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Kim H, Hua Y, Epel B, Sundramoorthy S, Halpern H, Chen CT, Kao CM. A Preclinical Positron Emission Tomography (PET) and Electron-Paramagnetic-Resonance-Imaging (EPRI) Hybrid System: PET Detector Module. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2023; 7:794-801. [PMID: 37981977 PMCID: PMC10655702 DOI: 10.1109/trpms.2023.3301788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2023]
Abstract
We report the design and experimental validation of a compact positron emission tomography (PET) detector module (DM) intended for building a preclinical PET and electron-paramagnetic-resonance-imaging hybrid system that supports sub-millimeter image resolution and high-sensitivity, whole-body animal imaging. The DM is eight detector units (DU) in a row. Each DU contains 12×12 lutetium-yttrium oxyorthosilicate (LYSO) crystals having a 1.05 mm pitch read by 4×4 silicon photomultipliers (SiPM) having a 3.2 mm pitch. A small-footprint, highly-multiplexing readout employing only passive electronics is devised to produce six outputs for the DM, including two outputs derived from SiPM cathodes for determining event time and active DU and four outputs derived from SiPM anodes for determining energy and active crystal. Presently, we have developed two DMs that are 1.28×10.24 cm2 in extent and approximately 1.8 cm in thickness, with their outputs sampled at 0.7 GS/s and analyzed offline. For both DMs, our results show successfully discriminated DUs and crystals. With no correction for SiPM nonlinearity, the average energy resolution for crystals in a DU ranges from 14% to 16%. While not needed for preclinical imaging, the DM may support 300-400 ps time-of-flight resolution.
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Affiliation(s)
- Heejong Kim
- Department of Radiology, University of Chicago, Chicago, Illinois, USA
| | - Yuexuan Hua
- Raycan Technology Co., Ltd., Suzhou, Jiangsu, China
| | - Boris Epel
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, Illinois, USA
| | | | - Howard Halpern
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, Illinois, USA
| | - Chin-Tu Chen
- Department of Radiology, University of Chicago, Chicago, Illinois, USA
| | - Chien-Min Kao
- Department of Radiology, University of Chicago, Chicago, Illinois, USA
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Massimi L, Suaris T, Hagen CK, Endrizzi M, Munro PRT, Havariyoun G, Hawker PMS, Smit B, Astolfo A, Larkin OJ, Waltham RM, Shah Z, Duffy SW, Nelan RL, Peel A, Jones JL, Haig IG, Bate D, Olivo A. Volumetric High-Resolution X-Ray Phase-Contrast Virtual Histology of Breast Specimens With a Compact Laboratory System. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:1188-1195. [PMID: 34941505 PMCID: PMC7612751 DOI: 10.1109/tmi.2021.3137964] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The assessment of margin involvement is a fundamental task in breast conserving surgery to prevent recurrences and reoperations. It is usually performed through histology, which makes the process time consuming and can prevent the complete volumetric analysis of large specimens. X-ray phase contrast tomography combines high resolution, sufficient penetration depth and high soft tissue contrast, and can therefore provide a potential solution to this problem. In this work, we used a high-resolution implementation of the edge illumination X-ray phase contrast tomography based on "pixel-skipping" X-ray masks and sample dithering, to provide high definition virtual slices of breast specimens. The scanner was originally designed for intra-operative applications in which short scanning times were prioritised over spatial resolution; however, thanks to the versatility of edge illumination, high-resolution capabilities can be obtained with the same system simply by swapping x-ray masks without this imposing a reduction in the available field of view. This makes possible an improved visibility of fine tissue strands, enabling a direct comparison of selected CT slices with histology, and providing a tool to identify suspect features in large specimens before slicing. Combined with our previous results on fast specimen scanning, this works paves the way for the design of a multi-resolution EI scanner providing intra-operative capabilities as well as serving as a digital pathology system.
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Shida JF, Spieglan E, Adams BW, Angelico E, Domurat-Sousa K, Elagin A, Frisch HJ, La Riviere P, Squires AH. Low-Dose High-Resolution TOF-PET Using Ionization-activated Multi-State Low-Z Detector Media. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT 2021; 1017:165801. [PMID: 34690392 PMCID: PMC8530277 DOI: 10.1016/j.nima.2021.165801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We propose PET scanners using low atomic number media that undergo a persistent local change of state along the paths of the Compton recoil electrons. Measurement of the individual scattering locations and angles, deposited energies, and recoil electron directions allows using the kinematical constraints of the 2-body Compton scattering process to perform a statistical time-ordering of the scatterings, with a high probability of precisely identifying where the gamma first interacted in the detector. In these cases the Line-of-Response is measured with high resolution, determined by the underlying physics processes and not the detector segmentation. There are multiple such media that act through different mechanisms. As an example in which the change of state is quantum-mechanical through a change in molecular configuration, rather than thermodynamic, as in a bubble chamber, we present simulations of a two-state photoswitchable organic dye, a 'Switchillator', that is activated to a fluorescent-capable state by the ionization of the recoil electrons. The activated state is persistent, and can be optically excited multiple times to image individual activated molecules. Energy resolution is provided by counting the activated molecules. Location along the LOR is implemented by large-area time-of-flight MCP-PMT photodetectors with single photon time resolution in the tens of ps and sub-mm spatial resolution. Simulations indicate a large reduction of dose.
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Affiliation(s)
- J F Shida
- Enrico Fermi Institute, The University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637
| | - E Spieglan
- Enrico Fermi Institute, The University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637
| | - B W Adams
- Quantum Optics Applied Research, Naperville, IL 60564
| | - E Angelico
- Enrico Fermi Institute, The University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637
| | - K Domurat-Sousa
- Enrico Fermi Institute, The University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637
| | - A Elagin
- Enrico Fermi Institute, The University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637
| | - H J Frisch
- Enrico Fermi Institute, The University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637
| | - P La Riviere
- Department of Radiology, The University of Chicago, Billings Hospital, P220, 5841 South Maryland Avenue, MC2026, Chicago, IL 60637
| | - A H Squires
- Pritzker School of Molecular Engineering, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637
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Schaart DR, Schramm G, Nuyts J, Surti S. Time of Flight in Perspective: Instrumental and Computational Aspects of Time Resolution in Positron Emission Tomography. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2021; 5:598-618. [PMID: 34553105 PMCID: PMC8454900 DOI: 10.1109/trpms.2021.3084539] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The first time-of-flight positron emission tomography (TOF-PET) scanners were developed as early as in the 1980s. However, the poor light output and low detection efficiency of TOF-capable detectors available at the time limited any gain in image quality achieved with these TOF-PET scanners over the traditional non-TOF PET scanners. The discovery of LSO and other Lu-based scintillators revived interest in TOF-PET and led to the development of a second generation of scanners with high sensitivity and spatial resolution in the mid-2000s. The introduction of the silicon photomultiplier (SiPM) has recently yielded a third generation of TOF-PET systems with unprecedented imaging performance. Parallel to these instrumentation developments, much progress has been made in the development of image reconstruction algorithms that better utilize the additional information provided by TOF. Overall, the benefits range from a reduction in image variance (SNR increase), through allowing joint estimation of activity and attenuation, to better reconstructing data from limited angle systems. In this work, we review these developments, focusing on three broad areas: 1) timing theory and factors affecting the time resolution of a TOF-PET system; 2) utilization of TOF information for improved image reconstruction; and 3) quantification of the benefits of TOF compared to non-TOF PET. Finally, we offer a brief outlook on the TOF-PET developments anticipated in the short and longer term. Throughout this work, we aim to maintain a clinically driven perspective, treating TOF as one of multiple (and sometimes competitive) factors that can aid in the optimization of PET imaging performance.
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Affiliation(s)
- Dennis R Schaart
- Section Medical Physics & Technology, Radiation Science and Technology Department, Delft University of Technology, 2629 JB Delft, The Netherlands
| | - Georg Schramm
- Department of Imaging and Pathology, Division of Nuclear Medicine, KU/UZ Leuven, 3000 Leuven, Belgium
| | - Johan Nuyts
- Department of Imaging and Pathology, Division of Nuclear Medicine, KU/UZ Leuven, 3000 Leuven, Belgium
| | - Suleman Surti
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 USA
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Schaart DR. Physics and technology of time-of-flight PET detectors. Phys Med Biol 2021; 66. [PMID: 33711831 DOI: 10.1088/1361-6560/abee56] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 03/12/2021] [Indexed: 01/04/2023]
Abstract
The imaging performance of clinical positron emission tomography (PET) systems has evolved impressively during the last ∼15 years. A main driver of these improvements has been the introduction of time-of-flight (TOF) detectors with high spatial resolution and detection efficiency, initially based on photomultiplier tubes, later silicon photomultipliers. This review aims to offer insight into the challenges encountered, solutions developed, and lessons learned during this period. Detectors based on fast, bright, inorganic scintillators form the scope of this work, as these are used in essentially all clinical TOF-PET systems today. The improvement of the coincidence resolving time (CRT) requires the optimization of the entire detection chain and a sound understanding of the physics involved facilitates this effort greatly. Therefore, the theory of scintillation detector timing is reviewed first. Once the fundamentals have been set forth, the principal detector components are discussed: the scintillator and the photosensor. The parameters that influence the CRT are examined and the history, state-of-the-art, and ongoing developments are reviewed. Finally, the interplay between these components and the optimization of the overall detector design are considered. Based on the knowledge gained to date, it appears feasible to improve the CRT from the values of 200-400 ps achieved by current state-of-the-art TOF-PET systems to about 100 ps or less, even though this may require the implementation of advanced methods such as time resolution recovery. At the same time, it appears unlikely that a system-level CRT in the order of ∼10 ps can be reached with conventional scintillation detectors. Such a CRT could eliminate the need for conventional tomographic image reconstruction and a search for new approaches to timestamp annihilation photons with ultra-high precision is therefore warranted. While the focus of this review is on timing performance, it attempts to approach the topic from a clinically driven perspective, i.e. bearing in mind that the ultimate goal is to optimize the value of PET in research and (personalized) medicine.
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Affiliation(s)
- Dennis R Schaart
- Delft University of Technology, Radiation Science & Technology dept., section Medical Physics & Technology, Mekelweg 15, 2629 JB Delft, The Netherlands
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Angelico E, Elagin A, Frisch HJ, Spieglan E, Adams BW, Foley MR, Minot MJ. Air-transfer production method for large-area picosecond photodetectors. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:053105. [PMID: 32486706 DOI: 10.1063/5.0008606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/02/2020] [Indexed: 06/11/2023]
Abstract
We have designed and prototyped the process steps for the batch production of large-area micro-channel-plate photomultipliers (MCP-PMT) using the "air-transfer" assembly process developed with single LAPPDTM modules. Results are presented addressing the challenges of designing a robust package that can transmit large numbers of electrical signals for pad or strip readout from inside the vacuum tube and of hermetically sealing the large-perimeter window-body interface. We have also synthesized a photocathode in a large-area low-aspect-ratio volume and have shown that the micro-channel plates recover their functionality after cathode synthesis. These steps inform a design for a multi-module batch facility employing dual nested low-vacuum and ultra-high-vacuum systems in a small-footprint. The facility design provides full access to multiple MCP-PMT modules prior to hermetic pinch-off for leak-checking and real-time photocathode optimization.
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Affiliation(s)
- E Angelico
- Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - A Elagin
- Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - H J Frisch
- Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - E Spieglan
- Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - B W Adams
- Incom, Inc., Charlton, Massachusetts 01507, USA
| | - M R Foley
- Incom, Inc., Charlton, Massachusetts 01507, USA
| | - M J Minot
- Incom, Inc., Charlton, Massachusetts 01507, USA
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Kim KB, Choi Y, Jung J, Lee S, Choe HJ, Leem HT. Analog and digital signal processing method using multi-time-over-threshold and FPGA for PET. Med Phys 2018; 45:4104-4111. [PMID: 30043982 DOI: 10.1002/mp.13101] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 07/13/2018] [Accepted: 07/13/2018] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The goal of this study was to develop an analog and digital signal processing method using multi-time-over-threshold (MTOT) and field programmable gate arrays (FPGAs) to extract PET event information by using the internal clock of FPGA (~350 MHz), without ADC and TDC. METHODS The PET detector modules were composed of a 4 × 4 matrix of 3 × 3 × 20 mm3 LYSO and 4 × 4 SiPM array. Output charge signals of PET detector modules were amplified and fed into four comparators to generate trigger signals. The energy of the detected gamma ray was calculated by integrating the digitized pulse and the arrival time was determined from the time stamp of the lowest trigger signal by FPGA. The data packet containing energy, time, and position information was stored in list mode on the host computer. RESULTS The performance of analog and digital signal processing circuits using MTOT method and FPGA was evaluated by measuring energy and time resolution of the proposed method and the values were 19% and 900 ps, respectively. CONCLUSION This study demonstrated that the proposed MTOT method consisting of only FPGA without ADC and TDC could provide a simple and cost-effective analog and digital signal processing system for PET.
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Affiliation(s)
- Kyu Bom Kim
- Department of Electronic Engineering, Sogang University, 1 Shinsu-Dong, Mapo-Gu, Seoul, 121-742, South Korea
| | - Yong Choi
- Department of Electronic Engineering, Sogang University, 1 Shinsu-Dong, Mapo-Gu, Seoul, 121-742, South Korea
| | - Jiwoong Jung
- Department of Electronic Engineering, Sogang University, 1 Shinsu-Dong, Mapo-Gu, Seoul, 121-742, South Korea
| | - Sangwon Lee
- Department of Electronic Engineering, Sogang University, 1 Shinsu-Dong, Mapo-Gu, Seoul, 121-742, South Korea
| | - Hyeok-Jun Choe
- Department of Electronic Engineering, Sogang University, 1 Shinsu-Dong, Mapo-Gu, Seoul, 121-742, South Korea
| | - Hyun Tae Leem
- Department of Electronic Engineering, Sogang University, 1 Shinsu-Dong, Mapo-Gu, Seoul, 121-742, South Korea
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Won JY, Ko GB, Lee JS. Delay grid multiplexing: simple time-based multiplexing and readout method for silicon photomultipliers. Phys Med Biol 2016; 61:7113-7135. [DOI: 10.1088/0031-9155/61/19/7113] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Kim H, Chen CT, Eclov N, Ronzhin A, Murat P, Ramberg E, Los S, Kao CM. A Silicon Photo-multiplier Signal Readout Using Strip-line and Waveform Sampling for Positron Emission Tomography. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT 2016; 830:119-129. [PMID: 27746514 PMCID: PMC5058446 DOI: 10.1016/j.nima.2016.05.085] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A strip-line and waveform sampling based readout is a signal multiplexing method that can efficiently reduce the readout channels while fully exploiting the fast time characteristics of photo-detectors such as the SiPM. We have applied this readout method for SiPM-based time-of-flight (TOF) positron emission tomography (PET) detectors. We have prototyped strip-line boards in which 8 SiPMs (pitch 5.2 mm) are connected by using a single strip-line, and the signals appearing at the ends of the strip-line are acquired by using the DRS4 waveform sampler at a nominal sampling frequency of 1-5 GS/s. Experimental tests using laser and LYSO scintillator are carried out to assess the performance of the strip-line board. Each SiPM position, which is inferred from the arrival time difference of the two signals at the ends of the strip-line, is well identified with 2.6 mm FWHM resolution when the SiPMs are coupled to LYSO crystals and irradiated by a 22Na source. The average energy and coincidence time resolution responding to 511 keV photons are measured to be ~32% and ~510 ps FWHM, respectively, at a 5.0 GS/s DRS4 sampling rate. The results show that the sampling rate can be lowered to 1.5 GS/s without performance degradation. These encouraging initial test results indicate that the strip-line and waveform sampling readout method is applicable for SiPM-based TOF PET development.
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Affiliation(s)
- H. Kim
- Department of Radiology, University of Chicago, Chicago, IL 60637
| | - C.-T. Chen
- Department of Radiology, University of Chicago, Chicago, IL 60637
| | - N. Eclov
- Department of Radiology, University of Chicago, Chicago, IL 60637
| | - A. Ronzhin
- Fermi National Accelerator Laboratory, IL, US
| | - P. Murat
- Fermi National Accelerator Laboratory, IL, US
| | - E. Ramberg
- Fermi National Accelerator Laboratory, IL, US
| | - S. Los
- Fermi National Accelerator Laboratory, IL, US
| | - C.-M. Kao
- Department of Radiology, University of Chicago, Chicago, IL 60637
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Kim H, Chen CT, Eclov N, Ronzhin A, Murat P, Ramberg E, Los S, Wyrwicz AM, Li L, Kao CM. A feasibility study of a PET/MRI insert detector using strip-line and waveform sampling data acquisition. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT 2015; 784:557-564. [PMID: 25937685 PMCID: PMC4415628 DOI: 10.1016/j.nima.2014.12.080] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We are developing a time-of-flight Positron Emission Tomography (PET) detector by using silicon photo-multipliers (SiPM) on a strip-line and high speed waveform sampling data acquisition. In this design, multiple SiPMs are connected on a single strip-line and signal waveforms on the strip-line are sampled at two ends of the strip to reduce readout channels while fully exploiting the fast time response of SiPMs. In addition to the deposited energy and time information, the position of the hit SiPM along the strip-line is determined by the arrival time difference of the waveform. Due to the insensitivity of the SiPMs to magnetic fields and the compact front-end electronics, the detector approach is highly attractive for developing a PET insert system for a magnetic resonance imaging (MRI) scanner to provide simultaneous PET/MR imaging. To investigate the feasibility, experimental tests using prototype detector modules have been conducted inside a 9.4 Tesla small animal MRI scanner (Bruker BioSpec 94/30 imaging spectrometer). On the prototype strip-line board, 16 SiPMs (5.2 mm pitch) are installed on two strip-lines and coupled to 2 × 8 LYSO scintillators (5.0 × 5.0 × 10.0 mm3 with 5.2 mm pitch). The outputs of the strip-line boards are connected to a Domino-Ring-Sampler (DRS4) evaluation board for waveform sampling. Preliminary experimental results show that the effect of interference on the MRI image due to the PET detector is negligible and that PET detector performance is comparable with the results measured outside the MRI scanner.
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Affiliation(s)
- H. Kim
- Department of Radiology, University of Chicago, Chicago, IL 60637, USA
| | - C.-T. Chen
- Department of Radiology, University of Chicago, Chicago, IL 60637, USA
| | - N. Eclov
- Department of Radiology, University of Chicago, Chicago, IL 60637, USA
| | - A. Ronzhin
- Fermi National Accelerator Laboratory, Batavia, IL 60510, USA
| | - P. Murat
- Fermi National Accelerator Laboratory, Batavia, IL 60510, USA
| | - E. Ramberg
- Fermi National Accelerator Laboratory, Batavia, IL 60510, USA
| | - S. Los
- Fermi National Accelerator Laboratory, Batavia, IL 60510, USA
| | - Alice M. Wyrwicz
- NorthShore University HealthSystem Research Institute, Evanston, IL 60201, USA
| | - Limin Li
- NorthShore University HealthSystem Research Institute, Evanston, IL 60201, USA
| | - C.-M. Kao
- Department of Radiology, University of Chicago, Chicago, IL 60637, USA
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Kim H, Chen CT, Eclov N, Ronzhin A, Murat P, Ramberg E, Los S, Moses W, Choong WS, Kao CM. A New Time Calibration Method for Switched-capacitor-array-based Waveform Samplers. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT 2014; 767:67-74. [PMID: 25506113 PMCID: PMC4260358 DOI: 10.1016/j.nima.2014.08.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have developed a new time calibration method for the DRS4 waveform sampler that enables us to precisely measure the non-uniform sampling interval inherent in the switched-capacitor cells of the DRS4. The method uses the proportionality between the differential amplitude and sampling interval of adjacent switched-capacitor cells responding to a sawtooth-shape pulse. In the experiment, a sawtooth-shape pulse with a 40 ns period generated by a Tektronix AWG7102 is fed to a DRS4 evaluation board for calibrating the sampling intervals of all 1024 cells individually. The electronic time resolution of the DRS4 evaluation board with the new time calibration is measured to be ~2.4 ps RMS by using two simultaneous Gaussian pulses with 2.35 ns full-width at half-maximum and applying a Gaussian fit. The time resolution dependencies on the time difference with the new time calibration are measured and compared to results obtained by another method. The new method could be applicable for other switched-capacitor-array technology-based waveform samplers for precise time calibration.
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Affiliation(s)
- H. Kim
- Department of Radiology, University of Chicago, Chicago, IL 60637
| | - C.-T. Chen
- Department of Radiology, University of Chicago, Chicago, IL 60637
| | - N. Eclov
- Department of Radiology, University of Chicago, Chicago, IL 60637
| | - A. Ronzhin
- Fermi National Accelerator Laboratory, Batavia, IL, US 60510
| | - P. Murat
- Fermi National Accelerator Laboratory, Batavia, IL, US 60510
| | - E. Ramberg
- Fermi National Accelerator Laboratory, Batavia, IL, US 60510
| | - S. Los
- Fermi National Accelerator Laboratory, Batavia, IL, US 60510
| | - W. Moses
- Lawrence Berkeley National Laboratory, Berkeley, CA, US 94720
| | - W.-S. Choong
- Lawrence Berkeley National Laboratory, Berkeley, CA, US 94720
| | - C.-M. Kao
- Department of Radiology, University of Chicago, Chicago, IL 60637
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Kim H, Chen CT, Frisch H, Tang F, Kao CM. An Application of Micro-channel Plate Photomultiplier Tube to Positron Emission Tomography. PHYSICS PROCEDIA 2012; 37:1480-1487. [PMID: 23227135 DOI: 10.1016/j.phpro.2012.03.748] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We are developing a Time-of-Flight Positron Emission Tomography detector using flat panel micro-channel plate photomultiplier tubes (MCP PMT). The high-speed waveform sampling data acquisition is adopted to exploit the fast time response of MCP PMT efficiently by using transmission-line readout scheme. To demonstrate the feasibility of the proposed detector, prototype detector modules were built using Photonis XP85022 MCP PMT, transmission-line board (TL), and high-speed waveform sampling electronics equipped with DRS4 chips. The MCP/TL module was coupled to single LYSO crystal, and experimental tests have been conducted in a coincidence setup to measure the responses to 511 keV annihilation photon. The details of the prototype module, experimental setup, and the preliminary results are presented and discussed.
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Affiliation(s)
- H Kim
- Department of Radiology, University of Chicago, Chicago, IL 60637
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