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 Muon g-2 Experiment at Fermilab (E989) will measure the muon magnetic anomaly with unprecedented precision (0.14 ppm), which yields a factor of 4 improvement with respect to the previous ...measurements at Brookhaven National Laboratory (BNL) (E821). To achieve this goal, the relative response of each calorimeter channel must be calibrated and monitored at a level better than <inline-formula> <tex-math notation="LaTeX">10^{-3} </tex-math></inline-formula> in the time window of the muon fill. The calibration system uses a laser source and photodetectors. The data acquisition (DAQ) of the system is designed around two field-programmable gate array (FPGA)-based boards and a custom crate bus. The front-end board manages the photodetector operation and signal processing and performs a first-level data concentration task. Up to 12 FPGA boards can be housed in a 6U crate. A readout master controls the boards, implements event-building functionalities, manages the monitoring interface, and facilitates calibration and debugging tasks. A gigabit-ethernet interface is used to transfer data to the on-line farm for storage and further processing. Presently, the system is working at Fermi National Accelerator Laboratory (FNAL). In this article, we present the DAQ system design, run control user interface, and system evaluation.
Triggerless DAQ system for a light based detector Mastroianni, S.; Iacovacci, M.; Marignetti, F.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
March 2023, 2023-03-00, Volume:
1048
Journal Article
Peer reviewed
The utilization of various types of photon detectors, generally referred to as light based detectors, is widespread in many fields of high energy physics, nuclear physics, astrophysics and medical ...imaging to measure scintillation photons or Cherenkov light. Both the traditional photomultiplier tubes (PMTs), still the most commonly used, and the silicon photomultipliers (SiPMs) in rapid development in the last years show good performance. The sensitivity down to single photoelectron (PE), the wide dynamic range and the fast timing characteristics can be exploited thanks to a careful optimization of the readout electronics, trigger and DAQ.
In applications where a high efficiency is required at low energy threshold (as for rare-event search experiments), in a typical trigger-based DAQ architecture, lowering the number of coincident signals for the event selection is mandatory with the consequent heavy increase of data rate that could not be sustained by the DAQ chain.
We have developed a triggerless data collection scheme for a light based detector that relies on a new generation of waveform digitizer board, developed by CAEN and able to manage an independent data acquisition on each channel. This paper describes the implementation and the performance of the triggerless DAQ system.
The evolution of the cosmic ray primary composition in the energy range 106–107 GeV (i.e. the “knee” region) is studied by means of the e.m. and muon data of the Extensive Air Shower EAS-TOP array ...(Campo Imperatore, National Gran Sasso Laboratories). The measurement is performed through: (a) the correlated muon number (Nμ) and shower size (Ne) spectra, and (b) the evolution of the average muon numbers and their distributions as a function of the shower size. From analysis (a) the dominance of helium primaries at the knee, and therefore the possibility that the knee itself is due to a break in their energy spectrum (at EkHe=(3.5±0.3)×106 GeV) are deduced. Concerning analysis (b), the measurement accuracies allow the classification in terms of three mass groups: light (p,He), intermediate (CNO), and heavy (Fe). At primary energies E0≈106 GeV the results are consistent with the extrapolations of the data from direct experiments. In the knee region the obtained evolution of the energy spectra leads to: (i) an average steep spectrum of the light mass group (γp,He>3.1), (ii) a spectrum of the intermediate mass group harder than the one of the light component (γCNO≃2.75, possibly bending at EkCNO≈(6–7)×106 GeV), (iii) a constant slope for the spectrum of the heavy primaries (γFe≃2.3–2.7) consistent with the direct measurements. In the investigated energy range, the average primary mass increases from 〈lnA〉=1.6–1.9 at E0≃1.5×106 GeV to 〈lnA〉=2.8–3.1 at E0≃1.5×107 GeV. The result supports the standard acceleration and propagation models of galactic cosmic rays that predict rigidity dependent cut-offs for the primary spectra of the different nuclei. The uncertainties connected to the hadronic interaction model (QGSJET in CORSIKA) used for the interpretation are discussed.
We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time ...projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03) ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3) events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47} cm^{2} for a WIMP mass of 28 GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.
CALPRO, an unconventional calorimetry approach Iacovacci, M.; Mastroianni, S.; Cimmino, B. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2019, Volume:
936
Journal Article
Peer reviewed
We propose a calorimetry approach unconventional and innovative. The method is based on the measurement of the lateral distribution of charged particles around the shower axis, it has been used for ...the first time in the energy determination of Extensive Air Showers at very high energy (>100 TeV) with single layer detector, providing an energy determination with resolution of about 10% for energies above 100 TeV. It has some peculiar characteristics which can be summarized in the following three points: (1) measurement of the shower energy by means of a single sampling; (2) calorimetry which renounces the classic concept of containment of the shower; (3) possibility to separate primary masses. In order to extend this technique at lower energies, specific simulations have been performed through GEANT4 in the energy range 100 GeV–10 TeV for different particles.