Belle Hawaii activities in Belle New particles in BES & Belle S. L. Olsen
Belle highlights 2002-03 1 st measurement of φ 2 from B!π + π 1 st observation of B!K*l + l Discovery of a new charmonium state 1 st measurement of φ 3 (B!KD 0 Dalitz plot) Hint of new physics in B!φK S Measurement of Br(B!π 0 π 0 ) 1 st radiative charm decay D!φγ SM Belle has submitted/published 70 papers (30 since August 2002)
Papers primarily from Hawaii group New charmonium state (hep-ex/0309032) S.-K. Choi, S.L. Olsen et al., B!D CP K (hep-ex/0304032) S.K. Swain, T.E. Browder et al., (accepted by PRD) B B mixing with B!D*π (partial recon) PRD 67 092004 (2003) Y.H. Zheng, T.E. Browder et al., B!η c K* 1 st observation PRL 90, 071801 (2003) F. Fang, et al., B!hh PRD 66, 092002 (2002) B.C.K. Casey, et al., η c discovery PRL 89, 102001 (2002) S.-K. Choi, S.L. Olsen, et al., B!ppK 1 st observation (PRL --- F. Fang) A CP for B!h + h (PRD --- B. Casey) B-!K 1 (1270) J/ψ (PRL --- S.-K. Choi, S.L. Olsen))
Hawaii service in Belle TOF system (essential for all CPV studies) Calibration: Mike Jones Reconstruction: Mike Peters Tracking (essential to all analyses) Kalman filter (fitting): Karim Trabelsi K S!π+π selection: Fang Fang Trigger Level 0: Hulya Guler Level 1.5 (SVD-CDC matching): Kirika Uchida Background simulations (for SVD upgrade) Spent particles: Karim Trabelsi Synchrotron radiation: Sanjay Swain MC generator tuning: Rolf Seuster Event generation: Eric Dodson
Hawaii service in Belle (cont d) Utilities Run-by-run CM energy calibration: Sanjay Swain N(BB) determination: Sanjay Swain General event selection criteria: Brendan Casey SVD upgrade Electronics: Gary Varner Opto-Mechanical: Marc Rosen Software: Karim Trabelsi & Kirika Uchida Upgrades DAQ: Gary Varner & Yang Heng Zheng Pixels: Fang Fang Administrative Analysis coordinator: Tom Browder Co-spokesperson: S. Olsen
Other analyses underway CPV in B!D*ρ (Trabelsi & Peters) CPV in B!η c K S (Fang) CPV in B!D CP K (Swain, Kent) Charm fragmentation (Seuster) B!Kππ J/ψ & B! Kππψ ππψ (Guler) Search for 1 h c1 (i.e. 1 P c1 cc state) (Fang) B!η (980)X (Uchida) New particle searches (Olsen)
New particles in Belle & BES New state in B!K π + π J/ψ M ππj/ψ = 3872 MeV (= M D + M D* ) inconsistent with a cc state Low mass pp enhancement in J/ψ!γpp (BES) B! pp h (Belle) B Kpp??? J/ψ γ ψ γpp??? m(pp)
New state in B!K π + π J/ψ
DD* threshold DD threshold charmonium levels ψ ( 3 D c1 ) ψ 1 D c2 3 D c2 3 D c3 These are narrow if M<M D +M D* m=? η c 1 h 1? we found this last year in B!K K s Kπ η c η c J/ψ χ c0,1,2 cc level diagram:
B!K K S Kπ (η c studies) M bc for 40 MeV K S Kπ mass bins η c region what is this??? D c2!ggg? veto η c
Look for it in B!K π + π J/ψ (less background, better resolution) γχ c1 & B!K γχ 3 D c2!ππ J/ψ & γ χ c1 " allowed Γ(γ χ c1 ) > ~5 Γ(ππ J/ψ) 1 D c2!ππ J/ψ & γ χ c1 " not allowed
M(π + π l + l ) M(l + l ) ψ!ππ ππj/ψ?
M bc for 10 MeV M(ππ ππj/ψ) bins ψ!ππ ππj/y X!ππ ππj/ψ signal!!
Magnify signal region
E plots shows similar signal X!ππ ππj/ψ signal
3-d unbinned fit to ψ region (B!K ψ! K ππj/ψ) N ψ = 489 ± 23 events M bc M ππj/ψ E M bc =5279.1 ± 0.1 σ(m bc )=2.6 ± 0.1 M ππj/ψ σ(m ππ =3685.5 ± 0.2 ππj/ψ )=3.3 ± 0.2 E=-1.96 ± 0.4 σ( E)=11.6 ± 0.4 f_tail = 3.6 ± 1.5%
3-d unbinned fit to X(3872) region N X = 35.7 ± 6.8 events M bc M ππj/ψ E M bc =5279.1 (fixed) σ(m bc )=2.6 (fixed) M ππj/ψ σ(m ππ =3871.5 ± 0.5 ππj/ψ )=2.5 ± 0.5 E=-1.96 (fixed) σ( E)=11.6 (fixed) f_tail = 3.6 % (fixed)
reference mass to ψ M X = M meas (ππ ππj/ψ) M meas (ψ ) + M PDG (ψ ) M X = 3872 ± 0.6 (stat) ± 0.5 (syst) MeV This comes from comparing M meas (ψ ) with PDG value BW fit: Γ = 1.4 ± 0.7 MeV < 2.3 MeV @ 90% CL
M π+π tends to peak near limit background estimated from M bc - E sidebands
ρ!ππ + bkgd fits pretty well
Look for X(3872)!γχ an allowed E1 transition; should be > 5 X!ππJ/ψ (Eichten, Lane & Quigg) Select: B!K γ γ J/ψ: K and J/ψ same as before E γ >40 MeV plus π0 veto 15 < M γj/ψ -M χc1 <10MeV γχ c1 ( χ c1!γ J/ψ)
Do 2-d (M bc and M γχc1 ) fits γχ ψ region N evts = 34.1 ± 6.9 ± 4.1 events expect 26 ± 4 events (ψ!γχ c1! γj/ψ) M bc M γχc1
M bc and M γχc1 fits to X(3872) region γχ No signal!! M bc M γχc1 N X = 3.7 ± 3.7 ± 2.2 events (<9.2 events @ 90% CL)
Limit on Γ(X!γχ c1 ): Γ(X!γχ c1 )/ Γ(X!ππ ππj/ψ /ψ) = 0.35 ± 0.36 ± 0.21 < 0.89 @ 90% CL
Summary we see a ~10σ signal for B K X where: X! π + π J/ψ, M X = 3872.0 ± 0.6 ± 0.5 MeV; Γ<2.3 MeV (90%CL) Γ(X!γχ c1 )/Γ(X! π + π J/ψ) < 0.89 (90%CL) hep-ex/0309032! PRL is this the 3 D 2 cc charmonium state? Mass is too high (3872 vs 3810 MeV) Γ(X!γχ c1 )/Γ(X! π + π J/ψ) too small (<0.89 vs > 5) angular analysis is necessary (but hard). M X ~ M D0 + M D0*. =3871.3 ± 1.0 MeV could it be a D-D* bound state?
Low mass pp enhancement in J/ψ!γ pp (BES)
Use BESII s 58M J/ψ decays Select J/ψ!γpp 4-C kinematic fit de/dx for proton id non-pp bkg small main bkg from J/ψ!π 0 pp J/ψ!γη c ;η c! pp (calibration reaction)???? J/ψ!γpp
Study J/ψ!π 0 pp bkg with MC & data J/ψ!π 0 pp (data) J/ψ!π 0 pp!γpp (MC) three-body phase space Monte Carlo M(pp)-2m p (GeV)
Really protons and antiprotons de/dx pid verified by BSC response Not bkgd from J/ψ! hadrons No hint of peaking in J/ψ!π 0 pp data Not a QED background E γ pulls are symmetric cosθ γ distribution not peaked not seen in off-j/ψ data The signal is real
Fit to data acceptance weighted BW fitted peak location J/ψ!γpp M=1859 ± 3 +5-25 MeV Γ < 30 MeV (90% CL) χ 2 /dof=56/56 3-body phase space 0 0.1 0.2 0.3 M(pp)-2m p (GeV) acceptance
Is M peak really less than 2m p? weight events by q 0 /q: (i.e remove threshold factor) No turnover at threshold #peak mass must be <2m p M(pp)-2m p (GeV)
P-wave fit?? OK!! M=2m p!! M=1876 ± 3 +? -?? MeV Γ < 30 MeV (90% CL) χ 2 /dof=59/56
D-wave fit?? NG!! M=1885 ±? +? -?? MeV Γ < 30 MeV (90% CL) χ 2 /dof=1405/56
cosθ γ distribution 1+cos 2 θ γ (expected for J/ψ!γ0 + ) M(pp)<1.9 GeV sin 2 θ γ
include possible biases as (asymmetric) systematic errors (at least for now) M=1859 ± 3 +5-25 MeV Γ < 30 MeV (90% CL)
Summary A large enhancement seen near 2m p in the M pp distribution for J/ψ!γpp decays. Not apparent in J/ψ!π ο pp decays Not consistent with any PDG meson state If it is an S-wave resonance: M peak is below 2m p (M=1859 ±3 +5 25 MeV) full width is narrow (Γ<30 MeV) dn/dcosθ γ consistent with J PC = 0 + PRL 91, 022001 (2003)
Comments peak near but below 2m p : a pp bound state? narrow width: why so long-lived? similar patterns seen in baryon-antibaryon systems produced in B meson decays B!ppK B!ppD B!pΛπ B!pΛ c π
Belle sees low-mass pp systems in B decays F. Fang B ppk B ppπ M pp M pp B ppk S B ppk* M pp M pp
low-mass pp peaks in all (?) B!baryon decays B D 0 pp M pp
Strange & charmed systems B 0!pΛπ B!pΛ c π M(Λp) (GeV) (in these cases, the peaking doesn t seem to be right at threshold) M(Λ c+ p) (GeV)
hh bound states (hadronium)?? There is lots & lots of literature about this possibility deuteron: attractive nuclear force hadronium: attractive force?? + π n h h π loosely bound 3-q color singlets with M d = 2m p - ε loosely bound 3-q or q-q color singlets with M b = 2m p -δ
hadronic molecules a new spectroscopy?