Transcript 投影片 1 - Nanyang Technological University

Why Pursue the Fourth Generation Still ?
January 30, 2012, 1st IAS-CERN SCHOOL @ NTUSG
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 1
Outline
I.
Intro:
Capri’08; 1st BSM3 & 4 Statements; Summer’11 ...
II. Breaking the Unitarity “Bound”
3-2-1/No-New-Physics; Higgs Saga; Strong WW vs Strong QQ
III. Yukawa Bound States: Issues and Pheno
Yukawa from Gauge; Yukawa-bound “Mesons”; Pheno Detour
IV. A Postulate & A Gap Equation without Higgs
V.
From Hints to Measurements: Indirect/Direct
Bs → J/yf / Bs → mm / B → K*mm║ mt ; BR(t → b W*)
VI. Conclusion
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 2
I. Intro
arXiv:0805.4393 [hep-ph]
CPV
George W.S. Hou (NTU)
NCU, Oct 6, 2009 3
~ 149 citations today
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 4
sin2FBs ~ -0.5 - -0.7
WSH, Nagashima, Soddu, PRD’07
(already in 05)
sin2FBs ~ -0.33
WSH, Ma, arXiv:1004.2186 [hep-ph]
Also, Soni et al., arXiv:1002.0595 [hep-ph]
Buras et al. arXiv:1002.2126 [hep-ph]
Lenz et al., arXiv:1005.3505 [hep-ph]
4th generation “prediction” still robust, but needs LHCb to verify.
curios
1.2s too
Fourth Generation
George W.S. Hou (NTU)
TOP2010, Bruges, 100603 5
B Physics Results from the LHC Gerhard Raven
LP11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 6
CPV
George W.S. Hou (NTU)
NCU, Oct 6, 2009 7
highlighting is mine
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 8
So, why 4G still ?
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 9
II. Breaking the Unitarity “Bound”
1-2-3/No-New-Physics; Higgs Saga;
Strong WW vs Strong QQ
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 10
Nobody Saw Anything New Anyway
Celebration: 5 fb-1 @ LHC 7 TeV in 2011 !
Apprehension: No-New-Physics !!
1-2-3 of 2011
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 11
Michael Peskin at LP11
Our field seems to be approaching a definite point of reckoning.
But will it lead us to enlightenment, or to disillusionment and
chaos ?
Confutatis maledictis,
flammis acribus addictis,
voca me cum benedictus.
When the accursed are confounded,
and doomed to flames of woe,
Call me among the Blessed.
and that prayer goes for Everyone ...
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 12
Higgs Saga: July => August
ATLAS
EPS
CMS
LP
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 13
Higgs Saga: December 13, 2011
not better than old 144 ...
We do not have any firm experimental knowledge
that the Higgs boson even exists.
Will 125 GeV survive ?
(EW S, T variables)
CMS ’11 prelim.
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 14
b' Search @ LHC
_
b' (→ W- t) b'
PLB 11
Partial Wave Unitarity Bound
LP11
Will cross UB w/ 2011-2012 data
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 15
Higgs Saga: December 13, 2011
not better than old 144 ...
We do not have any firm experimental knowledge
that the Higgs boson even exists.
Will 125 GeV survive ?
(EW S, T variables)
CMS ’11 prelim.
Theme: Can Strong Yukawa Coupling generate EWSB itself ?
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 16
III. Yukawa Bound States: Issues and Pheno
Yukawa Coupling from Gauge Coupling;
Yukawa-bound Mesons: Bethe-Salpeter vs Rel. Exp.;
Detour into “Intermediate Mass” Pheno
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 17
From Gauge to Yukawa Couplings
Experimental Facts:
• q & l pointlike to 10-18 m
Governed by
•
==> SSB
• All fermions Massive ==> EWSB as well
Elementary Higgs Not yet a Fact
Theoretical Foundation: Renormalizability of Gauge Theories
Proof based on Ward Identities, unaffected by SSB.
’t Hooft. 1972
Existence of Yukawa Couplings an Experimental Fact !
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 18
Unitary Gauge (no scalar particles)
Eq. of Motion (known massive)
Yukawa Coupling from Purely Left-handed Gauge: Goldstone
Coupling
N.B. KM and Flavor/CPV data provide further evidence for Yukawa Dynamics, yet again No Higgs.
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 19
Bethe-Salpeter approach to new Heavy Isospin
Jain et al., PRD 92; 94
semi-degenerate
Isosinglet 1- lightest
↬ Collapse
r1
for large mQ
w1
w1
various
approx. solutions
±
+
p1 becomes most attractive!
r1
±
but s-channel is repulsive !
+
Ishiwata & Wise, PRD 11
relativistic correction study
breaks down ?
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 20
Fourth Generation Bound States
relativistic expansion study
g (, H)
w1
r1
breaks down ?
My interpretation:
• QCD-bound for GeV scale binding energy
• Sudden turn-on of Large Yukawa Coupling
⇒ Sudden drop in radius, jump in binding
• Rel. v/c Expan. fails just when it turns interesting.
accidental degeneracy
w8
p8
r8
less bound
Ishiwata and Wise, PRD 11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 21
p1
: “usual”
:
Goes down fast w/ mQ
Bethe-Salpeter “potential”
Yukawa / g5
• Tight, Relativistic Bound State (large q!)
• “Negative Energy Potential” Matters!
• What does collapse mean? What about s-channel subtr.?
Enkhbat, WSH, Yokoya, PRD’11
4G Still ?
George W.S. Hou (NTUTW)
deep boundstate production/decay …
IAS-CERN-1@NTUSG 1/30/2012 22
Detour
“Intermediate Mass” Yukawa BoundState Pheno
Enkhbat, WSH, Yokoya, PRD’11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 23
mQ = 500 – 700 GeV; binding -100 to -200 GeV
do not touch
collapse yet
“Intermediate Mass”
1 to 1.4 TeV
no gg production
(Yang’s Thm)
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 24
Decay
tantalizing signature
nominal
no annihilation decay
narrow
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 25
“Intermediate
Mass” range
Results
small
decay constant
dijet
large
mass difference
4G Still ?
subdued !
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 26
from the Abstract
Enkhbat, WSH, Yokoya, PRD’11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 27
IV. A Postulate & A Gap Equation without Higgs
A Postulate: Collapsed QQ as Goldstone;
A Bootstrap Gap Eq. w/o Higgs;
Discussion & Lattice future
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG
to appear CJP
1/30/2012 28
Bethe-Salpeter approach to new Heavy Isospin
Jain et al., PRD 92; 94
semi-degenerate
h1
Isotriplet
lightest
Isosinglet 10- lightest
↬ Collapse
w1
w1
p1 ± ±
p1
+
r1
+
r1
±
cov.
for
largemmQQ
for large
+
but s-channel is repulsive !
+± h1
George Hou’s Postulate #1: p1 =
Unfinished Yuk.
p1 becomes MAC !
Ishiwata & Wise, Goldstone
PRD 11
G relativistic correctionasstudy
Collapsed
breaks down
? QQ
to appear CJP
George W.S. Hou (NTU)
VHQWS, Taipei, 1/20 ’12 29
Gap Equation without Higgs
Disc. w/ Felipe Llanes Estrada, 7/2010
Disc. w/ Enkhbat
and Yokoya, 1/2011
Tight and Tiny
Self Energy !
“Empirical”
Can one form Gap Eq.?
• Got Mimura interested (since 4/2011)
• Asked Kohyama to check vs NJL (since 1/2011)
• Literature:
- Maskawa et al. ’70s
- Higashijima ’84
- Fukuda & Kugo ’76
G = p1
talk 1/26
• Bingo: finally read Hung & Xiong ’11, recently
- Almost same Eq., with G replaced by
up to almost 2mQ
ad hoc
massless H-doublet
- Follow Fukuda-Kugo/Leung-Love-Bardeen
Numerical Guess:
“Strongly-coupled Scale-Inv. QED”
==> Dynamical Chiral Symmetry Breaking
- Idiosyncrasy on UV fixed-point
Goldstone
as
• Integral Eq. ==> DEq. + B.C.
Will study with Mimura and Kohyama (maybe Kohda?)
Unfinished Yuk.
George W.S. Hou (NTU)
Collapsed
QQ
to appear
CJP
VHQWS, Taipei, 1/20 ’12 30
Discussion
• We adhered to Empirical/Heuristic Approach
• Yukawa-bound “mesons” might collapse
==> Postulate that Goldstone is MAC
Look mom, no hands!
p1 = G
Higgs
• Simple Gap Eq. ~ Strong Scale-inv. QED
- vs. NJL: No 4Q-operator assumed.
Instead, tightly bound Goldstone.
- vs. QCD/TC: Q is Not Confined !
Pion of QCD a Stringy state;
here, yet unknown ― Theory of Yukawa Coupling
• Experimental View:
From 1-2-3/No-New-Physics, no objects @ v.e.v.
- Gap Eq. seem to sum up all dominant effect
- VL = G may be the only “portal” to New Physics,
other than direct production of heavy Q pair.
Origin of EWSB:
==> Strongly Coupled Higgs Sector
⊕
to appear CJP
Unfinished Yuk.
George W.S. Hou (NTU)
VHQWS, Taipei, 1/20 ’12 31
Lattice: only known nonpert. approach
talk at Lattice 2011
Last name: Lin
First name: C.-J. David
Affiliation: National Chiao-Tung University
Email address: [email protected]
Title: Study of the Higgs-Yukawa Theory at the Strong-Yukawa Regime
Authors: John Bulava, Philipp Gerhold, George W.-S. Hou, Karl Jansen,
C.-J. David Lin, Kei-Ichi Nagai, Attila Nagy, Kenji Ogawa,
Brian Smigielski
Type: Parallel
Session: Applications beyond QCD
Abstract:
We present an on-going project on the Higgs-Yukawa theory in the
regime of large bare Yukawa coupling. We use the overlap fermion and
the pHMC algorithm in this work. Our preliminary study shows that there
exists a symmetric phase (vanishing scalar vacuum expectation value) in
this regime. We also comment on the investigation of the spectrum.
work in progress
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 32
Vt b
i fsb

Vt sVt b  rsb e
V. From Hints to Measurements: Indirect/Direct
Measuring CKM4 Solely @ LHC
t, t ’
Vt sVtb
,
t’
Vt sVtb t, t ’
4G Still ?
WSH, Kohda, Xu, PRD’11
Chao et al., PRD’11
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 33
Andrei: Do you like the 1 fb-1 number I gave, George?
George: Ya, but perhaps -0.3  0.1 better
fs ~ -0.83
[sinfs ~ -0.74]
4G Still ?
Andrei Golutvin @
George W.S. Hou (NTUTW)
Resources Review Board
IAS-CERN-1@NTUSG 1/30/2012 34
sin2FBs ~ -0.5 - -0.7
WSH, Nagashima, Soddu, PRD’07
(already in 05)
sin2FBs ~ -0.33
WSH, Ma, arXiv:1004.2186 [hep-ph]
Also, Soni et al., arXiv:1002.0595 [hep-ph]
Buras et al. arXiv:1002.2126 [hep-ph]
Lenz et al., arXiv:1005.3505 [hep-ph]
4th generation “prediction” still robust, but needs LHCb to verify.
curios
1.2s too
Fourth Generation
George W.S. Hou (NTU)
TOP2010, Bruges, 100603 35
B Physics Results from the LHC Gerhard Raven
LP11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 36
7.0  2.4 x 10-9
reachable w/ 1 fb-1 ?
◀
Add ATLAS/CMS !
Andrei Golutvin
4G Still ?
George W.S. Hou (NTUTW)
CERN RRB April 2011
IAS-CERN-1@NTUSG 1/30/2012 37
B Physics Results from the LHC Gerhard Raven
LP11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 38
Measuring CKM4 Solely @ LHC

V
V
t, t ’ t s t b
Vt sVtb
t, t ’
SM3
t 
“classic”
SM3
Bs
,
t’
Vt sVtb
4G Still ?
Remove
Trick: Take Ratio of
Bs → m+m- and Dms
George W.S. Hou (NTUTW)
only
dependence,
left.
IAS-CERN-1@NTUSG 1/30/2012 39
Measuring CKM4 Solely @ LHC
Anticipating 2012

V
V
t, t ’ t s t b
Vt sVtb
t, t ’
“2s” from 2011
Bs
SM3-like
,
t’
Vt sVtb
4G Still ?
Could be smaller than SM3
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 40
i fsb

Vt sVt b  rsb e
Anticipating 2012
“2s” from 2011
SM3-like
for mt’ = 550 GeV
~ Enhanced
~ Below SM3
Intersect at ~ SM3 value
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 41
i fsb

Vt sVt b  rsb e
A Third Measureable: AFB
| Vt sVtb |  0.008
for mt’ = 550 GeV
Contours of
~ SM3 !
x
x
Sample points: blue; purple;
red; green.
Allowed
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 42
i fsb

Vt sVt b  rsb e
| Vt sVtb |  0.008
for mt’ = 550 GeV
WSH, Kohda, Xu, PRD’11
The refined measurements of
˙ sin2FBs
˙ B (Bs → m+m-)
˙ A FB (B0 → K*0m+m-)
together with mt’, will pinpoint
the value of
Vt sVtb
Take red point to illustrate the
Meaning.
Sample points: blue; purple;
red; green.
Allowed
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 43
Vts Vt b
O
 0.0065 e
i 70 
Belle/BaBar Measurement

VudVub

VusVub
 rsb e
ifsb
[Yamauchi talk]
b→d

VcsVcb
S
VtsVtb |SM

- Vcd Vcb
b→s
VtsVtb
Measurement of
t, t ’
KM Nobel
Vt sVtb
Vt sVtb
,
t’
Vt sVtb t, t ’
A FB (B0 → K*0m+m-) as crosscheck
Determine (knowing t’ mass) ~ Triangle Relevant for BAU?
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 44
CPV
George W.S. Hou (NTU)
NCU, Oct 6, 2009 45
but TCPV hint is now diminished …
so then
phase space suppressed
virtual
vs
CKM suppressed
t, b
Threshold enhanced
determination of CKM4
Vt b
Vt b
BR(b → t W*)
determines Vt b
Y. Chao et al., PRD 11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 46
VI. Conclusion
• Measure CKM4 relevant (?) for BAU at LHC [measure also BR(t → b W*)
• nEDM4 safe; BAU4 “possible”
[slides in backup
• Unitarity Bound approached with 2011-2012 LHC Data
Ultra Relativistic, Strong/Nonpert. BoundStates !?
• Postulate that VL (G) is tight QQ Boundstate
A “Bootstrap” Gap Eq. for EWSB via Strong Yukawa ?
• Need Lattice Study/Understanding to Go Beyond
Aug to Dec, 2012
Transition ~ Moriond / Summer Conf. 2013
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 47
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 48
:)
Forecast in 2009
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 49
Strategizing NTUCMS
ca. early 2006
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 50
Strategic Planning for CMS Physics Analysis
Vision ~ Early ’06
4th generation? —
The jury is out …
In era of LHC, can Directly Search for b’, t’
Once and For All !
Find b’, t’, or Rule Out @ LHC
It’s a Duty.
Strategy Considerations (
)
• Well shielded training ground — All Tools
☞ Move on to Greener Pastures ~ in 2 years
• Publish early — Large Cross Section
- If “Limits”, then easy to publish
- If “Signal”, Lucked Out!
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 51
Enhancing Small Numbers
nEDM4 and BAU4
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 52
New neutron EDM expts underway …
» for BAU «
nEDM4
4G Still ?
George W.S. Hou (NTUTW)
Borderline even if
3
hadronic enhanced by
53 10
IAS-CERN-1@NTUSG 1/30/2012 53
nEDM4 estimate
Pospelov & Ritz, PRD’01
effective 3-loop estimate, picking out large momenta in loop
Hamzaoui & Pospelov, PLB’95
Hamzaoui & Pospelov, PRD’96
Hou & Ma, PRD’10
nEDM4 ~ 10-31 e cm
nEDM is a slow (safe) track for 4G
w/ Fanrong Xu & Junji Hisano, PRD’11
4G Still ?
George W.S. Hou (NTUTW)
IAS-CERN-1@NTUSG 1/30/2012 54
BAU4 estimate
bubble wall
• Farrar & Shaposhnikov claimed, in 1993, that SM3 could generate BAU by
CP violating scattering of quasi-particles (thermal excitations of q & anti-q)
with bubbles of the
Higgs condensate
• This was shot down by Gavela, Hernández, Orloff and Pène in 1994, who
pointed out FS neglected the damping length in the plasma (mainly QCD)
• Huet & Sather gave in PRD’95 a lucid account, finding conservatively
• We find, following the steps of HS,
seem sufficient !
Problem: Large Yukawa coupling.
4G Still ?
George W.S. Hou (NTUTW)
w/ Masaya Kohda & Yoshio Kikukawa (prelim.)
IAS-CERN-1@NTUSG 1/30/2012 55