Physics with BaBar 1999-2000 Data

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• BaBar
• Outlook for next 3 years
• JawaheryUniversity of Maryland
• June 6, 2006
• Outline
• A few comments on the status of the experiment.
• A brief overview of impact of BaBar physics
  outlook for the 1/ab phase.
• For a summary of the best and freshest results
  wait for R. Faccinis talk next.

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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)
Silicon Vertex Tracker 5 layers, double sided
strips
Instrumented Flux Return Iron / Resistive Plate
Chambers or Limited Streamer Tubes (muon /
neutral hadrons)
Collaboration founded in 1993 Detector
commissioned in 1999
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INFN, Perugia Univ INFN, Roma Univ "La
Sapienza" INFN, Torino Univ INFN, Trieste
Univ The Netherlands 1/4 NIKHEF,
Amsterdam Norway 1/3 U of Bergen Russia 1/13
Budker Institute, Novosibirsk Spain 2/3 IFAE-B
arcelona IFIC-Valencia United Kingdom
11/75 U of Birmingham U of Bristol Brunel U U
of Edinburgh U of Liverpool Imperial
College Queen Mary , U of London U of London,
Royal Holloway U of Manchester Rutherford
Appleton Laboratory U of Warwick
USA 38/311 California Institute of
Technology UC, Irvine UC, Los Angeles UC,
Riverside UC, San Diego UC, Santa Barbara UC,
Santa Cruz U of Cincinnati U of Colorado Colorado
State Harvard U U of Iowa Iowa State
U LBNL LLNL U of Louisville U of Maryland U of
Massachusetts, Amherst MIT U of Mississippi Mount
Holyoke College SUNY, Albany U of Notre Dame Ohio
State U U of Oregon U of Pennsylvania Prairie
View AM U Princeton U SLAC U of South Carolina
The BABAR Collaboration 11 Countries 80
Institutions 623 Physicists
Stanford U U of Tennessee U of Texas at Austin U
of Texas at Dallas Vanderbilt U of
Wisconsin Yale Canada 4/24 U of British
Columbia McGill U U de Montréal U of
Victoria China 1/5 Inst. of High Energy
Physics, Beijing France 5/53 LAPP, Annecy LAL
Orsay
LPNHE des Universités Paris VI et VII Ecole
Polytechnique, Laboratoire Leprince-Ringuet CEA,
DAPNIA, CE-Saclay Germany 5/24 Ruhr U Bochum U
Dortmund Technische U Dresden U Heidelberg U
Rostock Italy 12/99 INFN, Bari INFN,
Ferrara Lab. Nazionali di Frascati dell'
INFN INFN, Genova Univ INFN, Milano
Univ INFN, Napoli Univ INFN, Padova
Univ INFN, Pisa Univ Scuola Normale Superiore
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BaBar Data
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The 1/ab Phase of BaBar 2006-2008
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Sep 05 plan
Feb 06 (D. MacFarlanes Guess)
Integrated Luminosity fb-1
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12
Lpeak 9x1033
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Status of the experiment

• The BaBar detector
• Upcoming shutdown Aug through Dec. 06- complete
  the upgrade of the Instrumented Flux Return
  (IFR)- replace RPCs with LSTs in the remaining
  4 sectors (2 sectors were done in 2002).
• Recently completed an upgrade of the DCH
  electronics to reduce data flow.
• Some work needed on Level 1 trigger (NOT
  Hardware) to prepare for possible increases in
  the rate beyond the maximum 5 KHZ.
• May involve some tightening in trigger lines with
  possible impact on lower priority physics.
• No other major hardware work is planned on other
  sub-detectors.
• BaBar computing Data Management
• New computing model in place and functioning
  well. Able to keep up with data and simulation
  production.
• Caring for BaBar data - management, quality
  control, calibration...- is a huge part of the
  our activities and is expected to increase in
  importance, size and requirement for manpower in
  time.
• Will also require significant attention and
  support beyond 2008. The collaboration has just
  began discussing the requirements and strategy
  for BaBar beyond 2008.

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Status of the experiment

• Physics Analysis of BaBar Data (See the details
  in R. Faccinis talk)
• A well oiled analysis machine at work
• Over 200 different analysis projects are underway
• Have published/(submitted for publication) over
  200 papers so far.
• 150 abstracts submitted to ICHEP 2006 in Moscow

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BaBars initial Physics Goals Reach

• Examine breaking of the CP symmetry in B decays
• The CKM Test
• Does the CKM picture accommodate all CP
  conserving and CP violating observables in the
  flavor sector?
• Any room for New Physics effects?
• Search for New Physics in EW Gluonic
  penguin-domoniated B decays
• A major focus of this phase of BaBar

• The Unitarity test measure angles (a, b, g)
  sides of the triangle

Picture from A. Hoecker
Check a g bp ?
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How much of the program is done?

• CP symmetry is broken in B decays
• Sin2b measured in 2001 (BaBar Belle)
• Direct CPV in B?Kp 2004 (BaBar Belle)
• CKM established as the primary source of CPV in
  laboratory (as declared by Y. Nir- ICHEP2002).
• All three angles of the CKM unitarity triangle
  are now measured.
• Dms is now tightly bound- the SM emerging as the
  winner again(Tevatrons part).
• With the B factories in their 1/ab phase,
  Tevatron onward to 4-8/fb, Cleo-c more
  theoretical advancements, new goals are set for
  CKM observables-
• s(Vtd/Vts)lt4.

Consistency of the CKM picture
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Any room for New Physics contributions?

• The analysis by the UTfit collab. allows NP
  amplitude and phase Hep-ph/0509219

SM solution CBd1 fBd0
Non SM solution is disfavored (0.4 probability)
by Semileptonic asymmetry (Asl) from BaBar D0
New UTfit analysis with SL Asym Bs mixing
measurement At Tevatron hep-ph/0605213
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• The message from New Physics Fits to CKM
  observables (As presented at LP2005- by L.
  Silvestrini)
• New sources of CP violation in b?d s?d are
  strongly constrained.
• New Physics contributions to the b?s transitions
  are much less constrained are well motivated -
  further emphasizing the need to pursue NP
  searches in b?s transitions
• Gluonic penguins b?sg rates, direct CPV,
  the sin2b penguin test.
• EW radiative b?s g rates, direct CPV, photon
  helicity.
• EW radiative b?s ll rates, direct CPV,
  AFB(q2), polarization effects,.
• Bs mixing Dms, DGs, (The Tevatron Territory
  for now)

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We have also had a few pleasant unexpected
results

• By 2002, measuring a with B?pp seemed hopeless-
  penguins too large to deal with then came along
  the B?rr system -longitudenally polarized rr
  system small penguin contributions-
• ? a to an accuracy of 11o
• The Dalitz (GGSZ) method for measuring g expect
  eventual accuracy of few degrees
• The family of gluonic b?s decays significantly
  expanded beyond B?fKs -and CPV measured,
  increasing the sensitivity to NP searches
• New ways of exploiting the b?sg Now have access
  to photon helicity (via B?Ksp0 g), in addition
  to the rate and Direct CPV.
• Many new states observed DsJ, , X, Y, Z states-
  rejuvenated the world of spectroscopy and their
  interpretation.

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• Physics Outlook for the 1/ab phase
• ( 1/ab from Belle)

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David MacFarlanes tables of BaBars 1/ab physics
reach
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(No Transcript)
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(No Transcript)
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Vub- One of the oldest and slowest advancing
measurements
The goal s(Vub) 5

• Inclusive Approach Measure B?Xul n in a region
  of phase space where b?cl n pollution is small,
  e.g.

Belle
theoretical input to convert DGu(meas) ?Vub -
several approaches new old BNLP use b?sg
B-gtXcln to determine parameters of fermi motion
of b in B mb, l etc.? the shape function. DGE
go from inclusive Semileptonic b decay to SL B
meson decay- inputs mb etc from b?sg B-gtXcln
E.g. one of several lepton endpoint analyses with
shape function
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Inclusive
From E. Barberios talk at FPCP06
Ultimate limitation Charm may help
7 measurement now
An overall eventual error of 5- 6 is not
inconceivable.
Need confirmation
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• Vub-Exclusive approach
• Identify b-gtu modes, such as B?pln,B?rl n, B?wl
  n,..
• Measure partial decay rates, branching ratios
  compare with theoretical expressions..
• Lattice QCD provides normalization of F(q2)

From Kevin Varvells talk at FPCP06
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Experimental errors to shrink significantly,
which may allow discriminations amongst various
lattice calculations.
Other checks on lattice calculation from Charm
decays?
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Measuring g Vub Vube-ig
Decays involving interference of tree level b?u
b?c Processes.

B- ? (D?f)K- Fcommon to D0 anti D0
Solve for g, d(,d1-d2) rB(A1/ A2)
fDCP (Gronau-London-Wyler)(GLW method) (small
asymmetry) fDCSD (Atwood-Duniets-Soni)(ADS
Method) (additional problem of dD) f Dalitz
analysis of D0-gtKspp- (GGSZ) (combines
features of GLW ADS depending on the location
in Dalitz plot)- the dominant method Giri,
Grossman, Soffer, Zupan, PRD 68, 054018
(2003), Bondar (Belle), PRD 70, 072003 (2004)
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Measuring g Vub Vube-ig
The method highly sensitive to rB fits favor
rB 0.1 (BaBar) rB gt0.2 (Belle). Main cause
of the difference in errors
From the Dalitz Analysis alone g(67/- 28
? 13 /- 12 )o (BaBar) f353 15-18 ? 3
?9) Belle

• Error due to uncertainties in treatment of the
  D?Kspp-Dalitz plot (amplitudes and phases)
• CLEO-c data can help.
• Projected error from this source 3-5 o (??)

Combined (CKM fitter) g 65 /- 20o
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Future of g
2008 5-10o
rB0.1
Requires improvement in D-Dalitz model from
CLEO-c data and higher statistics tagged D
events at B factories
Also needs additional help for rB E.g. Using the
ADS observables
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Time-dependent CPV measurement in neutral Bs
?J/y K0s
E.g. for the Golden modes ?

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Measuring sin2b
Sin2b is a precision measurement now - the
non-SM solution is essentially excluded B-gtJ/yK
B-gtD0h No evidence for direct CP violation-
consistent with dominance of one diagram only-
At 2/ab (together with Belle) Expect another
factor of 2 reduction of errors
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Measuring a The prescription
B?p p (p p-, p p0, p0 p0 ) B?rp, B? r r, ..

With Tree alone
But penguins (gluonic E.W) can also lead to the
same decays
B-gtp0p0 sets the scale of the Da correction
Da
Estimate Da by constructing the isospin
triangle(Gronau London)
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Measuring a
A-C
A-C
Good news for a A very lucky angle! Longitudinal
polarization dominates-?CP even small B-gtr0r0
compared to B-gtrr0 , B-gtrr- ? suppressed
penguin contributions-
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Measuring a
a 96 /- 13o (B?rr only)
(B?rr, pp, rp)
Already the error is systematic (theory)
dominated. At 2/ab, expect s(a) 7o - 10o
depending on the size of B-gtr0r0 . Measuring
B-gtr0r0 its Time-dependent CP asymmetry may
shrink errors further- if able to to resolve
ambiguities.
Other ways of estimating penguin effects
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The sin2b Test Mixing induced CP violation
in penguin modes b-gtsqq
B0
fcp
B0
For fcp from b-gtsqq
Within the SM
f
Dominant amplitude (l2)- same phase as b-gtccs
suppressed amplitude (l4)
Expect within SM
Sf -hcpsin2b
With new physics and new phases, Sf could depart
from -hcpsin2b The Task Measure DSf-hcpSf
sin2b search for deviation from zero
A Key Question How well do we know DSf within
the SM?
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SM expectation
Within the SM
DSf depends on the size and the relative strong
phase of this suppressed term
f
Dominant amplitude (l2)- same phase as b-gtccs
suppressed amplitude (l4)
QCDF calculations(Beneke, hep-ph/0505075 Cheng,
Chua Soni, hep-ph/0506268).
SU(2) and SU(3) can also be put to work to
connect various CP conserving and CP violating
observables--generally much less restrictive- but
can improve with data.
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QCD factorization calculation of DS
Simple average Spenguins0.5 /- 0.06 vs
reference point sin2b0.69/-0.03 2.5 s
deviation at this point.
Wait for R. Faccinis talk for a more aggressive
interpretation.
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Expectation for expt. accuracies of the sin2b
test in 1/ab phase
And hoping (dreaming) for a pattern to
emerge! See G. Buchalla et al Hep-ph/050315 for
an analysis of several NP scenarios (albeit with
maximal effects)
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• Tests with Direct CP violations

Direct CP violation results when several
diagrams, with different cp conserving and cp
breaking phases contributing to the same final
state, interfere
B?Kp (K p- , K0 p , K0 p0 , ..)
E.g. B?Kp

A contributing diagram from New Physics can
alter Acp from the SM values. But need
predictions of Acp within SM- Again rely on QCDF
or PQCD, or exploit symmetries (SU2, SU3 etc) to
connect Acp in different modes and derive sum
rules- to be tested.
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Within SM Expect Acp(b-gtsg) 0
Acp(B0?Kp-) -0.108/- 0.017

• superweak is really out to use as NP observable
  need reliable QCD predictions Ample data to
  test calibrate the calculations on.

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A large body of data for Theories of Hadronic B
decays to explain- accuracies to improve
significantly- a few examples
Pattern of Brs Polarization in B?VV
Pattern of 2-body Brs

• Many issues for TH to rule on
• Tree/Penguin ratios relative strong phases
  direct CPV Color suppression

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b?sg- b?sll- - well established venues for NP
searches
Measured rates consistent with SM BF(b?sg)TH
3.57 0.30 x 10-4 (SM NLO) BF(b?sg)EXP 3.54
0.30 x 10-4 (HFAG)
D0

• But there is more handles in these channels
• Photon polarization in b?gsL (g left-handed in
  SM)
• Direct CP violation nearly zero in SM
• In B?Kll- q2 dependence of the rate FB
  asymmetry, polariztion
• Search for NP modification of Wilson
  coefficients C7, C9, C10
• (Riccardo Faccinis talk for more details).

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Probing the helicity of the photon in b?sg via
Time-dependent CP asymmetry measurements
(A. Atwood, M. Gronau A. Soni (1997))
Within SM
The value of SKg as a NP observable depends on
SM uncertainties - recent work based on
QCDF/SCET, considering the impact of b?sg(g) set
SKg 0.1 - (Grinstein, Grossman, Ligeti,
Pirjol PRD 71, 011504(2005), Grinstein, Pirjol,
hep-ph/0510104)
TDCP analysis requires modes common to B0 and
B0(bar) e.g. B?K(890)g with K?K0 p0 , K0
?Ks ?pp- with Br13.4x10-6
Needs much more data
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Conclusion

• BaBar is in excellent health able to operate,
  receive deliver the physics of 1/ab data.
• We are in the precision phase of this physics
  with achievable goals set for benchmark channels
  
• Given the large number of observables involved,
  a pattern is likely to emerge showing evidence
  for BSM physics. If we continue to see no
  deviation at these precisions, its still a great
  success- a win win situation. Well end up with
  a precisely constrained charged current sector of
  the Electroweak theory as a reference point for
  future searches for New Physics in the LHC era.

s(Vtd/Vts)lt4 (mostly from Tevatron).
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IFR upgrade Impact
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Measuring sin2b
B0 tag
sin2f1 0.652 0.039 (stat) 0.020 (syst) A
0.010 0.026 (stat) 0.036 (syst)
Back
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Observation of direct CP violation in B0?Kp-
232x106 BBs
New Belle Result -0.113/- 0.022/- 0.008
BaBar 2004
HFAG Average
Acp(B0?Kp-) -0.108/- 0.017
Includes CLEO CDF
Back
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From J. Charles _at_ FPCP 2006 Vancouver, Ca
Check for New Physics contribution
Back
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An MSSM analysis of b-gts observables- ( L.
Silvestrini- LP2005) -