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Ted Barnes Physics Div. ORNL Dept. of Physics, U.Tenn. GHP2004 Fermilab, 24-26 Oct. 2004. Higher Charmonium. Spectrum Strong decays (main topic) L’oops. abstracted from T.Barnes, S.Godfrey and E.S.Swanson, in prep. 1. Spectrum. Charmonium (c c ) A nice example of a Q Q spectrum. - PowerPoint PPT Presentation
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Higher Higher Charmonium Charmonium
1)1) SpectrumSpectrum
2)2) Strong decays (main topic)Strong decays (main topic)
3)3) L’oopsL’oops
Ted BarnesPhysics Div. ORNLDept. of Physics, U.Tenn.
GHP2004 Fermilab, 24-26 Oct. 2004
abstracted from T.Barnes, S.Godfrey and E.S.Swanson, in prep.
1. Spectrum
Charmonium (cc)A nice example of a QQ spectrum.
Expt. states (blue) are shown with the usual L classification.
Above 3.73 GeV:Open charm strong decays(DD, DD* …):broader statesexcept 1D
2 22
3.73 GeV
Below 3.73 GeV: Annihilation and EM decays.
, KK* , cc, , ll..):narrow states.
s = 0.5538
b = 0.1422 [GeV2]m
c = 1.4834 [GeV]
= 1.0222 [GeV]
Fitted and predicted cc spectrumCoulomb (OGE) + linear scalar conft. potential
model blue = expt, red = theory.
S*S OGE
L*S OGE – L*S conft, T OGE
cc from LGT
exotic cc-H at 4.4 GeV
cc has returned.
Small L=2 hfs.
A LGT e.g.: X.Liao and T.Manke, hep-lat/0210030 (quenched – no decay loops)Broadly consistent with the cc potential model spectrum. No radiative or strong decay predictions yet.
2. Strong decays (open flavor)
Experimental R summary (2003 PDG)Very interesting open experimental question:Do strong decays use the 3P
0 model decay mechanism
or the Cornell model decay mechanism or … ?
br
vector confinement??? controversial
ee, hence 1 cc states only.
How do open-flavor strong decays happen at the QCD (q-g) level?
“Cornell” decay model:
(1980s cc papers)(cc) (cn)(nc) coupling from qq pair production by linear confining interaction.
Absolute norm of is fixed!
The 3P0 decay model: qq pair production with vacuum quantum numbers.
L I = g
A standard for light hadron decays. It works for D/S in b1 .
The relation to QCD is obscure.
What are the total widths of cc states above 3.73 GeV?
(These are dominated by open-flavor decays.)
< 2.3 MeV
23.6(2.7) MeV
52(10) MeV
43(15) MeV
78(20) MeV
PDG values
X(3872)
Strong Widths: 3P0 Decay Model
1D
3D3
0.5 [MeV]
3D2
-
3D1
43 [MeV]
1D2
-
DD 23.6(2.7) [MeV]
Parameters are = 0.4 (from light meson decays), meson masses and wfns.
X(3872)
E1 Radiative Partial Widths
1D -> 1P
3D3 3P
2 305 [keV]
3D2 3P
2 70 [keV]
3P1
342 [keV]
3D1 3P
2 5 [keV]
3P1
134 [keV]
3P0
443 [keV]
1D2 1P
1 376 [keV]
X(3872)
Strong Widths: 3P0 Decay Model
1F3F
4 8.3 [MeV]
3F3
84 [MeV]
3F2
161 [MeV]
1F3
61 [MeV]
DDDD*D*D*D
sD
s
X(3872)
Strong Widths: 3P0 Decay Model
33S1
74 [MeV]
31S0
80 [MeV]
3S
DDDD*D*D*D
sD
s
X(3872)
52(10) MeV
After restoring this “p3 phase space factor”, the BFs are:
D0D0 : D0D*0 : D*0D*0
partial widths [MeV](3P
0 decay model):
DD = 0.1 DD* = 32.9 D*D* = 33.4 [multiamp. mode]D
sD
s = 7.8
Theor R from the Cornell model.Eichten et al, PRD21, 203 (1980): 4040
DD
DD*
D*D*
4159
4415
famous nodal suppression of a 33S
1 (4040) cc DD
D*D* amplitudes(3P
0 decay model):
1P1 = 0.056
5P1 = 0.251 = 1P
1
5F1
= 0
std. cc and D meson SHO wfn. length scale
Strong Widths: 3P0 Decay Model
2D 23D3
148 [MeV]
23D2
92 [MeV]
23D1
74 [MeV]
21D2
111 [MeV]
DDDD*D*D*D
sD
s
DsD
s*
78(20) [MeV]
Theor R from the Cornell model.Eichten et al, PRD21, 203 (1980): 4040
DD
DD*
D*D*
4159
4415
std. cc SHO wfn. length scale
D*D* amplitudes:(3P
0 decay model):
1P1 = 0.081
5P1 = 0.036 1P
1
5F1 = 0.141
partial widths [MeV](3P
0 decay model):
DD = 16.3 DD* = 0.4 D*D* = 35.3 [multiamp. mode]D
sD
s = 8.0
DsD
s* = 14.1
Strong Widths: 3P0 Decay Model
4S 43S1
78 [MeV]
41S0
61 [MeV]
DDDD*D*D*DD
0*
DD1
DD1’
DD2*
D*D0*
DsD
s
DsD
s*
Ds*D
s*
DsD
s0*
43(15) [MeV]
Theor R from the Cornell model.Eichten et al, PRD21, 203 (1980): 4040
DD
DD*
D*D*
4159
4415
DD1 amplitudes:
(3P0 decay model):
3S1 = 0 !!!
3D1 = + 0.110
partial widths [MeV](3P
0 decay model):
DD = 0.4 DD* = 2.3 D*D* = 15.8 [multiamp.]
New mode calculations:
DD1 = 30.6 [m] MAIN MODE!!!
DD1’ = 1.0 [m]
DD2* = 23.1
D*D0* = 0.0
DsD
s = 1.3
DsD
s* = 2.6
Ds*D
s* = 0.7 [m]
An “industrial application” of the (4415).
Sit “slightly upstream”, at ca. 4435 MeV, and you should have a copious source of D*
s0(2317). (Assuming it is largely cs 3P
0.)
3. L’oops
Future: “Unquenching the quark model”
Virtual meson decay loop effects,qq <-> M
1 M
2 mixing.
DsJ
* states (mixed cs <-> DK …, how large is the mixing?)
Are the states close to |cs> or |DK>, or are both basis states important?
A perennial question: accuracy of the valence approximation in QCD.
Also LGT-relevant (they are usually quenched too).
|DsJ
*+(2317,2457)> = DK molecules?
T.Barnes, F.E.Close and H.J.Lipkin, hep-ph/0305025, PRD68, 054006 (2003).
3. reality
Reminiscent of Weinstein and Isgur’s “KK molecules”.
(loop effects now being evaluated)
S.Godfrey and R.Kokoski,PRD43, 1679 (1991).
Decays of S- and P-wave D Ds B and Bs flavor mesons.
3P0 “flux tube” decay model.
The L=1 0+ and 1+ cs “Ds” mesons are predicted to Have rather large total widths, 140 - 990 MeV. (= broad tounobservably broad).
Charmed meson decays (God91)
How large are decay loop mixing effects?
JP = 1+ (2457 channel)
JP = 0+ (2317 channel)
The 0+ and 1+ channels are predicted to have very largeDK and D*K decay couplings.This supports the picture of strongly mixed
|DsJ
*+(2317,2457)> = |cs> + |(cn)(ns)> states.
Evaluation of mixing in progress. Initial estimates for cc …
L’oops evaluated
[ J/ - M1M
2 - J/
3P0 decay model,
std. params. and SHO wfns.
M1M
2 M [J/] P
M1M
2 [J/]
DD
- 30. MeV 0.027
DD*
- 108. MeV 0.086
D*D*
- 173. MeV 0.123
DsD
s - 17. MeV 0.012
DsD
s*
- 60. MeV 0.041
Ds*D
s*
- 97. MeV 0.060
famous 1 : 4 : 7 ratio DD : DD* : D*D*
Sum = - 485. MeV Pcc
= 65.% VERY LARGE mass shift and large non-cc component!
Can the QM really accommodate such large mass shifts??? Other “cc” states?
1/2 : 2 : 7/2 DsD
s : D
sD
s* : D
s*D
s*
L’oops
[ cc - M1M
2 - cc
3P0 decay model,
std. params. and SHO wfns.
Init.
Sum M P
cc
J/ - 485. MeV 0.65
c - 447. MeV 0.71
2 - 537. MeV 0.43
1
- 511. MeV 0.46
0- 471. MeV
0.53 hc
- 516. MeV 0.46
Aha? The large mass shifts are all similar; the relative shifts are “moderate”.
Continuum components are large; transitions (e.g. E1 radiative) will have to berecalculated, including transitions within the continuum.
Apparently we CAN expect DsJ
-sized (100 MeV) relative mass shifts due to decay
loops in extreme cases. cs system to be considered. Beware quenched LGT!
1) Spectrum
The known states agree well with a cc potential model, except:small multiplet splittings for L.ge.2 imply that the X(3872) isimplausible as a “naive” cc state.
2) Strong decays (main topic)
Some cc states above 3.73 GeV are expected to be rather narrow (in addition to 2- states), notably 3D3 and 3F4.
Of the known states, (4040),(4159) and (4415) all have interesting decay modes: 1st 2, D*D* relative amps, and for(4415) we predict DD1 dominance; also a D*
s0(2317) source.
3) L’oops
Virtual meson decay loops cause LARGE mass shifts and cc <-> M1M2 mixing. These effects are under investigation.