37 research outputs found
Level Zero Trigger Processor for the NA62 experiment
The NA62 experiment is designed to measure the ultra-rare decay branching ratio with a precision of 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.Comment: 15 page
Fast algorithm for real-time rings reconstruction
The GAP project is dedicated to study the application of GPU in several contexts in which
real-time response is important to take decisions. The definition of real-time depends on
the application under study, ranging from answer time of ÎŒs up to several hours in case
of very computing intensive task. During this conference we presented our work in low
level triggers [1] [2] and high level triggers [3] in high energy physics experiments, and
specific application for nuclear magnetic resonance (NMR) [4] [5] and cone-beam CT [6].
Apart from the study of dedicated solution to decrease the latency due to data transport
and preparation, the computing algorithms play an essential role in any GPU application.
In this contribution, we show an original algorithm developed for triggers application, to
accelerate the ring reconstruction in RICH detector when it is not possible to have seeds
for reconstruction from external trackers
Italian natural history museums on the verge of collapse?
The Italian natural history museums are facing a critical situation, due to the progressive loss of scientific relevance, decreasing economic investments, and scarcity of personnel. This is extremely alarming, especially for ensuring the long-term preservation of the precious collections they host. Moreover, a commitment in fieldwork to increase scientific collections and concurrent taxonomic research are rarely considered priorities, while most of the activities are addressed to public events with political payoffs, such as exhibits, didactic meetings, expositions, and talks. This is possibly due to the absence of a national museum that would have better steered research activities and overall concepts for collection management. We here propose that Italian natural history museums collaborate to instate a âmetamuseumâ, by establishing a reciprocal interaction network aimed at sharing budgetary and technical resources, which would assure better coordination of common long-term goals and scientific activities
Graphics processors in HEP low-level trigger systems
Usage of Graphics Processing Units (GPUs) in the so called general-purpose computing is emerging as an effective approach in several fields of science, although so far applications have been employing GPUs typically for offline computations. Taking into account the steady performance increase of GPU architectures in terms of computing power and I/O capacity, the real-time applications of these devices can thrive in high-energy physics data acquisition and trigger systems. We will examine the use of online parallel computing on GPUs for the synchronous low-level trigger, focusing on tests performed on the trigger system of the CERN NA62 experiment. To successfully integrate GPUs in such an online environment, latencies of all components need analysing, networking being the most critical. To keep it under control, we envisioned NaNet, an FPGA-based PCIe Network Interface Card (NIC) enabling GPUDirect connection. Furthermore, it is assessed how specific trigger algorithms can be parallelized and thus benefit from a GPU implementation, in terms of increased execution speed. Such improvements are particularly relevant for the foreseen Large Hadron Collider (LHC) luminosity upgrade where highly selective algorithms will be essential to maintain sustainable trigger rates with very high pileup
Graphics Processors in HEP Low-Level Trigger Systems
Usage of Graphics Processing Units (GPUs) in the so called general-purpose computing is emerging as an effective approach in several fields of science, although so far applications have been employing GPUs typically for offline computations. Taking into account the steady performance increase of GPU architectures in terms of computing power and I/O capacity, the real-time applications of these devices can thrive in high-energy physics data acquisition and trigger systems. We will examine the use of online parallel computing on GPUs for the synchronous low-level trigger, focusing on tests performed on the trigger system of the CERN NA62 experiment. To successfully integrate GPUs in such an online environment, latencies of all components need analysing, networking being the most critical. To keep it under control, we envisioned NaNet, an FPGA-based PCIe Network Interface Card (NIC) enabling GPUDirect connection. Furthermore, it is assessed how specific trigger algorithms can be parallelized and thus benefit from a GPU implementation, in terms of increased execution speed. Such improvements are particularly relevant for the foreseen Large Hadron Collider (LHC) luminosity upgrade where highly selective algorithms will be essential to maintain sustainable trigger rates with very high pileup
Operation of the CGEM Detector
A ten years extension of the data taking of BESIII experiment, recently approved, motivated an upgrade program both for the leptonic collider BEPCII and for some of the sub-detectors of the spectrometer. BESIII is a multipurpose spectrometer optimized for physics in the charm-Ï energy region. In particular, the current inner drift chamber is suffering from aging and the proposal is to replace it with a detector based on Cylindrical Gas Electron Multiplier (CGEM) technology to improve both the secondary vertex reconstruction and the radiation tolerance. The CGEM Inner Tracker will be composed of three coaxial layers of cylindrical triple GEMs, operating in an Ar + iC4H10 (90:10) gas mixture with field and gain optimized to maximize the spatial resolution. The new detector is readout with innovative TIGER electronics produced in 110 nm CMOS technology. A cosmic telescope instrumented with two out of three layers is in operation in Beijing since January 2020, remotely controlled by Italian groups due to the pandemic situation. A dedicated readout chain was developed for data acquisition. In this paper, the general status of the project will be presented with a particular focus on the preliminary results from the cosmic data taking and future plans
GPUs for online processing in low-level trigger systems
We describe a pilot project for the use of GPUs (Graphics Processing Units) in online triggering applications for high energy physics experiments. General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to the specific strengths of such devices as accelerator in offline computation. With the steady reduction of GPU latencies, and the increase in link and memory throughput, the use of such devices for real-time applications in high-energy physics data acquisition and trigger systems is becoming ripe. We will discuss in details the use of online parallel computing on GPU for synchronous low level trigger systems. We will show the results of two solutions to reduce the data transmission latency: the first based on fast capture special driver and the second based on direct GPU communication using NaNet, a multi-standard, FPGA-based, low-latency, PCIe network interface card with GPUDirect capabilities. We will present preliminary results on a first field test in the CERN NA62 experiment. This study is done in the framework of GAP (GPU Application Project), a wider project intended to study the use of GPUs in real-time applications