DigiCam - Fully Digital Compact Read-out and Trigger Electronics for the SST-1M Telescope proposed for the Cherenkov Telescope Array

The SST-1M is one of three prototype small-sized telescope designs proposed for the Cherenkov Telescope Array, and is built by a consortium of Polish and Swiss institutions. The SST-1M will operate with DigiCam - an innovative, compact camera with fully digital read-out and trigger electronics. A high level of integration will be achieved by massively deploying state-of-the-art multi-gigabit transmission channels, beginning from the ADC flash converters, through the internal data and trigger signals transmission over backplanes and cables, to the camera's server link. Such an approach makes it possible to design the camera to fit the size and weight requirements of the SST-1M exactly, and provide low power consumption, high reliability and long lifetime. The structure of the digital electronics will be presented, along with main physical building blocks and the internal architecture of FPGA functional subsystems.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

Software design for the control system for Small-Size Telescopes with single-mirror of the Cherenkov Telescope Array

The Small-Size Telescope with single-mirror (SST-1M) is a 4 m Davies-Cotton telescope and is among the proposed telescope designs for the Cherenkov Telescope Array (CTA). It is conceived to provide the high-energy ($>$ few TeV) coverage. The SST-1M contains proven technology for the telescope structure and innovative electronics and photosensors for the camera. Its design is meant to be simple, low-budget and easy-to-build industrially. Each device subsystem of an SST-1M telescope is made visible to CTA through a dedicated industrial standard server. The software is being developed in collaboration with the CTA Medium-Size Telescopes to ensure compatibility and uniformity of the array control. Early operations of the SST-1M prototype will be performed with a subset of the CTA central array control system based on the Alma Common Software (ACS). The triggered event data are time stamped, formatted and finally transmitted to the CTA data acquisition. The software system developed to control the devices of an SST-1M telescope is described, as well as the interface between the telescope abstraction to the CTA central control and the data acquisition system.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

Using muon rings for the optical throughput calibration of the SST-1M prototype for the Cherenkov Telescope Array

Imaging Atmospheric Cherenkov Telescopes (IACTs) are ground-based instruments devoted to the study of very high energy gamma-rays coming from space. The detection technique consists of observing images created by the Cherenkov light emitted when gamma rays, or more generally cosmic rays, propagate through the atmosphere. While in the case of protons or gamma-rays the images present a filled and more or less elongated shape, energetic muons penetrating the atmosphere are visualised as characteristic circular rings or arcs. A relatively simple analysis of the ring images allows the reconstruction of all the relevant parameters of the detected muons, such as the energy, the impact parameter, and the incoming direction, with the final aim to use them to calibrate the total optical throughput of the given IACT telescope. We present the results of preliminary studies on the use of images created by muons as optical throughput calibrators of the single mirror small size telescope prototype SST-1M proposed for the Cherenkov Telescope Array.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

Prototype of the SST-1M Telescope Structure for the Cherenkov Telescope Array

A single-mirror small-size (SST-1M) Davies-Cotton telescope with a dish diameter of 4 m has been built by a consortium of Polish and Swiss institutions as a prototype for one of the proposed small-size telescopes for the southern observatory of the Cherenkov Telescope Array (CTA). The design represents a very simple, reliable, and cheap solution. The mechanical structure prototype with its drive system is now being tested at the Institute of Nuclear Physics PAS in Krakow. Here we present the design of the prototype and results of the performance tests of the structure and the drive and control system.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

Description of the accuracy of conventional and double current supplied 4R mesh circuit as resistance converter in 2D measurements

Rozpatrzono zastosowania układu czterech rezystancji (4R) połączonych w oczko w pomiarach dwuparametrowych (2D) jako przetwornika różnych kombinacji przyrostów tych rezystancji na dwa napięcia wyjściowe, jako odchyłowego mostka sensorowego przy zasilaniu klasycznym, prądowym lub napięciowym oraz przy zasilaniu niekonwencjonalnym dwuprądowym - równolegle do ramion przeciwległych. Podano zracjonalizowane iloczynowe postacie funkcji rozwarciowych współczynników przetwarzania tych układów oraz wzory dla propagacji ich błędów przy dowolnych przyrostach rezystancji ramion układu z wyodrębnieniem składników dla stanu początkowego i dla funkcji przetwarzania. Jako przykład, przy obu rodzajach zasilania prądowego układu 4R o jednakowych rezystancjach początkowych, przedstawiono i porównano przebiegi funkcji błędów granicznych dla względnych zmian dwu sąsiednich rezystancji.The single mesh circuit of arbitrary variable four arm resistances (4R), as primary converter of different combinations of their increments to two output voltages is considered. This 4R circuit can be supplied conventionally from current or voltage source as the deflection sensor bridge or supplied unconventionally by two current sources parallel to opposite arms. Functions of circuit transfer coefficients in 2D measurements by both type of supply and input resistance in rationalized forms for the unloaded outputs are given. Their error propagation formulas and limit errors in rationalized double component forms for zero error and increment error are find. As the example, limit errors of 4R circuit of similar initial resistances and of two arbitrary changed adjacent arms as functions of related resistance increments for both types of current supply, are presented in figures and compared

Functions of limit errors and uncertainties of sensor bridges as resistance to voltage converters

Po krótkim wprowadzeniu w tabeli 1 podano funkcje rozwarciowych współczynników przetwarzania rezystancji na napięcie i ich zracjonalizowane postacie iloczynowe dla przetwornika w postaci mostka rezystancyjnego (4R) o zasilaniu prądowym lub napięciowym i dowolnych przyrostach rezystancji jego ramion. Przedstawiono dwa zaproponowane ujęcia błędów i niepewności: jednorodne, w wartościach względnych odniesionych do czułości początkowych i dwuskładnikowe – z wyodrębnieniem składników dla stanu początkowego i dla przyrostu funkcji przetwarzania. Rozpatrzono przetworniki rezystancji – mostki, o jednakowych rezystancjach początkowych i pięciu najczęściej stosowanych wariantach ich przyrostów. Przedstawiono charakterystyki ich rozwarciowych funkcji przetwarzania oraz błędów granicznych i niepewności standardowych przy zasilaniu prądowym i napięciowym. Dla wariantów mostka o liniowych funkcjach przetwarzania podano dwie uogólnione postacie błędów granicznych. Wskazano możliwości zastosowania obu opisów dokładności.After short introduction, in table 1 functions of transfer coefficients and their rationalized forms of the converter R/U as the unloaded four arms bridge of arbitrary variable arm resistances, supplied from current or voltage source, are given together with their error propagation formulas. Two types of description of their errors and uncertainties, i.e. related to initial sensitivities of functions of bridge transfer coefficients and their rationalized double component forms for zero and increments of these transfer function, are introduced. Metrological properties of the commonly used bridge of similar initial arm resistances in balance and five variants of their increments are discussed. Transfer coefficient, limited error (worse case) and standard uncertainty as functions of relative increments in broad range are shown for these variants. Generalized formulas for bridges of the linear transfer function are introduced. Both methods are found also as the universal solution for other parametric sensor circuits

Application of Double Current Bridge-Circuit for Simultaneous Measurements of Strain and Temperature

Opisano czterozaciskowy (4T) układ mostka rezystancyjnego zasilanego niekonwencjonalnie z dwóch źródeł prądowych i o dwu wyjściach z obu jego przekątnych, nazwany mostkiem dwuprądowym (2J). Podano napięcia wyjściowe niezrównoważonego mostka jako funkcje rezystancji jego gałęzi lub ich przyrostów od równowagi mostka w wartościach względnych. Przedstawiono przykład realizacji dwuparametrowego (2D) przetwornika do równoczesnego pomiaru odkształcenia i temperatury wykorzystującego ten mostek i omówiono wybrane wyniki pomiarów eksperymentalnej jego weryfikacji.A four-terminal (4T) bridge circuit unconventionally supplied by two current sources connected in parallel to opposite arms, named double current bridge (2J) is presented. It has two different outputs from both diagonals. The output voltages described as functions of arm resistances or their increments from bridge balance in relative units are given. Example of its application is proposed. Signals conditioning formulas of the two-parameter (2D) measurement - of strain and temperature are discussed in details. Some results of experimental verification of instrumetation circuit, designed for this bridge are shortly presented

Accuracy analysis of the 2D resistance-to-voltage converters for resistive sensors

The novelty of this work is the analysis of accuracy measures and its visualization especially for the simultaneous two parameter measurements. The parameters of the resistance-to-voltage converters, i.e. different types of DC circuits with arbitrary variable resistive sensors (of relative resistance increments), and their accuracy measures are discussed. Transfer coefficients, limited error (and also standard uncertainty) as functions of relative increments of resistance are shown in broad range for different types of supply and sensor configuration of the circuit of initial 2D converters

The calibration process and metrological analysis of a transducer used to measure two physical quantities

This article presents a way of calibration of an unconventional two-current circuit, named 2J+2R, which consists of two current sources and two referential resistors connected to the circuit mass. This bridge was used to measure the beam deflection and the temperature increase simultaneously with the use of a pair of metal strain gauges. This paper contains theoretical and corrected (after calibration) processing characteristics of the measurement circuit. Calibration coefficients of both inputs, responsible for measurement of the measured values in the places where the strain gauges are attached, were calculated. Moreover, the standard combined and expanded uncertainties of both calibration coefficients were calculated and an uncertainty budget was made