The PANDA experiment at FAIR will perform world class physics studies using high-intensity
cooled antiproton beams with momenta between 1.5 and 15 GeV/c. A rich physics program
requires very good particle identification (PID). Charged hadron PID for the barrel section
of the target spectrometer has to cover the angular range of 22-140deg and separate pions from
kaons for momenta up to 3.5 GeV/c with a separation power of at least 3 standard deviations.
The system that will provide it has to be thin and operate in a strong magnetic field. A ring
imaging Cherenkov detector using the DIRC principle meets those requirements. The design
of the PANDA Barrel DIRC is based on the successful BABAR DIRC counter with several
important changes to improve the performance and optimize the costs. The design options are
being studied in detailed Monte Carlo simulation, and implemented in increasingly complex
system prototypes and tested in particle beams. Before building the full system prototypes
the radiator bars and lenses are measured on the test benches. The performance of the DIRC
prototype was quantified in terms of the single photon Cherenkov angle resolution and the
photon yield. Results for two full system prototypes will be presented. The prototype in 2011
aimed at investigating the full size expansion volume. It was found that the resolution for
this configuration is at the level of in good agreement with ray tracing simulation results. A
more complex prototype, tested in 2012, provided the first experience with a compact fused
silica prism expansion volume, a wide radiator plate, and several advanced lens options for
the focusing system. The performance of the baseline configuration of the prototype with
a standard lens and an air gap met the requirements for the PANDA PID for most of the
polar angle range but failed at polar angles around 90deg due to photon loss at the air gap.
Measurements with a prototype high-refractive index compound lens without an air gap at a
polar angle of 128deg beam angle showed a good resolution of signa(thetaC) = 11.8 +- 0.7 mrad and a high
photon yield of Nph = 26.1 +- 0.4. Even at polar angles close to 90deg the photon yield with
this lens exceeded 15 detected photons per particle, meeting the PANDA Barrel DIRC PID
requirements for the entire phase space and demonstrating that the compact focusing DIRC is
a very promising option for PANDA.
The PANDA experiment at FAIR will study fundamental questions of strong
interaction with high precision. Efficient particle identification for a wide momentum
range and the full solid angle is required for successful reconstruction of the
benchmark channels of the broad PANDA physics program. For this purpose a compact
ring imaging Cherenkov detector is being developed for the barrel region of the
PANDA detector. The concept and the baseline design of the PANDA Barrel DIRC
were inspired by the BABAR DIRC and improved with important modifications,
like fast photon timing, a compact expansion volume, and focusing optics.
The required detector resolution was defined based on the PANDA PID specifications
using the phase space distributions of the final state kaons produced in
selected benchmark channels. To optimize the PANDA Barrel DIRC design in terms
of performance and cost the baseline detector geometry and a number of design options
were implemented in the simulation. The key options include the radiator
dimensions, two types of expansion volume shapes, and a variety of focusing systems.
The performance of the detector designs was quantified in terms of single
photon Cherenkov angle resolution and photon yield. It was found that the number
of radiators can be reduced by about 40% without loss in performance. A compound
spherical lens without air gap was found to be a promising focusing system. An optimized
Barrel DIRC design meeting the PID requirements includes three radiator
bars per flat section, the compound lens without air gap, a compact prism-shaped
EV, and a total of 192 Microchannel-Plate PMTs as photosensors. The number
of electronic channels can be halved without loss in performance by combining two
neighbouring pixels. For such a detector design the total cost will be significantly reduced
compared to the baseline version while still meeting or exceeding the PANDA
PID performance goals.
The PANDA experiment is a multi-purpose particle detector, investigating hadron physics topics in the strange and charm quark mass regime. PANDA will measure antiproton-proton annihilation reactions at the FAIR complex, which is currently under construction. Caused by the initial reaction, signal and background events are similar to each other. Hence, self-triggering readout electronics is required throughout all sub-detectors. The innermost sub- detector, the Micro Vertex Detector, is based on silicon sensors with pixel and microstrip segmentation. This thesis describes the development of a readout solution (PASTA) for the microstrip sensors and the preparations for a characterization setup to perform laboratory measurements with this readout prototype. Furthermore, an exploratory study on the reconstructability of the reaction pp→Ξ+Ξ−(1690) with PANDA's software framework is presented.
A test system for sensor characterisation and QA has been set up.
High precision measurements of the sensor characteristics can be performed with the use of a
dedicated test board. Also, Non-destructive characterisation and QA can be performed with a
probestation. The leakage current and capacitive characteristics of the whole sensor as well as
individual strips have been measured.
The test system can be used for characterisation of the final sensors which are expected to be
delivered before the second half of 2015. As the final sensors have a smaller pitch, with the
same dedicated test board every 75th strip of full length and every
30th strip of varying length can be contacted individually