766 research outputs found
Demonstrator of the Belle II Online Tracking and Pixel Data Reduction on the High Level Trigger System
No full textWe present a computer-farm based data reduction
system for the pixel detector of the future Belle II experiment.
Belle II is a major upgrade of the Belle detector that is currently
ongoing in KEK (Tsukuba, Japan). Belle II will collect data
from SuperKEKB, an asymmetric e+e collider whose target
luminosity (81035 Hz=cm2) is a factor 40 larger than the present
world record held by its predecessor KEKB. The higher trigger
rate (10 kHz) and worse background conditions (3% average
occupancy on the pixel sensors) are a major challenge for both the
detectors and the Data Acquisition System (DAQ), in particular
for the inner part of the Belle II tracking system that consists of
two cylindrical layers of DEPFET pixels sensors (PXD) placed
just outside the beam pipe and very close to the Interaction
Point (IP). The long integration times of the PXD together
with the high background rate expected from pair production
occurring at the IP will lead to a large amount of data (more
than 20 GB/s) that must be reduced by at least a factor 10 to
satisfy the constraints coming from the available storage space
and bandwidth. A large amount of the background hits can be
rejected by defining a set of Region Of Interest (ROI) on the
PXD sensors and then recording just the data from the pixels
inside the ROI. The ROIs are defined on an event by event basis
by extrapolating back onto the PXD the charged tracks detected
in the outer silicon tracker (a 4 layer double-sided silicon strip
detector) and reconstructed online in real time. A demonstrator
of this architecture was under beam test earlier this year in
DESY (Hamburg, Germany). The demonstrator was operated
in an electron beam whose momentum was in the 2 - 6 GeV/c
range with a typical trigger rate of a few kHz in a magnetic field
of strength up to 1T. The demonstrator consists of one PXD
sensor and 4 SVD sensors arranged in a 5 layers configuration
mimicking the Belle II vertex detector. The detector readout was
a scaled down version of the full Belle II DAQ + High Level
Trigger (HLT) chain. The demonstrator was used to detect the
particles, reconstruct in real time the trajectories, identify the
ROIs on the PXD plane and record the PXD data within. In this
contribution, we describe the requirements and the architecture
of the final system together with the results obtained with the
demonstrator
Realizace komunikačního profilu a uživatelského rozhraní pro generátor síťového provozu
No full textThis diploma thesis deals with the design and implementation of a communication profile and user interface for already created software core of the network traffic generator. Author introduces the reader to possibilities of creating user interfaces in programming language Java, including a brief evaluation of them. Further, the available low-level tools for network traffic generation are analyzed. Based on the requirements specification is then designed and implemented user interface of the generator, which allows you to manage communication profiles and run individual tests over them. Finally, the project is economically evaluated and future development trends of the application are proposed
The new and complete Belle II DEPFET pixel detector: Commissioning and previous operational experience
No full text
Commissioning and performance of the Belle II pixel detector
No full texthttp://dx.doi.org/10.13039/501100001823 Ministerstvo Školství, Mládeže a Tělovýchovyhttp://dx.doi.org/10.13039/501100002347 Bundesministerium für Bildung und Forschunghttp://dx.doi.org/10.13039/501100001691 Japan Society for the Promotion of Sciencehttp://dx.doi.org/10.13039/501100003329 Ministerio de Economía y Competitividadhttp://dx.doi.org/10.13039/501100001700 Ministry of Education, Culture, Sports, Science and Technolog
Issue of “special ovens” in ancient Zvenyhorod on Bilka river
No full textThe article is dedicated to analyses of results of excavations on the territory of western part of hill-fort in Zvenyhorod (Pustomyty district, L’viv region) – western area of outer part of annalistic city. Investigations were carried out in 1954–1969 (with interruptions), when complex, which consists of 44 ovens was discovered. But this material is still not published. Series of facts, connected with stratigraphy of objects, their constructional peculiarities and character of finds were elucidated on the base of research of scientific reports. Detail analyses of this data allow the author to present some questions about verification of dating, chronology and functions of discovered objects. These issues are very important for explorations of general character of constructional structure of the city
Issue of “special ovens” in ancient Zvenyhorod on Bilka river
No full textThe article is dedicated to analyses of results of excavations on the territory of western part of hill-fort in Zvenyhorod (Pustomyty district, L’viv region) – western area of outer part of annalistic city. Investigations were carried out in 1954–1969 (with interruptions), when complex, which consists of 44 ovens was discovered. But this material is still not published. Series of facts, connected with stratigraphy of objects, their constructional peculiarities and character of finds were elucidated on the base of research of scientific reports. Detail analyses of this data allow the author to present some questions about verification of dating, chronology and functions of discovered objects. These issues are very important for explorations of general character of constructional structure of the city
The simulation library of the Belle II software system
No full textSuperKEKB, the next generation B factory, has been constructed in Japan as an upgrade of KEKB. This brand new e+ e- collider is expected to deliver a very large data set for the Belle II experiment, which will be 50 times larger than the previous Belle sample. Both the triggered physics event rate and the background event rate will be increased by at least 10 times than the previous ones, and will create a challenging data taking environment for the Belle II detector. The software system of the Belle II experiment is designed to execute this ambitious plan. A full detector simulation library, which is a part of the Belle II software system, is created based on Geant4 and has been tested thoroughly. Recently the library has been upgraded with Geant4 version 10.1. The library is behaving as expected and it is utilized actively in producing Monte Carlo data sets for various studies. In this paper, we will explain the structure of the simulation library and the various interfaces to other packages including geometry and beam background simulation
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