Higher Charmonium

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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

Transcript of Higher Charmonium

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.