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Open Charm Spectroscopy. Charm Production at B-Factories D-Meson Spectrum D s -Meson Spectrum Spectroscopy in D (S) decays Outlook. Klaus Peters GSI/GU Frankfurt Nov 19, 2009 Mainz. Motivation. Until 2003: D/D s spectra was not very exciting. (Godfrey,Isgur). Prediction
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Open Charm Spectroscopy Charm Production at B-Factories D-Meson Spectrum Ds-Meson Spectrum Spectroscopy in D(S) decays Outlook Klaus Peters GSI/GU Frankfurt Nov 19, 2009 Mainz
Motivation • Until 2003: D/Dsspectra was not veryexciting (Godfrey,Isgur) Prediction Godfrey,Isgur/ DiPierro, Eichten Measurement D Klaus Peters – Open Charm Spectroscopy
Motivation • After 2003: Further states, partly very narrow (Ds system) • inconsistent with theoretical expectations Ds0*(2317), Ds1(2460) (Godfrey,Isgur) (nat. JP) Prediction Godfrey,Isgur/ DiPierro, Eichten Measurement D Evidencefor 2 newstates 4 newstates Klaus Peters – Open Charm Spectroscopy
Motivation • Nature oftherecentlyfoundstates? - cu/cd, csstates (+c.c.) • - tetraquarkstates (e.g. csdd) • - molecularstates (nearthreshold, e.g. cd-ds) • Experimental observables - masses • - lifetime/width/partial decaywidths - spin-parity - isospin (via decay) - mixingangles (singlett, triplett) Klaus Peters – Open Charm Spectroscopy
q q Charm Productionat B-Factories • Resonant • e+e-γ*bb favoreddecay: b c W- • non-resonant qqproduction: e+e-γ*qq cc-eventsrichsourcefor D and Dsmesons d W+ c c b B0, B+, Bs q q Klaus Peters – Open Charm Spectroscopy
Heavy qq ordered by L approximate L degeneracy m(ηc)≈m(J/ψ) m(χc0…2)≈m(hc1) Light qq spectra as well same structure In Heavy-Light systems like H-atom ordered by property of the light quark approximate j degeneracy But the large gap between j=1/2,L=1 and j=3/2,L=1 was unexpected Heavy-Light Systems S=s1+s2 J=L+S M JP=0- JP=1- JP=0+ JP=1+ JP=2+ f2 χc2 f1 χc1 f0 χc0 h1 hc1 ω J/ψ η ηc not to scale L=0 L=1 M j=L+sL J=j+sH } j=3/2 DsJ* Ds1 DsJ* } j=1/2 Ds* DsJ Ds K. Peters - Charm Spectroscopy
D-Meson Spectrum • S-wavestates (L=0) • D0/D± Mark I, 1975 • D*0/D*±Mark I, 1975 • P-wave state candidates (L=1) • D0*(2400)Belle, 2004 • D1(2420)Argus, 1986 • D1‘(2430) Belle, 2004 • D2*(2460) E691, 1989 jq 1/2 1/2 1/2 1/2 3/2 3/2 mass L = 0 L = 1 Neutral and chargedstates Experiment Theory Godfrey,Isgur , Phys. Rev. D32, 189 (1985) Klaus Peters – Open Charm Spectroscopy
D-Meson Spectrum predictedbroadnarrow Decay S-wave, ~ q2L+1 q Decay D-wave ~q2L+1 q5 q breakupmomentum Mass / holds also for Ds Klaus Peters – Open Charm Spectroscopy
D0, D± - Production D0, 2006 First seen in continuumevents 232 fb-1 Phys. Rev. D74 091102 (2006) D0 Mark I, 1975 D0 D± showsthe extreme qualitiyofdata, which everynewgenerationhastocompetewith Klaus Peters – Open Charm Spectroscopy
D2*(2460) - Production First observed in γN(D)X In continuum e+e-(D)X Argus In B decays B (D*) B(D) E691, 1989 62 fb-1 Phys. Rev. D69 112002 (2004) progressis not asgiganticaswithlight D mesons reason: verycomplicated final state Klaus Peters – Open Charm Spectroscopy
D1(2420) – ProductionandDecays B-Decays B (D*), B (D) First observed in continuum e+e- (D*)X and D*D b) Argus, 1986 a) Argus, 1989 a) 62 fb-1 Phys. Rev. D69 112002 (2004) b) 145 fb-1 Phys. Rev. Lett. 94 221805 (2005) Angular analysis consistentwithspin 1 Phys. Lett. B232, 398 (1989) Klaus Peters – Open Charm Spectroscopy
D0*(2400) – Production, Parameters Usedecaypatternforindirect JPmeasurement Alloweddecaymodesfor JP = 0+ D 1+D* 2+ (D, D*) First observed in B (D) 62 fb-1 Phys. Rev. D69 112002 (2004) Focus (seen in γA) m = 2407 ±21 ±35 MeV/c2 = 240 ±55 ±59 MeV m = 2308 ±17 ±22 MeV/c2 = 276 ±21 ±63 MeV m = 2403 ±14 ±35 MeV/c2 = 283 ±24 ±34 MeV Onlydecaymode D JP = 0+favored Phys. Lett. B586, 11 (2004) 100 MeV difference 11P0 Klaus Peters – Open Charm Spectroscopy
D1(2430) – Production, Parameters… First seen in B decays 221 fb-1 Phys. Rev. D74 012001 (2006) B0(D*+-)ω B ±(D*) 62 fb-1 Phys. Rev. D69 112002 (2004) Color suppressed Color favored Noevidenceforthenarrowresonances at 2420 and 2460 MeV/c2 ? D1(2430) M = 2477 ±28 MeV/c2 = 266 ±97 MeV M = 2427 ±36 MeV/c2 = 384 ±117 MeV Onlydecaymode D* JP = 1+favored Klaus Peters – Open Charm Spectroscopy
Ds-Meson Spectrum cs+ c.c. 1/2 1/2 1/2 1/2 3/2 3/2 js States known until 2003 (CLEO, 1983) (PEP4, 1984) (Argus, 1989) (Cleo, 1994) L = 0 L = 1 Klaus Peters – Open Charm Spectroscopy
Ds-Meson Spectrum naturalspinparity cs+ c.c. 1/2 1/2 1/2 1/2 3/2 3/2 js States known until 2003 (CLEO, 1983) (PEP4, 1984) (Argus, 1989) (Cleo, 1994) Discovered after 2003 (BaBar, 2003) (Cleo, 2003) (BaBar, 2006) (BaBar/Belle 2006) L = 0 L = 1 Klaus Peters – Open Charm Spectroscopy
Ds0*(2317)+ - Production cccontinuumevents firstobservationofthisstateby BaBar in e+e-Ds+0+X B decays firstseen in B-decaysby Belle B Ds0*(2317)D, Ds0*Ds0 1) B Ds0*(2317)K 2) 368 fb-1 hep-ex/ 0507064 3) 232 fb-1 Phys. Rev. D74 032007 (2006) Bckgr. 1) Ds*Ds0 2) Ds*(Ds)+wrong 3) Ds1(2460) (Ds0)-missing Klaus Peters – Open Charm Spectroscopy
Ds0*(2317)+ – Parameters and Decays (PDG 08) Mass m = 2317.8 ±0.6 MeV/c2 Decaywidth < 3.8 MeV Verynarrow Observations - Mass too low compared with old potential models (Godfrey, Dipierro) New models work better - Mass lies below DK threshold only isospin-violating and electromagnetic decays possible Explanation of small width Klaus Peters – Open Charm Spectroscopy
Ds0*(2317)+ – Parameters Decaypattern Angular distribution B DDs0*, Ds0*Ds Ds0¤(2317)+ 261 fb-1 Belle Conf 0461 (2004) g,p0 Ds0 (B-CMS) B qH J=1 Ds (Ds0-CMS) J=0 Spin-Parity JP = 0+ Klaus Peters – Open Charm Spectroscopy
Ds0*(2317)+ – Nature of State • Molecular state? Search for Ds0*(2317)0andDs0*(2317)++companions • no signal in Ds+p- and Ds+p+ Isospin = 0 compatible with csstate Ds0*(2317)0Ds+p- Ds0*(2317)++Ds+p+ 2.317 232 fb-1 Phys. Rev. D74 032007 (2006) Klaus Peters – Open Charm Spectroscopy
Ds0*(2317)+ – Nature of State • Lots of tools • Production in B-decays (HQET) • Radiative production (Ds-cascade) • Radiative decays • Hadronic decays • Everything we know points to a cs state, • which is lowered in mass due to chiral corrections • But more exciting interpretations are still not excluded • need a flavor factory for more precise BR • Need a pp facility to measure or get better limits on the with • All this also holds for the next object in this talk Klaus Peters – Open Charm Spectroscopy
Ds1(2460)+ - Production cccontinuumevents firstobservationofthisstateby CLEO in e+e-Ds*0+X B decays firstseen in B decaysby Belle in B Ds1(2460)D B Ds1(2460)K 232 fb-1 Phys. Rev. D74 032007 (2006) 368 fb-1 hep-ex/0507064 Klaus Peters – Open Charm Spectroscopy
BUT – already in April 2003 BABAR Klaus Peters – Open Charm Spectroscopy
Ds1(2460)+ – Parameters andDecays Mass m = 2459.6 ±0.6 MeV/c2 Decaywidth < 3.5 MeV • Observations • Masstoolowcomparedwithold • potential models (Godfrey, Dipierro) • New modelsworkbetter • - Mass lies below D*K threshold (PDG 08) Missingmodes: morestatisticneeded 23 Klaus Peters – Open Charm Spectroscopy Klaus Peters – Open Charm Spectroscopy
Ds1(2460)+ – Parameters Angular distribution B DDs1 Ds1Ds Continuum, Ds1 Ds*0 J=1 JP = 0- J=2 JP = 1+, 2-, 3+, … J=1 261 fb-1 Belle Conf 0461 (2004) 232 fb-1 Phys. Rev. D74 032007 (2006) Spin-Parity JP = 1+ Klaus Peters – Open Charm Spectroscopy
Ds1(2460)+– Nature of State • Relative Branchingfractions Different branchingfractionsnot from same spindoublet Mixing angle Therearetwo 1+states, (Ds1(2460)+ , Ds1(2536)+) massdifferencem ~76 MeV investigationofmixingwith Ds1(2536)+ seemtobesmall ! Klaus Peters – Open Charm Spectroscopy
Ds1(2536)+ - Production cccontinuumevents firstseen in e+e- D*K, D*D B decays firstseen in B decaysby BaBarB D(*)D(*)K ARGUS 1989 DK, K D K0 347 fb-1 Phys. Rev. D 77 011102 (2008) Large signalsobservedverypreciseMeasurementsofmassandwidthpossible Klaus Peters – Open Charm Spectroscopy
Ds1(2536)+ - Parameters continuumeventse+e-(D*+K)X, D*+D0+ Large signalsPrecisemeasurementofmass, width PDG: 525.3 ±0.6 ±0.1 MeV/c2 First measurement of Ds1(2536) decay width: 232 fb-1 hep-ex/0607084 (preliminary) Klaus Peters – Open Charm Spectroscopy
Ds2*(2573)+ –ProductionandDecays First seen in cccontinuum CLEO 1994 100 events No angular distribution measured Decay mode consistent with 2+ 13P2 Inclusivestudyofe+e-(DK)X Large signal: Improvement in precisionforDs2(2573) Phys. Rev. Lett. 97 222001 (2006) 240 fb-1 Klaus Peters – Open Charm Spectroscopy
DsJ*(2700)+ - Production Seen by Babar in cccontinuum Inclusivestudyofe+e-(DK)X Seen by Belle in B+ → D0DsJ(2700)+, DsJ(2700)+→D0K+ Same state? Phys. Rev. Lett. 100 092001(2008) 414 fb-1 Phys. Rev. Lett. 97 222001 (2006) 240 fb-1 Klaus Peters – Open Charm Spectroscopy
DsJ*(2700)+ – Parameters final statenaturalspin-parity Phys. Rev. Lett. 100 092001(2008) 414 fb-1 preferred angular distribution JP=1- Possibleinterpretations - Radiallyexcited 23S1(excitedDs*) predictedmass ~2720 MeV/c2[ref 1] - Chiral doublet 1-stateto1+ Ds1(2536)+ predicted (2721 ± 10) MeV/c2 [ref 2] Confirmationneeded !! J=1 J=0 J=2 1) Godfrey, Isgur PRD 32, 189 (1985) Close et al., PLB 647, 159 (2007) 2) Nowak et al., Acta Phys. Pol. B 35, 2377 (2004) Important !! D*K andDs(*)η Klaus Peters – Open Charm Spectroscopy
DsJ*(2860)+ - Production, Parameters … Phys. Rev. Lett. 97 222001 (2006) 240 fb-1 First observed in e+e-(DK)X DsJ*(2860) Phys. Rev. Lett. 100 092001(2008) 414 fb-1 • DsJ*(2860) not seen in B decays. • highspinforthismeson ? • highspinsupportssmallwidth • D*K andDs(*)ηimportant final statenaturalspin-parity Klaus Peters – Open Charm Spectroscopy
Dalitzplot Analysis for D-Decays • Lorentz invariant, and phase space flat. • – Allows resonance parameters and spin to be well measured. • – Starts from a well-defined spin 0 particle • – Expect intermediate resonances to have J≤2 (because of limited two-body-mass range, and centrifugal barrier suppression) • – however, parity and isotopic spin are not conserved in the decay • •Charm Dalitz plots have many uses: • – New measurements in light meson spectroscopy • – Key role in CKM-measurement • – Fundamental information needed to understand heavy mesons decay • – Mixing and CP violation studies Klaus Peters – Open Charm Spectroscopy
D0 K0π+π- Relevant formeasurementofγ in BDK Belle BW, 2σresonancesbut χ2=2.72 arXiv:0803.3375, Phys.Rev.D73:112009,2006 Babar K-Matrix, χ2=1.11 487,000 events Phys.Rev.D78:034023,2008 Klaus Peters – Open Charm Spectroscopy
Model independent D+K-π+π+ E791Phys.Rev.D73:032004,2006 Kπ P-wave K ∗(892),K∗1(1410),K∗1(1680) Breit-Wigners. Kπ D-wave K∗2 (1430) Breit-Wigner. Kπ S-wave extracted by spline-interpolation over 40 points. At each point amplitude and phase are free parameters. c0(sk)eiφ0(sk) Kπ S-wave: Broad structure with dip at the K∗0(1430) resonance. Klaus Peters – Open Charm Spectroscopy
somemoredetails LASS curve normalized to the E791 data at 1.3 GeV. Phase normalized to the same mass shifting down by 700. Watson theorem requires elastic phase to be the same Klaus Peters – Open Charm Spectroscopy
Model independent D+π-π+π+ Phys. Rev. D 79, 032003 (2009) Klaus Peters – Open Charm Spectroscopy
Scalar studies in semileptonic D(s) decays orlν W M W M M M M M • Scalar waves are always problematic and unambiguous coupled channels are hard to identify (overlaps, crossings etc.) • New concept: Semileptonics Ds-decays Example: e+e- ψ(4040) Ds+Ds-and Ds+ • ππl+ν (π+π-, π0π0) • η(‘)η(‘)l+ν • KKl+ν (KSKS, K+K-) and l=e,μ • Model independent analysis possible • Use K-Matrix to analyze data • Coupled channel fit simple GSI - Group Report for BESIII@BEPCII
Outlook • for the D(S)-Spectrum • Necessary ingredients to differentiate among models • accurate total width measurements / partial decay widths hadronic and radiative transitions to Ds0*(2317)/Ds1(2460) from higher mass states test of mixing schemes • Tools ongoing BaBar / Belle / Cleo / CDF / D0 analyses high luminosity B-factories LHCb (Bs decays) charm production with pp @ PANDA @ FAIR (see T. Stockmanns) • for the hadronic (light) D(s)-Decays • ongoing BaBar / Belle analyses • may be soon be superseded by BES3 Klaus Peters – Open Charm Spectroscopy