S-Waves & the extraction of  s Sheldon Stone FPCP 2010, Torino, Italy, May 2010

Outline Mystery of Scalar Mesons Appearances of S-waves  D-> K pi nu  Ds-> K+K-pi+  Ds -> K+K- nu  B -> J/psi K* Measuring  s in VV decays  J/psi phi  phi phi & NP Possible effects of S-waves on  s (Franz example) A new possibility J/psi f0 decays  Predictions of branching ratios from Ds decays  Theoretical predictions (El-Bennich, Colangelo)  Estimation of possible sensitivity Conclusions (other places S-waves can appear -> K* mu mu) FPCP 2010, Torino, Italy 2

Mystery of Scalar Mesons 0 + nonet is not well understood Compare 0 - versus 0 +  For 0- nonet, the mass increases by ~400 MeV for each s quark. Why isn’t this true for the 0+ nonet?  Why aren’t the a o & the  degenerate in mass? Suggestions that the 0 + are 4-quark states FPCP 2010, Torino, Italy 3 Quarks Pseudoscalar Scalar ParticleMass (MeV) ParticleMass (MeV) 1/  2(uu+dd)  o 135  ~600 ud  a o us K  + ? ~900 ~ss  960 f o 980

S-waves in D s  K + K -  + decays Dalitz analyses (also E687) Fit using a linear S-wave + Breit-Wigner convoluted with Gaussian for the . Find 6.3% (8.9%) S-wave for  10 MeV (  15 MeV) FPCP 2010, Torino, Italy 4 CLEO ParticleJPJP Fit Fraction (%) (sums to 130%) K*(892)  1.5  (1020)  1.6 f o (980)  1.9 f o (1370)  0.6 K o *(1430)  0.5 f o (1710)  0.5 Bkgrnd subtracted

S-waves via Interference in semileptonic decays D +  K -  +  + : Though K  is dominantly K*, FOCUS observed an interfering S-wave amplitude with a rate fraction of (2.7±0.4)% for 0.8 < m(K  ) < 1.0 GeV D s  K + K - e + : S-wave fraction of for 1.01 < m(K + K - ) < 1.3 GeV (BaBar) FPCP 2010, Torino, Italy 5 weighted by cos  V

The S-Wave in B  J/  K* Two Vectors in final states so a transversity analysis is required BaBar & Belle measure interference between S & P waves in K* decay angle The fraction of S-wave intensity is (7.3  1.8)% for 0.8 < m(K  ) <1.0 GeV BaBar uses this interference to remove ambiguities in the measurement of cos(2  ) FPCP 2010, Torino, Italy 6 MC no interference B BaBar

Measuring  s in B s Decays FPCP 2010, Torino, Italy 7 Thus far B s  J/  used exclusively B s  suggested, for null measurement, as decay phase cancels mixing phase These modes are Vector- Vector final state, so must disentangle CP+ & CP- final states using an angular analysis V ts

Technique Without S-waves &  =0 A 0 P=+ longitudinal, A || P=+ trans, A  P= - trans For B s replace A  by -A . S-Wave term cannot be ignored (Stone & Zhang [arXiv: ])arXiv: Must add in S-wave amplitude and finite . FPCP 2010, Torino, Italy 8

All terms [Xie et al, arXiv: ] Time dependence (for ex.) Can write FPCP 2010, Torino, Italy 9

Estimate of S-wave Effect Adding A S can only increase the experimental error. The size of the effect depends on many factors including the magnitude & phase of the S- wave amplitude,  s, values of the strong phases, detector acceptances, biases.. One simulation for LHCb by Xie et al  Assumes either 5% or 10% S-wave with phases either 0 or 90 o.  Simulates many Pseudo experiments  Bias of -10%, error increases by 15%. Can also use to eliminate  s ambiguity FPCP 2010, Torino, Italy 10 Ignore A S Include A S -2  s

Estimates of J/  f 0 (980) Can use S-wave materializing as f o (980) for CP measurements (Stone & Zhang [arXiv: ])arXiv: The final state J/  f o is a CP+ eigenstate No angular analysis is necessary! This is just like measuring J/  K s. The modes J/  J/   can also be used, but they involved  ’s in the decay & thus have lower efficiency at hadron colliders Define: FPCP 2010, Torino, Italy 11

Estimate Using Hadronic D s Decays M(B s )-M(J/  )= = 2270 MeV M(D s )-M(  ) = 1830 MeV, not too different Use CLEO result for D s  K + K -  + extrapolated to zero  width to extract B (D s  +,  K + K - ) = (1.6±0.1)% FPCP 2010, Torino, Italy 12

Estimate from D s  h + h -  + CLEO: B (D s  +  +  - ) = (1.11±0.07±0.04)% Use BaBar Dalitz analysis to estimate fraction of f o  + [arXiv: ] Estimate (27±2)% of final state is in narrow f o peak There is more S-wave under f o peak FPCP 2010, Torino, Italy 13 bkgrnd fofo

Estimate from D s  (  /f o ) e + Compare semileptonic rates near q 2 =0 to get maximum phase space CLEO [arXiv: ] FPCP 2010, Torino, Italy 14 f o e +  e +

Semileptonic estimate At q 2 =0, where phase space is closest to B s  J/  (  /f o ) Note that at q 2 =0 and in the case of D s , the  is forced into a longitudinal polarization state CDF measures only 53%  L, so these rates may be too large by x2 FPCP 2010, Torino, Italy 15

Theory Estimates of R f o /  Colangelo, De Fazio & Wang [arXiv: ] Use Light Cone Sum Rules at leading order in  s. Prediction 1: B(  ) measured = (1.3±2.4)x10 -3  B(f o )=(3.1±2.4)x10 -4 (0 th order), R=24%  B(f o )=(5.3±3.9)x10 -4 (leading order), R=41% Prediction 2: Using ff for  from Ball & Zwicky [arXiv:hep-ph/ ] R LarXiv:hep-ph/ =0.13±0.06 (0 th order), 0.22± st order FPCP 2010, Torino, Italy 16

Check on Prediction Note that Colangelo et al predict BR(Ds  f o e + ) = ( −0.4 ) × 10 −3, While CLEO measures BR(Ds  f o e + ) = (4.0 ± 0.6 ± 0.6) × 10 −3, Which implies that the calculated form-factor is low by a factor of 2, thus compensating for  L /  total = 0.53 FPCP 2010, Torino, Italy 17

QCD Factorization O. Leitner etal [arXiv: ]  Assume f Bs = 260 MeV, f fo = 380 MeV Predict B (B s  J/  f o ) = 1.70 x B (B s  J/   ) = 9.30 x R fo/  = They show small variation with B s  f o form factor; “annihilation” effects important and decrease f o rate. “S-wave kaons or pions under the  peak in J/  are very likely to originate from the similar decay J/  f o. Therefore, the extraction of the mixing phase from J/  may well be biased by this S-wave effect which should be taken into account in experimental analysis” FPCP 2010, Torino, Italy 18

Summary of R estimates Measurement will constrain theories FPCP 2010, Torino, Italy 19

 s Sensitivity Using J/  f o From Stone & Zhang [arXiv: ] for LHCb Assume R f o /  = 25% Assume 2 fb -1 at 14 TeV (~4 fb -1 at 7 TeV) Error in -2  s  J/   0.03 rad (not including S-wave)  J/  f o, f o       0.05 rad  J/  f o + J/  ′,  ′       rad The f o mode should be useful FPCP 2010, Torino, Italy 20

B s  J/  f o Signal Selection FPCP 2010, Torino, Italy 21

Conclusions S-waves are ubiquitous, they appear whenever looked for, & must be taken into account in B s  J/   measurements of amplitudes, phases, & CP violation Suggestions: add S-wave amplitudes in the analysis of B  K*     & surely in B s  B s  J/  f o may be a useful mode to add to the statistical precision on the measurement of -2  s, & hopefully will provide useful checks since angular measurements are not necessary FPCP 2010, Torino, Italy 22