Abstract
Corryvreckan
is a versatile, highly configurable software with a modular structure designed to reconstruct and analyse test beam and laboratory data.
It caters to the needs of the test beam ...community by providing a flexible offline event building facility to combine detectors with different readout schemes, with or without trigger information, and includes the possibility to correlate data from multiple devices based on timestamps.
Hit timing information, available with high precision from an increasing number of detectors, can be used in clustering and tracking to reduce combinatorics.
Several algorithms, including an implementation of Millepede-II, are provided for offline alignment.
A graphical user interface enables direct monitoring of the reconstruction progress and can be employed for quasi-online monitoring during data taking.
This work introduces the
Corryvreckan
framework architecture and user interface, and provides a detailed overview of the event building algorithm.
The reconstruction and analysis capabilities are demonstrated with data recorded at the DESY II Test Beam Facility using the EUDAQ2 data acquisition framework with an EUDET-type beam telescope, a Timepix3 timing reference, a fine-pitch planar silicon sensor with CLICpix2 readout and the AIDA Trigger Logic Unit.
The individual steps of the reconstruction chain are presented in detail.
Allpix2 is a versatile, open-source simulation framework for silicon pixel detectors. Its goal is to ease the implementation of detailed simulations for both single sensors and more complex setups ...with multiple detectors. While originally created for silicon detectors in high-energy physics, it is capable of simulating a wide range of detector types for various application scenarios, through its interface to Geant4 to describe the interaction of particles with matter, and the different algorithms for charge transport and digitization. The simulation chain is arranged with the help of intuitive configuration files and an extensible system of modules, which implement the individual simulation steps. Detailed electric field maps imported from TCAD simulations can be used to precisely model the drift behavior of the charge carriers, bringing a new level of realism to the Monte Carlo simulation of particle detectors. Recently, Allpix2 has seen major improvements to its core framework to take full advantage of multi- and many-core processor architectures for simulating events fully parallel. Furthermore, new physics models such as charge carrier recombination in silicon have been introduced, further extending the application range. This contribution provides an overview of the framework and its components, highlighting the versatility and recent developments.
Abstract
Allpix
2
is a versatile, open-source simulation framework for silicon pixel detectors. Its goal is to ease the implementation of detailed simulations for both single sensors and more complex ...setups with multiple detectors. While originally created for silicon detectors in high-energy physics, it is capable of simulating a wide range of detector types for various application scenarios, through its interface to Geant4 to describe the interaction of particles with matter, and the different algorithms for charge transport and digitization. The simulation chain is arranged with the help of intuitive configuration files and an extensible system of modules, which implement the individual simulation steps. Detailed electric field maps imported from TCAD simulations can be used to precisely model the drift behavior of the charge carriers, bringing a new level of realism to the Monte Carlo simulation of particle detectors.
Recently, Allpix
2
has seen major improvements to its core framework to take full advantage of multi- and many-core processor architectures for simulating events fully parallel. Furthermore, new physics models such as charge carrier recombination in silicon have been introduced, further extending the application range. This contribution provides an overview of the framework and its components, highlighting the versatility and recent developments.
As part of an ongoing project on the phylogeny and taxonomy of Chenopodiaceae with emphasis on the evolution of photosynthetic pathways, we sequenced the nuclear ribosomal ITS region and two ...chloroplast DNA regions (atpB-rbcL and psbB-psbH) of 43 taxa belonging to subfamily Suaedoideae (Chenopodiaceae). Our sampling covered 41 of c. 82 known species and subspecies of Suaeda, beside several taxa not yet described, the monotypic genera Bienertia and Borszczowia as well as some representatives of Salicornioideae that served as outgroups. In addition, we carried out morphological and leaf anatomical studies on an extended sampling set, also including the monotypic genus Alexandra. Phylograms resulting from maximum parsimony analyses of separate and combined data sets share several common features. (1) Suaeda is monophyletic if Borszczowia is included. (2) The position of Bienertia is ambiguous, being sister to Suaeda in both chloroplast trees, but showing affinities to Salicornioideae in the ITS tree. (3) Suaeda deeply divides into two well-supported clades. One clade (Brezia clade) solely consists of the annual C3 species of sect. Brezia. The second clade (Suaeda clade) includes all other sections. (4) The subclades of the Suaeda clade are in general agreement with currently accepted sections. A reassessment of morphological and anatomical characters on the background of the molecular trees resulted in the recognition of pistil morphology and leaf type as key characters. All major molecular clades are precisely defined by characteristic combinations of pistil and leaf types. The following taxonomic conclusions are drawn: the status of Bienertieae Ulbr. is confirmed; Suaeda is subdivided into the new subgenera Brezia (Moq.) Freitag & Schütze and Suaeda; Borszczowia is recombined into Suaeda and given sectional rank; within Suaeda, sects. Brezia, Schanginia, Borszczowia, Suaeda, Physophora, Schoberia and Salsina are recognized with some changes in circumscription; Alexandra is maintained at generic level because of the lack of molecular data and its striking morphological differences from Suaeda. A conspectus of Suaedoideae containing recognized species and all supraspecific taxa is given. The molecular results confirm that C4 photosynthesis has evolved independently four times in the subfamily.
The DESY II test beam facility Diener, R.; Dreyling-Eschweiler, J.; Ehrlichmann, H. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2019, Letnik:
922
Journal Article
Recenzirano
Odprti dostop
DESY Hamburg operates a test beam facility with three independent beam lines at the DESY II synchrotron. It is world-wide one of very few facilities providing test beams in the GeV range. To this ...end, it offers electron/positron beams with user-selectable momenta from 1-6GeV/c. The available infrastructure for the users is unique, including a high field solenoidal magnet and permanently installed high-precision pixel beam telescopes. This publication gives a detailed description of the facility, the available infrastructure, and the simulated and measured performance.
An ever-increasing demand for high-performance silicon sensors requires complex sensor designs that are challenging to simulate and model. The combination of electrostatic finite element simulations ...with a transient Monte Carlo approach provides simultaneous access to precise sensor modelling and high statistics. The high simulation statistics enable the inclusion of Landau fluctuations and production of secondary particles, which offers a realistic simulation scenario. The transient simulation approach is an important tool to achieve an accurate time-resolved description of the sensor, which is crucial in the face of novel detector prototypes with increasingly precise timing capabilities. The simulated time resolution as a function of operating parameters as well as the full transient pulse can be monitored and assessed, which offers a new perspective for the optimisation and characterisation of silicon sensors.
In this paper, a combination of electrostatic finite-element simulations using 3D TCAD and transient Monte Carlo simulations with the Allpix2 framework are presented for a monolithic CMOS pixel sensor with a small collection electrode, that is characterised by a highly inhomogeneous, complex electric field. The results are compared to transient 3D TCAD simulations that offer a precise simulation of the transient behaviour but long computation times. Additionally, the simulations are benchmarked against test-beam data and good agreement is found for the performance parameters over a wide range of different operation conditions.
Allpix2: A modular simulation framework for silicon detectors Spannagel, S.; Wolters, K.; Hynds, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2018, Letnik:
901
Journal Article
Recenzirano
Odprti dostop
Allpix2 (read: Allpix Squared) is a generic, open-source software framework for the simulation of silicon pixel detectors. Its goal is to ease the implementation of detailed simulations for both ...single detectors and more complex setups such as beam telescopes from incident radiation to the digitised detector response. Predefined detector types can be automatically constructed from simple model files describing the detector parameters.
The simulation chain is arranged with the help of intuitive configuration files and an extensible system of modules, which implement separate simulation steps such as realistic charge carrier deposition with the Geant4 toolkit or propagation of charge carriers in silicon using a drift–diffusion model. Detailed electric field maps imported from TCAD simulations can be used to precisely model the drift behaviour of charge carriers within the silicon, bringing a new level of realism to Monte Carlo based simulations of particle detectors.
This paper provides an overview of the framework and a selection of different simulation modules, and presents a comparison of simulation results with test beam data recorded with hybrid pixel detectors. Emphasis is placed on the performance of the framework itself, using a first-principles simulation of the detectors without addressing secondary ASIC-specific effects.
EUDAQ is a generic data acquisition software developed for use in conjunction with common beam telescopes at charged particle beam lines. Providing high-precision reference tracks for performance ...studies of new sensors, beam telescopes are essential for the research and development towards future detectors for high-energy physics. As beam time is a highly limited resource, EUDAQ has been designed with reliability and ease-of-use in mind. It enables flexible integration of different independent devices under test via their specific data acquisition systems into a top-level framework. EUDAQ controls all components globally, handles the data flow centrally and synchronises and records the data streams. Over the past decade, EUDAQ has been deployed as part of a wide range of successful test beam campaigns and detector development applications.
Use of alternative initiator methionines in human invariant (Ii) chain mRNA results in the synthesis of two polypeptides, Iip33 and Iip31. After synthesis both isoforms are inserted into the ...endoplasmic reticulum (ER) as type II membrane proteins. Subsequently, Iip31 is transported out of the ER, guiding MHC class II to the endocytic pathway, whereas Iip33, which differs by only a 16 residue extension at the N‐terminus, becomes an ER resident. Mutagenesis of this extension showed that multiple arginines close to the N‐terminus were responsible for ER targeting. The minimal requirements of this targeting motif were found to be two arginines (RR) located at positions 2 and 3, 3 and 4 or 4 and 5 or split by a residue at positions 2 and 4 or 3 and 5. Transplanting an RR motif onto transferrin receptor demonstrated that this motif can target other type II membrane proteins to the ER. The characteristics of this RR motif are similar to the KK ER targeting motif for type I membrane proteins. Indeed, RR‐tagged transferrin receptor partially localized to the intermediate compartment, suggesting that like the KK motif, the RR motif directs the retrieval of membrane proteins to the ER via a retrograde transport pathway.
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