Charmed mesons J. Brodzicka (KEK) for Belle Charm07, Ithaca US.
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Transcript of Charmed mesons J. Brodzicka (KEK) for Belle Charm07, Ithaca US.
Charmed mesonsCharmed mesons
J. Brodzicka (KEK) for BelleJ. Brodzicka (KEK) for BelleCharm07, Ithaca USCharm07, Ithaca US
OutlineOutline
• Introduction to cIntroduction to css multiplets multiplets• Observation of DObservation of Ds1s1(2536)(2536)→→DD++ππ--KK++
• Partial Wave Analysis of DPartial Wave Analysis of Ds1s1(2536)(2536)→→D*D*++KK00ss
• Observation of new DObservation of new DsJsJ(2700) (2700) →→DD00KK++ in B in B++→→DD00DD00KK++
• SummarySummary
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
DDs1s1(2536)(2536)1+
2+ DDsJsJ(2573)(2573)
D*K
D K
ccss multiplets multiplets• HQS based potential model predictionsHQS based potential model predictions• two doublets for orbitally excited L=1 ctwo doublets for orbitally excited L=1 css states: states: (Godfrey-(Godfrey-
Isgur ‘85)Isgur ‘85) 00++, 1, 1++ (j (jqq=1/2) and 1=1/2) and 1++, 2, 2++ (j (jqq=3/2) =3/2) M(jM(jqq=1/2), M(j=1/2), M(jqq=3/2) > M=3/2) > MDD+M+MKK Γ(jΓ(jqq=1/2) >> Γ(j=1/2) >> Γ(jqq=3/2) =3/2)
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
0+D*s0(2317)
1+
Ds1(2460)
L = 0 jq = 1/2 1-
0-
Ds*
Ds
spin-orbit tensor s-ospin-spin
jq = 3/2
jq = 1/2
L = 1
L = 2…..
JP
jq = sq + L, J = jq + sQ
mix
0+
?
?1+
Experiment:Experiment: jjqq=1/2 doublet =1/2 doublet
00++ : D : D**s0s0(2317)→D(2317)→Dssππ00
11++ : D : Ds1s1(2460)→D(2460)→D**ssππ00
jjqq=3/2 doublet =3/2 doublet
11++: D: Ds1s1(2536)→D(2536)→D**KK (Argus ‘89)(Argus ‘89)
22++: D: DsJsJ(2573)→DK(2573)→DK (CLEO ‘94)(CLEO ‘94)
jq=1/2 states:jq=1/2 states: very very narrow, masses below narrow, masses below DD((**))KK
→→ don’t match the don’t match the potential model potential model predictionspredictions
BaBar CLEO ‘03Belle
• Known decay modes of DKnown decay modes of Ds1s1(2536) : D*(2536) : D*++KKss, D*, D*00KK++, D, Dssππ++ππ--
• Study of eStudy of e++ee--→→DDs1s1(2536)X, D(2536)X, Ds1s1(2536)(2536)→→DD++ππ--KK++, D*, D*++KKs s
• 462 fb462 fb-1-1 data sample used data sample used (normalization mode)(normalization mode)
• xxPP=p=pDs1Ds1/p/pmax max >0.8 in e>0.8 in e++ee-- cms cms
• Two-body mass spectra consistent with Phase SpaceTwo-body mass spectra consistent with Phase Space
Observation of Observation of DDs1s1(2536)(2536)→→DD++ππ--KK++J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
BELLE-CONF-0706BELLE-CONF-0706
angular distribution studied for angular distribution studied for
this Dthis Ds1s1(2536)(2536)→→D*D*++KKs s samplesample
Mixing of jq=1/2 and jq=3/2 statesMixing of jq=1/2 and jq=3/2 states• HQET prediction for P-wave cHQET prediction for P-wave css states: states:
• 11++(j(jqq=3/2)=3/2)→D*K pure →D*K pure D-waveD-wave: D: Ds1s1(2536)(2536)→D*K →D*K • 11++(j(jqq=1/2)=1/2)→D*K→D*K pure pure S-waveS-wave: but D: but Ds1s1(2460)(2460)→D*K→D*K forbidden forbidden
• If HQET not exact: mixing of S-D waves possibleIf HQET not exact: mixing of S-D waves possible
(In D(In Ds1s1(2536)(2536)→D*K D wave suppressed →D*K D wave suppressed →→ small S-wave component can contribute much to the small S-wave component can contribute much to the
width)width)• Exp. knowledge on the mixing: Exp. knowledge on the mixing:
• from BF’s ratio of from BF’s ratio of DDs1s1(2460)(2460) radiative decays: radiative decays: D*D*ssγγ/D/Dssγγ=0.31 ± =0.31 ± 0.140.14
• switch from |switch from |jjqq>> to |to |2S+12S+1LLJ J >> basisbasis
• tantan22((θθ++θθ00)=0.8 ± 0.4)=0.8 ± 0.4 where tan where tan22θθ00=2 (no-mixing case)=2 (no-mixing case)
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
θ θ0
• Angular distribution depends Angular distribution depends
on on αα, , ββ, , γγ angles defined as: angles defined as:
• ρρ: helicity density matrix; : helicity density matrix;
ρρ0000: : probability of Dprobability of Ds1s1’s helicity=0 ’s helicity=0 ρρ1111== ρρ-1-1-1-1=(1-=(1-ρρ0000)/2 )/2
• √√RRΛΛ exp(i exp(iξξ)=A)=A1010/A/A0000 AA1010 , A , A0000: ampl. of D*‘s helicity= ±1, 0: ampl. of D*‘s helicity= ±1, 0
( A( A1010 = (S+D/ = (S+D/√2√2)/)/√√3 A3 A00 00 = (S-= (S-√2D√2D)/)/√√3 )3 )
D/S =√D/S =√ΓΓDD//ΓΓSS exp(i exp(iηη)) D, S: partial-wave ampl. in DD, S: partial-wave ampl. in Ds1s1 decay decay
• If no angle integrated If no angle integrated → → ξξ-dependent term survives-dependent term survives
Partial Wave Analysis of Partial Wave Analysis of DDs1s1(2536)(2536)→→D*D*++KK00
ss
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
BELLE-CONF-0706BELLE-CONF-0706
Fit to angular distribution of Fit to angular distribution of DDs1s1(2536)(2536)→→D*D*++KK00
ss• 3D maximum-likelihood fit with PDF:
• Background PDF: from M(D*+Ks) sidebands, normalized
• fbck: background fraction in M(D*+Ks) signal region: ~9%
• ε(α,β,γ)/<ε> → efficiency correction• Fit result projections (bckgd subtracted and efficiency
corrected):
• From χ2 of the fit: goodness-of-fit probability: 60%
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
Results of Results of DDs1s1(2536)(2536)→→D*D*++KK00ss PWAPWA
• Fit results (include systematic errors):Fit results (include systematic errors):
• ΓΓSS//ΓΓTOT TOT = 0.72 ± 0.05 = 0.72 ± 0.05 ((ηη=43.9 ± 1.7°=43.9 ± 1.7°))
S-wave dominates, contradicts HQETS-wave dominates, contradicts HQET
DDs1s1(2460) - D(2460) - Ds1s1(2536) mixing(2536) mixing
• DDs1s1’s helicity=0 preferred, agrees with HQET ’s helicity=0 preferred, agrees with HQET
(aligned production of j(aligned production of jqq=3/2 states is predicted)=3/2 states is predicted)
• First full analysis for P-wave charmed mesonsFirst full analysis for P-wave charmed mesons
(CLEO integrated over (CLEO integrated over ββ in PWA of Din PWA of D11(2420)(2420)→D*→D*ππ ))
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
(4160)
(3770)
New DNew DsJsJ meson in meson in BB++→→DD00DD00KK++
• b→cb→cccs tree process; cs tree process; css→D→D00KK++ and c and ccc→D→D00DD00 states can states can contributecontribute
• BB++→→DD00DD00KK++ signal identified using: signal identified using:
ΔΔE=EE=EBB-E-Ebeambeam , E , Ebeambeam=√s/2 : cms energy difference =√s/2 : cms energy difference
MMbcbc= √E= √E22beambeam-p-p22
BB : beam-constrained mass : beam-constrained mass
• S=399±40 S=399±40 for 449M Bfor 449M BBB pairs used pairs used• BF(BBF(B++→→DD00DD00KK++)=(22.2±2.2)=(22.2±2.2+2.6+2.6
-2.4-2.4) ) xx1010-4-4
• Dalitz plot and mass projections Dalitz plot and mass projections
different from 3-body Ph. Spacedifferent from 3-body Ph. Space
points: events from 1.5σ ΔE-Mbc signal box points: events from 1.5σ ΔE-Mbc signal box ■■:background from sidebands:background from sidebands
ΔΔEE MMbcbc
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
hep-ex/0707.3491 hep-ex/0707.3491
(submitted to PRL)(submitted to PRL)
new Dnew DsJsJ
• 2D ΔE-M2D ΔE-Mbcbc fits in invariant mass bins → B signal extracted fits in invariant mass bins → B signal extracted
• Obtained background-free mass spectra used to estimate Obtained background-free mass spectra used to estimate the resonance contributions:the resonance contributions:
fitted B signal fitted B signal yield yield
M(D0K+) for M(D0D0)>3.85 GeV fitted with: Breit-Wigner + ψψ(4160) reflection + Ph. Space (shapes (4160) reflection + Ph. Space (shapes from MC)from MC)+ exponential function (to describe the + exponential function (to describe the threshold enhancement (?threshold enhancement (?) ) ) )
Resonance contributionsResonance contributions
DDsJsJ(2700)(2700)
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
ψψ(4160) in (4160) in ½ helicity ½ helicity distr. distr.
ψψ(3770)(3770)
• Non-coherent approach; possible interference effects included in syst. errors
DDsJsJ(2700) (2700) →→DD00KK++ in in BB++→→DD00DD00KK++
• Helicity angle distribution ofHelicity angle distribution of DDsJsJ(2700): (2700):
background free and efficiency corrected background free and efficiency corrected
(reflections from threshold and (reflections from threshold and ψψ(4160) subtracted)(4160) subtracted)
• J=1J=1 preferred; 1 preferred; 1→→00--00- - decaydecay impliesimplies P=-1P=-1
• Contributions to the observed mass spectra Contributions to the observed mass spectra
• Most observed features well describedMost observed features well described
■■DDsJsJ(2700)(2700) ■■ψψ(3770)(3770) ■■ψ(4160)ψ(4160) ■■3body3body ■■threshold component threshold component
(MC predicted shapes)(MC predicted shapes)
fitted B signal yield fitted B signal yield
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
J=J=00 22//ndf=ndf=112112//55J=1J=1 22//ndf= ndf= 1111//5 5 J=2J=2 22//ndf=ndf=146/5146/5
DDsJsJ(2700) interpretation(2700) interpretation
• DDsJsJ(2700)→D(2700)→D00KK+ + 1 1-- state can be: state can be:
• radial excitation 2radial excitation 233SS11
(predicted by potential models at M~2720GeV)(predicted by potential models at M~2720GeV)
• chiral doubler state 1chiral doubler state 1-- to 1 to 1++ D Ds1s1(2536)(2536) (predicted from chiral symmetry considerations (predicted from chiral symmetry considerations
at M=2721±10at M=2721±10 MeV)MeV)
• BaBaR sees structure at M(DK)~2.69GeV produced BaBaR sees structure at M(DK)~2.69GeV produced
in ein e++ee-- continuum. Is that due to continuum. Is that due to DDsJsJ(2700)(2700)??
• DDsJsJ(2860) observed by BaBar not seen in our data. (2860) observed by BaBar not seen in our data.
Its production in B decays suppressed by its high spin?Its production in B decays suppressed by its high spin? BaBar Coll. PRL 97, 222001 (2006)BaBar Coll. PRL 97, 222001 (2006)
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
Godfrey, Isgur PRD 32, 189 (1985)
Close, Swanson PLB 647, 159 (2007)
Nowak, Rho, ZahedActa Phys. Polon. B 35, 2377 (2004)
SummarySummary
• New info to cNew info to css multiplets: multiplets:• new decay mode: Dnew decay mode: Ds1s1(2536)(2536)→D→D++ππ--KK++ oobserved bserved
• from PWA of Dfrom PWA of Ds1s1(2536)(2536)→D→D*+*+KsKs ((first full analysis for P-wave charmed mesons):first full analysis for P-wave charmed mesons):
• S-wave dominates: S-wave dominates: ΓΓSS//ΓΓTOT TOT = 0.72 ± 0.05= 0.72 ± 0.05
• DDs1s1(2536) and D(2536) and Ds1s1(2460) mix (2460) mix
• longitudinal polarization: longitudinal polarization: ρρ0000 = 0.490±0.013 = 0.490±0.013
→→ Falk-Peskin Falk-Peskin HQET parameter: HQET parameter: ww3/23/2 = 0.266 ± 0.019 = 0.266 ± 0.019
• new Dnew DsJsJ(2700) meson observed: (2700) meson observed:
M=2708M=2708±9±9+11+11-10-10MeV MeV ΓΓ=108±26=108±26+36+36
-31-31MeV JMeV JPP=1=1--
It opens a box of higher radial/orbital excitations of cIt opens a box of higher radial/orbital excitations of css statesstates
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
DDs1s1 recoil mass study recoil mass study
• Ds1(2536) recoil mass:
• Mrec spectrum indicates 2-body reactions:
e+e-→Ds1(2536)X, where X=Ds , D*s , higher D**s’s
• Mrec resolution: ~70MeV at 2GeV, 1/Mrec dependence
• 3D fits to angular distribution in bins of Mrec (RΛ and ξ fixed)
• Polarization at low Mrec:
show structures expected for:
e+e-→Ds1(2536)Ds , Ds1(2536)D*s
J. Brodzicka for Belle @ Charm07J. Brodzicka for Belle @ Charm07
• HQET Falk-Peskin parameter w3/2 (prob. of light quark’s helicities)• ρ00=2/3(1- w3/2) w3/2 = 0.266 ± 0.019 (w3/2 <0.24 @90%CL from D2*(2460)→Dπ by ARGUS)
Parameters: Parameters: ρρ0000, , RRΛΛ, , coscos ξξ