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Spectroscopy potentialities of SuperB

Spectroscopy potentialities of SuperB. Conveners: Riccardo Faccini , Antonello Polosa University “La Sapienza” and INFN Rome Other Contributors: Robert McElrath CERN Miguel Angel Sanchis Lozano IFIC, Valencia SuperB Workshop Isola D’Elba, May 31 st 2008.

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Spectroscopy potentialities of SuperB

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  1. Spectroscopy potentialities of SuperB Conveners: Riccardo Faccini, Antonello Polosa University “La Sapienza” and INFN Rome Other Contributors: Robert McElrath CERN Miguel Angel Sanchis Lozano IFIC, Valencia SuperB Workshop Isola D’Elba, May 31st 2008

  2. Only charmonium and bottomonium considered here Quarkonium for Pedestrians • Quarkonium is a bound state of a quark and an antiquark • Relevant quantum numbers: n,L,S,J • Relationship with Parity and Charge Conj: • P=(-1)L+1, C=(-1)L+S • Not all JPC allowed (e.g. 0+-,0--,1-+,2+- forbidden) • Decay Properties: • Below open quark threshold (e.g. (cc)DD) only electromagnetic or as suppressed decays allowed  mostly narrow states • Above open quark threshold (if DD decays allowed) mostly broad states • What can we learn? • Understanding of QCD: • ‘regular quarkonium’  tests of NRQCD, potential models, … • ‘new states’  new forms of aggregations mediated by the strong interactions

  3. Beyond the quarkonium • Search for states with 2 quarks+”something else” • New forms of aggregation • Expected but never identified!!! • Hybrids: qq+n gluons • Lowest state 1-+ (forbidden for quarkonium) • Dominant decay HDD** • Tetraquarks: [qq’][qq’] • Large amount of states • small widths also above threshold • Molecules: M[qq]M[q’q’] • Smaller number of states but still small widths also above threshold • Search for resonances: • with non-quarkonium JPC • unnaturally small widths • not null charge: would be clear indication of something new going on

  4. Light mesons

  5. The topic • Possibility that the scalar nonet is a tetraquark • Observation: inverted spectrum of 0+ wrt 0-: in the case of the scalars the mass decreases with increasing strange content • Good explanation: bound [qq’][q’’q’’’] states

  6. II step • Verify the nature of these scalars • Dispersion relations relate time-like and space-like form factors • Search for the higher multiplets Glueball?

  7. High q2 scaling law and # hadronic fields • Pacetti et al. have published evidence from e+e- fX Xsecions as a function of q2, measured in BaBar ISR data, that • X=h behaves like a meso, X=f0 as a tetraquark • With more statistics (and J/y decays): • Higher mass f0? • Glueball? Helicity cons? # hadronic fields 3 had fields no cons 2 had fields no cons 2 had fields +cons

  8. Other tetraquark candidates (?) BaBar – 232 fb-1 • Y(2175) observed decays: • ff0 – discovery mode • Good match to [ss][ss] tetraquark RF, A.Polosa, N. Drenska work in progress • Also hints in fh, KsKp, … ?

  9. SuperB perspective • More statistics is needed for : • Search for lower BF modes • Search for additional states • Investigation of threshold effects (e.g. e+e- LcLc)

  10. Charmonium and the new zoology

  11. Charmonium: state of the art same JPC as J/y but mostly D wave ! (2S+1)LJ y(4160) Increasing L  M(MeV) y(4040) Open charm thr. y(3770) Increasing n  h’c y’ cc2 hc cc1 cc0 Recent acquisitions J/y hc (pot. Models) QWG: hep-ph/0412158 JPC Basically all states below the open charm threshold are observed and explained

  12. X(3872): known facts • Decays • XJ/y pp (original observation) • Maybe J/y r • BF(XJ/y w)~ BF(XJ/y r) • XJ/y g Implications: • C(X)=+1 • C(pp in J/y pp decay)=-1 • I(pp)=L(pp)=1  consistent with J/yr decay hyp. • Production • only B decays so far • No prompt e+e- production observed (BaBar arXiv:0707.1633) Belle+BaBar

  13. Analysis of JPC of X(3872) PRL 98:132002 (2007) Full angular analysis of XJ/ypp decays Only compatible options: JPC=1++ or 2-+ (and with J(pp)=1) 1++ 2-+ Belle (hep-ex/0505038) disfavours P=-  JPC=1++ 1-- 0++

  14. The X(3872) puzzle Not matching any predicted state! Above DD threshold (allowed): should have large width but it is narrow Charmonium highly suppressed decay into J/y r (isospin violation) y(4160) (2S+1)LJ Increasing L  M(MeV) Open options • DD* molecule • Right above the threshold • favours DD* decay over J/ypp over J/yg (as observed) • Tetraquark • Explains small width • Predicts a set of 4 states (2 charged and 2 neutral). • Finding the charged state is critical y(4040) X(3872)? Open charm thr. y(3770) Increasing n  h’c y’ cc2 hc cc1 cc0 J/y (pot. Models) hc JPC

  15. X(3872) mass [my extrapolation] Poor agreement among mass measurements: XJ/ypp and XDD(*) differ by ~4.5s Neutral and charged B mesons in XJ/ypp by 1.5s DD average J/ypp average Predicted by tetraquark model (but why so close to threshold?) TWO STATES? X(3872) & X(3876) ?

  16. The 1-- family Several resonances observed in e+e- YgISR(certainly JPC=1--) Y(4260)J/ypp Confirmation + J/yp0p0: CLEO PRD74, 091104 (2006) CLEO-c PRL 96, 162003 (2006) A new state: Y(4260) PRL 95, 142001 (2005) Yet another state Y(4350) PRL 98, 212001 (2007) Y(4350)y(2S)pp

  17. The youngest of the 1-- family arXiv:0707.3699 arXiv:0707.2541 Confirmation of BaBar 5.8s NEW NEW NEW Zoomed BaBar YJ/ypp Yy(2S)pp

  18. Y(4008) Y(4260) High mass region Decay properties DECAY PROPERTIES NEW f0 dominating? Threshold effects? Y(4660) Y(4350)

  19. [Belle: arXiv:07080082] hep-ex/0607083 D(*)D(*) in ISR DD Most of these 1-- states should preferentially decay into D(*)D(*) states. Can we see them? y(3770), y(4040), y(4415) [regular charmonia] clearly visible, nothing else PRL 98, 092001 (2007) D*D*  Basically all R scan other than non-resonant continuum understood DD* Xsection (pb) DDπ,not D(2010,2007) arXiv:07080082 S [D(*)D(*)(p)] continuum

  20. 1-- family: recap Only seen in y(2S)pp (2S+1)LJ • Not matching any potential model prediction • Too narrow 4660 M(MeV) 4350 y(4160) 4260 4008 y(4040) 4 Ys to place ! Open charm thr. y(3770) y’ “new physics”? 4260 can be fit by a tetraquark model (decaying into J/yf0 …) or a hybrid (with gpp) J/y Why not the ordinary Y(4040)? (pot. Models) JPC 1-- 1--

  21. The first charged state: Z(4430)! B±Z±Ks or B0ZK± Z±y(2S)p± BELLE-CONF-0773 • Total significance: 7.3s • M = (4433±4) MeV • = (44+17-13) MeV BF(BKZ)xBF(Zy(2S)p)=(4.1±1.0±1.3) 10-5 Too narrow to be a reflection Xcheck: separate in subsamples BF and mass consistent between B± and B0 within large errors [in B± decays M=(4430±9) MeV ; BF±/BF0=1.0±0.4 ] Prior search with no evidence: BX+K with X+J/y pp0 PRD 71, 031501 (2005)

  22. Summary Updated properties The 1-- family: Charmonia, tetraquarks, molecules, hybrids?!? (2S+1)LJ Z(4430): the first charged state M(MeV) y(4415) y(4160) X,Y News on the 3940 family X(3872) the best tetraquark candidate y(4040) X Z Open charm thr. y(3770) h’c y’ cc2 hc cc1 cc0 Yet another particle: X(4160) [hc(3S)?] J/y (pot. Models) hc JPC + updates on Y(nS)Y(mS) transitions

  23. The observation matrix

  24. Predicted spectrum/production Predicted by tetraquark model – each represents a nonet of states !!!

  25. SuperB perspective • High statistics: • Look for lower production and BF modes • In particular D(s)(*)D(s)(*) modes • Complete the picture • Scan the c.o.m. energy • “sit” on a resonance, if JCP=1— • Pair production for other JCP. • “sit” on Y(4S) or Y(5S) for Bd or Bs decays

  26. Bottomonium and exotica

  27. Bottomonium: state of the art hb (x3) completely missing 2 hb and 3 D wave states are narrow but not observed Open bottom thr. Increasing L  Y(3S) c(2P)b{2,1,0} Y(1D) Y(2S) Increasing n  c(1P)b{2,1,0} Unconfirmed J assignments of all the cb s Y(1S) (pot. Models) QWG: hep-ph/0412158 8 narrow resonances still missing ! Searches optimal running @(3S) or (2S)

  28. Exotic states expectations • Several unexpected 1– charmonium-like states [Y(4260),Y(4350),Y(4660)] have been observed decaying into J/y or y(2S) and two pions • Exotic particles, candidates for tetraquarks and hybrids / new spectroscopy in general • Sitting at their center of mass would allow a much better understanding of their decay properties • Going so much down in energy is not feasible for PEP • We can look for the bottomonium-like partners • Distances between states are not dramatically affected by exchanging b and c  can roughly predict bottomonium states by adding ~6350 MeV to charmonium states (2S+1)LJ Open bottom thr. Increasing L  Increasing L  y(4160) 360 MeV 330 MeV Y(3S) y(4040) c(2P)b{2,1,0} Increasing n  Increasing n  Y(1D) Open charm thr. y(3770) Y(2S) y’ h’c 590 MeV cc2 hc 560 MeV c(1P)b{2,1,0} cc1 cc0 J/y Y(1S) hc JPC Bottomonium Charmonium

  29. Properties of possible exotic states b,u u,b • JPC=1-- : could be produced in e+e- collisions • Masses (obtained scaling from Charmonium to Bottomonium) Y(4260)  Yb(10610) Y(4350)  Yb(10700) Y(4660)  Yb(11010) • Width (dominated by this diagram in tetraquark/molecules) Independent from the heavy quark: G(Yb)~G(Y)=50-150MeV • Decay channels • Easiest to detect: YbX (X=pp,p0p0,ppp0,KK,p0,h) • Because of the same graph estimate BF(Ybpp)~ BF(Yypp) (if mediated by single meson) • Production cross-section • Smaller than Y because of charge (s(e+e-Yb)~s(e+e- Y)/4) • Smaller than regular bottomonium because need to produce more than just two quarks  Expect s(e+e-Yb)BF(Ybpp)~ s(e+e-Y)BF(Yypp)/4 ~25pb (or less if Ybpp not mediated by a single meson) u b b u b u Most likely

  30. Tetraquark candidates: Y(5S) Recent observation from Belle of unusual behaviour of Y(5S) in its decay to Y(nS)pp  Y(5S) good tetraquark candidate  Expect to see other resonances with such an eccess Belle: L=21fb-1 @ Y(5S) Regions of interest (+ above (5S) not in this plot) • This measurement also tells us that s*BF(Yb(1S)pp) ≤10 pb • Belle has performed a 6fb-1 scan between 10.86-11.02 GeV

  31. SuperB role • Possible low production Xsections • Low BF in detectable decays • Need to perform an extremely high luminosity scan of the region to search for them

  32. M.A. Sanchis Lozano Higgs in  decays -   A0 • Existence of light Higgs (mH<2mb) not completely ruled out @LEP • Some models (e.g. NMSSM) actually predict one • YA g with Att • Two possible experimental approaches: • Measure R=BF(ttng)/BF(llng) • Best when mA~m • Tag explicitely the monochromatic photon and the t-pair • Might be systematics limited very early + b intermediate state or bb continuum Do B-Factories already saturate the discovery potential? 5s discovery potential in 1ab-1

  33. R. McElrath Dark Matter/SUSY • Light Dark matter might also have eluded LEP searches if mildly coupled with the Z • invisible • Several modes beyond the SM predict Y to decay to particles which are not observed (typically neutral LSPs) • Search for single photon or for (3S)(1S)p+p-nothing p+p- Still missing and exp view on this  expertise being built in BaBar

  34. The physics case in few words • There are indications that strong interactions do not only form mesons and baryons, but also other forms of aggregation • A major step forward in the understanding of nature • Converting these indications into a solid set of measurements is within the reach of SuperB • SuperB is ideal because of: • High luminosity • Adjustable energy (importance of scan) • Twofold task: • Discriminate among possible interpretations (regular mesons, molecules, tetraquarks, hybrids,…) • Complete the picture • Very large number of missing states • There are new physics models that predict Higgs bosons at masses below 2mb to have escaped LEP searches. • We will explore which are the search channels that require SuperB statistics

  35. bakup

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