We present the development of readout electronics and artificial-intelligence-based particle-identification methods for the SoLID Cherenkov detectors at Jefferson Lab. To operate in the high-rate, high-background SoLID environment, we designed a MAROC sum readout system for multianode photomultiplier tubes that provides simultaneous pixel, quadrant-sum, and total-sum signals. Bench studies show that the system can sustain rates at or above those expected for SoLID while maintaining acceptable pedestal behavior and signal linearity. Using realistic Geant4 simulations for the heavy-gas Cherenkov detector, we then investigate π/K separation with beam-related background. A simple photoelectron-counting cut is insufficient under these conditions, whereas multilayer perceptron models trained on PMT, quad, and pixel readout data perform substantially better. The quad and pixel readout schemes achieve pion and kaon efficiencies above 90% and clearly outperform PMT-only readout. These results demonstrate that the combination of high-rate MAROC sum electronics and AIML-based pattern recognition provides a practical path toward robust SoLID Cherenkov PID.

With the exponential growth in the volume and complexity of data generated at high-energy physics and nuclear physics research facilities, there is an imperative demand for innovative strategies to process this data in real or near-real-time. Given the surge in the requirement for high-performance computing, it becomes pivotal to reassess the adaptability of current data processing architectures in integrating new technologies and managing streaming data. This paper introduces the ERSAP framework, a modern solution that synergizes flow-based programming with the reactive actor model, paving the way for distributed, reactive, and high performance in data stream processing applications. Additionally, we unveil a novel algorithm focused on time-based clustering and event identification in data streams. The efficacy of this approach is further exemplified through the data-stream processing outcomes obtained from the recent beam tests of the EIC prototype calorimeter at DESY.

The ALERT-TOF detector (AtoF), to be installed in CLAS12 at Jefferson Lab, aims at detecting low momentum recoiling ions through scintillator coupled SiPM-generated pulses with excellent time resolution. The experimental capability and systematics can be greatly enhanced by the availability of waveform data from the scintillation process, especially during the high luminosity experimental configuration. For this reason, we developed a novel readout board using Nalu Scientific custom digitizing asics (ASoCs) that is capable of acquiring waveform data at ~2.2Gsps or more from 48 independent channels. The board is currently under testing and it is expected to be incorporated in the experiment in the near future.

Positron emission tomography (PET) is a radionuclide functional diagnostic imaging technique for medical applications such as cancer diagnosis and drug development. Jefferson Lab is developing PET instrumentation using a novel data acquisition system (DAQ) readout methodology referred to as streaming readout (SRO). The SRO-based approach transitions PET DAQ systems from traditional dedicated "triggered" systems to more versatile "triggerless" systems. In this new configuration, the SRO-enabled PET detector modules are interconnected using Ethernet with synchronized external timing circuitry. The SRO-PET system implementation is entirely software-based, encompassing detector calibrations and coincident event sorting. The adoption of SRO technology in PET instrumentation has the potential to simplify system installation and enhance key performance indices, especially for whole-body and total-body PET applications.

This article presents a framework based on a flow-based programming (FBP) paradigm to design data-stream processing applications for Nuclear Physics (NP). The developed framework encourages a functional decomposition of the overall data-processing application into small monofunctional artifacts that are easy to understand, develop, and debug. The fact that these artifacts (actors) are programmatically independent means that they can be scaled and optimized independently, which is difficult for monolithic application components. One of the advantages of this approach is fault tolerance, where independent actors can come and go in the data stream without stopping or crashing the entire application. Because actors are loosely coupled and data carries context, they can run in heterogeneous environments and utilize wide-ranging accelerators. This article describes the main design concepts of this framework, presenting a proof-of-concept application and the results of processing on-beam calorimeter streaming data.

The CLAS12 deep-inelastic scattering experiment at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Lab conjugates luminosity and wide acceptance to study the 3D nucleon structure in the yet poorly explored valence region, and to perform precision measurements in hadron spectroscopy. A large area ring-imaging Cherenkov detector has been designed to achieve the required hadron identification in the momentum range from 3 GeV/c to 8 GeV/c, with the kaon rate about one order of magnitude lower than the rate of pions and protons. The adopted solution comprises aerogel radiator and composite mirrors in a novel hybrid optics design, where either direct or reflected light could be imaged in a high-packed and high-segmented photon detector. The first RICH module was assembled during the second half of 2017 and installed at the beginning of January 2018, in time for the start of the experiment. The second RICH module, planned with the goal to be ready for the beginning of the operation with polarized targets, has been timely built despite the complications caused by the pandemic crisis and successfully installed in June 2022. The detector performance is here discussed with emphasis on the operation and stability during the data-taking, calibration and alignment procedures, reconstruction and pattern recognition algorithms, and particle identification.

The Heavy Photon Search experiment took its first data in a 2015 engineering run using a 1.056 GeV, 50 nA electron beam provided by CEBAF at the Thomas Jefferson National Accelerator Facility, searching for an electro-produced dark photon. Using 1.7 days (1170 nb$^{-1}$) of data, a search for a resonance in the $e^{+}e^{-}$ invariant mass distribution between 19 and 81 MeV/c$^{2}$ showed no evidence of dark photon decays above the large QED background, confirming earlier searches and demonstrating the full functionality of the experiment. Upper limits on the square of the coupling of the dark photon to the Standard Model photon are set at the level of 6$\times$10$^{-6}$. In addition, a search for displaced dark photon decays did not rule out any territory but resulted in a reliable analysis procedure that will probe hitherto unexplored parameter space with future, higher luminosity runs.

We present results of the detailed study of several hundred Hamamatsu H12700 Multianode Photomultiplier Tubes (MaPMTs), characterizing their response to the Cherenkov light photons in the second Ring Imaging Cherenkov detector, a part of the CLAS12 upgrade at Jefferson Lab. The total number of pixels studied was 25536. The single photoelectron spectra were measured for each pixel at different high voltages and light intensities of the laser test setup. Using the same dedicated front-end electronics as in the first RICH detector, the setup allowed us to characterize each pixel's properties such as gain, quantum efficiency, signal crosstalk between neighboring pixels, and determine the signal threshold values to optimize their efficiency to detect Cherenkov photons. A recently published state-of-the-art mathematical model, describing photon detector response functions measured in low light conditions, was extended to include the description of the crosstalk contributions to the spectra. The database of extracted parameters will be used for the final selection of the MaPMTs, their arrangement in the new RICH detector, and the optimization of the operational settings of the front-end electronics. The results show that the characteristics of the H12700 MaPMTs satisfy our requirements for the position-sensitive single photoelectron detectors.

Using The VXS Trigger Processor -Detector Beam Experiment -CLAS12 Forward Tagger CalorimeterAt Jefferson Lab we design and build circuits and firmware to:• digitize the small, ultra-fast electrical signals produced by the experimental detectors.• look for patterns in the data and select the events of interest.The Flash Analog to Digital Converter (FADC250) samples thousands of analog signals 250 million times per second.Each of the signals can be really fast: done and gone in just a few billionths of a second.JLab Printed Circuit Boards (PCBs) carry many integrated circuits like Field-Programmable-Gate-Arrays (FPGA), Analog-to-Digital-Converters (ADC), Serializer/Deserializer (SerDes), and many other types.

The CLAS12 Data Acquisition System was designed and built as part of the CLAS12 detector project in Hall B at Jefferson Laboratory. This article contains a full description of the system, including requirements, design, hardware, and software descriptions, as well as the achieved performance. The associated computing, network, and slow controls systems are also described.

The first module of the hybrid-optics large-area CLAS12 RICH at JLab has been recently put into operation using for the first time the well known Hamamatsu H8500 MAPMT and the new single-photon dedicated H12700, for a total of about 400 MAPMTs and 25000 pixels. The photon detector must efficiently detect single photons in the visible and near-UV light region, provide a fast response for background rejection and pattern recognition, and have a spatial resolution of less than 1 cm over an area of approximate to 1 m(2). Each front-end readout unit is composed of three electronic boards with specific tasks directly connected to groups of 2 or 3 sensors. The core of the readout is composed of MAROC3 and FPGA chips. The MAROC3 chip is able to discriminate the 64 signals from one MAPMT and to produce 64 corresponding binary outputs with 100% efficiency starting at a small fraction of the single-photon signal, while the FPGA chip provides 1 ns TDC capability with 8 mu s maximum latency and acts as a DAQ controller. The system is designed to be almost dead-time free at the foreseen 20 kHz CLAS12 trigger rate. The best working conditions for single-photon detection have been studied at laser stands, test beams, and with the JLab electron beam data. A report of the photon detector preparation, commissioning and operation is here discussed.

The High Threshold Cherenkov Counter (HTCC) is one of the detector systems of the CLAS12 spectrometer, and is used to generate a fast trigger signal in electron scattering experiments in the polar angle range from 5°to 35°. The HTCC is installed in front of the drift chambers and introduces a minimal amount of additional material within the acceptance. The HTCC is one unit whose core component is a multifocal mirror that consists of 60 lightweight ellipsoidal mirrors. It is important that the HTCC provides efficient coverage of the CLAS12 forward acceptance with no gaps. In order to achieve this, each sector of the CLAS12 Forward Detector is covered by 2 identical half-sector mirrors that focus Cherenkov light on 8 phototubes. The HTCC has a total of 48 channels with Electron Tubes 9823QKB photomultipliers that have a 5-in quartz face plate to detect Cherenkov light. The system provides rejection of charged π-mesons with momenta below 4.8 GeV for the reliable identification of scattered electrons. In this paper the details of the design, construction, calibration, and performance results of the HTCC are presented.

This article describes the CLAS12 Trigger System. The simulation, hardware, and software design, as well as all validation procedures, are discussed. The firmware development tools used are discussed as well, including our experience with VIVADO High Level Synthesis.

For the 12 GeV upgrade of Jefferson Laboratory, a Silicon Vertex Tracker (SVT) has been designed for the CLAS12 spectrometer using single-sided microstrip sensors fabricated by Hamamatsu Photonics. The sensors have a graded angle design to minimize dead areas and a readout pitch of 156 nm, with intermediate strips. Each double-sided SVT module hosts three daisy-chained sensors on each side with a full strip length of 33 cm. There are 512 channels per module, read out by four Fermilab Silicon Strip Readout (FSSR2) chips, featuring data-driven architecture, mounted on a rigid-flex hybrid board. The modules are assembled in a barrel configuration using a unique cantilevered geometry to minimize the amount of material in the tracking volume. This paper is focused on the design, qualification of the performance, and experience in operating and commissioning the tracker during the first year of the data taking.

A large area imaging Cherenkov detector is under construction to provide hadron identification in the momentum range between 3 and 8GeV/c for the CLAS12 exeperiment at the new 12GeV electron beam of the Jefferson Laboratory (JLab). The detector adopts a hybrid optics solution with aerogel radiator, light planar and spherical mirrors and highly-segmented photon detectors. Cherenkov photons will be imaged either directly (for forward tracks) or after two mirror reflections (large angle tracks). The status of the detector construction is here reported.

The Heavy Photon Search experiment (HPS) is searching for a new gauge boson, the so-called "heavy photon." Through its kinetic mixing with the Standard Model photon, this particle could decay into an electron-positron pair. It would then be detectable as a narrow peak in the invariant mass spectrum of such pairs, or, depending on its lifetime, by a decay downstream of the production target. The HPS experiment is installed in Hall-B of Jefferson Lab. This article presents the design and performance of one of the two detectors of the experiment, the electromagnetic calorimeter, during the runs performed in 2015-2016. The calorimeter's main purpose is to provide a fast trigger and reduce the copious background from electromagnetic processes through matching with a tracking detector. The detector is a homogeneous calorimeter, made of 442 lead-tungstate (PbWO4) scintillating crystals, each read out by an avalanche photodiode coupled to a custom trans-impedance amplifier.

The Heavy Photon Search (HPS), an experiment to search for a hidden sector photon in fixed target electroproduction, is preparing for installation at the Thomas Jefferson National Accelerator Facility (JLab) in the Fall of 2014. As the first stage of this project, the HPS Test Run apparatus was constructed and operated in 2012 to demonstrate the experiment׳s technical feasibility and to confirm that the trigger rates and occupancies are as expected. This paper describes the HPS Test Run apparatus and readout electronics and its performance. In this setting, a heavy photon can be identified as a narrow peak in the e+e− invariant mass spectrum above the trident background or as a narrow invariant mass peak with a decay vertex displaced from the production target, so charged particle tracking and vertexing are needed for its detection. In the HPS Test Run, charged particles are measured with a compact forward silicon microstrip tracker inside a dipole magnet. Electromagnetic showers are detected in a PbW04 crystal calorimeter situated behind the magnet, and are used to trigger the experiment and identify electrons and positrons. Both detectors are placed close to the beam line and split top-bottom. This arrangement provides sensitivity to low-mass heavy photons, allows clear passage of the unscattered beam, and avoids the spray of degraded electrons coming from the target. The discrimination between prompt and displaced e+e− pairs requires the first layer of silicon sensors be placed only 10 cm downstream of the target. The expected signal is small, and the trident background huge, so the experiment requires very large statistics. Accordingly, the HPS Test Run utilizes high-rate readout and data acquisition electronics and a fast trigger to exploit the essentially 100% duty cycle of the CEBAF accelerator at JLab.

In this paper, the architecture of the Clas12 Micromegas vertex tracker readout is described and the details of its implementation are given. The innovations allowing to meet the challenging requirements of the tracker operation are presented. The system performance is evaluated based on detector tests with a cosmic rays trigger and on standalone high rate validation tests. Finally, the perspectives to adapt the readout system or a part of it to other experiments are discussed.

The design of the Trigger Interface and Distribution (TID) board for the 12 GeV Upgrade at Thomas Jefferson National Accelerator Facility (TJNAF) is described. The TID board distributes a low jitter system clock, synchronized trigger, and synchronized multi-purpose SYNC signal. The TID also initiates readout for the data acquisition front-end crate. With the TID boards, a multi-crate system can be setup for large scale nuclear physics experiments. The TID board can be selectively populated as a Trigger Interface (TI) board, or a Trigger Distribution (TD) board for the 12 GeV upgrade experiments. When the TID is populated as a TI, The TID can be located in the VXS crate and distribute the CLOCK/TRIGGER/SYNC (CTS) through the VXS/P0 connector; it can also be located in the standard VME64 crate, and distribute the CTS through the VME/P2 connector or front panel connectors. It initiates the data acquisition for the front-end crate where the TI is positioned in. When the TID is populated as a TD, it fans out the CTS from the trigger supervisor to the front-end crates through optical fibres. The TD board monitors the trigger processing on the TI boards, and sends feedback to the Trigger Supervisor (TS) board for event readout flow control. A Field Programmable Gate Arrays (FPGA) is utilised on the TID board to provide programmability. The TID board was intensively tested on the bench. The TID production version has been released to industry for contract manufacturing.