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1# BaBar Outlook for next 3 years A.Jawahery University 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. Faccini’s talk next.
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2# BABAR Detector DIRC PID) 144 quartz bars 11000 PMs 1.5T solenoid EMC 6580 CsI(Tl) crystals Drift Chamber 40 layers Instrumented Flux Return Iron / Resistive Plate Chambers or Limited Streamer Tubes (muon / neutral hadrons) Silicon Vertex Tracker 5 layers, double sided strips e (3.1GeV) e (9GeV) Collaboration founded in 1993 Detector commissioned in 1999
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3# 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-Barcelona 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 A&M U Princeton U SLAC U of South Carolina 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 The BABAR Collaboration 11 Countries 80 Institutions 623 Physicists 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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4# BaBar Data
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5# The 1/ab Phase of BaBar 2006-2008 Integrated Luminosity [fb -1 ] 12 17 20 L peak = 9x10 33 Sep 05 plan Feb 06 (D. MacFarlane’s Guess)
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6# The BaBar detector : –Upcoming shutdown Aug through Dec. 06- complete the upgrade of the Instrumented Flux Return (IFR)- replace RPC’s with LST’s 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. Status of the experiment
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7# Status of the experiment Physics Analysis of BaBar Data: (See the details in R. Faccini’s 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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8# BaBar’s 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 physics reach far exceeds B physics: –Charm physics (D mixing, new Ds states…), Tau physics (LFV ,.......), ISR phys. –New states [found several- X, Y, Z’s (molecules?….)]…. Check: + + The Unitarity test: measure angles ( ) & sides of the triangle: Picture from A. Hoecker
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9# CP symmetry is broken in B decays: Sin2 measured in 2001 (BaBar & Belle)(BaBar & Belle) Direct CPV in B K BaBar & Belle) 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. m s is now tightly bound- the SM emerging as the winner again(Tevatron’s 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- & V td /V ts )<4%. How much of the program is done? Consistency of the CKM picture
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10# Any room for New Physics contributions? The analysis by the UTfit collab. allows NP amplitude and phase: [ Hep-ph/0509219] Non –SM solution is disfavored (0.4% probability) by Semileptonic asymmetry (A sl ) from BaBar & D0 SM solution C Bd =1 & Bd =0 New UTfit analysis with SL Asym & Bs mixing measurement At Tevatron hep-ph/0605213
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11# 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 sin2 penguin” test. EW radiative b s :: rates, direct CPV, photon helicity. EW radiative b s ll :: rates, direct CPV, AFB(q2), polarization effects,…. B s mixing: m s, s, (The Tevatron Territory for now)
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12# By 2002, measuring with B seemed hopeless- penguins too large to deal with & then came along the B system -longitudenally polarized system & small penguin contributions- to an accuracy of ~11 o The Dalitz (GGSZ) method for measuring expect eventual accuracy of few degrees The family of gluonic b s decays significantly expanded beyond B s -and CPV measured, increasing the sensitivity to NP searches New ways of exploiting the b s Now have access to photon helicity via B K s in addition to the rate and Direct CPV. Many new states observed; D sJ,, X, Y, Z states- rejuvenated the world of spectroscopy and their interpretation. We have also had a few pleasant unexpected results
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13# Physics Outlook for the 1/ab phase (~ +1/ab from Belle)
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14# David MacFarlane’s tables of BaBar’s 1/ab physics reach
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17# Inclusive Approach: Measure B X u l in a region of phase space where b cl pollution is small, e.g.: theoretical input to convert: u (meas) |V ub | - several approaches new & old BNLP: use b s & B->X c l to determine parameters of fermi motion of b in B m b, etc. the shape function. DGE : go from inclusive Semileptonic b decay to SL B meson decay- inputs: m b etc from b s & B->X c l Belle E.g. one of several lepton endpoint analyses with shape function |V ub |- One of the oldest and slowest advancing measurements The goal: |V ub |) ~5% BaBar
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18# Inclusive ~7% measurement now An overall eventual error of 5- 6% is not inconceivable. Ultimate limitation Charm may help Need confirmation From E. Barberio’s talk at FPCP06
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19# |V ub |-Exclusive approach: Identify b->u modes, such as B l,B l, B l,.. Measure partial decay rates, branching ratios & compare with theoretical expressions.. Lattice QCD provides normalization of F + (q 2 ) From Kevin Varvell’s talk at FPCP06
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20# 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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21# Measuring V ub = |V ub |e -i + B - (D f)K- F=common to D0 & anti D0 Decays involving interference of tree level b u & b c Processes. f=D CP (Gronau-London-Wyler)(GLW method) (small asymmetry) f=DCSD (Atwood-Duniets-Soni)(ADS Method) (additional problem of D ) f= Dalitz analysis of D0-> K s (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 )] Solve for & , – r B =(|A 1 |/ |A 2 |)
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22# From the Dalitz Analysis alone: =(67+/- 28 13 +/- 12 ) o (BaBar) φ3=53° +15 -18 3° 9°) Belle Combined (CKM fitter): = 65 +/- 20 o Measuring V ub = |V ub |e -i The method highly sensitive to r B : fits favor r B ~ 0.1 (BaBar) ; r B >0.2 (Belle). Main cause of the difference in errors Error due to uncertainties in treatment of the D K s -Dalitz plot (amplitudes and phases) -CLEO-c data can help. -Projected error from this source ~ 3-5 o (??)
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23# Requires improvement in D-Dalitz model – from CLEO-c data and higher statistics tagged D* events at B factories 2008: 5-10 o Future of Also needs additional help for r B E.g. Using the ADS observables : r B =0.1
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24# Time-dependent CPV measurement in neutral B’s E.g. for the Golden modes = u,c,tu,c,t u,c,tu,c,t WW WW J/ s sin 2
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25# Measuring sin2 Sin2 is a precision measurement now - the non-SM solution is essentially excluded B->J/ K* & B->D0h 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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26# easuring The prescription ….. But penguins (gluonic & E.W) can also lead to the same decays: With Tree alone Estimate by constructing the isospin triangle(Gronau & London) B-> sets the scale of the correction
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27# Good news for very lucky angle! Longitudinal polarization dominates- CP even & small B-> compared to B-> , B-> suppressed penguin contributions- Measuring A=-C
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28# Measuring o B only) B Already the error is systematic (theory) dominated. At ~2/ab, expect 7 o 10 o depending on the size of B-> Measuring B-> 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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29# B0B0 B0B0 f Within the SM: The “sin2 ” Test: Mixing induced CP violation in penguin modes b->sqq f cp S f ~ - cp sin2 Dominant amplitude (~ same phase as b->ccs suppressed amplitude (~ Expect within SM With new physics and new phases, S f could depart from - cp sin2 The Task: Measure S f =- cp S f – sin2 search for deviation from zero A Key Question: How well do we know S f within the SM? For f cp =from b->sqq
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30# SM expectation f Within the SM: Dominant amplitude (~ same phase as b->ccs suppressed amplitude (~ 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. S f depends on the size and the relative strong phase of this “suppressed “ term
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31# Simple average: S penguins =0.5 +/- 0.06 vs reference point: sin 69+/-0.03 ~ 2.5 deviation at this point. QCD factorization calculation of S Wait for R. Faccini’s talk for a more aggressive interpretation.
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32# Expectation for expt. accuracies of the “sin2 ” 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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33# 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: + E.g. B K : .. A contributing diagram from “New Physics” can alter A cp from the SM values. But need predictions of A cp within SM- Again rely on QCDF or PQCD, or exploit symmetries (SU2, SU3 etc) to connect A cp in different modes and derive sum rules- to be tested.
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34# A cp (B 0 K 0.108+/- 0.017 Within SM: Expect A cp b->s 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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35# A large body of data for Theories of Hadronic B decays to explain- accuracies to improve significantly- a few examples: Pattern of 2-body Br’s Pattern of Br’s & Polarization in B VV Many issues for TH to rule on: Tree/Penguin ratios; relative strong phases & direct CPV; Color suppression
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36# b s b sl + l - well established venues for NP searches Measured rates consistent with SM: BF(b → s ) TH = 3.57 ± 0.30 x 10 -4 (SM NLO) BF(b → s ) EXP = 3.54 ± 0.30 x 10 -4 (HFAG) bRbR tLtL bLbL W sLsL LL But there is more handles in these channels Photon polarization in b s L ( left-handed in SM) Direct CP violation – nearly zero in SM In B Kll- q 2 dependence of the rate; FB asymmetry, polariztion Search for NP modification of Wilson coefficients C7, C9, C10 (Riccardo Faccini’s talk for more details). D0
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37# Helicity Flip Suppressed by ~ m s /m b mixing Probing the helicity of the photon in b s via Time-dependent CP asymmetry measurements The value of S K* as a NP observable depends on SM uncertainties - recent work based on QCDF/SCET, considering the impact of b s (g) set S K* ~ 0.1 - (Grinstein, Grossman, Ligeti, Pirjol PRD 71, 011504(2005), Grinstein, Pirjol, hep-ph/0510104) (A. Atwood, M. Gronau & A. Soni (1997)) Within SM Needs much more data TDCP analysis requires modes common to B0 and B0(bar): e.g. B K*(890) with K* K 0 K 0 Ks with r ~ x10 -6
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38# 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, it’s still a great success- a “win win” situation. We’ll 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. Conclusion: & V td /V ts )<4% (mostly from Tevatron).
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39# IFR upgrade Impact Now: Barrel RPCs Now: Barrel LSTs
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40# Measuring sin2 B 0 tag _ sin2 = 0.652 ±0.039 (stat) ±0.020 (syst) A = 0.010 ±0.026 (stat) ±0.036 (syst ) Back
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41# Observation of direct CP violation in B 0 K + - HFAG Average BaBar 2004 New Belle Result: -0.113+/- 0.022+/- 0.008 232x10 6 BB’s A cp (B 0 K 0.108+/- 0.017 Back Includes CLEO & CDF
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42# From J. Charles @ FPCP 2006 Vancouver, Ca Check for New Physics contribution Back
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43# An MSSM analysis of b->s observables- ( L. Silvestrini- LP2005) -
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