Transcript BABAR Status & Plans David B. MacFarlane SLAC EPAC Meeting January 25, 2006

BABAR Status & Plans
David B. MacFarlane
SLAC EPAC Meeting
January 25, 2006
Pillars of BABAR physics program
 Highly constrained and redundant set of precision
tests of weak interactions in the Standard Model
o Full program of flavor physics/CP violation measurements
will provide a legacy of fundamental constraints on future
New Physics discoveries
 Searches for physics beyond the Standard Model in
a well understood & characterized environment
o Sensitivity to New Physics at LHC mass scales through
rare decays and CP violation
o Discovery potential from large data sample across a whole
range of beauty, charm, tau, two-photon, ISR physics
Challenging measurements at the edge of sensitivity benefit
enormously from operation of both PEP-II & KEK B Factories
Jan 25, 2006
BABAR Status and Plans
2
The BABAR
Collaboration
11 Countries
80 Institutions
623 Physicists
Jan 25, 2006
BABAR Status and Plans
3
BABAR & Belle physics results
BaBar
200
Belle
150
100
50
Journal Papers
Jan 25, 2006
Jan-05
Jan-04
Jan-03
Jan-02
Jan-01
0
BABAR
Belle
184
155
BABAR Status and Plans
4
Integrated data sample to date
96% efficiency over the
entire history of BABAR
BABAR, Run 5
Jan 25, 2006
BABAR Status and Plans
5
PEP-II overall parameters and goals
Parameter
Units
Design
Oct 2005
I+
mA
2140
2940
I-
mA
750
1740
1658
1732
Number of
bunches
by*
mm
15-20
11
Bunch length
mm
15
11-12
0.03
0.0440.065
xy
Luminosity
x1033
3.0
10.0
More than 3x design
Int lumi / day
pb-1
130
727.8
More than 5x design
Jan 25, 2006
BABAR Status and Plans
6
PEP-II overall parameters and goals
Parameter
Units
Design
Oct 2005
2007 goal
I+
mA
2140
2940
4000
I-
mA
750
1740
2200
1658
1732
1732
Number of
bunches
by*
mm
15-20
11
8-8.5
Bunch length
mm
15
11-12
8.5-9
0.03
0.0440.065
0.0540.07
xy
Luminosity
x1033
3.0
10.0
20
Int lumi / day
pb-1
130
727.8
1300
40%
30%
10%
Factor 2!
Jan 25, 2006
BABAR Status and Plans
7
Integrated Luminosity [fb-1]
Projected data sample growth
1200
Double again from 20
2006 to 2008
ICHEP08
1000
800
o PEP-II: IR-2
vacuum, 2xrf
stations, BPM
work, feedback
systems
o BABAR: LST
installation
17
600
Double from
2004 to 2006
400
12
ICHEP06
Lpeak = 9x1033
4-month down for LCLS,
PEP-II & BABAR
200
Jan 25, 2006
BABAR Status and Plans
Jul-08
Jul-07
Jul-06
Jul-05
Jul-04
Jul-03
Jul-02
Jul-01
Jul-00
Jul-99
0
8
IFR upgrade with LSTs
Bottom & top sextants installed summer 2004
Remaining sextants delayed until fall 2006
Jan 25, 2006
BABAR Status and Plans
9
Weak Interaction in Standard Model
Unitarity Triangle as a summary
of Standard Model b physics
Unitarity: VudVub* VcdVcb* VtdVtb*  0

(b  u  )
0, 0
Jan 25, 2006
Vud
V  Vcd
V
 td
Vus
Vcs
Vts
Vub 
Vcb 
Vtb 
+ phases
Apex at
 ,  
Radiative penguin decays
B 0 - B 0 mixing
 B and ( b  c  )
BABAR Status and Plans
1, 0 
10
Classic indirect constraints
Vub
md
Jan 25, 2006
2008: ~5%
K
ms
BABAR Status and Plans
11
Weak Interaction in Standard Model
Unitarity Triangle as a summary
of Standard Model b physics
Unitarity: VudVub* VcdVcb* VtdVtb*  0

(b  u  )
Apex at
 ,  
  2
0, 0
Jan 25, 2006
Vus
Vcs
Vts
Vub 
Vcb 
Vtb 
+ phases
CKM elements & quark masses are
fundamental constants emerging
from EW symmetry breaking
Radiative penguin decays
CP violation
  3
Vud
V  Vcd
V
 td
b  1
 B and ( b  c  )
BABAR Status and Plans
B 0 - B 0 mixing
1, 0 
12
CPV in charmonium modes

  , 
  2
(b  u  )
  3
0, 0
B 0 -B 0
mixing
b  1
 B and ( b  c  )
CPV in B 0  J / KS0
1, 0 
Interference of b  c tree
decay with mixing
W
B0
BABAR Status and Plans
s
K
d
d
b
B0
Jan 25, 2006
c
c J /
b
d
W
t
t
0
d
W
b
B0
13
CPV in charmless modes

  , 
  2
(b  u  )
  3
0, 0
3rd component:
sizable Penguin
diagram
CPV in B 0 
 ,  , ,
b  1
 B and ( b  c  )
B 0 -B 0
mixing
u 
d
d
u

d
u

W
b
B d
0
d
b
B0
BABAR Status and Plans
d


u
u ,c ,t g
B0
1, 0 
Interference of suppressed
b  u tree decay with mixing
Jan 25, 2006
W
b
d
W
t
t

d
W
b
B0
14
Remarkably good progress on gamma!

  2
(b  u  )
u
B -B
mixing
0
  3
0, 0
Effect depends on
ratio of two diagrams
  , 
b  1
 B and ( b  c  )
0
1, 0 
 : CPV in B 0  DCP K , DDCS K ,
Interference of color-allowed and
color-suppressed tree decays
Jan 25, 2006
BABAR Status and Plans
b
B u
W

B
W
u
s
c
u
b


K (*) 
D (*)0
u (*)0
cD
s (*) 
K
u
D (D ) decay to
common final state
DCP , DDCS , D 0  KS0  
15
Direct CP violation measurements
2008: ~2%
2008: 10o

sin2b

2008: 5-10o
Jan 25, 2006
cos2 b
BABAR Status and Plans
16
UT from sin2b & indirect constraints
Overconstrained:
growing set of
independent
measurements are
consistent with
CKM picture
Paradigm change!
Jan 25, 2006
BABAR Status and Plans
Now: looking for
New Physics as
correction to CKM
17
UT from CP violation measurements alone
New B Factory
milestone: Comparable
UT precision from
CPV in B decays alone
Overconstrained: subsets
of measurements can be
used to test for new
physics
Jan 25, 2006
BABAR Status and Plans
18
CPV in Penguin Modes

  , 
  2
(b  u  )
  3
0, 0
Another implication of
overconstrained: redundant
approaches to same CKM
parameter
B 0 -B 0
mixing
b  1
 B and ( b  c  )
CPV in B 0  KS0 ,  KS0 ,
1, 0 
s
s
W
b
u ,c ,t g
B0
s K
d
d
Interference of suppressed
b  s Penguin decay with mixing
Jan 25, 2006
BABAR Status and Plans
b
B0
d
W
t
t

0
d
W
b
B0
19
Potential New Physics contributions
B 0  K 0
W
New physics in loops?
u , c ,t
b
B
d
s 
s
0g
s K0
d S
b
B
d
Jan 25, 2006

s
KS0
d
SUSY contribution with
new phases
B 0   K 0
B0
s
0
“Internal Penguin”
s


b
KS
0
B
s
s
0
d
BABAR Status and Plans

s
KS0
d
20
Revealing new physics
B Factory
LHC
Squark mass matrix (d sector)
Jan 25, 2006
BABAR Status and Plans
21
Summary after summer 2005 updates
Charmonium
s-Penguins
BABAR : 237 million BB pairs
Belle: 386 million BB pairs
Summer 05 results
2.4s between CP
violation in s-penguin
vs sin2b (cc)
No sign of Direct CP
About 0.5s loss vs Winter
2005 due to shift in
charmonium average
Jan 25, 2006
BABAR Status and Plans
22
BABAR CKM physics goals
Physics
Impact
Precision measurement
of sin2b
Fundamental constant of the SM,
whose precision is only limited
by statistics
Improve error
by factor of
two to 2%
Precision measurement
of CP asymmetry in
b  sqq penguin modes
Primary approach to new physics Potentially
in loop decays; b  sss presently reach the 4-5s
discrepant with SM predictions at level for
2.4s level when averaged over
average of all
b  sss modes
all available modes
Could reach
the 4-5s level
for individual
theoreticallyclean modes
Precision measurement
of unitarity angle 
Fundamental constraint on the
UT
Precision measurement
of unitarity angle 
Fundamental tree-level constraint
on phases and amplitudes
originating from any new physics
beyond the SM
Pioneering
measurements
with 10-15o
accuracy
Determine to
5-10o precision
Precision measurement
of Vub with inclusive &
exclusive semileptonc B
meson decays
Fundamental tree-level constraint
on amplitudes and phases
originating from any new physics
beyond the SM
Inclusive
decays reach
6.5% precision
Exclusive
decays reach
8% precision
Jan 25, 2006
FY2006
450 fb-1
FY2007
650 fb-1
Discovery of
B0   0  0 if
it has SM
branching
fraction
BABAR Status and Plans
FY2008
1000 fb-1
Isospin
analysis in
B   allows
better than 10o
measurement
23
Global CKM fit: 2008
s (Vub )  6.5%
Jan 25, 2006
s (ms )  5%
95% contours
s (sin 2b )  0.019 s ( )  8o s ( )  10o
BABAR Status and Plans
24
Projections to summer 2008
0.40
s (S )  0.30
0.30
Luminosity
expectations
:
2004=240 fb-1
2008=1.0 ab-1
K*
0.25
0.20
f0KS
KS0
jKS
’KS
KKKS
0.15
Projections are statistical errors only;
but systematic errors at few percent level
Jan 25, 2006
BABAR Status and Plans
Jul-09
Jul-08
Jan-08
Jul-07
Jan-07
Jul-06
Jan-06
Jul-05
Jan-05
Jan-04
Jul-03
0.00
5s discovery region if non-SM
physics is 0.30 effect
2004
2008
Jul-04
0.05
Jan-09
0.10
Jan-03
Error on sine amplitude
0.35
Golden modes
reach 5
sigma level
25
UT constraints in 2008
now
95% contours
2008
s (Vub )  8%
s (Vub )  6.5%
Assumption: no NP in trees [almost any NP model]
Significant constraint on all New Physics models in LHC era
Jan 25, 2006
BABAR Status and Plans
26
Bounds on new physics in Bd mixing
Introduce new physics
in mixing diagram
 MBd   CBd  MBd
now

SM
ACP J / KS0   sin2  b  Bd

Mass scale being
probed for unit
coupling:
2008
L(now) ~ 5 TeV
L(2008) ~ 10TeV
Model independent
Jan 25, 2006
BABAR Status and Plans
27
BABAR rare decay physics goals
Physics
Impact
FY2006
450 fb-1
FY2007
650 fb-1
FY2008
1000 fb-1
Discovery of
B 
Provides a determination of
Vub and constrains Higgs sector
in MSSM and NP in a parameter
regime that is complementary to
LHC
Limit
First hints
Discovery if it
has SM
branching
fraction
Precision determination
of b  s branching
fraction, CP asymmetry,
and photon energy
spectrum
Loop diagram that provides
unique insight into B meson
structure and constrains Higgs
sector in MSSM and NP in a
parameter regime that is
complementary to LHC
Ultimate
precision on
photon energy
spectrum
Strong
constraints
from 5% error
on BF; 1-2%
error on CP
asymmetry
Precision determination
of b  s   branching
fractions, CP and FB
asymmetries
Contributions from Z-penguin
and W-exchange loops that give
additional constraints on MSSM
and NP in a parameter regime
that is complementary to LHC
Useful
precision for
constraints on
NP
Provides a unique determination
of CKM matrix elements
Vtd / Vts ; likely before
BS0 -BS0 mixing discovery
First hints
Discovery of B  
Jan 25, 2006
BABAR Status and Plans
Strong
constraint for
NP from BF,
CP and FB
asymmetries
Discovery if it
has SM
branching
fraction
Precise
measurement
of BF
28
New CKM constraints in sight
b
u
W,H


2008: Possible discovery

W
b
t
d
Possible discovery: 2007
B  
B  
Jan 25, 2006
BABAR Status and Plans
29
Complementarity with LHC
2008
today
Approx…
2HDM
Constraints from B , B s
Jan 25, 2006
BABAR Status and Plans
30
BABAR Physics Goals
Physics
Impact
FY2006
450 fb-1
Search for D0 -D0 mixing
Highly suppressed in the SM and
therefore an ideal place to search
for new physics in charm mixing
diagram
Hint if 1%
mixing
amplitude
Search for lepton-flavor
violation in   
or other tau decays
Expected to be significantly
enhanced in many extensions of
the SM accommodating neutrino
mass, but extremely small in the
SM itself
New discovery in heavy
hadron spectroscopy
Improved understanding of QCD
in non-perturbative regime
Jan 25, 2006
FY2007
650 fb-1
FY2008
1000 fb-1
Discovery if
1% mixing
amplitude
Limits reach
2x10-8
sensitivity
Discoveries
possible
anytime
BABAR Status and Plans
Discoveries
possible
anytime
Discoveries
possible
anytime
31
Lepton-flavor violation & mSUGRA




tanb= 55
Inverted hierarchy
Br(e) < 1x10-8
5x10-8 2x10-8
11x10-8
2008 limit
Current BABAR limit
Jan 25, 2006
BABAR Status and Plans
32
Summary: Physics plans for BABAR
 Goal for 2005-2006: double current data set
o
o
Delay in Run 5 can be overcome by summer 2006 with extended
running period, with substantial reduction in errors on CP
violation asymmetries in rare decay modes
Error on average of Penguin modes should reach 0.06
 Goal for 2007-2008: double again to ~1 ab-1
o
o
Individual Penguin modes with errors in range 0.06-0.12
Suite of fundamental Standard Model measurements with
substantially improved levels of precision
o Sensitivity to New Physics through rare decays, CP violation, &
large data sample with a significant discovery potential
o Full program of flavor physics/CP violation measurements provide
fundamental constraints on future New Physics discoveries
 Beyond 2008 might offer exciting opportunities if
New Physics has been seen by B Factories & LHC
Jan 25, 2006
BABAR Status and Plans
33
Backup Slides
A day in the life of a B Factory
Jan 25, 2006
BABAR Status and Plans
35
PEP-II performance: peak luminosity
12
Peak PEP-II Luminosity (x1E33) per Month
10
8
6
4
2
Jan 25, 2006
BABAR Status and Plans
Dec-05
Jun-05
Dec-04
Jun-04
Dec-03
Jun-03
Dec-02
Jun-02
Dec-01
Jun-01
Dec-00
Jun-00
Dec-99
Jun-99
0
36
BABAR Detector
EMC
6580 CsI(Tl) crystals
1.5T
solenoid
e (3.1GeV)
DIRC PID)
144 quartz bars
11000 PMs
Drift Chamber
40 layers
e (9GeV)
Instrumented Flux Return
Iron / Resistive Plate
Chambers or Limited
Streamer Tubes (muon /
neutral hadrons)
Jan 25, 2006
Silicon Vertex Tracker
5 layers, double sided
strips
Collaboration founded in 1993
Detector commissioned in 1999
BABAR Status and Plans
37
DCH electronics upgrade
 Motivation:
o
Remove anticipated deadtime
problem due to serialization and
shipping of data from DCH to
readout module
 Upgrade in two steps:
o
o
Phase 1 (summer 2004): L1 to ~4kHz
• Reduce ADC payload (3216
bytes) from front ends with no
impact on dE/dx performance
Phase 2 (Oct 2005) : L1 to ~5kHz
• Larger FPGA to allow feature
extraction on DCH endplate
• New boards installed in Oct
down, ready to activate FPGA
code
Jan 25, 2006
BABAR Status and Plans
38
Jan 25, 2006
BABAR Status and Plans
39