Comparison of multi-pole shaping and delay line clipping pre-amplifiers for position sensitive NaI(Tl) detectors

Journal Article · Mon Jun 01 04:00:00 EDT 1998 · IEEE Transactions on Nuclear Science

DOI:https://doi.org/10.1109/23.681992· OSTI ID:649394

Freifelder, R; Karp, J S; Wear, J A; Lockyer, N S; Newcomer, F M; Surti, S; Berg, R van ^[1]

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1. Univ. of Pennsylvania, Philadelphia, PA (United States)

NaI(Tl) position sensitive detectors have been used in medical imaging for many years. For PET applications without collimators, the high counting rates place severe demands on such large area detectors. The NaI(Tl) detectors in the PENN-PET scanners are read-out via photomultiplier tubes and preamplifiers. Those preamplifiers use a delay-line clipping technique to shorten the characteristic 240 ns fall time of the NaI(Tl) signal. As an alternative, the authors have investigated a pole-zero network to shorten the signal followed by a multi-pole shaper to produce a symmetric signal suitable for high counting rates. This has been compared to the current design by measuring the energy and spatial resolution of a single detector as a function of different preamplifier designs. Data were taken over a range of ADC integration times and countrates. The new design shows improved energy resolution with short integration times. Effects on spatial resolution and deadtime are reported for large position sensitive detectors at different countrates.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-88ER60642
• OSTI ID: 649394
• Report Number(s): CONF-971147--
• Journal Information: IEEE Transactions on Nuclear Science, Journal Name: IEEE Transactions on Nuclear Science Journal Issue: 3Pt2 Vol. 45; ISSN 0018-9499; ISSN IETNAE
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
55 BIOLOGY AND MEDICINE
BASIC STUDIES
COMPARATIVE EVALUATIONS
IMAGE PROCESSING
POSITION SENSITIVE DETECTORS
POSITRON COMPUTED TOMOGRAPHY
RADIOISOTOPE SCANNERS
SPATIAL RESOLUTION