The PANDA Experiment, which is located at the High Energy Storage Ring at the FAIR accelerator
center in Darmstadt, Germany, is optimized for questions of hadron physics.
With this detector it will be possible to discover new states and measure their line shapes as well as the
line shapes of already known states very precisely.
To normalize the energy scan measurements exact knowledge of the luminosity is required.
The luminosity at PANDA will be determined from the angular distribution of elastical antiprotonm
proton scattering. In order to achieve an absolute measuring accuracy of 5% , the tracks of the scattered
antiprotons will be measured by four planes of thinned silicon detectors (HV-MAPS).
HV-MAPS are pixel sensors with integrated readout electronics. They will be operated with a reverse
voltage of 60 volts to increase their radiation hardness.
The four detector planes consist of CVD-diamonds on which the sensors are clued. To reduce the
multiple scattering the detector is operated in a vacuum.
The concept of the luminosity detector is presented and technical aspects such as the vacuum system,
cooling, electronics, and sensors are discussed, as well as insights into data analysis.
The PANDA-Experiment will be a fixed target experiment at the future FAIR-accelerator center at Darmstadt, Germany. As the experiment is designed for high precision measurements with an antiproton beam, especially in the charm sector of hadron spectroscopy, a precise knowledge of the luminosity is crucial.
The determination of the luminosity will be done by measuring the angular distribution of elastically scattered antiprotons at very small scattering angles between 3 and 8 mrad. Therefore their tracks will measured by four layers of thinned HV-MAPS silicon sensors of 50μm thickness. To minimize the multiple scattering, the measurement is performed in vacuum. As the sensors will dissipate up to 7mW/mm^2, an active cooling is mandatory. To achieve this while maintaining a low material budget, the sensors will be glued on 200 μm thin CVD-diamonds which are clamped in an actively cooled aluminium heatsink outside of the acceptance. An excellent thermal contact to the stainless steel pipe for the coolant is ensured by melting the aluminium around the pipe before machining the heatsink. The poster will present the mechanical design and the cooling system.
The PANDA experiment at the international accelerator Facility for Antiproton and Ion Research in Europe (FAIR) near GSI, Darmstadt, Germany will address fundamental questions of hadron physics. Excellent particle identification is required to achieve the PANDA physics goals. Hadronic particle identification (PID) in the PANDA target spectrometer will be delivered by two DIRC (Detection of Internally Reflected Cherenkov light) counters. The Barrel DIRC will cover the polar angle range of 22−140 degree and is designed to provide pion/kaon separation for momenta between 0.5 GeV/c and 3.5 GeV/c with a separation power of at least 3 standard deviations. Several reconstruction algorithms have been developed to determine the performance of the detector. The "geometrical reconstruction" determines the Cherenkov angle relying primarily on the position of the detected photons. The "time imaging", however, utilizes both position and time measurements by directly performing the maximum likelihood fit. GEANT4 simulations and experimental data from prototype tests at the CERN PS were used to optimize the performance of the algorithms. We will discuss detailed aspects of both reconstruction approaches.