11 research outputs found
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
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
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
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
Observation of large scale precursor correlations between cosmic rays and earthquakes with a periodicity similar to the solar cycle
The search for correlations between secondary cosmic ray detection rates and seismic effects has long been a
subject of investigation motivated by the hope of identifying a new precursor type that could feed a global early
warning system against earthquakes. Here we show for the first time that the average variation of the cosmic ray
detection rates correlates with the global seismic activity to be observed with a time lag of approximately two
weeks, and that the significance of the effect varies with a periodicity resembling the undecenal solar cycle, with
a shift in phase of around three years, exceeding 6 σ at local maxima. The precursor characteristics of the
observed correlations point to a pioneer perspective of an early warning system against earthquakes
Camera calibration strategy of the SST-1M prototype of the Cherenokov Telescope Array
The SST-1M telescope is one of the prototypes under construction proposed to
be part of the future Cherenkov Telescope Array. It uses a standard
Davis-Cotton design for the optics and telescope structure, with a dish
diameter of 4 meters and a large field-of-view of 9 degrees.
The innovative camera design is composed of a photo-detection plane with 1296
pixels including entrance window, light concentrators, Silicon Photomultipliers
(SiPMs), and pre-amplifier stages together with a fully digital readout and
trigger electronics, DigiCam.
In this contribution we give a general description of the analysis chain
designed for the SST-1M prototype. In particular we focus on the calibration
strategy used to convert the SiPM signals registered by DigiCam to the
quantities needed for Cherenkov image analysis. The calibration is based on an
online feedback system to stabilize the gain of the SiPMs, as well as dedicated
events (dark count, pedestal, and light flasher events) to be taken during the
normal operation of the prototype.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
Front-end and slow control electronics for large area SiPMs used for the single mirror Small Size Telescope (SST-1M) of the Cherenkov Telescope Array (CTA)
The single mirror Small Size Telescope (SST-1M) project proposes a design among others for the smallest type of telescopes (SST), that will compose the south observatory of the Cherenkov Telescope Array (CTA). The SST camera collecting the Cherenkov light resulting from very high energy gamma-ray interactions in the atmosphere proposes to use Silicon PhotoMultipliers (SiPM). The SST-1M design has led to the use of unique pixel shape and size that required a dedicated development by the University of Geneva and Hamamatsu. An active surface of 3c94 mm2 and a resulting total capacitance of 3c3.4 nF combined with the stringent requirements of the CTA project on timing and charge resolution have led the University of Geneva to develop a custom preamplifier stage and slow-control system. The design and performance of the tailor made preamplifier stage and of the slow control electronics will be briefly described. The bias circuit of the sensor contains a resistor meant to prevent the sensor from drawing high current. However this resistor also introduces a voltage drop at the sensor input impacting the stability of its operation. A model has been developed in order to derive the parameters needed to account for it at the data analysis level. A solution based on the SST-1M front-end and digital readout is proposed to compensate for the voltage drop at the sensor cathode
The front-end electronics and slow control of large area SiPM for the SST-1M camera developed for the CTA experiment
The small size telescope projects for the Cherenkov Telescope Array
The small size telescopes (SSTs), spread over an area of several square km,
dominate the CTA sensitivity in the photon energy range from a few TeV to over
100 TeV, enabling for the detailed exploration of the very high energy
gamma-ray sky. The proposed telescopes are innovative designs providing a wide
field of view. Two of them, the ASTRI (Astrophysics con Specchi a Tecnologia
Replicante Italiana) and the GCT (Gamma-ray Cherenkov Telescope) telescopes,
are based on dual mirror Schwarzschild-Couder optics, with primary mirror
diameters of 4 m. The third, SST-1M, is a Davies-Cotton design with a 4 m
diameter mirror. Progress with the construction and testing of prototypes of
these telescopes is presented. The SST cameras use silicon photomultipliers,
with preamplifier and readout/trigger electronics designed to optimize the
performance of these sensors for (atmospheric) Cherenkov light. The status of
the camera developments is discussed. The SST sub-array will consist of about
70 telescopes at the CTA southern site. Current plans for the implementation of
the array are presented
Ellsworth American : January 19, 1893
The single mirror small-size telescope (SST-1M) is one of the telescope projects being proposed for the Cherenkov Telescope Array observatory by a sub-consortium of Polish and Swiss institutions. The SST-1M prototype structure is currently being constructed at the Institute of Nuclear Physics in Cracow, Poland, while the camera will be assembled at the University of Geneva, Switzerland. This prototype enables measurements of parameters having a decisive influence on the telescope performance. We present results of numerical simulations of the SST-1M performance based on such measurements. The telescope effective area, the expected trigger rates and the optical point spread function are calculated