recent cleo results on hadron spectroscopy
DESCRIPTION
Recent CLEO results on hadron spectroscopy. Tomasz Skwarnicki Syracuse University. Concentrate on the most recent results (mostly quarkonium spectroscopy). Production of b-quark hadrons. G ¡( 3S ) ~ 24 keV. c. G ¡( 4S ) ~ 24 000 keV. W. q. g. p. p. e +. e +. b. B ( s ) (*). b. - PowerPoint PPT PresentationTRANSCRIPT
Recent CLEO results on hadron spectroscopy
Tomasz SkwarnickiSyracuse University
Concentrate on the most recent results (mostly quarkonium spectroscopy).
Epiphany 2005, Krakow Tomasz Skwarnicki 2
Production of b-quark hadrons
SSS S,5S
s
Other states
b
b b
b
e
e
e
e
Soft g
Hard g
Long distance interactions
Short distance interactions
bb spectroscopy bq, (cq, cc) spectroscopy
W
3S ~ 24 keV
4S ~ 24 000 keV
s
c
q
Epiphany 2005, Krakow Tomasz Skwarnicki 3
• B physics runs ((4S)) at CLEO ended in mid 2001.
1
10
100
fb-1
/year
0.1
30.001
0.01
History of CLEO/CESR
(1S)(3S) (2S)
(3S) (2S)(1S)
BaBar
Belle
• CLEO-c phase 2003 – (2007)
CLEO-c
• Long runs at (5S) (3S), (2S),(1S) in 2001 – 2002.
(5S)
or #
of r
eson
ance
s
Epiphany 2005, Krakow Tomasz Skwarnicki 4
CLEO-III data samples
• CLEO “owns” the field of spectroscopy
• Recently more than 10-fold increase in statistics for the narrow resonances over the previous generation of experiments
• Except for a few systematics limited measurements CLEO is no longer competitive in B physics
(1S)
(3S)
(2S)
(in millions of resonance decays)
(4S)
Continuum below (4S)
(in integrated luminosity fb-1)
• Large increase in statistics for 5S with much improved detector leads to a measurement of Bs production rate
(5S)
Epiphany 2005, Krakow Tomasz Skwarnicki 5
Superconducting CESR-cwiggler magnet (2.1 T)
Wigglers needed for low energy operations to increase radiation damping(to keep the size of the beams small)
e+e- collider
No.Of
rings
Instantaneous peak luminosity cm-2 s-1
Beauty Threshold Region
CESR(-b) 1 1.2 1033
PEP-II 2 9.2 1033
KEK-B 2 13.9 1033
Charm Threshold Region
SPEAR II 1 6 1029
BEPC 1 5 1030
CESR-c1 wiggler (fall 2002)
12 1031
6 wigglers (fall 2003) 5 1031
12 wigglers (fall 2004) projected
6 1031
Up to 3 1032
BEPC-II (2007) 2 1 1033
CESR-cCESR(-b)
CESR (single ring machine) PEP-II (double ring machine)
Epiphany 2005, Krakow Tomasz Skwarnicki 6
CLEO-c data samples
• Proposed CLEO-c program:– 3 / 3 / 1 fb-1 at Ebeam=3770 / 4140 / 3100 MeV for DD / DsDs / J/– Would also like to take some(2S), c data and perform scan of R – Likely to be revised if CESR-c doesn’t reach its projected luminosity soon
• Advantages of threshold production of D(s) mesons:– Fully reconstruct one D(s) meson, then look at the other– No backgrounds (often limiting factor for D studies at B factories and fixed target
experiments)– Measurement of absolute branching fractions
~107 pb-1~6 pb-1We are continuingto run at (3770)
3640 3680 3720 3760 3800 3840
Epiphany 2005, Krakow Tomasz Skwarnicki 7
CLEO-c data samples
• (2S) sample smaller (larger) than that of BES (Crystal Ball) with much better detector
(3770)
• (3770) sample much larger than those of Mark III and BES with much better detector
(2S)
(in millions of resonance decays)
Epiphany 2005, Krakow Tomasz Skwarnicki 8
CLEO EM Calorimeter COIL (1.5T)
Detector Calorimetercrystals
E resolution at E=100 MeV
Number of inner segments (crystals)
Inner radius(cm)
CLEO-III CsI(Tl) 4.8 MeV 7800 100
CUSB-II BGO 4.2 MeV 72 8
Crystal Ball NaI(Tl) 4.8 MeV 672 25
BES-II Sampling 70 MeV
• Essential for photon spectroscopy– ~8000 CsI(Tl) crystals + photo-diodes– First crystal calorimeter in magnetic
field• In operation since 1990 (CLEO II)
Much better efficiencyin hadronic events
Narrower0 width
Epiphany 2005, Krakow Tomasz Skwarnicki 9
CLEO III Tracking• Large drift chamber in 1.5T field (lowered to 1.0T for
CLEO-c)
Stepped endplate toaccommodate newmicro- quadrupoles
Deconstruction of CLEO II DRCLEO III DR
Epiphany 2005, Krakow Tomasz Skwarnicki 10
CLEO-c Inner Wire Chamber • CLEO-III Silicon Vertex Detector deteriorated due to radiation damage
and had to be replaced• “ZD Inner Chamber” commissioned Aug/Sep 2003 • The only new detector component of CLEO-c
6 stereo layers 53 to 105 mm radius
Detector Magnetic field
p /p resolution at p=1 GeV
dE/dXresolution
CLEO-c 1.0T 0.5% 6.0%
BES-II 0.4T 2.4% 8.5%
Mark-III 0.4T 2.1%
Tracking resolution
• Much improved momentum and dE/dX resolution compared to the previous charm-threshold experiments
Epiphany 2005, Krakow Tomasz Skwarnicki 11
CLEO-III RICH• LiF – MWPC (Methane +
TEA) proximity focused RICH
RadiatorsLiF
PhotodetectorsMWPC
(Methane+TEA)
CLEO-c
B physics
Kaon efficiency = 0.80= 0.85= 0.90
First detector operating at charm threshold with excellent particle ID
In operation since 2000
Epiphany 2005, Krakow Tomasz Skwarnicki 12
Measurement of fD
Calculate Missing-Massto separate
signal (MM=m=0)from backgrounds:
Epiphany 2005, Krakow Tomasz Skwarnicki 13
Measurement of fD
D- KL -
D- -
8 events (1 background event expected)
Based on 6 wiggler data: 60 pb-1 (29k tagged events)
B(D- -) = (3.5±1.4±0.6) 10-4
fD- = (202±41±17) MeV
First statistically compelling evidence for this decay. (BES 2.7±1.7 events hep-ph/0400150)Need much larger statistics to constrain the theory (data taking in progress!)The same type of calculations used for fB needed for extraction of Vtd from B0B0 mixing
hep-ex/0411050 Accepted by PRD
Epiphany 2005, Krakow Tomasz Skwarnicki 14
D meson BRs
0.0380±0.0009
0.130±0.008
0.075±0.003
0.092±0.006
0.0141±0.0008
Using double-tag method (Preliminary)
PDG 2004
Future goal: reduce errors to 1-2% for the major modes
No surprises
Epiphany 2005, Krakow Tomasz Skwarnicki 15
Heavy Quarkonia bb
S= 0 1 0 1 0 1 L= 0 1 2
?
cc
n 2S+1 L J
S= 0 1 0 1 0 1 0 1 L= 0 1 2 3
n=1
n=2
n=3
n=4
Hyperfine splitting: 1 2S S
Fine splitting:
1 2 1 2
,L S
S r S r S S
n=1
n=2
Hyperfine splitting
Fine splitting
J 1974
’’ 1974
c 1975
c 1980
c’’ 1982 hc
19861992
2002
1977
’’ 1977
’’’ 1979
b 1983
b’ 1982
2 2002’’’ 1977
’IV 1981
2004
CLEO-III
E835CLEO-c
Belle,BaBar,CLEO
Epiphany 2005, Krakow Tomasz Skwarnicki 16
Fine and Hyperfine Structure
• nS states are special:– Have no fine structure (L=0 thus J=S)– The only states for which hyperfine structure is predicted to be significant– Observed in charmonium:
• M(J/) – M(c)= (116±2) MeV; M(’) – M(c’)= (48±4) MeV
• If long range spin-spin forces are negligible then for L>0:– MS=0 = M(c.o.g.) = J (2J+1) MJ
S=1 / J (2J+1)– M(hc)=(5 M(c2)+3 M(c1) + M(c0)) / 9 = (3525.3±0.1) MeV ???
n, L
c.o.g
L S
Spin-orbit
1 2 1 2r rS S S S
Tensor
J = L - 1
J = L + 1
J = L1 2S S
Spin-spin
J = L
S = 0 S = 1Fine structureHyperfine structure
Epiphany 2005, Krakow Tomasz Skwarnicki 17
Inclusive search for hc
0
’
hc
c
• Require 0 recoil mass to be consistent with the c mass
• Plot 0 recoil mass (should reflect the hc mass)
hc
156 ± 48 events3.3significant
anything
Epiphany 2005, Krakow Tomasz Skwarnicki 18
Exclusive search for hc
0
’
hc
c KsK,2K0,2K24,2
• Reconstruct c in one of the exclusive decay modes
• Then follow the same steps as in the inclusive analysis
hc15.0 ± 4.2 events5significant
c mass sidebandsData MC
Signal sample ’ 0 hc 0 c
Optimize c reconstruction on ’ cc
Epiphany 2005, Krakow Tomasz Skwarnicki 19
Preliminary CLEO results for hc mass
For comparison: hep-ex/040085Preliminary E835 results:
Disapprove E760 evidence for pp hc J ~13 pp c events in the peak~3.3 significance for hc
M(hc) = 3525.8±0.2±0.2 MeV
E835
• Inclusive analysis: M(hc)= (3524.8±0.7) MeV• Exclusive analysis: M(hc)= (3524.4±0.9) MeV• Together:
M(hc)= ( 3524.7 ± 0.6 ± 1.0 ) MeV M(c
cog) - M(hc) = ( 0.6 ±1.2 ) MeV• Consistent with zero• In any case small as expected
• The analysis is still in progress and numbers will change slightly before they are published
Epiphany 2005, Krakow Tomasz Skwarnicki 20
Search for X(3872) in fusion and ISR• Reconstruct exclusive J/, J/ events in CLEO-
III high energy data (15 fb-1)Untagged fusionJPC=0±+,2±+,…
Initial State RadiationJPC=1
_ _
No signal found
hep-ex/0410038Accepted by PRL
Epiphany 2005, Krakow Tomasz Skwarnicki 21
Search for X(3872) in fusion and ISRAssuming B(B± → K± X) ≈ B(B± → K± ψ’) → B(X → π+ π- J/ψ) ≈ 0.02our limits imply:
(2J+1)X(3872)) < 0.65 keV
• ¼ that for χc0 and χc2
• Ackleh &Barnes prediction for 11D2 state: (2J+1)(11D2) keVee(X(3872)) < 0.42 keV• comparable to ψ(3770)• ½ that of ψ(4040)
Epiphany 2005, Krakow Tomasz Skwarnicki 22
Determination of B((nS) )Measure yields on and off the resonance peaks
• Much larger samples than previously available
• Much better detector than previously available (tracking, calorimeter, muon system)
Epiphany 2005, Krakow Tomasz Skwarnicki 23
• Compared to the previous measurements:– Good agreement for (1S)– Substantial disagreement for (2S), (3S)
Determination of B((nS) )CLEO-III
hep-ex/0409027Accepted by PRL
Epiphany 2005, Krakow Tomasz Skwarnicki 24
Determination of tot((nS))
B((nS) ) are important for determination of tot((nS))
and CLEO-III values for B and PDG values for B
• Important change for many comparisons of data (Bx) vs theory (x): Bx=x/tot
Epiphany 2005, Krakow Tomasz Skwarnicki 25
Photon transitions – E1
123
456
7891011
1213,14,15
16,1718
J=210
J=210
BR * tot E1
E M(n3PJ)
• Electric Dipole Transitions
g g gHadrons (…0..)
g g g
123
5,46
(2S)
21 3
65,4
(2S)87 9
65,4
1211,10
1514,13
16,1718
(3S)
22 3
E1 f f iQ iL r Le n n E
g g
cc
bb
Epiphany 2005, Krakow Tomasz Skwarnicki 26
Photon transitions – E1
123
789
J=210
J=210
(2S)
(2S)
cc
bb(3S)
1
1 2
2
3
3 879
hep-ex/0408133 Accepted by PRD
hep-ex/0408133 Accepted by PRL
16,1718
(3S)
18
16,1733S1 13P0
Epiphany 2005, Krakow Tomasz Skwarnicki 27
Comparison to previous measurements - examples(2S) bJ(1P2) (3S) bJ(2P2)
Good agreementon Ei.e.mbJ
Disagreements on B((3S) bJ(2PJ))
Improvedprecision
Epiphany 2005, Krakow Tomasz Skwarnicki 28
Fine splitting of P-states• Tests of relativistic corrections to the mass spectrum
01
12
mmmm
r
r(1P) 0.570.010.01
r(2P) 0.580.010.01
r(1P) 0.4900.0020.003
bb
cc
Nearly equal, against most of theoretical predictions.}
The results favor confining potential of effective scalar type
(=0.8 for pure Coulomb potential)
Epiphany 2005, Krakow Tomasz Skwarnicki 29
Relativistic effects in transition rates• In non-relativistic approximation E1 matrix
elements are spin (J) independent2
E1 E13 3(2 1) (2 1)
( )f f i i JL L
Jr
B in n fE E
(J=2)/(J=1)b(2P): (J=0)/(J=1)
(J=0)/(J=2)
1.000.010.050.760.020.070.760.020.09
(J=2)/(J=1)b(1P): (J=0)/(J=1)
(J=0)/(J=2)
1.010.020.080.820.020.060.810.020.11
(J=2)/(J=1)c(1P): (J=0)/(J=1)
(J=0)/(J=2)
1.500.020.050.860.010.060.590.010.05
Ratio of 3(2 1)( ( 1) )J
JB nS n P
E
Consistent with the NRexpectations
Relativistic effects in J=0are expected to be the largest
Smaller c-quark massand substantial 2S-1D1
mixing}cc
bb
Epiphany 2005, Krakow Tomasz Skwarnicki 30
E1 matrix elements• Large relativistic
corrections (triangles) needed to describe E1 rates in charmonium.
• Corrections small in bottomonium.
• Small matrix element 33S1 13PJ difficult to predict (cancellations)
Date ofpublication 33S1 13PJ
33S1 23PJ
S.Godfrey
23S1 13PJ
-+
McC
lary
83
Gro
tch
84 23S1 13PJ
23S1 13PJ
33S1 23PJ
33S1 13P0
<1P 0|r
|3S>
“Spin averaged” matrix elements
bb
bb
cc
Epiphany 2005, Krakow Tomasz Skwarnicki 31
Photon transitions – M1
4
A way to reach singlet states
Crystal Ball claimed observation of all M1 transitions in charmonium ~20 years ago (Direct: “1”, “2”, Hindered: “4”)
1
2
365
• Magnetic Dipole Transitions
3
g g
2
4
(2S)
(2S)
4
2
(3S)
5
6
3
3
2 2
M3
1 2
DIRECT
1
tiny
HINDERED
l
0
arge
f i
f i
f i
i f
i f
Q
Q
n n
n
L L
n L n L
n L n
E
E
n
L
mE
en n
cc
bb
Epiphany 2005, Krakow Tomasz Skwarnicki 32
Search for b(11S0)
• No signal found for this or any other M1 transition in the Upsilon system
Hindered M1
E1
E1
E123PJ13S1 M1
33S111S0
M123S111S0(2S)
(3S)
cc
bb
4
6
(4)
(6)
Epiphany 2005, Krakow Tomasz Skwarnicki 33
M1 matrix elements
• Even recent calculations only marginally consistent with our upper limit on 33S1 11S0
13S1 11S0
23S1 11S0
23S1 11S0
33S1 21S0
33S1 11S0
allowed range
Lahd
e 03
Ebe
rt 0
3
Date ofpublication
Epiphany 2005, Krakow Tomasz Skwarnicki 34
Inclusive (2S) X J/(1S), J/(1S) +-
cut cutcut cut
MCLog
scal
e !
• Large statistics, good agreement with MC precision measurement of B((2S) X J/(1S))
Epiphany 2005, Krakow Tomasz Skwarnicki 35
Exclusive (2S) X J/(1S), J/(1S) +-
Epiphany 2005, Krakow Tomasz Skwarnicki 36
Exclusive (2S) X J/(1S), J/(1S) +-
Epiphany 2005, Krakow Tomasz Skwarnicki 37
(2S) X J/(1S), J/(1S) +-
• Preliminary results presented at QWG workshop Oct 2004
• Improved results are being prepared for publication.
Epiphany 2005, Krakow Tomasz Skwarnicki 38
Exclusive hadronic (2s) decays
Log scale!
• A lot of theoretical complications e.g.:
– Interference with continuum– s and relativistic
corrections• Happy with agreements
within a factor of ~2
Epiphany 2005, Krakow Tomasz Skwarnicki 39
Exclusive hadronic (2s) decays
• (2s) Dalitz plot distinctively different than continuum or J/(1S)
BESJ/
CLEO(2S)
Epiphany 2005, Krakow Tomasz Skwarnicki 40
Exclusive hadronic (2s) decays
Linear scale
Epiphany 2005, Krakow Tomasz Skwarnicki 41
Continuum production of PV at 3.67 GeVhep-ex/0407028
Epiphany 2005, Krakow Tomasz Skwarnicki 42Summary• First statistically compelling measurement of fD-
• Observe highly significant (2S)0hc,hc c signal with the hc mass consistent with the c.o.g. of the cJ states
• Non-observation of X(3872) and ee X(3872). • Precision measurements of B((nS) ). The results for
(2S),(3S) significantly different from the PDG values, impacting estimates of the total widths of these states.
• Precision measurements of photon transitions from (2S),(2S),(3S). More sensitive tests of relativistic corrections in the potential model calculations.
• Precision measurements of inclusive and exclusive transition rates for (2S) X J/(1S). Some significantly different from the previous measurements.
• Many new insights into B((2S)X)/B(J/(1S) X) for 2- and multi-body exclusive final states.
• First measurements of continuum productions of 2-body pseudo scalar-vector final states at 3.67 GeV. Ratios of cross-sections in rough agreement with SU(3) except for K*0K0