We have observed a significant enhancement in the energy deposition by 25–
100
GeV
photons in a
1
cm
thick tungsten crystal oriented along its
⟨
111
⟩
lattice axes. At
100
GeV
, this enhancement, ...with respect to the value observed without axial alignment, is more than twofold. This effect, together with the measured huge increase in secondary particle generation is ascribed to the acceleration of the electromagnetic shower development by the strong axial electric field. The experimental results have been critically compared with a newly developed Monte Carlo adapted for use with crystals of multi-
X
0
thickness. The results presented in this paper may prove to be of significant interest for the development of high-performance photon absorbers and highly compact electromagnetic calorimeters and beam dumps for use at the energy and intensity frontiers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The integrated low-level trigger and data acquisition (TDAQ) system of the NA62 experiment at CERN is described. The requirements of a large and fast data reduction in a high-rate environment for a ...medium-scale, distributed ensemble of many different sub-detectors led to the concept of a fully digital integrated system with good scaling capabilities. The NA62 TDAQ system is rather unique in allowing full flexibility on this scale, allowing in principle any information available from the detector to be used for triggering. The design concept, implementation and performances from the first years of running are illustrated.
The NA62 experiment is designed to measure the ultra-rare decay K+arrowπ+ν branching ratio with a precision of ∼10% at the CERN Super Proton Synchrotron (SPS). The trigger system of NA62 consists in ...three different levels designed to select events of physics interest in a high beam rate environment. The L0 Trigger Processor (L0TP) is the lowest level system of the trigger chain. It is hardware implemented using programmable logic. The architecture of the NA62 L0TP system is a new approach compared to existing systems used in high-energy physics experiments. It is fully digital, based on a standard gigabit Ethernet communication between detectors and the L0TP Board. The L0TP Board is a commercial development board, mounting a programmable logic device (FPGA). The primitives generated by sub-detectors are sent asynchronously using the UDP protocol to the L0TP during the entire beam spill period. The L0TP realigns in time the primitives coming from seven different sources and performs a data selection based on the characteristics of the event such as energy, multiplicity and topology of hits in the sub-detectors. It guarantees a maximum latency of 1 ms. The maximum input rate is about 10 MHz for each sub-detector, while the design maximum output trigger rate is 1 MHz. A description of the trigger algorithm is presented here.
Abstract
The readout electronics for the CMS electromagnetic calorimeter is undergoing a re-design in order to cope with the LHC ugrade. In particular, a fourfold increase in the sampling frequency ...(from 40 to 160 MS/s) is required. Therefore a new readout ASIC has been developed. The ASIC, named LiTE-DTU, is designed in a CMOS 65 nm technology. The LiTE-DTU embeds two 12 bit, 160 MS/s ADCs, a time window based sample selection, lossless data compression and 1.28 Gb/s serialization. An on-chip PLL provides the 1.28 GHz clock required by the ADCs and the serializers from the 160 MHz clock.
An approach based on hydraulic simulation and machine learning is presented, aimed at improving leakage management via analytical leak localization and reducing time and costs for investigation and ...rehabilitation of the Water Distribution Network. Hydraulic simulation is used to run different leakage scenarios by introducing a leak on each pipe, in turn, and varying its severity. The approach has been validated on two WDNs: a Pressure Management Zone in Milan (Italy) and a District Metered Area in Timisoara (Romania), the two pilots of the EU-FP7-ICT project ICeWater, obtaining a high reliability (>90%) in localizing a wide set of simulated leaks.
Abstract
A new FPGA-based low-level trigger processor has been installed at the NA62 experiment. It is intended to extend the features of its predecessor due to a faster interconnection technology ...and additional logic resources available on the new platform. With the aim of improving trigger selectivity and exploring new architectures for complex trigger computation, a GPU system has been developed and a neural network on FPGA is in progress. They both process data streams from the ring imaging Cherenkov detector of the experiment to extract in real time high level features for the trigger logic. Description of the systems, latest developments and design flows are reported in this paper.
The Level 0 Trigger Processor for the NA62 experiment Chiozzi, S.; Gamberini, E.; Gianoli, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2016, Letnik:
824
Journal Article
Recenzirano
Odprti dostop
In the NA62 experiment at CERN, the intense flux of particles requires a high-performance trigger for the data acquisition system. A Level 0 Trigger Processor (L0TP) was realized, performing the ...event selection based on trigger primitives coming from sub-detectors and reducing the trigger rate from 10 to 1MHz. The L0TP is based on a commercial FPGA device and has been implemented in two different solutions. The performance of the two systems are highlighted and compared.
Abstract
The NA62 experiment at the CERN SPS aims to measure the branching ratio of the very rare kaon decay
K
+
→
π
+
ν
ν
¯
. The Calorimetric Level 0 Trigger identifies clusters in the ...electromagnetic and hadronic calorimeters. Along with the trigger data sent to the L0 Trigger Processor, readout data is collected to be sent to the L1 software trigger. In this work we present the novel implementation of the readout data collection and forwarding system in the multiple layers of the calorimetric trigger structure. We will also present the commissioning of the system and the performance evaluation on current data taking.
The NA62 experiment at the CERN SPS reports the first search for K+→π+νν¯ using the decay-in-flight technique, based on a sample of 1.21×1011K+ decays collected in 2016. The single event sensitivity ...is 3.15×10−10, corresponding to 0.267 Standard Model events. One signal candidate is observed while the expected background is 0.152 events. This leads to an upper limit of 14×10−10 on the K+→π+νν¯ branching ratio at 95% CL.
In the NA62 experiment at CERN-SPS the communication between detectors and the Lowest Level (L0) trigger processor is performed via Ethernet packets, using the UDP protocol. The L0 Trigger Processor ...handles the signals from sub-detectors that take part to the trigger generation. In order to choose the best solution for its realization, two different approaches have been implemented. The first approach is fully based on a FPGA device while the second one joins an off-the-shelf PC to the FPGA. The performance of the two systems will be discussed and compared.
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