DIRCs for PANDA M. Hoek for the PANDA Cherenkov Group

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Physics at PANDA Precision Hadron Spectroscopy Exotic States (Glueballs, Hybrids) In-Medium Modifications Nucleon Structure Hypernuclei Non-perturbative QCD

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Introduction – PANDA Detector Target Spectrometer Forward Spectrometer Beam Target Laminated Yoke Magnet Coils Central Tracker Forward Tracker Barrel EMC Endcap EMC

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 PANDA Target Spectrometer – Barrel DIRC Endcap DIRC Barrel DIRC acceptance 140° - 22° Endcap DIRC acceptance 5° - 22° J/Ψ → K + K - γ Beam

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 No Lens PANDA Barrel DIRC Design Radiator Bars Focussing Optics Radiator Bar First Lens Second Lens 2.3m 0.4m

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Endcap DIRC – Focussing Lightguide Design ~2.5m Endcap EMC Radiator Disc Imaging Units φ Fused Silica Lithium Fluoride Position-sensitive Photon Detector

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Endcap DIRC – Time-of-Propagation Design

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Challenges – Radiator Surface Quality Standard Polish Advanced Polish

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Challenges – Radiator Radiation Hardness Schott LF5 Glass 10 Mrad 1 Mrad 100 krad (estimated PANDA lifetime ) 100 krad (estimated PANDA lifetime ) Suprasil 1 Fused Silica 10 Mrad 1 Mrad 100 krad (estimated PANDA lifetime ) 100 krad (estimated PANDA lifetime )

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Challenges – Chromatic Dispersion Blurring of Cherenkov Ring Image 0.5 GeV/c Kaon Photon Time-of- Propagation 100ps - 200ps resolution 2 GeV/c Kaon

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Challenges – Chromatic Dispersion Absolute Shift Angular Distribution Distribution after LiF Element Lithium Fluoride Fused Silica SiO 2 Fused Silica SiO 2 Fused Silica SiO 2 Fused Silica SiO 2

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Challenges – Photon Detector Barrel DIRC Photon Detector Barrel DIRC Photon Detector 1Tesla 1.5Tesla 0.7Tesla

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Challenges – Photon Detector (MCP-PMT)

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 MCP-PMT Single Photo-Electron Timing

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 MCP-PMT Rate Stability

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 MCP-PMT Lifetime Ion Backflow Barrel DIRC ~ 0.8 C/cm 2 /year Endcap DIRC ~ 4 C/cm 2 /year (Focussing Design) ~ 10 C/cm 2 /year (ToP Design) ~ 50% loss (at 500nm) ~ 50% loss (at 500nm) 0.11 C/cm 2

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 First Results – Barrel DIRC Radiator Bar Lens MCP- PMTs

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 First Results – Endcap DIRC 2 GeV Proton Beam Polar Angle θ Data Simulation

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Thank You

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Backup Slides

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 Barrel DIRC Performance

M. Hoek – Probing Strangeness in Hard Processes – Laboratori Nazionali di Frascati, October 2010 MCP Uniformity