Physics Case of L=10 36 e + e - B Factory

1. Physics Case of L=1036 e+ e- B Factory Achille Stocchi LAL-Orsay Université Paris-Sud and IN2P3-CNRS

2. Two of such projects exist 1. « SuperBelle in Japan » 2. « SuperB in Italy » (See Christoph Schwanda talk) Today it seems that SuperBelle project converges to the « italian » solution for the machine (« crab waist ») Good new !  SuperB from now on Today I defend the physics case for a machine which I call SuperB :  very high luminosity L> 1036cm-2 sec-1 With two possible options :  possibility of running at different energy thresholds (B t-charm..)  possibility of having polarized beams. L= 1036cm-2 sec-1 ∫L= 15ab-1 per year Today ∫L= 1ab-1  ∫L= 100ab-1

3. Few questions I’ll try to answer in this talk Is a SuperB a discovery machine in LHC era ? Why >1036 luminosity needed ? Is SuperB complementary to LHC ? Would not be LHCb enough to perform flavour studies ? Its is any interest of running at the t–charm threshold ? Is it important to have al least one beam polarized ? (See Christoph Schwanda talk) How to built such a Factory ?

4. “Quantum path” “Relativistic path” Crucial : Center-of-mass energy Crucial : Luminosity SuperB The quantum stabilization of the Electroweak Scale suggest that NP is @ ~ 1 TeV LHC will search on this range - if NP particles are discovered at LHC we are able to study the flavour structure of the NP - we can explore NP scale beyond the LHC reach 1034 EW scale ~100GeV 1036 TeV scale

5. B physics @ Y(4S) Possible also at LHCb Similar precision at LHCb Example of « SuperB specifics » inclusive in addition to exclusive analyses channels with p0, g’s, n, many Ks…

6. Charm at Y(4S) and threshold t physics (polarized beams) To be evaluated at LHCb Bs at Y(5S) Bs : Definitively better at LHCb

7. Determination of CKM parameters and New Physics Today SuperB+Lattice improvements Improving CKM is crucial to look for NP r = 0.163 ± 0.028 h = 0.344± 0.016 r = ± 0.0028 h = ± 0.0024

8. Let’s consider (reductively) the GOLDEN MATRIX for B physics X X X- CKM X X X X- CKM X The GOLDEN channel for the given scenario Not the GOLDEN channel for the given scenario, but can show experimentally measurable deviations from SM. X « SuperB specifics » inclusive analyses channels with p0, g, n, many Ks… In the following some examples of

9. 10 ab-1 75 ab-1 2 ab-1 M(H+)(TeV) tan b Leptonic decay B  l n Today some >2s discrepancy.. SuperB -75ab-1 MH~1.2-2.5 TeV for tanb~30-60 Exclusion regions @ 2s in case of no-signal

10. New Physcs in bs transitions B  K*l+l-: AFB 50ab-1 Y.-G. Xu et al., PRD74, 114019 (2006) 1 10-1 10-2 • Flavour-changing NP effects in the squark propagator • NP scale SUSY mass • flavour-violating coupling In the red regions the d are measured with a significance >3s away from zero = (0.026 ± 0.005) Arg(d23)LR=(44.5± 2.6)o New Physics contribution (2-3 families) ~ g ~ ~ s b s b 1 10 1 TeV

11. New Physcs in bd transitions 10ab-1 75ab-1 Determination of SUSY mass insertion parameter (d13)LL with 10 ab-1 and 75 ab-1 Importance of having very large sample >75ab-1

12. Br(B  K n n) – Z penguins and Right-Handed currents today h SM Only theo. errors e If these quantities are measured @ <~10% deviations from the SM can be observed ~[20-40] ab-1 are needed for observation>>50ab-1 for precise measurement

13. Lepton Flavour Violation in t decays MEG sensitivity meg ~10-13 Preliminary results < 3 10-11 Masurements and origin of LFV Discrimination between SUSY and LHT SO(10) MSSM 107 BR (tmg) LFV from PMNS SuperB LFV from CKM The ratio t lll / t mg is not suppressed in LHT by ae as in MSSM M1/2

14. Polarized beams Polarized beam is (SuperB specific) t anomalous moment (g-2) LFV analyses : novel additional handle on backgrounds The anomalous tau momentum influence both the angular distribution and the t polarization. Measure the Re(F2) and Im(F2) of the (g-2) from factor NP effects ~ 10-6 < Polarisation is -an important issue for LFV -opens the possibility of measuring (g-2) -…. Under study

15. Charm Physics Running at charm threshold (SuperB specific) Charm physics using the charm produced at U(4S) Consider that running 2 month at threshold we will collect 500 times the stat. of CLEO-C Charm physics at threshold 0.3 ab-1 Strong dynamics and CKM measurements @threshold(4GeV) x~1%, exclusive Vub ~ few % syst. error on g from Dalitz Model <1o D decay form factor and decay constant @ 1% Dalitz structure useful for g measurement D mixing Rare decays FCNC down to 10-8 Better studied using the high statistics collected at U(4S) @threshold(4GeV) CP Violation in mixing could now addressed

16. CP Violation in charm NOW CPV in D system negligible in SM SuperB CPV in D sector is a clear indication of New Physics !

17. L= 1036cm-2 sec-1  15ab-1 per year We need at least 75 ab-1  L= 1036cm-2 sec-1 is the baseline option That’s is the factory we need ! Unprecented precision SuperB can perform many measurements at <1% level of precision Precision on CKM parameters will be improved by more than a factor 10 … and do not forget… SuperB could also a Super-Supert-charm factory, If we run at threshold. Unique opportunity of LFV measurements, better if beam polarized. SuperB Discovery Potential and Complementary to LHC NP will be studied (measuring the couplings) if discovered at LHC if NP is not (or “partially”) seen at TeV, SuperB is the way of exploring NP scales of several TeV (in some scenario several (>10 )TeV..)

18. Backup Material

19. The problem of particle physics today is : where is the NP scale L ~ 0.5, 1…1016 TeV The quantum stabilization of the Electroweak Scale suggest that L ~ 1 TeV LHC will search on this range “Quantum path” What happens if the NP scale is at 2-3..10 TeV …naturalness is not at loss yet… Flavour Physics explore also this range We want to perform flavour measurements such that : - if NP particles are discovered at LHC we able study the flavour structure of the NP - we can explore NP scale beyond the LHC reach 1034 luminosity to have measurable effects (anyhow) if NP particle with masses at the EW scale 1036luminosity to have measurable effects (anyhow) if NP particle with masses at the TeV scale

20. Special specific meeting to answer the IRC questions on physics and sharpen the physics case 49 signers ~24 institutions SuperFlavourFactory 3 Chapters : Physics Case Detector Machine > 1036cm-2 sec-1  >15ab-1 per year (today ~1034cm-2 sec-1Babar~400fb-1 Belle~700fb-1 ) Background machine ~ to the present one 320 signers ~80 institutions 444 pages Possibility of running at lower (t-charm) and higher energy (Bs)

24. Another example of sensitivity to NP : sin2b from “s Penguins”… W- s b f t s B0d s K0 d d ~ g  5 discovery possible (extrapolating from today) ~ ~ s b s b Many channels can be measured with DS~(0.01-0.04) bs penguin processes bd SuperB (*) theoretical limited

25. more.. tan b tan b tan b tan b B  t n and B  m ncombination exclusion plots in [ M(H+), tan b]

26. BR e beam polarization  Lower Background SuperB Sensitivity (75ab-1) LHC(b) • LHC is not competitive (Re: both GPDs and LHCb). • SuperB sensitivity ~10 – 50 better than NP allowed branching fractions. SuperB

27. MFV : Snowmass points on t SuperB with 75 ab-1, evaluation assuming the most conservative scenario about syst. errors LFV 5s disc 1÷2 LFV from CKM Letpon MFV GUT models LFV from PMNS

28. <1 Make use of all the informations (total x-section,angular distribution, f-b asymmetry. Measure Re and Im parts Tau g-2 Start with the expt. with m

29. Spectroscopy

32. MFV : SNOWMASS points SPS4 ruled out by present values ofBsg. SPS1a is the least favorable for flavour, but SuperB and only SuperB can observe 2sdeviations in several observables