The Muon g-2 experiment at Fermilab will measure the muon anomalous magnetic moment <inline-formula> <tex-math notation="LaTeX">a=(g-2)/2 </tex-math></inline-formula> to an unprecedented precision of ...0.14 parts per million (ppm). To this aim, a calibration system made by a laser source and light distribution will provide short light pulses directly into each crystal of the 24 calorimeters to measure energy and arrival time of the decay positrons. Each calorimeter is composed of a <inline-formula> <tex-math notation="LaTeX">6\times 9 </tex-math></inline-formula> matrix of <inline-formula> <tex-math notation="LaTeX">PbF_{2} </tex-math></inline-formula> crystals where each crystal is read by a silicon photomultiplier. Continuous monitoring and state-of-the-art calibration are required in order to control the detector response. The calibration light pulses are monitored, both at the laser output (source monitor) and at the end of the distribution system (local monitor), before delivery to the calorimeters. For example, the light pulses are read by specific photodetectors, whose signals are digitized by electronics designed to match the experimental requirements. All readout electronics boards are hosted in a crate where the controller manages the complete data collection, operates as an event builder and transfers data to the online farm system through a gigabit Ethernet connection. This data acquisition (DAQ) system is designed around a custom protocol and hardware to achieve high data transfer rate and event-building capability without software overhead. In this paper, after a general outline of this DAQ system, we describe in detail the main features of controller.
KM3NeT is a network of submarine Cherenkov neutrino telescopes under construction at two different sites in the Mediterranean Sea. ARCA, near Sicily in Italy, is optimised for the detection of cosmic ...neutrinos while ORCA, near Toulon in France, is optimized for atmospheric neutrinos. ARCA and ORCA are both arrays of thousands of optical sensors (Digital Optical Modules - DOMs), each consisting of 31 small photomultipliers (PMTs) housed inside a glass sphere, which detect the Cherenkov light produced by the secondary particles generated in the neutrino interactions. 18 DOMs are arranged on flexible strings, referred to as vertical Detection Units (DUs), anchored to the sea floor. Once completed, ARCA and ORCA will consist of 230 and 115 DUs, respectively. Each DOM of a string communicates at a dedicated wavelength to the shore station via a network of optical fibers transmitting optical and acoustic signal information as well as orientation information. Before the deployment, each DU is tested and calibrated in a dark room. The test bench is equipped with a full data acquisition system for communication, data processing, and time synchronisation. Several steps are needed to accomplish the DU calibration, including the High-Voltage (HV) tuning of the PMTs, checking of the acoustic receivers and calibration light sources in the DOM, and time calibration using laser signals distributed to all DOMs. Here, we describe the DU test and calibration facility at the CAPACITY laboratory (Campania AstroPArtiCle InfrastrucTure facilitY) in Caserta, focusing on the functional tests and calibrations performed at the end of the DU integration.
CH3NH3PbI3 perovskite solar cells with a mesoporous TiO2 layer and spiro-MeOTAD as a hole transport layer (HTL) with three different CH3NH3I concentrations (0.032 M, 0.044 M and 0.063 M) were ...investigated. Strong variations in crystal size and morphology resulting in diversified cell efficiencies (9.2%, 16.9% and 12.3%, respectively) were observed. The physical origin of this behaviour was analysed by detailed characterization combining current-voltage curves with photo- and electroluminescence (PL and EL) imaging as well as light beam induced current measurements (LBIC). It was found that the most efficient cell shows the highest luminescence and the least efficient cell is most strongly limited by non-radiative recombination. Crystal size, morphology and distribution in the capping layer and in the porous scaffold strongly affect the non-radiative recombination. Moreover, the very non-uniform crystal structure with multiple facets, as evidenced by SEM images of the 0.032 M device, suggests the creation of a large number of grain boundaries and crystal dislocations. These defects give rise to increased trap-assisted non-radiative recombination as is confirmed by high-resolution μ-PL images. The different imaging techniques used in this study prove to be well-suited to spatially investigate and thus correlate the crystal morphology of the perovskite layer with the electrical and radiative properties of the solar cells and thus with their performance.
The monitoring system of the ARGO-YBJ data acquisition Mastroianni, S.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Volume:
617, Issue:
1
Journal Article
Peer reviewed
The ARGO-YBJ detector has been completely installed at the YangBaJing High Altitude Cosmic Ray Observatory (Tibet, China), at 4300
m a.s.l., and is taking data with a trigger rate of about 4
kHz and ...a dead time of about 4%. The ARGO-YBJ Data Acquisition System is based on a two-layer readout architecture implementing an event-driven data collection. In order to sustain a high data throughput and have a good readout efficiency or keep the dead time as low as possible, the decoupling FIFOs have been housed on the data packet processing modules. In this paper, the hardware solution to monitor the DAQ system and to track in real-time anomalous data transfers is presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
An integrated volatile organic toxicants sensor with a Bluetooth device interface has been developed. The device is based on novel tuning fork sensor platform along with a wireless ...communication/interface technology taken in an integrated system approach. It features high sensitivity and selectivity. The sensitivity and selectivity are accomplished through the use of novel tuning fork sensor modified by design (molecularly imprinted) polymers and selective filtering. Experiments have shown that the device can detect toxic volatile organic compounds (VOCs) under high concentrations of common interferents from flavors and fragrances. Applications of the device for detection of BTEX in real-world situations such as outdoor and gas station VOCs have also been demonstrated. All these features make the device a promising candidate to be deployed in real-world applications, particularly in environmental health and air pollution studies.
Time calibration is a crucial item for a shower array performance as it uses the time of flight method to reconstruct the arrival direction of the primary particle. This paper presents a software ...time calibration algorithm exploiting the continuous detector feature and based on the assumption of locally flat shower front; accordingly, taken a small portion of the detector (tens of m 2 ), a simple time-position fit of the arriving particles provides the time calibration constants of that part of detector. In a second step, the time offsets among the different portions are measured and the complete detector calibration is obtained. The implementation of this algorithm in an online environment like the ARGO-YBJ data acquisition system has been studied. The results of this investigation are reported and discussed.
Laser calibration facilities play a key role in the study and characterization of detectors like electromagnetic or hadronic calorimeters. They can be operated both during physics data taking and off ...runs. Typically, these facilities are based on a laser source which delivers light to each detector element via a light distribution system. The laser control (LC) system typically manages the interface between the experiment and the laser source, allowing the generation of light pulses according to specific needs such as detector calibration, study of detector performance in running conditions, and evaluation of data acquisition performance. Any specific implementation depends on hardware features. As an example, light pulses could be generated according to a physics distribution during physics runs or real data taking. In this case, light pulses should be generated according to a pattern that follows a programmable function and changes on a statistical base event by event. In this paper, we present a LC system for calibration of a calorimeter. It is a custom solution based on a hybrid platform hosting a field-programmable gate array and an ARM processor. We present the system architecture and the performances of a preliminary implementation. This system, in a more specific and specialized version, will be used in the Muon g-2 experiment (E989) at Fermilab.
The ARGO-YBJ experiment has been in stable data taking since November 2007 till February 2013 at the YangBaJing Cosmic Ray Laboratory (Tibet, P.R. China, 4300 m a.s.l.). Its main fields of research ...include gamma-ray astronomy with an energy threshold of a few hundreds GeV and Cosmic Ray physics up to PeV energies. The ARGO-YBJ detector consists of a single layer of RPCs operated in streamer mode, housed in a large building of about 11,000 m 2 . The signals from each RPC are picked up by 80 readout strips 61.8 cm long and 6.75 cm wide (23 strips/m 2 ) that allow the shower front reconstruction with a high space-time resolution. In order to fully investigate the PeV region, where the readout by strips saturates, an analog readout has been implemented by instrumenting each RPC with two large size electrodes of dimensions 1.23 × 1.39 m 2 . Since December 2009 the RPC charge readout has been in operation on the entire central carpet (about 5800 m 2 ). The ARGO-YBJ detector equipped with the analog readout is able to measure the particle density from tens to many thousands of particles per m 2 . Here we describe in detail the analog readout of RPCs in ARGO-YBJ and discuss the performance of the system that implements it.
Digitally-controlled delay lines (DCDLs) play a key role in timing distribution for trigger and data acquisition systems (TDAQ) of high energy Physics (HEP), where it is often necessary to add an ...open-loop fine-grained programmable phase delay to distributed clocks and/or data lines. In this work, we present the performance of DCDLs implemented according to an all-digital novel architecture. The architecture is completely technology-independent, it is described by means of a hardware description language and it can be placed and routed with automatic tools. Our solution is aimed at being used as a synthesizable block in FPGAs, as a proof-of-concept we implemented a prototype in a Xilinx Kintex-7 FPGA. We discuss the measured performance of the implemented delay line in terms of delay range, resolution and linearity. The logic utilization of the delay lines is also presented in the view of a scalable implementation.
We propose a unconventional calorimetry approach. The method is based on idea used for the first time in the energy determination of extensive air showers (EAS) at very high energy (>100 TeV). It has ...some peculiar characteristics which can be summarized in the following two points: a) measurement of the shower energy by means of a single sampling; b) measurement of the lateral density distribution of charged particles around the shower axis. We studied the validation of this measurement technique to lower energies (100 GeV–10 TeV) by MC calculation.
