Conference (CON)

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.

High event rates of up to 20 MHz and continuous detector readout makes the event filtering at PANDA a challenging task. In addition, no hardware-based event selection will be possible due to the similarities between signal and background. This makes PANDA among a new generation of experiments utilizing a fully software-based event filtering. Classically, detector hits are pre-sorted into events by the hardware filter before being passed to the software-based event filter with track reconstruction and event building. Track reconstruction will play a key part in the online filtering at PANDA where it will be used iteratively together with the event building.

To ensure the quality of the track reconstruction, the existing quality assurance task has been modified to be able to cope with free streaming data. This talk will address the data stream at PANDA as well as the candidates for online track reconstruction algorithms for free streaming data based e.g. on the Cellular Automaton. The quality assurance procedure and the results from the tracking at different event rates and level of event mixing is presented.

The PANDA experiment of the FAIR facility will address open
questions in hadron physics using antiproton beams in the
momentum range of 1.5-15 GeV/c.
The antiprotons are stored and cooled in the High Energy
Storage Ring (HESR) and allow high precision spectroscopy in
the energy range of closed and open charm.
Two Cherenkov detectors using the principle of Detection of
Internally Reflected Cherenkov light (DIRC) will provide
excellent PID in the PANDA target spectrometer.
The Endcap Disc DIRC separates pions from kaons better than
3σ up to momenta of 4 GeV/c in the forward direction, for polar
angles from 5∘ to 22∘.
It uses a fused silica radiator disk, consisting of four
optically isolated quadrants.
The Cherenkov photons are imaged on Microchannel-Plate PMTs
(MCP-PMTs) by focusing lightguides.
The Barrel DIRC cleanly separates pions from kaons for polar
angles in the range of 22∘ - 140∘ and momenta up to 3.5 GeV/c.
The barrel is formed by 16 sectors, each comprising three narrow
fused silica radiator bars, with a flat mirror attached to
one end and a spherical lens attached to the other, and a
large fuse silica prism, coupled to each group of three lenses.
The Cherenkov light is focused on the back side of the prism,
where an array of lifetime-enhanced MCP-PMTs detects the photons.

The designs are simulated and validated in test beams with
prototypes and the Technical Design Reports of both devices
have recently been completed.
While mass production of some of the components has already
started, the R&D for other important items, like the readout
electronics or the shape and materials of the mechanical support,
is still ongoing.
This talk describes the status of the two DIRC projects and will
discuss the remaining R&D activities.

PANDA is one of the four experimental pillars of the upcoming FAIR facility in Darmstadt, Germany. In PANDA, an antiproton beam with an energy between 1.5 and 15 GeV/c will interact in a hydrogen or nuclear target, allowing for studies of various aspects of non-perturbative QCD. Motivated by the high interaction rates and the diverse physics goals of the experiment, a triggerless readout approach will be employed. In this approach, each detector subsystem will be equipped with intelligent front-end electronics that independently identify signals of interest in real time. In order to detect the most forward-directed photons, electrons and positrons in PANDA, a shashlyk-type calorimeter is being constructed. This detector consists of 1512 individual cells of interleaved plastic scintillators and lead plates, and has been optimised to have a relative energy resolution of approximately 3%/sqrt(GeV) and a time resolution of approximately 100 ps/sqrt(GeV). The signals from this detector will be digitised by sampling ADCs and processed in real time by FPGAs. As part of the triggerless approach, these FPGAs will perform so-called feature extraction on the digitised signals, where the pulse-height and time of incoming pulses are extracted in real time. A substantial pileup rate is expected, and it is foreseen that the chosen algorithm should enable reconstruction of such events. The work presented here has consisted of developing a detailed Geant4-based model of the shashlyk calorimeter and readout system, calibrating this model against testbeam data, and using it to evaluate potential feature-extraction algorithms for the PANDA shashlyk calorimeter.

The PANDA detector at the international accelerator Facility for Antiproton and Ion Research in Europe (FAIR) in Darmstadt (Germany)
will address fundamental questions of hadron physics in high-energy antiproton collisions with fixed hydrogen and nuclear targets. 

The PANDA Forward RICH (FRICH) is intended for identification of charged particles with forward polar angles below 5°–10°
and momenta from 3 to 15 GeV/c. PANDA FRICH will feature a multilayer focusing aerogel radiator, photon detection by Hamamatsu H12700 MaPMTs
read out by DiRICH front-end electornics. Precisely aligned flat mirrors will collect Cherenkov light on the photon detector.
Results of optical measurements of the detector components are presented.

The PANDA Forward RICH prototype was tested at 3GeV electron beam at the Budker INP in 2019.
Single photon resolution was obtained that agrees with expectations.

Last minute contribution to the "Build and Deployment" Session at the EPICS Collaboration Meeting

For the PANDA Detector Control system currently the possibility of using Docker Images to build and deploy the controls system software is evaluated. A first test container is build and test will be made in the near future

The future PANDA experiment with a next generation detector will focus on hadron
spectroscopy. It will use cooled anti-proton beams
with a momentum between 1.5 GeV/c and 15 GeV/c
interacting with various targets. This allows to direct
form all states of all quantum numbers and measure
there widths with an accuracy of a few tens of keV
The experiment will be located at the Facility for
Anti-Proton and Ion Research in Germany, which is currently under construction.
The electromagnetic target calorimeter of the PANDA experiment has the challenging aim to
detect high energy photons with excellent energy resolution over the full dynamic range from
15 GeV down to a few tens of MeV inside a 2T solenoid. To reach this goal, improved
PbWO 4 scintillator crystals (PWO-II) cooled down to −25°C have been chosen. They provide
a fast decay time for highest count rates, short radiation length for compactness, improved
light yield for lowest thresholds and excellent radiation hardness. The target calorimeter itself
is divided into a barrel shaped structure and two endcaps. Individual crystals will be read out
with two precisely matched large area avalanche photo diodes. In the very inner part of the
forward endcap, vacuum phototetrodes will be used instead.
The talk will give an overview of the PANDA experiment and focuses on its calorimeter
including the scintillator material and the production status. Furthermore, the construction and
assembly procedure will be presented.
This work was upported by the BMBF.

Microchannel-plate (MCP) PMTs were identified as the only suitable photon sensors for the DIRC detectors of the PANDA experiment at FAIR. PANDA is a hadron physics experiment which employs a high intensity antiproton beam of up to 15 GeV/c to perform high precision measurements of, among others, objectives like charmonium spectroscopy and search for gluonic excitations. As the long-standing aging problems of MCP-PMTs were recently overcome by coating the MCP pores with an atomic layer deposition (ALD) technique, we have investigated further improved 2-inch MCP-PMTs. The latest PHOTONIS devices reach a DQE = QE*CE > 25% and lifetimes of >20 C/cm2 IAC without any sign of aging. Also the newly developed 2-inch MCP-PMTs of Hamamatsu are maturing and now usable in high rate environments. In this talk the status of our long-term lifetime measurements and the performance of the currently most advanced ALD-coated MCP-PMTs will be presented. In addition, first results obtained with a new quality assurance setup for MCP-PMTs will be discussed. This setup consists of a modular PADIWA/TRB DAQ system to measure the response of up to 300 anode pixels simultaneously. The system is very flexible and allows a glance “inside the MCP-PMT”: background parameters like position dependent dark count rates and ion afterpulsing will be accessible as well as temporal and spacial distributions of recoil electrons and the effects of electronic and charge-sharing crosstalk among the anode pixels.

The future PANDA experiment with a next generation detector will focus on hadron spectroscopy. It will use cooled anti-proton beams with a momentum between 1.5 GeV/c and 15 GeV/c interacting with various targets. This allows to direct form all states of all quantum numbers and measure there widths with an accuracy of a few tens of keV. The experiment will be located at the exceptional Facility for Anti-proton and Ion Research in Germany, which is currently under construction.
The electromagnetic target calorimeter of the PANDA experiment has the challenging aim to detect high energy photons with excellent energy resolution over the full dynamic range from 15 GeV down to a few tens of MeV within a 2T solenoid. To reach this goal, improved PbWo4 scintillator crystals, cooled down to −25°C have been chosen. They provide a fast decay time for highest count rates, short radiation length for compactness, improved light yield for lowest thresholds and excellent radiation hardness.
The target calorimeter itself is divided into a barrel and two endcaps. The individual crystal will be read out with two precisely matched large area avalanche photo diodes. In the very inner part of the forward endcap vacuum phototetrodes will be used instead.
The talk will give an overview of the PANDA experiment and focuses on its calorimeter including the scintillator material and its production status. Furthermore, the construction and assembly procedure of the calorimeter will be presented.