How BaBar can decide

1
How BaBar can decide what charmonium-like
states 4260, 4360. really are
The accidental discovery of a new spectroscopy?
Work by FC with Clark Downum (in PRL) and Chris
Thomas (preliminary)
2
4 to 4.5 GeV region
Gluonic charmonium (hybrid) predicted couples to
DD1 and DD0
Strong attractive forces between D D1 also
between DD1 and DD0
And enigmatic state(s) observed in expt
How BaBar can resolve the dynamics !
2
3
1(3872)
DD
DD1
1--(4260)
DD1
JPC?(4430)
1- - (4360) psiprime pipi
I1 !?
DD1
17
3
4
1(3872)
DD
DD1
1--(4260)
DD1
JPC?(4430)
1- - (4360) psiprime pipi
I1 !?
DD1
all are S wave in s-channel!
17
4
5
Why are nuclear binding energies \sim O(1) MeV
per nucleon ?
5
6
Why are nuclear binding energies \sim O(1) MeV
per nucleon ?
Pi exchange is in P-wave penalty
6
7
Why are nuclear binding energies \sim O(1) MeV
per nucleon ?
Pi exchange is in P-wave penalty
What if Pi exchange is in S-wave no penalty
gt binding energies \sim O(100) MeV per hadron
7
8
Why are nuclear binding energies \sim O(1) MeV
per nucleon ?
Pi exchange is in P-wave penalty
What if Pi exchange is in S-wave no penalty
gt binding energies \sim O(100) MeV per hadron
Can happen for D1 gt D pi in S wave
8
9
Why are nuclear binding energies \sim O(1) MeV
per nucleon ?
Pi exchange is in P-wave penalty
What if Pi exchange is in S-wave no penalty
gt binding energies \sim O(100) MeV per hadron
Can happen for D1 gt D pi in S wave

• D1D deep bound molecules
• And in S-wave 1- -
• Examples 4260 4360 ..

9
10
1(3872)
DD
DD1
1--(4260)
DD1
JPC?(4430)
1- - (4360) psiprime pipi
I1 !?
DD1
all are S wave in s-channel!
17
11
gluonic degrees-of-freedom


R
Costs about 1 to 1.5GeV energy to excite
phonon pi/R Hybrid qq _at_ 2GeV Hybrid cc _at_
4-4.5GeV
Barnes FC Swanson 93
11
12






Predicted 1- Hybrid masses (with spin splittings)





charmonium

13






Predicted 1- Hybrid masses (with spin splittings)





charmonium
Near D(L0)D(L1) thresholds DD0 DD1
DD0DD1 and strongly coupled to these
channels ..how distinguish hybrid from DD1 etc
molecules?

14






Predicted 1- Hybrid masses (with spin splittings)





Spin hyperfine splittings 1- - (4.25)
Y(4260?) 1- (4.1) HQLGT 0- (3.95)
X(3940?)
Barnes FC 82 Chanowitz Sharpe
ee- feebly coupled
ee- \to \psi X?

14
15
ee- to X
Novel states in
???
0-1-
15
16
ee- \to psi pi pi BaBar sees unusual vector cc
\Gamma(ee) 5-80eV Compare \sim 1 keV !!
psi pipi violate OZI
But width 90MeV typical hadron !
psi
D
Y(4260)
D_1
uu pi pi
16
17
Beyond Spectroscopy
To do more need dynamics Production decays
selection rules
Lattice hints about dynamics Hybrids and DD1
decays
17
35/18
18
What properties
18
19
What properties
Lattice S-wave decays now calculated Michael
McNeile
confirms Flux Tube for hybridconventional
Michael McNeile 06 FC Burns 06
Exactly WHAT is Lattice revealing about
dynamics What significance if ratio \sim 2?
18
20
qq create in S1


2

qq create in S0
0
19
21
J S L
Factorisation of S and L
qq created in S1
Factorisation and S1 creation is powerful result
if generally true.
Determine nature of Y(4260) by DD_1 pattern
20
22
SL Factorisation and S1 selection rules for
psi(cc) \to DD_1

Also applies to KK_1 decays of ss vectors e.g.
ISR around 2.2 GeV
21
23
4260 decays. using strong selection rules to
distinguish candidates Conventional
charmonium Hybrid charmonium Tetraquark cscs
Charm molecule DD1 or DD1
22
24
flux-tube breaking and hybrid decays


Isgur Paton 92 light exotics
FC Page 95 all
Break tube SP states yes SS suppressed
Look for DD_1 and DD_0 near threshold

Absence of DD DD DsDs
24
25
Y(4260) D_s and D_s channels




No DsDs resonance

eliminates tetraquark cscs
25
26
Y(4260) D and D channels




No DD DD or DD resonance
25
27
All consistent with predictions for hybrid
charmonium FCPage 1995
Search DD_1 and DD_0 in DD\pi\pi
If NOT hybrid cc then why not/where is it ?!
27
28
The large psi pi pi hint of large D()D1
ee- psi(hybrid)
D()D_1
S-wave, relative mom \sim 0 DD_1 interchange
constituents to make psi pipi strongly
psi
D
D_1
uu pi pi
28
29
The large psi pi pi hint of large D()D1
ee- psi(hybrid)
D()D_1
S-wave, relative mom \sim 0 DD_1 interchange
constituents to make psi pipi strongly
psi
D
D_1
uu pi pi
Problem Heavy cc preserve their spin.
Psi has cc with S1 Hybrid
has cc with S0 (h1c eta or etac omega ?)
Problem and other states 43604430
28
30
Hybrid affected by thresholds Attractive force
from pi exchange 4260 a result of D1D (!!)
threshold look for ee- \to DDbar 3pi
And what about 4360 in psiprime pipi and 4430 in
psiprime pi ..????
29
31
The Answer A new spectroscopy?

• At least..something unexpected!
• 1(3872) DD via \pi exchange in p-wave
• 1 (4260 etc) D1D via \pi exchange

30
32
The Answer A new spectroscopy?

• At least..something unexpected!
• 1(3872) DD via \pi exchange in p-wave
• 1 (4260 etc) D1D via \pi exchange
• in s-wave!

31
33
N N pi deuteron O(1 MeV)
D to D pi (P wave) O(q2) DD to DD binding O(1
MeV) X(3872)
32
34
N N pi deuteron O(1 MeV)
D to D pi (P wave) O(q2) DD to DD binding O(1
MeV) X(3872)
1(3872)
DD
32
35
N N pi deuteron O(1 MeV)
D to D pi (P wave) O(q2) DD to DD binding O(1
MeV) X(3872)
D1 to D pi (S wave) O(mA-mB)2 D1 D binding
O(100 MeV)
M DD1(4440) - O(100MeV) 4260
4360 ??
33
36
Look at I1 D1D 1-- S wave pi exchange Find
it does NOT bind
34
37
I1 feeble binding if any Z(4430) Liu et al PRD77
034003
35
38
I1 feeble binding if any Z(4430) Liu et al PRD77
034003
I0 strong binding
36
39
Binding Energy variational wfns
37
Radial excitation bound also??
Ground state B.E can be 100-200 MeV !!
40
Psi(1S)pipi (4260)
Psi(2S)pipi (4360) and (?) 4600
38
41
DD1 spectroscopy
4430 I1
DD1 threshold
Potential is similar to Coulomb
4360
2S
1P
4350
4260
1S
39
42
Vector DD1 spectroscopy
4430 I1
DD1 threshold
4360
2S
cc psi
D
D_1
uu pi pi
4260
1S
40
43
Vector DD1 spectroscopy
4430 I1
DD1 threshold
4360
2S
cc psi
D
(1S 2S)
1S 2S
D_1
uu pi pi
4260
1S
41
44
Vector DD1 spectroscopy
4430 I1
DD1 threshold
4360
2S
Psi(2S) pi pi
4260
1S
Psi(1S) pi pi
42
45
Vector DD1 spectroscopy
4430 I1
DD1 threshold
4360
2S
Psi(2S) pi pi
4260
1S
Psi(1S) pi pi
DD pi pi pi
43
46
Phys Rev Letters (in press)
The immediate test is 4260 decay to
Then look for other exotica. Also in Bottomonium
and strangeonium
44
47
Since PRL (n.b. preliminary - not yet guaranteed)
Sensitivity to D1 and D0 widths for pointlike
mesons (value of h) Effect of finite D meson
size (h function of momentum) Effect of extended
pion (Lambda)
And discovery of DD1/DD0 molecules too
including exotic J(PC)1(-)
45
48
D and pi pointlike





h1 3800
h2 width of D_1 to D \pi
h0.9 4050
Data h \sim 0.7 0.8
h0.8 4250
h0.7 4350




49
Pion size (Lambda)


Bad news
Reduces BE Extended pion provides smaller
force BE tends to zero.


50
Pion size (Lambda)


Bad news
Reduces BE Extended pion provides smaller
force BE tends to zero.
Good news

• Finite D size
• h(q) gt h(0) increases to gt 1
• Scale of BE increases

51
51
52

52
53
4260

4360
Threshold 4440
52
54
Surprisingly robust ! Can force-fit because so
sensitive so not a real pre-diction Need
direct unambiguous tests decay channels

53
55
Surprisingly robust ! Can force-fit because so
sensitive so not a real pre-diction Need
direct unambiguous tests decay channels
Look for D Dbar pi pi pi (for D1 D
deep bound molecules) Look for D Dbar pi pi (not
DD) for DD1/DD0 molecules and threshold
accidents
53
56
Surprisingly robust ! Can force-fit because so
sensitive so not a real pre-diction Need
direct unambiguous tests decay channels
Look for D Dbar pi pi pi (for D1 D
deep bound molecules) Look for D Dbar pi pi (not
DD) for DD1/DD0 molecules and threshold
accidents
DD1/DD0 molecules also and exotic 1- Look in
ee- \to (D Dbar pi pi) gamma
54
57
DD1 threshold
4430
4360
D D1 threshold
4290
4260
55
58
Option 1 4360 spurious 4260 hybrid or cc
attracted to DD1 threshold
DD1 threshold
4430
spurious
4360
D D1 threshold
4290
D D1 b state or hybrid at threshold
4260
D D pi pi
( DD1 or DD0 not DD )
560
59
Option 2 4360 and 4260 DD1 molecules
DD1 threshold
4430
2S psiprime pi pi
4360
D D1 threshold
4290
1S psi pi pi
4260
D D pi pi pi
57
60
4260 in psi pi pi _at_ 90 MeV width
MUST be due to some charm meson pair Finding
which gt reveals dynamics in the 4 to 4.5 GeV
region where hybrids also predicted. DDpipi (not
DD) and DDpipipi are where the answers are to
be found
61
The antidote to Angels and Demons available
from Amazon et al
62
Intriguing resonant signal at 2175
ee- KK_1
2175 m(phi) 4265 m(psi) !!??
phi
pi pi
Study KK1 pattern
41/12
63
Psi pipi (4260)
Psi(1S)pipi (4260)
BaBar and Belle and CLEO