new particles from belle
DESCRIPTION
New Particles from Belle. S. L. Olsen ( U. of Hawaii). GHP 2004 Fermilab, October, 2004. B-factory bonuses:. new insights/puzzles in charm/charmonium spectroscopy. B K K s Kp. h c ’. B K p + p - J/ y. X(3872). M(K s K p ). M( p + p - J/ y). e + e - J/ y cc. B K w J/ y. - PowerPoint PPT PresentationTRANSCRIPT
New Particles from BelleNew Particles from Belle
S. L. OlsenS. L. Olsen((U. of Hawaii)U. of Hawaii)
GHP 2004 Fermilab,GHP 2004 Fermilab, October, 2004October, 2004
B-factory bonuses:
new insights/puzzles in charm/charmonium
spectroscopy
c’
X(3872)
M(KsK)
BK Ks
BK +-J/
M(+-J/
ccc0
J/recoil mass
e+e-J/cc
??‘
BK J/
M(J/
??
bccs is a dominant process
b
c
c
s
Vcb
cosC
J/, ’, c, c1,…
Brs~10-2
(inclusive)
CKMfavored
W-
B mesons are a good source for charm charmonium and other cc states
>900pb-1/day(~1M BBs/day)
1.2x1034/cm2/s
KEKB is a good source of Bs
Kinematic variables for the (4S)
CM energy difference:
Beam-constrained mass:
22 )()2( 'c
ppEm KCMbc
BK c
BKc
2/' cmK EEEEc
B
Bϒ(4S)
Ecm/2
e e
Ecm/2
KSK
KSK
Mbc
E
1st Observation of the c‘
BK (KSK±Ŧ)Mbc for 40 MeV M(KSK) slices
3000 MeV
3640 MeV
BK c
BK c’42fb-1
KSK
KSK
Fit each bin
Nevt = 45.3 ± 12.6 Mc’ = 3653 ± 10 MeV
c’ = 33 ± 22 MeV
Nevt = 90.5 ± 14.9 Mc = 2978 ± 5MeV
c = 33 ± 16 MeV M(KSK)
Mbc E
c:
c’:3.55 GeV
3.60 GeV
3.65 GeV
3.70 GeV
3.75 GeV
…
…
Subsequent measurementsconfirm higher mass value
KSK
KSK
eeJ/X
Mx
BaBar(preliminary)
3630 MeV
3642 MeV
3633 MeV
CLEOhep-ex/0306060
elle
c c‘
c’: current status
Mavg =3637±4 MeV(Crystal Ball excluded)
M(1S) = MJ/ – Mc = 117±1 MeV
M(2S) = 49 ± 4 MeV
smaller
The X(3872) with 253 fb-1
B±K±+-J/ (275M (4S)BB decays)
Nev = 48.6 ± 7.8M = 3872.4 ± 0.7 MeV(width consistent with resol)
Mbc for 5 MeV M(J/) bins
Now M( is really -like
background estimated from Mbc-E sidebands
Confirmed by CDF & D0
PRL 93, 262001(2003) hep-ex/031202
X(3872) X(3872)
CDF D0
hep-ex/0405004
3.5 σ effect
also seen by BaBar
M=3873.4 ± 1.4 MeVB(BKX)B(XJ/) = (1.28± 0.24) x 105
Belle (1.3± 0.3) x 10-5
hep-ex/0406022
X(3872) Mass
D+D*- threshold
(Plot from Soon Yun Jun’s FPCP04 CDF hot topics talk)
Charmonium possibilities
J/c
c’ ’
”
hc
c0c1
c2
c”
hc’c1’
c2
2 3
cc level spectrum
3872 MeVMD+ MD*
2MD
No obvious cc candidates for X(3872)
c”
hc’
c1’
2
c2
3
M too low; too small
c should dominateJ/
J/ decays violate isospin
angular dist’n rules out 1
M too low;J/ too small
c too small; m wrong
c& DD) too small; m wrong
Look at BK J/
M()
M(J
/ )
BK J/
XJ/ BK X(3872);
1: look at BK J/Dalitz Plot
M
Mbc
EM
2(J
/
)
M2(K)
BK* J/K
cut here
Slice into 40 MeV-wide M(J/) bins
Large deviationfrom phase-space
Fit
Slice into 40 MeV-wide M(J/) bins
Adding a BWhelps
FitM≈3940 ± 11 MeV≈ 92 ± 24 MeV
M(K) for the signal region
M(K) (GeV)
3880 <M(J/)<3900 MeV
No peakingIn M(K)
Look back at the masses
76’s28’s
Very clear signal
20’s26’s
What is it? Charmonium?Charmonium?
– Conventional wisdom: J/ should not be a discovery mode for a cc state with mass above DD & DD* threshold!
Some kind of Some kind of -J/-J/ threshold interaction threshold interaction??
– the J/ is not surrounded by brown muck; can it act like an ordinary hadron?
cc-gluon hybrid?cc-gluon hybrid?– Predicted by lattice QCD, including states with large hadron+cc widths,
but the masses are predicted to be 4.3 ~ 4.4 GeV
J/
Evidence for X3872K J/
M(J/) vs M() revisited
M()
M(J
/ )
BK X(3872)
J/
look along here
M(3 J/) = MX(3872) ± 16.5 MeV(±3)
Look at 25 MeV-wide M() mass bins
E Mbc
B-meson yields vs M()
12.4 ± 4.2 evts
“Sidebands”
BKJ/Non-resonant
or “peaking bkgdsidebands
Overlapregion
Cross-talk from BKJ/enhancement?
f dm = 0.75 ±0.14 evts
Check : signal yield for M(3 J/)= M X(3872) +1–3(no overlap with band) 12.4 evts 11.5 evts (expect 11.0 for no X-talk)
Other sidebands(no significant signals)
4.3 ±6.2 evts
6.4 ± 5.6 evts
Area of I and III each= 4x Area of signal bin
Non-res bkd in signal bin = 1.3 ± 1.0 evts
M(K3) for signal bin
Branching fraction
Br(X J/)Br(XJ/)
Nev( J/) (2J/)Nev(J/)(3J/)
=
0.188
0.036
12.4 ± 4.2
62.6 ± 8.3
= 1.1 ± 0.4 (stat) ± 0.3 (syst)
Accept:ance: 10%Xtalk/Bkgnd: -20%X J/: +25%M(3)<750 MeV
significance ≈ 4
Consistent with sub-threshold X(3872) J/
MM + M + MJ/J/ = 3879 MeV (7 MeV above 3872) = 3879 MeV (7 MeV above 3872)
– X J/ occur via virtual ’s, 3 masses cluster at the kinematic limit.
(X(XJ/J/)/)/(X(X J/ J/) = 1.1±0.4 ± 0.3) = 1.1±0.4 ± 0.3
In agreement with Swanson’s DD* bound-state model for the In agreement with Swanson’s DD* bound-state model for the X(3872)X(3872) [PLB 588,189 (2004)][PLB 588,189 (2004)]
Smoking gun for qqqq interpretation of X(3872)?Smoking gun for qqqq interpretation of X(3872)?
- -
continuum e+e-J/ (cc) with 287 fb-1
Details in Tom Ziegler’s talk in session B3Sunday, Snakepit 5:08PM
L=101 fb-1
2002L=155 fb-
1
2003
287 fb -1
c c0
‘c
4th peak!!non-zero continuumbelow DD threshold
• J/ J/ negligible
• confirm c’
• e+e-J/ (cc) > e+e-J/ glue
• (e+e-J/ c) > 10x theory
• evidence for c’ 2004
-
What is the 4th peak?the reconstruction and selection procedure is the same the reconstruction and selection procedure is the same as beforeas before
Extend the fit regionExtend the fit region
no signal of X(3872)significant (>4) peak at M=3940 11 MeVN=14833 (4.5)the width is consistent w/ resolution (= 32 MeV)
X(3872)
c
c
c0
c‘
‘
What is it? c0? c ??‘ “
Look at e+e-J/ D(D(*))
•Reconstruct a J/ & a D•use D0K-+ & D+K-++
•Determine recoil mass
Look at M(DD(*))
DD*
DD
3940 MeV
9.9 ± 3.3 evts(4.5 )
4.1 ± 2.2 evts(2.1 )
c0 DD*‘
c DD“
What is this one?
Is it too narrow to be the same as the Is it too narrow to be the same as the J/J/ peak at 3940 MeV??? peak at 3940 MeV??? under investigationunder investigation– We are looking for J/ recoiling from a J/ in the continuum
– & BK “Y(3940)”; “Y(3940)”DD*
c0c0 or or cc most likely charmonium states most likely charmonium states
– DD* signal rules against c0
– Mass is a little low for c
• M(3S) would be ≈ 100MeV
• can M(3S) > M(2S)?
‘ “
“‘
JP of the DsJ(2317) and DsJ(2457) from BDsJD decays
Details in Alexey Drutskoy’s talk in session C1Monday, 1-West 2:36PM
DsJ(2317) Ds*0
DsJ(2317) Ds0
DsJ(2317) and DsJ(2457)
BaBar - DsJ(2317) CLEO
DSJ(2317)
DSJ(2457)
KKDS
0 KKDS
Masses are significantly lower than potential model P-level predictions - speculations about 4-quark, DK-molecule and Dsπ atom, csghybrid…
DSJ(2317)
M(Ds0)
M(Ds0)
M(Ds*0)
DsJ(2317)Ds0
DsJ(2460) Ds* 0
DsJ(2460)D s
BelleDSJ(2317)
DSJ(2457)
DSJ(2457)
DsJ properties are consistent with two lowerst P-level states
DsJ(2457) consistent with JP=1+ DsJ(2317) consistent with 0+ No Ds0 decay rules out 0+,1- Flat decay angle distribution Ds decay rules out 0+,0- No Ds+ - and Ds decays Helicity in BD DsJ(2457) prefer J=1
J=1
J=2
J=1
J=0
DsJ(2317) Ds0
DsJ(2460) Ds
DSJ(2317)
DSJ(2457)
B D DsJ(2317) (and DsJ(2457))
Summary
cc’ established ’ established M(2S) < M(2S) < M(1S) M(1S) (as expected)(as expected)
(X(3872)(X(3872)J/J/ ≈ ≈ (X(3872) (X(3872) J/J/))– good for molecules; bad for charmonium
Broad near-threshold Broad near-threshold J/J/ peak at 3940 MeV peak at 3940 MeV– too broad for charmonium– too light for cc-glue hybrid?– threshold interaction involving a J/ ?
Narrow(?) peak at 3940 in e+e- Narrow(?) peak at 3940 in e+e- J/J/ X recoils X recoils– May be too narrow to be the J/ state seen in B decays– seen in DD* (rules out c0’)– mass too low to be thec”
DDsJsJ consistent with J consistent with Jpp=0=0++ for D for DsJsJ(2317) (2317) and Jand Jpp=1=1++ for D for DsJsJ(2457)(2457)
Backup Slides
Other results on the X(3872) - Look for X(3872)c2 ( c2
- J/- J/ helicity angle dist inconsistent with J helicity angle dist inconsistent with JPCPC = 1 = 1
- rules out X=21P1 (hc’)
Mbc Mc2
X
2=75/9
|cosJ/
(Xc2)(XJ)
<1.1
- Contrary to expectations for charmonium 3D3
expect: dNdcosJ/
sin2
BKc1; c1J/
no X(3872)Br(XJ/)
Br(XJ/) <0.4
Probably not the c1’
M( J/)-M(J/)
90% CL upper limit:
BK J/
Other new results on the X(3872), cont’d