Post on 04-Jan-2016
Paola Gianotti - LNF
Goals and achievements in meson spectroscopy:LEAR and FermiLab activities
Overview of the GSI Future Project The Antiproton Physics Program
Charmonium spectroscopyHybrids and glueballsMedium modification of mesonsHypernuclei
The PANDA detector concept Conclusions
From LEAR to HESR:From LEAR to HESR:
past, present and future of mesonpast, present and future of meson
spectroscopy with antiprotons spectroscopy with antiprotons
Paola Gianotti - LNF
Goals and achievements in meson spectroscopyGoals and achievements in meson spectroscopy
QCD is the accepted theory of strong interaction even if calculating the properties of mesons from the QCD Lagrangian is very difficult phenomenological models are used instead
All these models predict in addition to
conventional states exotic states with
explicit glue content
Some of these exotic states have been finaly identified even if our understanding of ordinary mesons is not exhaustive
Paola Gianotti - LNF
Different experimental techniques are used to disentangle these states:
• Studies of different final states;
• Selection of special working conditions or final states to filter
initial state quantum numbers;
• Production mechanisms ( collisions, pp annihilation,
peripheral or central production, etc).
Goals and achievements in meson spectroscopyGoals and achievements in meson spectroscopy
Meson spectrum consists of an increasingly large number of broad overlapping states crowed in the mass region around 1÷2 GeV.
Paola Gianotti - LNF
The LEAR The LEAR inheritanceinheritance
Three glueball candidates: f0(1500), f0(1370), f0(1710) 0++
(1440) 0+
Two hybrids candidates: 1(1400), 1(1600) 1+
Beam intensity 104 ÷ 106 p/s
Beam momentum
100÷2000 MeV/c
Δp/p 10-3
Machine vacuum 10-11÷ 10-12 Torr
circumference 78.54 m
Paola Gianotti - LNF
OBELIXOBELIX
A.Bertin et al.,Physics Letters B385, (1996), 493. A.Bertin et al.,Physics Letters B400, (1997), 226.
A.Bertin et al.,Physics Letters B361, (1995), 187.
F.Nichitiu et al.,Physics Letters B545, (2002), 261.
The LEAR inheritanceThe LEAR inheritance
Crystal BarrelCrystal Barrel
Paola Gianotti - LNF
The Fermilab activityThe Fermilab activity
0
Many results come from E760-E835 experiments at Fermilab Antiproton Accumulator
8·1011 p per stackaccumulation rate 4 · 1010 p/hp accumulated at 8.9 GeV/c anddecelerated decreasing dipole current “fine scan” using stochastic cooling
Initial beam intensity 1012 p Gas jet target density 1012 ÷1014 atoms/cm3
to keep luminosity constant 2·1031 cm-2sec-1
Momentum spread p/p 10-4→ (√s) 200 KeV
8·1011 p per stackaccumulation rate 4 · 1010 p/hp accumulated at 8.9 GeV/c anddecelerated decreasing dipole current “fine scan” using stochastic cooling
Initial beam intensity 1012 p Gas jet target density 1012 ÷1014 atoms/cm3
to keep luminosity constant 2·1031 cm-2sec-1
Momentum spread p/p 10-4→ (√s) 200 KeV
Paola Gianotti - LNF
SIS 100/300
HESR
SuperFRS
NESR
CR
p Target
GSI Future FacilityGSI Future Facility
UNILAC SIS
FRS
ESR
Primary Beams
• 238U28+ 1.5 GeV/u; 1012/s ions/pulse • 30 GeV protons; 2.5x1013/s
• 238U73+ up to 25 (- 35) GeV/u; 1010/s
Storage and Cooler Rings
• Radioactive beams• e – A collider
• 1011 stored and cooled p0.8 - 14.5 GeV
• Cooled beams• Rapidly cycling superconducting magnets
Key Technical Features
• Broad range of radioactive beams up to 1.5 - 2 GeV/u• Antiprotons 3 (0) - 30 GeV
Secondary Beams• From protons to uranium- In future also atiprotons
• From 1MeV/u to 2 GeV/u- In future up to 30 GeV/u
• 109 to 1011 particles/cycle - In future 1012 particles/cycle• 0.1Hz to 1Hz repetition rate
- In future up to 3 Hz
• From protons to uranium- In future also atiprotons
• From 1MeV/u to 2 GeV/u- In future up to 30 GeV/u
• 109 to 1011 particles/cycle - In future 1012 particles/cycle• 0.1Hz to 1Hz repetition rate
- In future up to 3 Hz
Paola Gianotti - LNF
HESR - High Energy Storage RingHESR - High Energy Storage Ring
High luminosity mode High resolution mode
• p/p ~ 10-5 (electron cooling)• Lumin. = 1031 cm-2 s-1
• Lumin. = 2 x 1032 cm-2 s-1 • p/p ~ 10-4 (stochastic cooling)
• Production rate 2x107/sec
• Pbeam = 1 - 15 GeV/c
• Nstored = 5x1010 p
• Internal Target
Paola Gianotti - LNF
Charmonium spectroscopyCharmonium spectroscopy
Charmonium spectrumis becoming more clear…
• 5 new measurements of c mass
Paola Gianotti - LNF
Even on the ground state on the simplest parameters thereare consistency problems…
Five new measurements published 2002-2003,four by e+e- experiments
Charmonium spectroscopyCharmonium spectroscopy
Paola Gianotti - LNF
Charmonium spectrumis becaming more clear…
• ’c unambiguously seen
Charmonium spectroscopyCharmonium spectroscopy
• 5 new measurements of c mass
Paola Gianotti - LNF
3580 3600 3620 3640 3660 3680
CBALL 86(2S)→X
’c
3637.7±4.4 MeV
BELLE 02B→K (KSK+-)
BELLE 03e+e-→J/ X
CLEO 03→KSK+-
BABAR 03→KSK+-
Mass (MeV)
New measurementsof mass are consistent!
tot = (19 ± 10) MeV
Charmonium spectroscopyCharmonium spectroscopy
Paola Gianotti - LNF
Charmonium spectrumis becaming more clear…
Open problems…
• 5 new measurements of c mass
• ’c unambiguously seen
• h1c not confirmed
•States above DDthr. are not well established
Charmonium spectroscopyCharmonium spectroscopy
Paola Gianotti - LNF
MassDecay
channelsstudied
Total BR seen (%)Decay
ChannelsWith error <30%
c 2979.6±1.2 21 60.3 3
’c 3654.0±6.0 4 ~ 0 0
J/ 3096.92±.01 135 44.2 83
’ 3686.09±.03 62 77.1 29
c0 3415.2±0.3 17 12.3 10
c1 3510.59±.10 13 33.6 6
c2 3556.26±.11 19 26.3 10
hc 2 ? 0
(3770) 3770.0±2.4 2 ~ 0 1
(3836) 3836±13 1 ~ 0 0
X(3872) 3872.0±0.6 3 ~ 0 0
(4040) 4040±10 6 ~ 0 1
(4160) 4159±20 1 ~ 0 0
(4415) 4415±6 2 ~ 0 0
Paola Gianotti - LNF
3500 3520 MeV3510C
Ball
ev./
2 M
eV
100
ECM
CBallE835
1000
E 8
35
ev./
pb
c1
Charmonium PhysicsCharmonium Physics
e+e- → ’→
→ e+e-→ J/
● e+e- interactions:
- Only 1-- states are formed- Other states only by secondary decays (moderate mass resolution)
- All states directly formed (very good mass resolution)
→ J/→ e+e-
p p→ 1,2
● pp reactions:
Br(e+e- → ) ·Br( → c) = 2.5 10-5Br(pp → c) = 1.2 10-3
Paola Gianotti - LNF
Exotic hadronsExotic hadrons
In the light meson spectrum exotic statesoverlap with conventional states
The QCD spectrum is much rich than that of the naive quark model also the gluons can act as hadron components
The “exotic hadrons” fall in 3 general categories:
(qq) gHybrids
Glueballs
(qq)(qq)Multiquarks
Exoti
c lig
ht
Exoti
c cc
1 -- 1-+
0 2000 4000MeV/c2
10-2
1
102
Paola Gianotti - LNFE
xoti
c lig
ht
Exoti
c cc
1 -- 1-+
0 2000 4000MeV/c2
10-2
1
102
Exotic hadronsExotic hadrons
The QCD spectrum is much rich than that of the naive quark model also the gluons can act as hadron components
The “exotic hadrons” fall in 3 general categories:
(qq) gHybrids
Glueballs
(qq)(qq)Multiquarks
In the cc meson spectrum the density of states is lower and therefore the overlap
Paola Gianotti - LNF
In the light meson region, about 10 states have been classified as “Exotics”. Almost all of them have been seen in pp...
Exotic hadronsExotic hadrons
Main non-qq candidates
f0(980) 4q state
f0(1500) 0++ glueball candidate
f0(1370) 0++ glueball candidate
f0(1710) 0++ glueball candidate
(1410); (1460) 0+ glueball candidate
f1(1420) hybrid, 4q state
1(1400) hybrid candidate 1
1(1600) hybrid candidate 1
(1800) hibrid candidate 0
2(1900) hybrid candidate 2
1(2000) hybrid candidate 1
a2’(2100) hybrid candidate 1++
Paola Gianotti - LNF
Production
all JPC available
Formation
only selected JPC
Exotic mesons are produced with rates similar to qq conventional systems
All ordinary quantum numbers can be reached ~1 b
All ordinary quantum numbers can be reached ~1 b
p
p_
G
p
p_
H
p
p_
H
Glueballs and HybridsGlueballs and Hybrids
p
p_
G
M
p
M
H
p_
p
M
H
p_
Even exotic quantum numbers can be reached ~100 pb
Even exotic quantum numbers can be reached ~100 pb
Paola Gianotti - LNF
p
p_
G
M
p
M
H
p_
p
M
H
p_production
p
p_
G
p
p_
H
p
p_
Hformation
Paola Gianotti - LNF
● Gluonic excitations of the quark-antiquark-potential
may lead to bound states
● LQCD: mH ~ 4.2-4.5 GeV ; JPC 1-+
Charmed HybridsCharmed Hybrids
● Flux tube-Model predicts HDD** (+c.c.) decaysIf mH<4290 MeV/c2→
H < 50 MeV/c2
● Some exotics can decay neither to DD nor to DD*+c.c.– e.g.: JPC(H)=0+-
• Flux-tube allowedc0,c0,c2,c2,
c,h1, h1c• Flux-tube forbidden
J/f2,J/()S
– Small number of final states with small phase space
r0=0.5fm
BaBar and Belle would expect ~300 evts. each in 5 years not competitive
Paola Gianotti - LNF
• Light gg/ggg-systems are complicated to be identified
• Oddballs: exotic heavy glueballs– m(0+-) = 4740(50)(200) MeV– m(2+-) = 4340(70)(230) MeV
• Width unknown, but!– nature invests more likely in
mass than in momentum good prob. to see in charm channels
– Same run period as hybridsMorningstar and Peardon, PRD60 (1999) 034509Morningstar and Peardon, PRD56 (1997) 4043
GlueballsGlueballs
Paola Gianotti - LNF
Mesons in nuclear matterMesons in nuclear matter
One of the fundamental question of QCD is the generation of
MASSThe light meson masses are larger than the sum of the constituent quark masses!
Spontaneous chiral symmetry breaking seems to play a decisive role in the mass generation of light mesons.
How can we check this?
Paola Gianotti - LNF
Mesons in nuclear matterMesons in nuclear matter
Since density increasein nuclear matter is possible a partial restoration of chiral symmetry
● Light quarks are sensitive to quark condensate
Evidence for mass changes of pions and kaons has been observed
● Deeply bound pionic atoms
Nucleus-Nucleus CollisionsProton-Proton Collisions
K-
K+
K-
K+
f* = 0.78f
● Kaon-production environments
Paola Gianotti - LNF
pionic atoms
KAOS/FOPI
HESR
π
K
D
vacuum nuclear mediumρ = ρ0
π+
π-
K-
K+
D+
D-
25 MeV
100 MeV
50 MeV
Mass modifications of mesons
With p beam up to 15GeV/c these studieswill be extended
Sub-threshold enhancement for D and Dmeson productionexpected signal:
strong enhancement of the D-meson cross section, relative D+ D- yields, in the near/sub-threshold region.
Mesons in nuclear matterMesons in nuclear matter
pp→ D+D-
10-2
10-1
1
10
102
103
(nb)
4 5 6 7
D+
D-
T (GeV)
in-medium
free masses
Paola Gianotti - LNF
Mesons in nuclear matterMesons in nuclear matter
The lowering of the DD thresh.
– allow ’,c2 charmonium states
to decay into this channel
3
GeV/c2 Mass
3.2
3.4
3.6
3.8
4
(13D1)
(13S1)
c(11S0)
(33S1)
c1(13P1)c1(13P0)
DD3,743,64
3,54
vacuum10
20
thus resulting in a substantial increase of width of these states
c2(13P2)
(23S1)
– states above DD thresh. would have larger width
Idea– Study relative changes of yield and width of the charmonium
state (3770).
BR into (10-5 in free space)
Predictions by Ye.S. Golubeva et al., Eur.Phys.J. A 17,(2003)275
Paola Gianotti - LNF
J/J/ Absorption in Nuclei Absorption in Nucleie-
e+
J/
p● Important for the understanding of heavy ion collisions related to QGP
● Reaction
p + A → J/ + (A-1)
→e+e
● A complete set of measurements could be done - J/, ‘, J on different nuclear target
- Longitudinal and transverse Fermi-
distribution is measurable
Paola Gianotti - LNF
s
ud
s
dd
s
ds
s
ss
0
• Use pp interaction to produce a hyperon “beam” (t~10-10 s) which is tagged by the antihyperon or its decay products
Hypernuclear PhysicsHypernuclear Physics
_
(Kaidalov & Volkovitsky)
quark-gluon string model
Paola Gianotti - LNF
- capture:
- p + 28 MeV-
3 GeV/c
Kaons _
trigger
p_
2. Slowing down and capture
of insecondary
target nucleus
2. Slowing down and capture
of insecondary
target nucleus
1.Hyperon-
antihyperonproduction
at threshold
1.Hyperon-
antihyperonproduction
at threshold+28MeV
3. -spectroscopy
with Ge-detectors
3. -spectroscopy
with Ge-detectors
Production of Double HypernucleiProduction of Double Hypernuclei
-(dss) p(uud) (uds) (uds)
Paola Gianotti - LNF
Expected Counting RateExpected Counting Rate
Ingredients (golden events)─ luminosity 2·1032 cm-2s-1 ─ +- cross section 2mb for pp 700 Hz─ p (100-500 MeV/c) p500 0.0005– + reconstruction probability 0.5– stopping and capture probability pCAP 0.20– total captured - 3000 / day
– - to -nucleus conversion probability p 0.05– total hypernucleus production 4500 /month
– gamma emission/event, p 0.5– -ray peak efficiency pGE 0.1
• ~7/day „golden“ -ray events (+ trigger)• ~700/day with KK trigger
high resolution -spectroscopy of double hypernuclei will be feasible
Paola Gianotti - LNF
Other physics topicsOther physics topics
Cross section σ ≈ 2.5pb @ s ≈10 GeV2
L = 2·1032 cm-2 s-1→ 103 events per month
• Reversed Deeply Virtual Compton Scattering
• CP-violation (D/ – sector)- D0D0 mixing
SM prediction < 10-8
- compare angular decay asymmetries for
SM prediction ~ 2·10-5
• Rare D-decays:D+→+ (BR 10-4)
W+
c
d
Paola Gianotti - LNF
Detector requests:
• nearly 4 solid angle (partial wave analysis)• high rate capability (2·107 annihilations/s)• good PID (, e, , , K, p)• momentum resolution (~1%)• vertex info for D, K0
S, (c = 317 m for D±)• efficient trigger (e, , K, D, )• modular design (Hypernuclei experiments)
General Purpose DetectorDetector
Paola Gianotti - LNF
Detector Detector (top view)(top view)
target spectrometer forward spectrometer
micro vertexdetector
electromagneticcalorimeter
DIRC:Detecting InternallyReflectedCherenkov light
straw tubetracker
mini driftchambers
muon counter
Solenoidalmagnet
iron yoke
Paola Gianotti - LNF
PANDA DetectorPANDA Detector
Paola Gianotti - LNF
PANDA CollaborationPANDA Collaboration
•At present a group of 300 physicists
from 49 institutions of 11 countries
Basel, Beijing, Bochum, Bonn, Catania, Cracow, Dresden, Edinburg, Erlangen, Ferrara,
Franhfurt, Genova, Giessen, Glasgow, KVI Groningen, GSI, FZ Jülich I + II, JINR, Katowice,
Lanzhou, LNF, Los Alamos, Mainz, Milano, Milano Politecnico, Minsk, TU München,
Münster, Northwestern, BINP Novosibirsk, Pavia, Silesia, Stockolm, Torino I + II, Torino
Politecnico,Trieste, TSL Uppsala, Tübingen, Uppsala, SINS Warsaw, AAS Wien
Basel, Beijing, Bochum, Bonn, Catania, Cracow, Dresden, Edinburg, Erlangen, Ferrara,
Franhfurt, Genova, Giessen, Glasgow, KVI Groningen, GSI, FZ Jülich I + II, JINR, Katowice,
Lanzhou, LNF, Los Alamos, Mainz, Milano, Milano Politecnico, Minsk, TU München,
Münster, Northwestern, BINP Novosibirsk, Pavia, Silesia, Stockolm, Torino I + II, Torino
Politecnico,Trieste, TSL Uppsala, Tübingen, Uppsala, SINS Warsaw, AAS Wien
http://www.gsi.de/hesr/panda
Spokesperson: Ulrich Wiedner – Uppsala deputy
Austria – China - Germany – Italy – Netherlands – Poland – Russia – Sweden – Switzerland - U.K. – U.S.
Paola Gianotti - LNF
ConclusionsConclusions
perform high resolution spectroscopy with p-beam in formation experiments:
E ≈ Ebeam
produce, with high yields, gluonic excitations: glueballs, hybrids, multi-quark states
≈ 100 pb
study partial chiral symmetry restoration by implanting mesons inside the nuclear medium
produce hyperon-antihyperon taggable beams
Thanks to the new GSI HESR facilityp will be used to...
Paola Gianotti - LNF
Topic Competitor
ConfinementCharmonium
all cc states with high resolution
CLEO-C only 1–– statesformed
Gluonic Excitations
charmed hybridsheavy glueballs
CLEO-C light glueballsHall-D light hybrids
Nuclear Interactions
D-mass shift
J/ absorption (T~0)Dane K-mass shift
Hypernuclei-spectroscopy of- and -hypernuclei
JHF single HN
Dane high luminosity
Open Charm Physics
Rare D-DecaysCP-physics in Hadrons
CLEO-C rare D-DecaysCP-physics in D-Mesons
Competition Competition BES, CLEO, DaBES, CLEO, Dane, HallD, JHFne, HallD, JHF
Paola Gianotti - LNF
Final state Cross section # rec. events
Meson resonance + anything
100mb 1010
50mb 1010
2mb 108
DD 250nb 107
J/(→e+e,) 630nb 109
2(→ J/) 3.7nb 107
cc 20nb 107
cc 0.1nb 105
HESR/ expected counting ratesHESR/ expected counting rates
One year of data taking ≈ 1-2(fb)-1