The proposed silicon detector concept for the international linear collider has a barrel and end cap muon systems. The scintillator based muon system prototype has 256 scintillating strips, ...wavelength-shifting fibers, and clear fibers connected to multianode photo multiplier tubes (MAPMT). Six Hamamatsu H7546B tubes were used. To understand strip output, each of 384 MAPMT outputs was independently measured at a given luminous flux and the same photocathode to anode voltage of 800 V. For the test, a custom made source of light was used. The anode currents have a wide spread; for all tubes the maximum value is 5.23 times larger than the minimum value. The MAPMT cross talk was measured for one of the central inputs. The maximum cross talk value is about 4.9%. The average cross talk for the nearest four neighboring channels is 3.9%, for the farther four 1%. To assure reproducibility and repeatability of the measurements a double reference method was used.
Detailed measurements of the wavelength shifting fiber response to a stable and reliable light source are presented. Particulars about materials, a double reference method, and measurement technique ...are included. The fibers studied were several hundred Kuraray, Y-11, multiclad, 1.2-mm outer diameter wavelength shifting fibers, each cut from a reel to about one meter length. The fibers were polished, mirrored, and the mirrors were UV epoxy protected. Each fiber passed quality control requirements before installation. About 94% of the fibers tested have a response within 1% of the overall mean
Radiation tests of Hamamatsu multi-pixel photon counters Blazey, G.; Colston, J.; Dyshkant, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2019, Letnik:
927, Številka:
C
Journal Article
Recenzirano
Odprti dostop
Results of radiation tests of Hamamatsu 2.0 × 2.0 mm2 through-silicon-via (S13360-2050VE) multi-pixel photon counters, or MPPCs, are presented (Hamamatsu, 0000). Distinct sets of eight MPPCs were ...exposed to four different 1 MeV neutron equivalent doses of 200 MeV protons. Measurements of the breakdown voltage, gain and noise rates at different bias overvoltages, photoelectron thresholds, and LED illumination levels were taken before and after irradiation. No significant deterioration in performance was observed for breakdown voltage, gain, and response. Noise rates increased significantly with irradiation. These studies were undertaken in the context of MPPC requirements for the Cosmic Ray Veto detector of the Mu2e experiment at the Fermi National Accelerator Laboratory.
Investigation of a solid-state photodetector Beznosko, D.; Blazey, G.; Chakraborty, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2005, Letnik:
545, Številka:
3
Journal Article
Recenzirano
We present results on the operation and performance characteristics of the MRS (metal/resistor/semiconductor) photodiode. These include measurements of threshold characteristics, noise frequency, ...dependence of signal amplitude on the applied voltage and temperature, and stability as a function of time and radiation dose. The single photoelectron separation for this photosensor is demonstrated with a light emitting diode. The response of the photodetector to light produced in a scintillator is studied with cosmic ray muons and a
106Ru source. In addition, fiber-sensor alignment issues were evaluated. The results are promising and illustrate the potential use of MRS as photosensors in high-energy physics detectors.
A neural network for software compensation was developed for the highly granular CALICE Analogue Hadronic Calorimeter (AHCAL). The neural network uses spatial and temporal event information from the ...AHCAL and energy information, which is expected to improve sensitivity to shower development and the neutron fraction of the hadron shower. The neural network method produced a depth-dependent energy weighting and a time-dependent threshold for enhancing energy deposits consistent with the timescale of evaporation neutrons. Additionally, it was observed to learn an energy-weighting indicative of longitudinal leakage correction. In addition, the method produced a linear detector response and outperformed a published control method regarding resolution for every particle energy studied.
We present various properties of the production of the X(3872) and ψ(2S) states based on 10.4 fb−1 collected by the D0 experiment in Tevatron pp collisions at √s = 1.96 TeV. For both states, we ...measure the nonprompt fraction fNP of the inclusive production rate due to decays of b-flavored hadrons. We find the fNP values systematically below those obtained at the LHC. The fNP fraction for ψ(2S) increases with transverse momentum, whereas for the X(3872) it is constant within large uncertainties, in agreement with the LHC results. The ratio of prompt to nonprompt ψ(2S) production, (1 − fNP)=fNP, decreases only slightly going from the Tevatron to the LHC, but for the X(3872), this ratio decreases by a factor of about 3. We test the soft-pion signature of the X(3872) modeled as a weakly bound charm-meson pair by studying the production of the X(3872) as a function of the kinetic energy of the X(3872) and the pion in the X(3872)π center-of-mass frame. For a subsample consistent with prompt production, the results are incompatible with a strong enhancement in the production of the X(3872) at the small kinetic energy of the X(3872) and the π in the X(3872)π center-of-mass frame expected for the X þ soft-pion production mechanism. For events consistent with being due to decays of b hadrons, there is no significant evidence for the soft-pion effect, but its presence at the level expected for the binding energy of 0.17 MeV and the momentum scale Λ ¼ M(π) is not ruled out.
The DO central track trigger Olsen, J.; Anderson, J.; Angstadt, R. ...
IEEE transactions on nuclear science,
2004-June, 2004-06-00, 20040601, Letnik:
51, Številka:
3
Journal Article
Recenzirano
Odprti dostop
An overview of the system architecture and algorithms used for the DO Central Track Trigger (CTT) in the Run 2 of the Fermilab Tevatron Proton-Antiproton Collider is presented. This system uses ...information from the newly commissioned Central Fiber Tracker and Preshower Detectors to generate Level 1 trigger decisions. It also generates lists of seed tracks and preshower clusters that are sent to the Level 1 Muon Trigger, L2 Silicon Track Trigger, and Central and Forward Preshower Level 2 preprocessors. The system consists of modular boards which utilize field-programmable gate arrays (FPGAs) to implement trigger algorithms. The system delivers trigger decisions every 132 ns, based on input data flowing at a maximum sustained rate of 475 gigabits per second. The first results of trigger efficiency studies are presented.
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