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, 23 July - 3 August 2018, Beijing 1
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Flavor (American English) or flavour (British English; see
spelling differences) is the sensory impression of food or other
substance, and is determined primarily by the chemical senses of
taste and smell.
In particle physics, flavour or flavor refers to the species of
an elementary particle. The standard Model counts six flavours of
quarks and six flavours of leptons.
(must be written by an American)
(must be written by an European)
2
-
3
Matter ()
Flavor
-
4
Dirac + + /t
1/2
: Dirac
: E
,
:
-
t < ta : + e-
t = ta : e+ e-
t = tb : e+ e-
t > tb : + e-
5
-
1932: C. Anderson (V. Hess1936)
Cosmic rays in cloud chamber
1955: (Chamberlain and Segr1959)
6
-
7
-
AMS-02
AMS-011998 AMS-022011
10
-
11
C,P,T
Or +
+
+ a rotation
:
-
-
1956
12
-
:
z
LH
RH
C, P CP 13
RH
-
CP
Jrgen Beck Hansen Niels Bohr Institute 15
Charge conjugation and parity in weak interactions Particle
Physics
Neutral kaons
It is possible to produce the neutral kaons K0=ds and K0=sd in
p-collisions. This is a strong interaction process and strangeness
has to be conserved:
The kaons that are produced in this way are pure K0=ds and K0=sd
states.
However, K0 and K0 can be converted into each other since
strangeness is not conserved in weak interactions:
Example of a process converting K0 to K0.
p+ K0 +
+ p+ K0 p K ++ +
s: 0 0 +1 -1
s: 0 0 -1 0 +1
d s
s d
W+ W-K0 K0
u
u
S=+1 S=-1
CP
K
CP, KS 3KL 2
Cronin and Fitch1964
KL 2?
14
-
CPT :
A local, Lorenz invariant () theory with canonical
spin-statistics relation must be invariant with respect to
CPT-transformation
CPT
15
-
=
10 000 000 001
or 10 000 000 000
10 000 000 000
4%
16
-
17
Dirac
Dirac
-
Sakharov
A. Sakharov1967
CCP
Dirac
4He
CCP
18
-
CP
!=
CKM
19
align up and down type quarks
-
CKM
20
-
CPV in SM
21
-
CKM
22
CP
J/2
CP
-
The favorite triangle
23
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CP
A = a1ei(1+1) + a2e
i(2+2) A = a1ei(11) + a2e
i(22)
ACP =|A|2 |A|2
|A|2 + |A|2/ sin(1 2) sin(1 2)
CPCP
CP
24
+ a1 a2
a1 a2 a1 a2
-
CP CKMCP
JarlskogJ10-5
M100 GeV
10-17 , 10-10
CP 25
-
VS
:
GIM
K
CPV/CKM3
Z
:
CKM
26
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BaBarBelle
B2000
30
Why asymmetry energy and why these values?
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BESIII
21
BESIII
LINAC
: 2.0 4.6 GeV
LINAC
2016-12-14 21 31
-
18
BESIII Detector
Be beam pipe
SC magnetMuon Counter
Drift Chamber
CsI(Tl) calorimeter
TOF
32
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ATLASCMS
33
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LHCb detector Forward spectrometer @ collider, acceptance:
1.9
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Belle II detector
35
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:
:
:
:
:
Muon: (KL) muon
36
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CKM
37
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CKM
38
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QCD
39
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! ##$ CP
9
Two-body charmless B decays are central goal of LHCb physics.
Significant contribution of Penguin diagrams provides entry point
for New Physics
Direct CPV
Necessary condition: several interference contributions to one
decay
b
s
u
s
u
d
0sB
p +
K -
W +b
s
dW
u
u
s
p +
K -
0sB
g
0sB K p
- +
Vub ~ eig
40
Penguin diagram
CKM
-
41
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Extra words on CPV
42
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! ##$ CP
10
0B K p+ -0B K p- +
0sB K p
- + 0sB K p+ -
Benefit from excellent RICH for PID
LHCb, PRL 110 (2013) 221601
First observation of CPV in Bs system (2013)
%&' !( )*+, = /. ( (. 2 (. 3 %
%&' !5( ),+* = 62 7 8 %
43
B
-
B-
44
-
45
-
CP
46
For , Sf is sin2
, Cf ~ 0
, ~ 0
-
The next CPV?
-
CPCP
53
1995 2016 futureCKM
-
54
CPCP
-
55
Charge conjugation (C) Transfer a particle into
anti-particle
What changes: E, H, charge, baryon/lepton number, flavor charges
etc
What doesnt change: time-space, mass, momentum, spin etc
Normalisation:
Apply twice:
Hermitian: physically observable quantity
Eigenstates
Two fermions or bosons states:
Examples:
e+e-: (-1)L+S = -1 0: (-1)L+S = 1
C|bb >= (1)L+S |bb >
J/+-: (-1)L+S = -1 K+K-: (-1)L+S = -1
-
56
Parity (P,)
Or +
+
+ a rotation
Hermitian: physically observable quantity
Eigenvalues: 1 (except Majorana fermions)
Fermions and anti-fermions have different sign while bosons the
same
Examples:
e+e-: (-1)L(-1) = -1 0 (uu+dd)/sqrt(2): (-1)L(-1) = 1
J/+-: (-1)L(-1) = -1
Also in S-wave of cc
K+K-: (-1)L = -1
-
2
!(#)% '!(#)%
0 012 12
0 0
12 12
2 2
2 2
i iM MP Pdidt i iP PM M* *
- G - G = - G - G
d
B0 B0d
b
W Wtt
b
[DB=2]t
t
W W
00
00
= +
= -
H
L
P p P q P
P p P q P
(),+ -),+ ./ 0),+ = 2./ 0
45 26/
./ 06/
57
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PRD95, 2017
qGlobal fit prefers |Vcb|incl and |Vub|excl .
q Grinstein et al, suggest alternate FF fit (BGL) to recent
Belle BD*ln data.
q New BaBar analysis of |Vub|inclwith different HQE
extrapolation schemes (closer to |Vub|excl )
q Inclusive & exclusive mmentsconverging ? More data
needed!
BaBar
( )( )
3
2.0 31.9
37.4 1.3 10 [ CLN ]
41.9 10 [ BGL ]cb excl
cb excl
V
V
-
+ --
=
=
see also Gambino et al, 1703.06124
Grinstein et al, arXiv:1703.08170
Longstanding tension in Vub and Vcb
44 58
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Extra words on CPV
59
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602P 60Co
