A search for μ-e conversion in muonic gold Bertl, W.; Engfer, R.; Hermes, E.A. ...
The European physical journal. C, Particles and fields,
8/2006, Letnik:
47, Številka:
2
Journal Article
Recenzirano
Odprti dostop
We report on a search for μ-e conversion in muonic gold performed with the SINDRUM II spectrometer at PSI. The measurement resulted in Γ(μ-Au→e-Aug.s.)/Γcapture(μ-Au)<7×10-13 (90% C.L.).
Large-scale physics experiments running at high interaction rates place a high demand on the data acquisition system (DAQ) responsible for transporting the data from the detector to the storage. The ...antiProton ANihilation at DArmstadt (PANDA) at the facility for anti-proton and ion research (FAIR) is one such experiment of the future that will not use fixed hardware triggers; instead, the event selection is based on real-time feature extraction, filtering, and high-level correlations. A firmware framework for such real-time data processing has been developed and tested with hardware setup for a PANDA Forward Tracker (FT) prototype. The solution is applicable for other detector subsystems based on the so-called Trigger Readout Board (TRB) data read-out system.
A complete, general solution for collecting and processing data from gaseous tracking detectors in high-rate applications has been developed. The readout chain consists of front-end modules equipped ...with PASTTREC ASIC chips and trigger readout boards version 3 (TRBv3) as a readout platform. The platform is accompanied by dedicated control, monitoring, and data quality assessment software. The entire system has been evaluated with a tracking system based on straw detectors in laboratory and in-beam experiments. In this paper, we present key elements of the system as well as results of various tests. The measured PASTTREC operation characteristics and the TRBv3 specification used for the readout allow us to adapt and to integrate it to the existing HADES spectrometer and the PANDA detector, an experiment under construction, both located at the FAIR facility in Darmstadt.
.
The
Λ
polarization, the analyzing power, and the
Λ
spin transfer coefficient of the reaction
pp
→
pK
+
Λ
were measured at beam momenta of 2.70GeV/c and 2.95GeV/c corresponding to excess energies of ...122MeV and 204MeV. While the analyzing power and the spin transfer coefficient do not change significantly with the excess energy, the
Λ
polarization varies strongly and changes its sign. As this is the first measurement of polarization observables below an excess energy of 200MeV, the change of the sign of the
Λ
polarization was not observed before. The high statistics of the data (
≈
200 k events for each momentum) enables detailed studies of the dependence of the
Λ
polarization and the analyzing power on the center-of-mass momentum of the particles. The results of the spin transfer coefficient are in qualitative agreement with the DISTO experiment. The
Λ
polarization data of 2.95GeV/c are only conform with the DISTO experiment, while both the 2.70GeV/c and 2.95GeV/c data differ strongly from all previous measurements, whether exclusive or inclusive.
The identification of charged particles based on energy losses in straw tube detectors has been simulated. The response of a new front-end chip developed for the PANDA straw tube tracker was ...implemented in the simulations and corrections for track distance to sense wire were included. Separation power for p−K, p−π and K−π pairs obtained using the time-over-threshold technique was compared with the one based on the measurement of collected charge.
The PANDA (AntiProton Annihilations at Darmstadt) experiment is being built at the new Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. PANDA will measure antiproton-proton ...annihilation reactions in the charm quark mass range to investigate the nature of the strong interaction. This particle physics experiment will run at very high reaction rates of 10-20 MHz. Our work is related to an ADC (analog-to-digital converter) based data acquisition system for the PANDA Straw Tube Tracker (STT). The STT will be able to deliver data rates up to 20 GByte/s through over 4600 signal channels and could require major efforts for the hardware implementation as well as high offline processing power. Test beam studies were carried out in order to specify a proper system architecture with feasible hardware and to reduce output data stream to a level suitable for offline processing. We analyze the straw tube response to both the proton beam and 55 Fe irradiation. Furthermore, we present real-time processing using the neighboring straw information and introduce the technique to reconstruct the tracks.
The straw tube tracker of the ANDA experiment Costanza, S.; Benussi, L.; Braghieri, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1-3
Journal Article
Recenzirano
MathML equationANDA is a new experiment that will be installed at HESR, the new antiproton storage ring under construction as a part of the FAIR facility at Darmstadt, Germany. This experiment, that ...will investigate QCD in the charmonium mass regime and other aspects of particle and nuclear physics, will be a fixed target detector with a central spectrometer and a forward one. The central tracker will provide information about decay vertices, momenta and types of charged particles emitted after MathML equation annihilations. The design of the Straw Tube Tracker (STT) together with experimental results of the R&D phase are presented here.
We report on a determination of the analyzing power Ay in the p→p→ppω reaction studied with the TOF spectrometer located at the COSY-accelerator (Forschungszentrum Jülich, Germany). This spectrometer ...is very well suited for polarization measurements due to its rotational symmetry and full coverage of the azimuthal angle. For a beam momentum of p=3065 MeV/c corresponding to an excess energy of ϵ=129 MeVAy is found to be compatible with zero.
This paper describes the deduction of pulse arrival times from digital waveforms recorded with a multichannel data-acquisition (DAQ) system. A linear rise approximation (LRA) arrival timing method ...provides restricted timing resolution for pulses with nonlinear rise. It reaches 1/20th of the sampling period, if the relation between signal shaping and sampling rate is optimized. We introduce a nonlinear rise approximation (nLRA), which reduces the sampling phase error (SPE) down to less than 1/100th of the sampling period. The proposed timing algorithm uses a single free parameter that can easily be adjusted for various radiation detectors. The technique permits using a rather slow pulse shaping and low sampling rates, thus strongly reducing power consumption and the costs of the system. A high-density DAQ system integrating over 2000 channels inside an OpenVPX crate is presented. A prototype has been tested in the proton beam at cooler synchrotron (COSY) at Jülich Research Center (Germany).
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