C. Schwarz

Experiments with a cooled p beam on an internal target

• Physics program

• Detector set-up

Carsten Schwarz

p

e- cooler detector

High Energy Storage RingHESR

Pmax = 15 GeV/cLmax = 2·1032 cm-2 s-1

Ø < 100 μmΔ p/p < 10-5

C. Schwarz

Physics programCharmoniumspectroscopy

Medium modificationsof D mesons and J/Ψ in nuclei

Hypernuclei CP violation

GlueballsHybrids

C. Schwarz

Medium modificationsof D mesons and J/Ψ in nuclei

Continuation of present GSI physicsFOPI, KAOS, HADES, …HESR

Signal: medium modification ofproduction threshold,resonance widthe.g. Ψ’, χ2

Absorption cross section of J/Ψ in nuclei (ρ=ρ0).

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

C. Schwarz

• Charmonium gives information about QCD confinement potential.

• Many states are still missing.

• pp: direct population of all states.

• HESR allows investigation of states above DD threshold.

• Cooled beams with Δp/p≤10-5 allow high precision scan of resonances.

Charmoniumspectroscopy

40 keV

Crystal Balle+e-

C. Schwarz

Hypernuclei

-

3 GeV/c

K+KTrigger

_

secondary target

-(dss) p(uud) (uds) (uds)

study of interaction

p

C. Schwarz

GlueballsHybrids

qqg ggg

Hybrid Glueball

Normal meson: 2 fermionsP = (-1)L+1

C = (-1)L+S

Excited glue: bosonic degree of freedom→ exotic quantum numbers eg. JPC=1-+, 0--, 0+-, 2+-…→ normal quantum numbers

Signal:exotic quantum numbers:

partial wave analysisnormal quantum numbers:

model comparison (LGT)

mixing with normal mesonscharm sector: few resonances

with small widths

qq

Meson

C. Schwarz

CP violation in Hyperon decay

p + p → Λ +Λ ↓ ↓ pπ- pπ+

• Measure decay asymmetry of angular distribution of p relative to Λ-Hyperon momentum.

• Ip(θp) ~ 1+α cos(θp) for Λ

• Ip(θp) ~ 1+α cos(θp) for Λ

• CP conservation: α = - α

• Signal for CP violation:

Theoretical prediction: ~10-4 ~ 10-5

Experiment: 1010 reconstructed ΛΛ

L=2·1032 cm-2 s-1 → >1 year running

A

C. Schwarz

HESR-Detector

Formation of Ψ’ and decay in myons

Ψ’→μ+μ-

Ψ’→J/Ψ + X ↓ μ+μ-

electrons similar→ calorimeter for large angles.

Simulations with Pluto event generator

C. Schwarz

HESR-detector

Internal target

forward spectrometertarget spectrometer

Heavy charmed mesons decay inlight products with large pt.Solenoid is important.

top view

C. Schwarz

HESR detectorside view

C. Schwarz

CostsSolenoid 2.5 M€

Calorimeter (target) 12.5 M€

Tracking (pixel detector, straw tubes) 3.0 M€

Cherenkov 3.5 M€

Hypernuclei (read out electronics,micro tracker) 2.0 M€

Varia 1.9 M€

Trigger 1.5 M€

Infrastructure 2.0 M€

Contingency 2.0 M€

Sum 30.9 M€

C. Schwarz

Collaborations: Working group:

LEAR, COSY, SATURNE community

Munich GermanyBochum “Giessen “Dresden “Erlangen “Jülich “Ferrara ItalyTurin “Krakow PolandWarsaw “

T. Barnes D. BettoniR. Calabrese M. DürenS. Ganzhur V. HejnyH. Koch U. LynenV. Metag H. OrthS. Paul K. PetersJ. Pochodzalla J. RitmanL. Schmitt C. SchwarzK. Seth W. WeiseU. Wiedner