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					  Evidence for new Charmonium-like States
        from the BELLE Experiment



               Jens Sören Lange
(GSI, Johann Wolfgang Goethe-Universität Frankfurt)

          PANDA Collaboration Meeting
            Dresden, March 10, 2006




                                                      1
KEK-B Asymmetric Accelerator

                      E(e–)=8 GeV, E(e+)=3.5 GeV            Luminosity
                                                             start 06/1999
                                                             ~1/fb per day
                                                                 = 1.2 Mill. BB
                                                             integrated

                                                              BELLE 551 /fb
                                                              BABAR 324 /fb
                                                              CLEO ~10 /fb

                                                             peak
                                                            19.12.2005
                                                            L=1.63 x 1034 /cm2/sec
                                                            ~63%
                                                            above design goal
                        Tsukuba, Japan

Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006     2
B factories are well suited for charm spectroscopy

•   adjusted to Upsilon(4S), decays ~99% toBB
•   ~10% of time s=10.52 GeV in non-resonant continuum



                                              on-resonance:
                                              ~99% of B mesons
                                              decay into charm particles

                                              off-resonance:
                                              cross section is high




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   3
   On- vs. Off-Resonance: charmonium production




           on-resonance                                off-resonance
         J/ from B decay                          direct J/ production




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   4
J/ invariant mass




                       ~8-10 MeV




               s=10.58 GeV                            s=10.52 GeV
               on-resonance                            off-resonance
             J/ from B decays                     direct J/ production


Jens Sören Lange   Resonances Results from BELLE     PANDA, Dresden, 10.03.2006   5
Note

•   traditional wisdom:
    at e+e– machines one can only create
    JP=1– charmonium states
    (because e+e–  *  cc)
   only true for tree level:
       gluon radiation  spin 0,1,2,3 ...




                                         vs.




      also: part of data is two-photon fusion
       e+e–  **  ... (spin 0,1,2)
Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   6
                        The BELLE Detector                       asymmetric




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Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   8
Example events with charmonium final states

             J/e+e                                J/+




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   9
J/e+e–, +– invariant mass




                          8.9 MeV                           8.5 MeV




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   10
 Reconstruction of higher charmonium states




                        (2S)
                                                       cc1, cc2 → J/ 
                        → J/ +-
                                                                  cc1

                                                                        cc2




                         keep in mind
Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   11
Meson spectroscopy

•   V(r) ~ a 1/r + b r
    r small: Coulomb-like

                                                     n
    r large: confinement

•   excitations:

     • radial      n
     • orbital     L
     • spin        ,

•   Spectroscopic Notations


    n2S+1 L J                                                                   L
    JPC
Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   12
Potential Model


                                                              terra nova




                                                                            DD* threshold
                                                         ´                 DD threshold
                                              c´                     cc2
                                                                cc1
                                                    hc    cco


                                                    J/   „ORTHO“
                                              c          „PARA“



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The Fluxtube in a Meson

  [ qq ] bound state

strong interaction strength




          0.7 fm                      1.0 fm                        1.35 fm


Lattice QCD calculations
G. Bali, hep-lat/9409005

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Highly Excited [ qq ] States as seen by Lattice QCD

•   fluxtube becomes thinner and might break earlier

strong interaction strength




G. Bali, hep-lat/0510051

Jens Sören Lange    Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   15
Are there maybe additional gluonic excitations ?

•   glueballs [gg ]
    or
    hybrids [ccg ]
•   only Lattice QCD
    is able to answer
•   hep-ph/0412158




                                                   note:
                                                   no 1++ glueball


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                                c´ (21S0)


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c´ candidate seen 1982 by CRYSTAL BALL

•   Phys. Rev. Lett. 48(1982)70
     recoil
    35925 MeV
     (~50 MeV too low
    for potential models)
•   never confirmed


                                    ´X




                                   J/X


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Observation at BELLE 2002

•   excited singulet charmonium   c(2S)
•   observation in B decays
•   Phys. Rev. Lett. 89(2002)102001
•   44.8 Mill. BB
•   m=365468 MeV
    (close to potential models)
•    c´  e+e– not allowed (spin 0),
     c´  gg (hadronic) allowed
•   charm  strange dominant
    hence search in channels
    with Kaon final states
      [s s] 
    here: Ks K 
•   note: ´ seen only 3 weeks after J/,
    c´ 24 years after c

Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   19
Confirmation by CLEO and BABAR

•   not in B decay, but  fusion




        Phys. Rev. Lett. 92(2004)142001          Phys. Rev. Lett. 92(2004)142002

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c´ observation in double charmonium production
   3rd production mechanism                                     J/
   BELLE off-resonance
   Phys. Rev. D 70(2004)071102
   e+e  cc cc                                               recoil
   recoil mass against J/
   note:
    charge conjugation                             c cc0 c(2S)
    forbids J/ J/
    (see also
    PRD 70(2004)071102
    for e+e–**
    hypothesis)




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                                  X(3872)




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The J/ +– final state

   A golden event
    of a CP violating decay

    Bo  J/ Kso

        J/   +–
    (here J/+–)




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   23
   Evidence for a new state X(3872)




               ‘(3686)




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                             X(3872) Confirmation


                   9.4




                                            11.6


Phys. Rev. Lett. 91(2003)262001
152 Mill. BB
                                                    BABAR



                                         hep-ex/0406022



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    Agreement among 4 Experiments


 Average m=3871.90.5 MeV/c2
 Widths consistent with resolutions
  <2.3 MeV (BELLE)




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What is the X(3872) ?




                                                                             X(3872)
                                                        DD* threshold
                                     ´                 DD threshold
                          c´                     cc2
                                            cc1
                                hc    cco


                                J/
                          c



Jens Sören Lange   Resonances Results from BELLE           PANDA, Dresden, 10.03.2006   27
What is the X(3872) ?

•   final state J/
•   m() clusters around  mass

•   enables identification of
    C parity
    for bosons, total wave function
    must be symmetric

     • I=1
       L()=1, JPC()=1– – (-like)
        CX(3872)= +
     • I=0,2
       L()=0, JPC()=0++
        CX(3872)= –




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   28
                                                         BR is factor ~10
                                                         smaller than
                                                         XJ/+–


                                                                 4



Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   29
X(3872) possible quantum numbers

   BKX decays
    spin 0 spin-0 X
    high L=2,3,... suppressed
   but test anyway
    consider D wave states (L=2)

    2   13D2      2     m~3838 (predicted)
    3   13D3      3     m~3849 (predicted)

    should have a dominant radiative decay(s)

    X cc1(13P1, 3511)
    X cc2(13P2, 3556)

    „easy“ L=2L=1 transitions
    by  emission


Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   30
X(3872) possible quantum numbers

Test upon

      2 13D2




                                                                ‘(3686)




answer: no.
                                                                X(3872)
Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   31
X(3872) possible quantum numbers

Test upon

      3 13D3




                                                               ‘(3686)




answer: no.
                                                               X(3872)
Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   32
X(3872) possible quantum numbers

   Remember:
    above DD threshold
    (3740 MeV)
   but
    XDD not observed

    BR(XDD) / BR (XJ/+–) < 7
    (90% CL)
    BELLE, hep-ex/0307061

    forbidden / suppressed ?

   disfavours
    [DD ] quantum numbers
    JP=0++, 1– –, 2++, ...



Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   33
Why is the X(3872) narrow ?


   about one pion mass above DD threshold
    and be narrow anyway ?

      few states are predicted narrow
       if decay into DD is blocked

          J=1, if predicted mass below threshold
           1+– 11P1
          J=2, parity breaking
           2– – 13D2 (2) , 2–+ 11D2 (2c)
          J=3, angular momentum barrier
           (13D3 must get rid of L=3 for decay to DD spin-0 spin0)




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   34
X(3872) possible quantum numbers

•   0–+ and 1++ are still options

    consider a 0–+ radial excitation

    c´´(31S0,0+)

    m~4060 in potential model

    (predicted mass too high,
    but consider anyway)

    should be seen in  fusion (as c , c´)
    negative search
    CLEO, Phys. Rev. Lett. 94(2005)0032004

•   answer: no.


Jens Sören Lange     Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   35
Does the X(3872) decay into DD(*) ?
                                                                                NEW
            DD not seen, but DD seen !
   BR(BK X)BR(X+-J/)          =1.31±0.24±0.13 10-5
   BR(BK X)BR(XJ/)             =1.8 ±0.6 ±0.1 10-6
   BR(BK X)BR(XDD)             =1.6 ±0.4 ±0.3 10-4

   this is 12.55 x more than the original observation
    so we can‘t say anymore that decay into DD*            BELLE Preliminary
    is (maybe) suppressed
•   note:                                             N=12.5±3.9
    although D* D   o 
                                                      (>5)
    X D D*
    X D D 
    mean different decay dynamics
    0- 1-
    0- 0- 0-
     orbital angular momentum L=1 !


Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006    36
X(3872) possible quantum numbers

   1++ is a likely assignment.

   Is there a 1++ ? Yes.

    cc1´(23P1)

   but inconsistent with potential model
    m~70 MeV higher predicted

   Preliminary conclusion:

    the X(3872) might not fit into a naïve potential model

    Not resolved yet.



Jens Sören Lange    Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   37
                                 X(3940)




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   38
Revisited: double charmonium recoil mass (off-resonance)

       L=101 fb-1     2002



                                                    2004    L=287 fb-1




      L=155           2003
          fb-1




Jens Sören Lange    Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   39
Another one, X(3940)

   350/fb
   no signal of X(3872)
   significant peak at M=3.9400.011 GeV/c2
       N=14833 events (4.5)
       width is surprisingly narrow <~ resolution (= 32 MeV)
   background curve:
    2nd order polynomial
    plus D(*)D(*)J/                                    c cc0 c´
    threshold term
   so far only spin-0 particles
    in recoil mass
    c´´ ?
    inconsistent to
    potential model m~4060 MeV                                     2005
    (should be accurate
    for S=0, L=0)

Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   40
Does the X(3940) decay into DD(*) ?

   BELLE, 357fb-1, hep-ex/0507019, subm. to Phys. Rev. Lett.
   reconstruct J/ + one D
    then investigate recoil mass
   X(3940)→D D
    not seen
   X(3940)→D(*)D                               Mrec(J/ D)=M(D)
    seen !
   „normal“ charmonium (?)


                                                 Mrec(J/ D)=M(D*)
                                         24.5±6.9
                                         evts
                                         5




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   41
   Coming back to the X(3872) for a moment

   Evidence for X(3872)+0 J/ (sub-threshold)
   (hep-ex/0408116)




                                    a virtual (782)?
                                                                12.4 ± 4.2 events




   Br(X3J/)                                  large (near max)
   Br(X2J/) = 1.0 ± 0.5                      isospin violation

Jens Sören Lange      Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   42
Another one, Y(3940)

   extend range to higher m(J/)
   Phys. Rev. Lett. 94(2005)182002
   253/fb
   394311(stat.)13(syst.) MeV
    width 872226 MeV
   significance 8
   fit: s-wave Breit-Wigner
    plus phasespace-like
    threshold function
   let‘s try to be inventive:
    not call it X
   A charmonium thus high should
    dominately decay into DD
    (and not J/)
    why is it blocked/suppressed ?


Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   43
Investigate other possible decay modes

   Y(3940)J/ is not seen
    vs. : additional [ss] in wave function
   might rule out tetraquark [cc ss] concept



                                             PRL 93, 041801




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   44
Yet another one at same mass, Z(3930)
                                                                hep-ex/0507033
     DD,  D+D–
   BELLE Phys. Rev. Lett. 96(2006)082003
   280/fb
   m=3931±4(stat)±2(syst) MeV
    =20±8±3 MeV
   5.5
    can couple to 0,1,2
    only candidates: n3P0 and n3P2
    (excited S states known and
    n3P1 dominately decays radiative, J((*))=1)
   *(D)
    J=0 flat
    J=2 ~sin4*
   might be 1st observed radial excitation
    of a P charmonium state: 23P2 c'c2
    (only n3S, n1S seen so far)

Jens Sören Lange    Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   45
Implications for PANDA

   if parity +, then can be produced with 2 gluons: „enhanced“


     1–
                                                                  1+
     J/,‘
     Y(4260)                                                      X(3872)



   X(3872) only seen in B decays
    production of X(3872) at CBM (pp, SIS300)
    might have similar cross section (~nb)
    as PANDA
   none of the new states has been
    in the BELLE TDR




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   46
Conclusion

   B factories observe several new states
      c´                    BELLE
      D*(2308)               BELLE
      D1(2427)               BELLE
      DsJ(2317)              BABAR
      DsJ(2460)              CLEO
      X(3872)                BELLE
      X(3940)                BELLE
      Y(3940)                BELLE
      Z(3930)                BELLE
      c(2800)               BELLE
      hc                     CLEO
      Y(4260)                BABAR
   some of them quantum numbers unassigned yet
   with increasing statistics additional observation are uninevitable


Jens Sören Lange    Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   47
Another one, Y(4260)

   BABAR hep-ex/0506081
   initial state radiation events e+e J/+–
    (tag: undetected  parallel to beam axis in beampipe)
   211/fb
   mass 42598+2–6 MeV, width 8823+6–4 MeV
   significance >8
   (4040), (4160), (4415) not seen
   intriguing fact:
    again close to a threshold
    D*o(2007) D2*o (2460)
   tentative assignment
    (based upon production
    mechanism)
    1– –
     note: allowed for DD


Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   48
Y(4260) not seen in energy scans

   e+e–  inclusive hadrons




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   49
Y(4260) Confirmation by CLEO

   energy scan
    not inclusive hadrons, but J/+–




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Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   54
                                               hc (1P1)




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                                    D**




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   56
D**

•   assume heavy quark symmetry
    mcharm

•   light quark couples to L first

•   then
    L=1 states are 2 doublets

    jq=1/2
    broad (decay by  S wave)

    jq=3/2
    narrow (decay by  D wave)




Jens Sören Lange     Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   57
D**

•   BELLE observes the two broad D** (jq=1/2) states          D+K+
    Phys. Rev. D69(2004)112002                                D*+Do+
    65.4 Mill. BB                                             DoK+
•                 mass                      width             DoK++
    D*0(J=0)      2308171528 MeV         276211860 MeV
    D´1(J=1)      2427262015 MeV         384+107-752470 MeV




                                                                 D2* can decay
                                                                 to D and D*




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006    58
                                      DsJ




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   59
Unexpected observations in 2003 in e+ecc

•   BABAR observed DsJ+(2317)Ds+ o      Phys. Rev. Lett. 90(2003)242001
•   CLEO observed DsJ+(2460)Ds+*o       Phys. Rev. D 68(2003)032002
•   Ds final state
    > most probable assignment
    [c s] L=1 states
•   narrow (<4.6 MeV and <5.5 MeV, respectively)




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Confirmation

•   BELLE confirmed both
    and observed DsJ+(2460)Ds+      Phys. Rev. Lett. 92(2004)012002
•   seen in both production mechanisms
     • e+ecc
     • B decay > important for determination of quantum number




                                                                not Ds* !

Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   61
DsJ quantum numbers

•   observation in B decays enables helicity analysis (fixed initial state)




       JP=0+                                                       JP=1-




Jens Sören Lange    Resonances Results from BELLE    PANDA, Dresden, 10.03.2006   62
Compare D and Ds systems

•   should be similar (except smaller mass splitting jq=1/23/2
    due to s quark mass
•   why are the Ds jq=1/2 states narrow (and the D states broad) ?
    isospin violation (from I=0 to I=1)
•   but measured DsJ masses >100 MeV lower than potential model




                                                       Theory




                                                       Experiment




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                           Charmed Baryons




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   64
Charmed Baryons

•   (u/d, u/d, c) baryons
    known states
                                                    c(2455)
                   I(JP)
    c(2285)       0(1/2+)
    c(2455)       1(1/2+)
    = isospin excitation
    c(2520)       1(3/2+)                          c(2520)
    = spin excitation

    no  orbital excitations
    observed yet

•   cpK–+
    cpKs
    c+


Jens Sören Lange    Resonances Results from BELLE    PANDA, Dresden, 10.03.2006   65
           Isotriplet




                        281/fb




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   66
co,+

•   BELLE 140/fb
•   Phys. Lett. B 605(2004)237
•   three new decay modes (of seven observed)




•   search for co,+ excited states is underway


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                               Additional Slides




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X(3872)J/+– candidate selection




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   69
Title




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   70
Lattice QCD

•   hep-ph/0412158




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Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   72
On- vs. Off-resonance

         on-resonance                              off-resonance
          (B decay)




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   73
                                                                           BELLE
B factory detectors


                   CLEO




                                                                           BABAR




Jens Sören Lange    Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   74
since
1999

                                                                                    before
                                                                                    1999




    Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   75
Another DsJ ?

•   SELEX, 600 GeV hyperon beam (~50% -) on Cu target
•   peaks at m~2632 MeV seen in both
    m(Ds+) and m(Do K+) (where known Ds2(2573) is seen as well)




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   76
Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   77
 Investigation of the  system (cont’d)

 M() can distinguish -J/ S- & P-waves

      S-wave: c2/d.o.f. = 43/39                P-wave: c2/d.o.f. = 71/39
      (ignoring D-wave)                        (ignoring F-wave)

     BELLE                                   BELLE




                             ~q*(J/)                                  ~q*3(J/)


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Investigation of the  system (cont’d)
M() can distinguish -J/ S- & P-waves
Indication for S-wave supported by CDF




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   79
Double charmonium production
   e+e– cccc X
   off-resonance (direct production)
   even production of 4 charm quarks seen
    e+e– cccc X
   cross section is enhanced
    e.g. e+e–J/c
    ~ factor 12.8 higher than expected




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   80
                                                       hep-ex/0206002
The direct J/ enigma                                  PRL 89(2002)102001


Theorie                                                    Experiment
                                                                         2 gluons:
dominant ~ 1 pb                                            negligible    color-singlet or
                                                                         color-singlet

dominant for high p*(J/)
~ 0.5 pb
                 p*(J/)


                                                           not seen      1 gluon
                                                                         only color-octet

   0      1   2    3   4    5 GeV/c

suppressed
(2 x charm quark mass)                                     dominant ~ 80%



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•   3 enigmä:

    - cross section factor ~10 too high
    - 60% of cc is rather cccc (contradicts 1/S)
    - no color-8 contribution seen

•   color-8 can give more charmonium
    a bound [cc] must be colorless
    but an intermediate cc pair might be color-8
    (in other words, it is colored)
    the color-8 state radiates a gluon, and thus becomes colorless




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   82
Is it QED and not QCD ?

   Braaten et al. noticed
    Phys. Rev. Lett. 90 (2003) 162001
    that in none of
    the previous calculations
    2 photon diagrams
    were taken into account




   But this would mean:
    we must see: J/ J/




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   83
Are there coupled channel effects ?

•   beyond naïve potential model
•   Brambilla et al., hep-ph/0412158
•   intriguing fact
    X(3872) mass is very close
    toDD* threshold
    within errors +0.51.1 MeV
•   near threshold
    Schrödinger states are not pure
    potential model eigenstates,
    but



    (sub-threshold, virtual)
•   induces mass shifts



Jens Sören Lange    Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   84
hc also observed

•   CLEO hep-ex/0505073
•   e+e–(2S)ohc, hcc
•   3.08 x 106 (2S) decays
•   m=3524.40.60.4 MeV
•   significance > 5
•   mass consistent with spin-weighted average of ccJ
    (and only 1.8 MeV lower than non-confirmed E760 signal in 1992)




                                            mrecoil(o)
Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   85
Cross sections at RHIC.
 SPS s=17.8 GeV, RHIC s=130, 200 GeV
   (cc)~factor 102, (bb)~factor 103 higher

                          cc
                                                               bb
         (pp-->cc)[b]




                                                                      pQCD
                                       R. Vogt
                               hep-ph/0205330
                               100        1000   10000
                                     s [GeV]




Jens Sören Lange               Resonances Results from BELLE    PANDA, Dresden, 10.03.2006   86
DD

• X(3872)
  -> DD         not seen
  -> DD*        not seen
  -> DD        seen
• Y(3940) = the J/Psi Omega enhancement
  -> DD not seen
  -> DD* not seen
  unlikely to be seen because J/Psi Omega decay is so strong
• X(3940)
  -> DD not seen (in J/Psi D recoil)
  -> DD* seen !




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   87
test




Jens Sören Lange   Resonances Results from BELLE   PANDA, Dresden, 10.03.2006   88

				
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