A ntikaonic M atter A t D A Φ NE: E xperiments with U nraveling S pectroscopy

P. Kienle, IX International Conference on Hypernuclear and Strange Particle Physics, 10-14 October 2006

AntikaonicMatterAtDAΦNE: Experiments withUnravelingSpectroscopy

AMADEUS

The AMADEUS ProjectP.Kienle, TU Munich and SMI Vienna


Letter of Intent

Study of deeply bound kaonic nuclear states

at DANE 2

AMADEUS Collaboration

March 2006

111 scientists from 33 Institutes of 13 Countries signed the Letter of Intent


Phase Diagram of Hadronic Matter

Study of the Phase Diagram at High Densities and T=0 Using Deeply Bound Kaonic Nuclear Clusters


Λ(1405) the Doorway to Antikaonic Nuclei

Strong Antikaon-Proton attraction below the Λ(1405) resonance. Repulsion above it as shown experimentally by Re a(K-p).


Decrease of K- Mass in a Nuclear Medium Strong Binding by Attractive K-N Force


Antikaon Production in Ni-Ni Collisions

P. Kienle, A. Gillitzer

Proc. Int. Conf. Nucl.Phys. (1996) Wilderness,SA

Ed,:Stöcker, Gallmann, ,Hamilton, World Scientific

G,Q. Li, C.M. Ko, X.S. Fang, Phys. Lett. B329, (!994) 149

Indication of a decrease of the K- mass of ~200 MeV in a nuclear medium with n/n0 ~ 2


Prediction of Lightest Kaonic Nuclear Systems

Strong K- binding in a nuclear medium discussed by Wycech (1986) and p-wave contribution (EXA05)


Summary of the Search for Deeply Bound Kaonic States

All experimental data are so far Missing Mass or Invariant Mass Spectra. No exclusive MM and IM data needed for proof


Λ-p Invariant Mass Spectra from Heavy Ion Collisions. FOPI Data


AMADEUS STRATEGY

• Confirm or reject the existence of kaonic nuclear clusters by an exclusive measurement using 4-detection of all reaction and decay products for construction of missing mass and invariant mass spectra.

• Use (K-stopped,N) reaction with mono-energetic K- from Φ decay produced by DAΦNE.

• Use the high performance KLOE detector implemented with a cryogenic gas target and a stopped K- trigger system


Realization of the AMADEUS Project

• Determination of the neutron detection efficiency of the KLOE electromagnetic calorimeter

• Implementation of a cryogenic gas target and a K- stop position detection system

• Analysis of the data from K- stopped in the 4He gas of the KLOE drift chamber


Reaction Channels (simplified)


KLOE – EMC

KLOE –Drift Chamber

Possible setupfor AMADEUSwithin KLOE:

Cryogenic targetInner trackerKaon trigger

6 m

AMADEUS Implemented in KLOE


Signature for ppnK- Decay

decay: ° + p + n

p + -

4He + K- ppnK- + n

n

n

p

p

-

-


Event Display for ppnK- Decay

ppnK-

0 + n + p p

Interaction region

Cryogenic target cell

TPC-GEM

Segmented degrader

Kaon trigger

K-stopped

p

n

p-

-

KLOE-DC

KLOE-EMC


Determination of the KLOE CalorimeterEfficiency for Neutrons


Monte Carlo KLOE Calorimeter


AMADEUS with TPC and GEM Read-out

AMADEUS Setupsecond version


3 ×

10-3

0 cm

2

p

rodu

ctio

n cr

oss

sect

ion

production rate for charged kaon pairsR = L b = 1500 s-1

peak

lum

inos

ity

10

33 c

m-2 s

-1

produced K± per month: 31 × 108 (80% duty cycle assumed)

40% are stopped in the cryogenic He gas target (15% liq. He density, ~ 5 cm thick) 12.5 × 108 K- 4He atoms per month

for 10-3 cluster formation yield: 12.5 × 105 kaonic clusters formed in one month

Efficiency of tracking & identification K± & detection of decay products ~ 105 events per month (~ 1000 pb-1)

0.49

bra

nchi

ng ra

tio fo

r K±

MonteCarlo Simulations for AMADEUSwith Optimized Degrader and Cryo-target


Start Program of AMADEUS

• Reactions used: 3He(K-stopped,n)ppK-

4He(K-stopped,n/p)ppnK-/pnnK-

• Complete determination of all reaction and decay channels by detection of all charged particles, neutrons, and γ-rays

• Deduce from such exclusive data: Binding energies, total and partial widths, angular momenta, isospins, sizes, densities, etc


Pre-experiment: Proposal to KLOE


Detection of Reactions in 4He of Drift Chamber


Kaon production rate: ~ 150 K- s-1 (for L ~1032 cm-2 s-1)

N = L b = 2.9 × 109

2 fb

-1 = 2

× 1

039 c

m-2

i

nteg

rate

d lu

min

osity

0.49

bra

nchi

ng ra

tio fo

r K±

Total number of produced charged kaon pairs for L = 2 fb-1

~ 0.3% stopped in the gas of the chamber

3 × 10-3 × 2.9 × 109 = 8.8 × 106 K- 4He atoms

For a cluster yield of 10-3 we have ~ 8800 clusters

With efficiency of tracking & identification of K+/-

&detection of decay products 1000-2000 reconstructed clusters

3 ×

10-3

0 cm

2

p

rodu

ctio

n cr

oss

sect

ion

AMADEUS MonteCarlo:K-clusters in existing KLOE data


Conclusion and Summary

The AMADEUS project plans to use a dedicated 4-detector capable of detecting all charged and neutral particles emitted in the formation and decay of kaonic nuclear clusters for a definitive clarification of their debated existence.

For the realisation of the AMADEUS set up a cryogenic target, a kaon trigger and an inner tracker must be implemented in the KLOE detector

A ntikaonic M atter A t D A Φ NE: E xperiments with U nraveling S pectroscopy

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