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6.10. Generation of random telegraph noise (left) and of 1/f noise (right) by trapping-detrapping. Adapted from Compagnoni et al. [53].

6.10. Generation of random telegraph noise (left) and of 1/f noise (right) by trapping-detrapping. Adapted from Compagnoni et al. [53].

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This document is part of Part 1 'Principles and Methods' of Subvolume B 'Detectors for Particles and Radiation' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Section '3.6 Signal Processing for Particle Detectors' of Chapter '3 Particle Detectors and Detector Systems' wit...

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... It is worthwhile to note that this component is a combination of detector and FEE interplay because, if the noise source is located within the reset device, the noise is induced and determined by the detector through . In case the charge preamplifier employs a pulsed reset a=0; however pulsed reset preamplifiers can suffer from an additional noise contribution known as kTC noise, arising from the sampling of the thermal noise of the switch resistance on the feedback capacitance at the end of the reset phase [35], and can suffer also from stability issues that might result in similar fluctuations on the output baseline level [36]. These noise contributions can however be removed by filtering the low-frequency band of the noise spectrum, which can be done using an AC coupling or timevariant filtering techniques such as correlated double sampling (CDS) [35]. ...
... In case the charge preamplifier employs a pulsed reset a=0; however pulsed reset preamplifiers can suffer from an additional noise contribution known as kTC noise, arising from the sampling of the thermal noise of the switch resistance on the feedback capacitance at the end of the reset phase [35], and can suffer also from stability issues that might result in similar fluctuations on the output baseline level [36]. These noise contributions can however be removed by filtering the low-frequency band of the noise spectrum, which can be done using an AC coupling or timevariant filtering techniques such as correlated double sampling (CDS) [35]. ...
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The electronic noise is a key-issue during the phases of design, integration and characterization of a detection system for ionizing radiation, as it determines both its ultimate and actual performances. The precise identification and quantification of all noise sources and associated components allow to implement specific strategies for their control and minimization during the system design and manufacturing phases, to disentangle all noise contributions, and to verify their correspondence with the expectations during the system characterization. An effective approach to the electronic noise problem requires to consider in detail all the parts of the detection system but it is not so rare to still observe that the electronic noise is erroneously confused or interpreted as the noise of the electronics or as the quadratic sum of the electronics’ and detector’s noise, usually reducing the latter to that one associated to its dark current only. In this paper, a detailed analysis of the noise model of a radiation detection system employing a semiconductor detector is presented using a unified approach which takes into account all sources and causes of electronic noise and their reciprocal interaction. The noise related to the generation, transport and loss of the signal charge in the detector are analyzed in detail and, in particular, the charge trapping and detrapping processes, showing how their contributions could be not negligible even in detectors based on high purity semiconductors. The unified approach allows to disclose the interplay between the detector, the interconnection and the front-end electronics showing that some noise contributions cannot be attributed exclusively to a single part, but it is correct to refer to them as system noises. Several examples taken from experimental data are presented and discussed and a method to determine the dielectric noise introduced by the interconnection and the detector is described. The concept of Equivalent Noise Energy is formalized revealing how it is useful to compare systems employing detectors made with different semiconductors and eventually affected by charge trapping. The analysis is developed assuming semiconductor detectors but can be easily applied to system using other types of radiation detectors.
... The shaping circuit [20] receives the signals produced by the active calorimeter material and generates a typical pulse shape in its output. Among the benefits of such an operation are to increase the signal-to-noise ratio and have a standard pulse (with controlled width, amplitude, and shape) to better cope with the analog-to-digital converter (ADC) specifications (sampling frequency, input signal range, etc.) [21]. After signal acquisition and digitization, at the trigger or analysis level, the digital information from the calorimeter cells may be used to recover the sampled energy amplitude and estimate the particle time-of-flight by using specific energy estimation strategies [22]. ...
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Calorimeters play an important role in high-energy physics experiments. Their design includes electronic instrumentation, signal processing chain, computing infrastructure, and also a good understanding of their response to particle showers produced by the interaction of incoming particles. This is usually supported by full simulation frameworks developed for specific experiments so that their access is restricted to the collaboration members only. Such restrictions limit the general-purpose developments that aim to propose innovative approaches to signal processing, which may include machine learning and advanced stochastic signal processing models. This work presents the Lorenzetti Showers, a general-purpose framework that mainly targets supporting novel signal reconstruction and triggering strategies using segmented calorimeter information. This framework fully incorporates developments down to the signal processing chain level (signal shaping, energy estimation, and noise mitigation techniques) to allow advanced signal processing approaches in modern calorimetry and triggering systems. The developed framework is flexible enough to be extended in different directions. For instance, it can become a tool for the phenomenology community to go beyond the usual detector design and physics process generation approaches. https://authors.elsevier.com/a/1gX3e2OInn%7EDa
... A test pulse capacitance C inj has been implemented on-chip to inject a known charge at the input of the CSA to evaluate the performance of the readout chain. The shaper performs correlated-doublesampling (CDS), reducing the low-frequency and kT/C noise introduced by the synchronous reset mechanism [8]. In order to achieve high framerates, a sample-and-hold channel buffer is necessary to allow integrate-while-read operation. ...
... The shaper performs Correlated-Double-Sampling (CDS), reducing the low-frequency and kT/C noise introduced by the synchronous reset mechanism [4]. In order to achieve high framerates, a sample-and-hold channel buffer is necessary to allow integrate-while-read operation. ...
... • " f parallel" noise which arises from thermal fluctuations in the dielectric components such as the circuit boards and wire carrier boards. Upon integration on the input capacitance this noise acts as a series 1/ f noise [21]. By design, this noise is much lower than other sources. ...
... The ENC is defined as the number of instantaneously collected electrons required so that their peak ADC count is equal to the root mean square (RMS) of the noise measured, also in the units of ADC counts. The ENC from the noise sources listed above can be approximated as [21,22]: ...
... A 2 =0.9 and A 3 =1.0 [21]. ...
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