1 / 19

hadrons

. The Impact of BaBar ISR data on the SM Muon Anomaly Prediction. Michel Davier Laboratoire de l’Accélérateur Linéaire, Orsay. Muon Magnetic Moment Workshop October 25 - 26 , 200 7 , University of Glasgow. . . . hadrons. davier@lal.in2p3.fr. Goals of the BaBar ISR Program.

tanner-sweet
Download Presentation

hadrons

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Impact of BaBar ISR data on the SM Muon Anomaly Prediction Michel Davier Laboratoire de l’Accélérateur Linéaire, Orsay Muon Magnetic Moment Workshop October 25 - 26, 2007, University of Glasgow    hadrons davier@lal.in2p3.fr

  2. Goals of the BaBar ISR Program Precise measurements of cross section for all significant processes, e+e hadrons, from threshold to ~4-5GeV • Measure , KK channels with high precision • Summing up exclusive cross sections==>Improve the precision of R • Study spectroscopy of JPC=1−− states and their decays M. Davier et al., 2003 Ös

  3. Exclusive Channels with BaBar ISR ISR • systematic program underway using ISR from (4S) energies, taking • advantage of high luminosity (B-factory) • statistics comparable to CMD-2/SND for Ecm<1.4 GeV, much better than • DM1/DM2 above • full energy range covered at the same time • channels identified using particle ID and kinematic fitting • systematic uncertainties at 5-10% level • large acceptance for hadronic system (boosted opposite to ISR photon) X = 2E /Ecm H is radiation function

  4. BaBar ISR: e+ehadrons • Reactions for which results have been published : • ppPRD 73, 012005 (2006) • p+p-p0 PRD 70, 072004 (2004) • 2p+2p-, K+K-p+p-, PRD 71, 052001 (2005) • K+K-p+p- K+K-p0p0 , 2K+2K- PRD 76, 012008 (2007) • 3p+3p-, 2p+2p-p0p0, K+K-2p+2p- PRD 73, 052003 (2006) • New results presented last Summer : • K+Kp0,KSKp+,K+Kh, subm. to PRD arXiv:0710.xxxx [hep-ex] • LL , LS0 , S0S0subm. to PRD arXiv:0709.1988 [hep-ex] • +ppBaBar Preliminary • 2p+2pp0,2p+2ph,KK p+pp0, KKp+ph accept. by PRDarXiv:0708.2461 [hep-ex] • Work in progress: • ,K+K, p+p3p0 • Inclusive R

  5. BaBar ISR:  errors include systematics huge discrepancy with DM2 SND BaBar DM2 contribution to ahad (1.05-1.8 GeV) : • all before BaBar 2.45  0.26  0.03 • all + BaBar 2.79  0.19  0.01 • all – DM2 + BaBar 3.25  0.09  0.01 x1010

  6. BaBar ISR: 22 contribution to ahad (<1.8 GeV) : • all before BaBar 14.20  0.87  0.24 • all + BaBar 13.09  0.44  0.00 x1010

  7. BaBar ISR: 33 BaBar contribution to ahad (<1.8 GeV) : • all before BaBar 0.10  0.10 • all + BaBar 0.108  0.016 x1010

  8. BaBar ISR: 222 BaBar contribution to ahad (<1.8 GeV) : • all before BaBar 1.42  0.30  0.03 • all + BaBar 0.890  0.093 x1010

  9. BaBar ISR: +00 Only statistical errors plotted BaBar preliminary ψ ->p0p0J/ψ(->mm) J/ψ • Previous situation chaotic • Preliminary syst. error: 8% in peak 5% • Good agreement with SND <1.4 GeV • Huge improvement >1.4 GeV • First measurement >2.5 GeV

  10. BaBar ISR: +00--substructure • Intermediate states: • 0 • +- large and first seen • 0 f0(980) • a1(1260) BaBar preliminary MC

  11. BaBar ISR: ++0 Cross sections of sub-mode: +-  0  X =  3 + 0 3 : from subtraction /+-  0 3

  12. BaBar ISR:+p- BaBar preliminary BaBar,3   BaBar preliminary f0(980) 1st measurement 1.35  0.03 0.45  0.14 1.66  0.01 0.22  0.04 BaBar,3

  13. BaBar ISR: p+-+p- • ~4,300 events selected • first measurement BaBar preliminary

  14. BaBar ISR:KSK, K+K-p KSK-++- Dominant states: K*(980)K and K2*(1430)K K+K-p Isoscalar channel dominates over isovector Parameters(1680): PDG m=172320 MeV, 168020  = 37175 MeV, 15050 ee= 58060 eV, B/BK*K 1/3

  15. BaBar ISR: KK, K+K-pp K+K-p+p- Substructure in the final state K*(892) - 1 per event K+K-0p0 K+K-0 p0 K1(1270),K1(1400) – 1+ K+K-p+p- ~ 1500

  16. BaBar ISR:KKKK,KKppp,KKpp K+K- K+K- jK+K-dominated J/Y K+K-+p-p K+K-+p- First measurement !

  17. BaBar ISR: KKpppp Cross section Substructures K*0(892) j J/y first measurement

  18. Present BaBar Measurements only statistical errors syst. 5-10% to obtain R in the energy range 1-2 GeV the processes +-, +-30, +-40, K+K-, KSKL, KSKL, KSK+-0 remain to be measured

  19. Conclusions • program underway with BaBar to measure all significant exclusive cross sections for ee  hadrons using ISR • many channels already published; more underway • should allow reconstruction of R from threshold to 2 GeV • will match inclusive data from BES from 2 to 5 GeV • important input for VP calculations and QCD analyses • BaBar will be the only experiment able to provide the whole input in the low-energy region, with good accuracy

More Related