Stephen Lars OlsenSeoul National University
February 10, 2014
A New Spectroscopy of Hadrons
High-1Gangwando
Through a theorist‘s mind
Visions of hadrons
What is seen by an experimenter
multiquark states from diquarks & diantiquarks
magentaanti-triplet
_ 3
_ 3
_ 3
yellowanti-triplet
cyananti-triplet
d
d d
d
d
u
u
u
u
u
uss s s s s
us
d
du
s
d
H-dibaryon
(anti-green) (anti-blue) (anti-red)
red-blue diquark green-red diquark blue-green diquark
uu
d
ds
Pentaquark
_
uccd
tetraquark meson_ _
magenta-cyan-yellowcolor singlet 6-q state
magenta-cyan-yellowcolor singlet 5-q state
green-magentacolor singlet 4-q state
(anti-green)
“exotic” hadrons that particle theorists love
multiquark states from “molecules”
H-dibaryon
uu
d
ds
Pentaquark_
c
uc
d
p,s,r,w
_
_
D
D*
p,s,w
us
d
us
d
s,w
tetraquark meson
L
L
N
K
baryonium
uu
d
uu
d
p,s,w
p
p_ _
__
_
“exotic” hadrons that nuclear theorists love
Non-qq mesons or non-qqq baryonspredicted by `QCD-motivated’ models
u cuc c c
u du
sd_
___
u d
usds
_u c
uc
__
_p
D0
D*0_
pentaquarksglueballs H-dibaryon
diquark-diantiquarks hybridsmolecules
_
Where are they??
non-qq & non-qqq color-singlet combinations_
The XYZ quarkonium-like mesons
Charmonium spectrum
Any meson that decaysto a c and c quark shouldfit in one of the (gray)unassigned states.
XYZ charmoniumlike mesons
1+(-)
0-+
0++
1++
Zc(3900)+ 3899 ± 6 46 ± 22 1+(-) Y(4260)p-(p+J/y)
0-+
0+(+)/1—(+)
0+(+)/1—(+)
cc assignments for the XYZ mesons?_
no unassigned levels forthe 1- - Y(4260) & Y(4360)
the X(3940) & X(4160) asthe hc(3S) & hc(4S) wouldimply huge hyperfinesplittings for n=3&4
the Y(3915) mass andG(YwJ/y) are toohigh for the cc0(2P).Also, no sign of YDD
the (4) charged Zsmust have a minimalquark content of ccud_
the X(3872) is a longcomplex story
_
_
the Y(4260)
s(e+e- hadrons)
Ecm (GeV)BaBar PRD86, 051102
M(p+p-J/y) (GeV)
found by BaBar in e+e- gISRp+p-J/y
Y(4260) p+p-J/y confirmed by BelleBelle PRL99, 182004
Y(4260) peak in s (p+p-J/y)occurs at a dip in s(D(*)D(*))
G(p+p-J/y) is large,10~100 × charmonium
e+e- gISRp+p-J/y
No sign of Y(4260) D(*)D(*)
M(p+p-J/y) (GeV)
BESII PRL88, 101802
Ecm (GeV)
X. H. Mo et al., PLB 640, 182
e+e- hadrons
Is there a b-quark version of Y(4260)?
BB
BB*
B*B*
e+e- hadrons
Ecm (GeV)
e+ e- h
adro
ns
e+ e- p
+ p- J/y
e+ e- p
+ p- ϒ(1
S)
?p+p-ϒ(1S)
e+e- p+p-J/y
_
Is there any anomaly in(4S,5S) p+p- (1S) ?
“bottomonium” bb mesons
2MB = 10358.7 MeVϒ(4S
)
p+p-
G(4S)p+p-(1S) G”(5S)”p+p-(1S)
2S3S
4S
(4S) (1S) p+p-
477 fb-1
52±
10 e
vts
Belle: PRD 75 071103
Signal
23.6 fb-1Belle: PRL 100 112001
325±
20 e
vts
parent N(p+p-(1S)) G(Y4Spp1S) Gtheory
(4S) 52±10 1.75 ± 0.35 keV
1.47±0.03 keV
“(5S)” 325±20 590 ± 110 keV <1.5 keV
Lum ~1/20th
σ ~1/5th Signal ~×6
“5S”4S
3S2S
“(5S)” p+p- (1S) ?
Υ(1S)π+π-
Υ(2S)π+π-
Υ(3S)π+π-
M2(π+π-)
M2(ϒ
π±)
M2(ϒ
π±)
M2(ϒ
π±)
π+π-
π+π-
“(5S)” p+p- (1S) ?
M(ϒ(1S)π±)
Υ(1S)π+π-
Υ(2S)π+π-
M2(ϒ
π±)
π+π-
π+π-
Υ(3S)π+π-
M(ϒ(3S)π±)
“(5S)” p-Zb1,2+
p+ (1,2,3S)
(3S)
(2S)
(1S)
M((nS)π+)max
p+
10,6
10 M
eV10
,660
MeV
Belle PRL 108, 122001 (2012)121.4 fb-1
JP of the Zb states
JP of the Zb states
19
Belle PRELIMINARY
Zb(10610)M=106082 MeV
G=18.42.4 MeV
Zb(10650)
M=106532 MeV
G=11.52.2 MeV
Belle PRL 108, 122001
Summary of parameter measurements
mB+
mB*
2mB*
March 2012bd
bd
B
B*
B-B* & B*-B* molecules??B
B*
b
b
_
B-B* “molecule”
B*
B*
b
b
_
B*-B* “molecule”_ _
_ _
Zb(106010)± Zb(106050)±
MZb(106010) –(MB+MB*) = + 3.6 ± 1.8 MeVMZb(106010) –2MB* = + 3.1 ± 1.8 MeV
Slightly unbound threshold resonances??
M=10608.11.7 MeVG=15.52.4 MeV
M=10653.31.5 MeVG=14.02.8 MeV
PDG: MB + MB* = 10604.50.6 MeV MB* + MB* = 10650.2 1.0 MeV
Belle:
_ _
Zb(10610)BB* & Zb(10650)B*B*_ _
Zb(106010)± Zb(106050)±
M(B*B*)_
M(BB*)_
“(5S)” p-(BB*)+_
“(5S)” p-(B*B*)+_
Bf(Zb(10610)BB*
Bf(Zb(10610)p+(bb)
_
_ =6.1±0.4 Bf(Zb(10610)B*B*
Bf(Zb(10610)p+(bb)
_
_=2.8±0.4
Belle arXiv:1209.6450
Are there c-quark versions of Zb’s
Is there a b-quark equivalent?
Y(4260) discovered
Yes, & it decays to Zb states
Are there c-quark versions of Zb’s?
???
run BEPCII/BESIII as a Y(4260) factory
Belle PRL99, 182004
BESIII: arXiv:1303.5949 s(e+e- p+p-J/y) = (62.91.93.7) pb
e+e- gISRp+p-J/y
TypicalJ/y +-e+e- p+p-J/y
@Ecm=4260 MeV
Y4260
J/y p+
p-
e+ e+
Y(4260)p-Zc(3900)+ p+J/y
Mass = (3899.0±3.6±4.9) MeV
Width = (46±10±20) MeV
Fraction = (21.5±3.3±7.5)%
BESIII: PRL 110, 252001
Significance >8s
p+
p-
26
Zc(3900) confirmed by Belle
Mass = (3894.5 ± 6.6 ± 4.5) MeVWidth = (63 ± 24 ± 26) MeVFraction = (29.0 ± 8.9)% (stat. err.
only)
Belle: PRL 110, 252002
p-
Mass = (3883.9 ±1.5 ±4.2) MeV
Width = (24.8 ±3.3 ±11.0) MeV DD*/p+p-J/y = 6.2 ± 1.1 ± 2.7
Y(4260)Zc DD*
Y(4260)p-Zc(3900)+
DD*_D0D*+
D+D*0_
_
_
BESIII PRL 112, 022001 (last month)
D*+
D0
_
Significance >18s
_
JP of the Zc(3900)?
e+ e-
p-
Zc
JPC=??
JPC=0-
initial state:
€
J;Jz = 1;±1 P = −1
final state: p Zc
0- 0+ forbidden by Parity ---
0- 0-
0- 1+ flat
0- 1-
€
L;Lz S;Sz
€
1;±1 0;0
€
0;0 1;±1
€
1;±1 1;0 − 1;0 1;±1€
dNd | cosθ |
€
∝ sin2 θ
€
∝1+ cos2 θ
JP=1-
JP=1+
JP=0-
The data clearlyestablish JP=1+
1;±1
BESIII data
q
Are there others?
Study Y(4260)p+p- hc decays
p+p-
BESIII PRL 111, 242001 (2 months ago)
sharp M(phc) peak but not near ~3900 MeV
M(p±hc)
ghc16 channels
g
hadrons
Y(4260)p+Zc(4020)-
Mass = (4022.9 ±0.8 ±2.7) MeV
Width = (7.9 ±2.7 ±2.6) MeV
fraction = 0.18 ± 0.07
no significant signal for Zc(3900)±p±hc
BESIII PRL 111, 242001
M(p±hc)
Fit results:
= 4017.3 ±0.3 MeV5.6 ± 2.8 MeV above D*0D*- thresh.
Zc(4020)
p+
p-
g
p-hc
hadrons
Does the Zc(4020)DD*? … D*D*?_ _
Zc(4020)DD*?_
D0D*+
D+D*0
_
_
4023
MeV
No sign of Zc(4020)DD*_
BESIII PRL 112, 022001
4023
MeV
BESIII arXiv:1308.2760
Mass = (4026.3 ± 2.6 ± 3.7) MeV
Width = (24.8 5 ± 5.6 ± 7.7) MeV
Fit results:
Something there (~10s!), but …
… higher mass (~1.5s) and width (~1.5s)than Zc(4020)phc signal
Zc(4020)D*D*?_
M(D*D*)
_
Zb & Zc mesons --“smoking guns” for non-qq mesons--
ubd
b decay to (nS) (J/y) must contain bb (cc) pair
electrically charged must contain ud pair
_
_
_
bb
b b
B0
B*+
dd
B0-B*+ ? ? Mixture?
ucd
c
Zb Zc
_
molecules?
€
12 (D*D * + D *D*)
€
12 (D*D * − D *D*)
€
12 (DD * + D *D)
€
12 (DD * − D *D)
€
12 (B*B * + B *B*)
€
12 (B*B * − B *B*)
€
12 (BB * + B *B)
€
12 (BB * − B *B)
CMS search for b-sector version of X(3872)
CMS: PLB 727 (2013) 57
€
pp → π+π
−Υ(1S ) + anything
(MB + MB*)-MU(1S)= 1144 MeV >> mw
(MD0 + MD*0)-My(1S)= 776 MeV < mw€
R = σ ( pp → X b →π +π −Υ(1S ))σ ( pp → Υ(2S )→π +π −Υ(1S ))
Relevant channel is ispin-conserving Xbw U(1S)
Y(4260) gX(3872)?
is this from Y(4260) decays?X(
3872
)X(
3872
)
X(38
72)
BESIII arXiv:1310.4101
Y(4260) gX(3872)? …cont’d
BESIII arXiv:1310.4101
X(3872)
Consistent with originating from the Y(4260)
All cm energies combined: 6.3s ~20 evt signal
Summary
QCD-motivated spectroscopies most favored by theorists do not seem to exist
- evidence for Pentaquarks has disappeared
- H-dibaryon with mass near 2mL is excluded at stringent levels
Numerous non-qq mesons not specific to QCD have been found
- Baryonium in J/ygpp at BESII and BESIII ??
- XYZ mesons containing cc and bb pairs
The JPC=1- - Y(4260) and “(5S)” have no compelling interpretation
- huge couplings to p+p-J/y (p+p- (nS)) not predicted in any model!!
- strong sources of charged Zc (Zb) states with M near mD(*)+mD* (mB(*)+mB*)
- evidence for a strong Y(4260)gX(3872) transition
_
_
_ _
Y(4360)
Y(4660)
Y(4260)
Y(4008)
X(3872)
X(4160)
Y(3915)
Z(4430
)
Z 1(4050
)
Z 2(4250
)
Zc(3900)
Y(4140
)
Z b(1061
0)
Z b(1065
0)
Y(4274)
X(3940)
X(4250)
X(4630
)
Lots of pieces
Are they all from the same puzzle?
Back-up slides
Event in the Belle Detector
The “XYZ” mesons
Zb1(10610) 10,607±2 18±2 1- p±ϒ(1,2,3S)/hb(1,2S); BB* `ϒ(5S)’p±Zb1
Zb2(10650) 10,653±2 12±2 1- p±ϒ(1,2,3S)/hb(1,2S);B*B* `ϒ(5S)’p±Zb2
43
“Old” hadron spectrosopy1964 The constituent quark-parton model was proposed independently by Gell-Mann and Zweig. Three fundamental building blocks 1960’s (p,n,l) Þ 1970’s (u,d,s)
mesons are bound states of a of quark and anti-quark:
baryons are bound state of 3 quarks:
€
p + =ud π 0 = 12 (uu − dd ) π - = du
K + = us K 0 = ds K 0 = sd K − = su
€
p = uud n = udd Λ = uds
p = u u d n = u d d Λ = u d s
€
p− =du
€
L =uds
QPM Superseded by QCD in the 1970s:observed particles are color singlets
Λ= (uds) )( ud=-p
Mesons are color-anticolor pairsBaryons are red-blue-green triplets
3 primary colors white whitecolor + complementary color
blue-yellowgreen-magenta
red-cyan
QCD “diquarks” ?
s
ud
=s
ud
u
_ 3
antisymmetric anti 3-plet
du ud-
sd ds- su us-
dd uu
ss
du ud+
sd ds+ su us+
symmetric 6-tet
6
3 3 = 3 6_
Through a theorist‘s mind
Visions of hadrons
What is seen by an experimenter
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