MWPC
Drift
volume Charged
particl
etrack
Drifting electrons
from primary ionization
Drift field
Gating grid
Anode & Field wires
Cathode
Cathode
-HV
RHIC-STAR
TPC
7/29/2019 Introduction to hadron physics (one lecture)
37/55
Electromagnetic calorimeter (1)
CsI crystalX0 = 1.86 cm
L = 30 cm ; R = 5 cm
Yellow: Red: e+
Green: e-
7/29/2019 Introduction to hadron physics (one lecture)
38/55
Electromagnetic calorimeter (2)
beam
SLAC-Babar COSY-WASA
d i l i ( )
7/29/2019 Introduction to hadron physics (one lecture)
39/55
Hadronic calorimeter (1)
H d i l i (2)
7/29/2019 Introduction to hadron physics (one lecture)
40/55
Hadronic calorimeter (2)
IMP - Neutron Wall
P ti l id tifi ti
7/29/2019 Introduction to hadron physics (one lecture)
41/55
Particle identification
For long-lived charged particles!
2 2 22 2max
2 22 TdE 1 ln
dx 2 I
emcz
0P m c=
7/29/2019 Introduction to hadron physics (one lecture)
42/55
Invariant mass
Example:
0 ,
For short-lived resonant particles!
Minv2 = (E1 + E2)
2 (p1 +p2)2
Mi i
7/29/2019 Introduction to hadron physics (one lecture)
43/55
Missing mass
For the missed particles in the detection!
Example: pd3He X
MX2 = (Ep + md - EHe)
2 (pp - pHe)2
beam target beam
(782)
7/29/2019 Introduction to hadron physics (one lecture)
44/55
Experimental facility
Accelerator
7/29/2019 Introduction to hadron physics (one lecture)
45/55
Accelerator
CERNSynchrotrons
SLAC (Standford
Linear ACcelerator)
Linear and Ring shape!
COoler SYnchrotron (J uelich)
7/29/2019 Introduction to hadron physics (one lecture)
46/55
COoler SYnchrotron (J uelich)
COSY in ~1993
COSY (Cooler Synchrotron)
Circumference 184 m
Beam
(polarized and unpol.)
Proton
/deuteron
Luminosity
(cluster, pellet target)
~1031 cm-2s-1
Beam lifetime a few minutes
to an hour
Beam momentum 0.3 3.7
GeV/c
Intensity (particles) 1010 - 1011
Preparation time a few seconds
HIRFL CSR (Lanzhou)
7/29/2019 Introduction to hadron physics (one lecture)
47/55
CSRm:1.1 AGeV(12C6+)
CSRe:0.76 AGeV (12C6+)
SFC:up to 10 AMeV
SSC:up to 100 AMeV
CSRm:up to 2.8 GeV
proton beam forHadron Physics
HIRFL-CSR (Lanzhou)
HIRFL CSR (Lanzhou)
7/29/2019 Introduction to hadron physics (one lecture)
48/55
HIRFL-CSR (Lanzhou)CSRe
CSRm
Giant detectors at LHC
7/29/2019 Introduction to hadron physics (one lecture)
49/55
Giant detectors at LHC
WASA (J uelich)
7/29/2019 Introduction to hadron physics (one lecture)
50/55
WASA (J uelich)
Detector has the similar layer structure,no matter its big or small!
WASA (J uelich)
7/29/2019 Introduction to hadron physics (one lecture)
51/55
WASA (J uelich)
Superconducting solenoid
HPLUS (Lanzhou)
7/29/2019 Introduction to hadron physics (one lecture)
52/55
HPLUS (Lanzhou)
beam
p/d frozen-pellet target
Detector simulation
7/29/2019 Introduction to hadron physics (one lecture)
53/55
Detector simulation
DAQ and Data
7/29/2019 Introduction to hadron physics (one lecture)
54/55
WASADAQ system
Total channels: 3630; Data rate: 3~4 TB/day!
Summary
7/29/2019 Introduction to hadron physics (one lecture)
55/55
Summary
Quarks and gluons are in reality.
Quantum ChromoDynamics is the basictheory of the strong interaction.
Hadron spectrum, the internal structure of
nucleon and the phases of QCD are thefrontiers of hadron physics.
Particle detectors are the experimentaltools which have similar layer structure.
Big experiment needs big collaboration.
Top Related